PRACTICAL GUIDE. Low-voltage power systems Protection against overvoltages

Transcription

1 PRACTICAL GUIDE Low-voltage power systems Protection against overvoltages

2 Introduction Overvoltage Since the 1960s, the purely technical term EMC (electromagnetic compatibility) has become a term comprising not only safety for appliances and components, but in particular, for their users. Apart from others, it refers to the resistance of devices and equipment to all forms of electromagnetic disturbance, including impulse overvoltage and high frequency disturbance. It is thus the suppliers who must increase the resistance of systems today. A correctly designed and installed system of surge protective devices and SALTEK filters can satisfy even the most demanding requirements for the safety of equipment in terms of electromagnetic compatibility. The current standard of technology offers good protection for electronic and electrical equipment against the effects of dangerous impulse overvoltage, i.e., surge arresters. Equipment can be protected not only against the effects of a destructive impulse that features great energy, but also against the effects of high frequency disturbances. Unprotected electrical wiring, computer and data networks always pose a huge risk for their users. Installing overvoltage protection devices therefore prevents possible damage. The price of surge arresters is oniy a tiny part of the cost expended on protected equipment and a negligible amount compa to the potential damage resulting from a failure or destruction of the technological equipment followed by financial losses. SALTEK surge arresters are complied Czech and inter- national standards. Overvoltage types Basically, overvoltage can be classed according to its duration. Transient overvoltage short-term changes in voltage: overvoltage that lasts a short time not exceeding several thousandths of a second, oscillating or non-oscillating, usually highly damped, in hunds of microseconds (see Fig. 1a) such overvoltage can be successfully eliminated using an SPD. Temporary overvoltage long-term changes in voltage: overvoltage with industrial frequency of oscillation and a relatively long duration in milliseconds or less (see Fig. 1b) such overvoltage cannot be eliminated by means of an SPD. Fig. 1a Overvoltage caused by lightning Transient overvoltage Switching overvoltage 230 V, 50 Hz Fig. 1b Temporary overvoltage Electronic components damaged by overvoltage Overvoltage 230 V, 50 Hz 2

3 Practical Guide - Low-voltage power systems Short-term changes in voltage, i.e. transient overvoltage can be classed in several groups according to the origin: differential mode of overvoltage: overvoltage between live conductors (L1-L2, L-N with LV supply, a-b with telecommunications ), such overvoltage occurs as a result of technological events e.g. switching of non-linear loads (motors, refrigerators,...). These are particularly dangerous for electronic equipment, sensitive hardware-like control systems, computers and their software utilities, etc. (see Fig. 2) common mode of overvoltage: overvoltage between the neutral conductor and earthing conductor (L-PE, N-PE in LV, a/b-pe in telecommunications ) that results from atmospheric events a lightning strike. Such overvoltages are particularly dangerous for technology, the frame of which is earthed (insulation breakdown). (see Fig. 3) An SPD in the supply network will be selected according to the type of respective overvoltage. L N Fig. 2 Fig. 3 L N Differential mode (switching) of overvoltage Common mode (lightning) of overvoltagee Overvoltage wave parameters Fig. 4 Impulse front time Impulse tail time 50 10/350 μs i (ka) t (μs) Test impulse 10/350 µs simulates a lightning strike and SPD type 1 and SPD type 1+2 are tested according to it 3

4 Fig /20 μs Protection of technology against overvoltage i (ka) 25 The principle of surge protective devices is based on the equipotential bonding. This is conditioned by the effective equalising potential in the whole building. It is only possible if the whole building is thoroughly provided with equipotential bonding and it should be connected to the earthing electrode t (μs) If a building features external lightning protection (LPS), both the down conductor as well as the protective conductor of the supply network should be connected to the earthing conductor. This is shown in the following chapter. Test impulse 8/20 µs simulates technological overvoltage and SPD type 2 and SPD type 3 are tested according to it. Fig. 6 Zkušební proudové vlny 10/350 μs a 8/20 μs I sn (ka) 8/20 µs Lightning arresters SPD type 1 10/350 µs Surge arresters SPD type 2 Surge arresters SPD type 2 Comparison of the energy of testing impulses 10/350 µs and 8/20 µs Supply networks SPD connection principles on how to connect SPDs An SPD in power supply networks should be connected in two connection modes mode x+0 and mode x+1. The x+0 connection mode is designated 3+0 (TN-C) or 4+0 (TN-S) for three-phase power supply and 1+0 (TN-C) or 2+0 (TN-S) for single-phase power supply. Such mode is benefi cial in eliminating common mode of overvoltage. The x+1 connection mode is designated 3+1 for three-phase power supply and 1+1 for single-phase power supply. It cannot be used in the TN-C supply network. It is advantageous to use it to eliminate differential mode of overvoltage. 4

5 Practical Guide - Low-voltage power systems TN-S system An SPD type 1 or SPD type 1 and 2 should be located at the incoming supply to the building (mostly in the main distribution board). These SPDs are mainly intended to restrict lightning electromagnetic impulses (lightning strikes) and therefore are installed in the x+0 design, i.e., all live conductors (L1, L2, L3 and N) against ground (PE). An SPD type 2 should be located in a subsidiary distribution board. In such supply networks, an SPD type 2 can either be connected in the x + 0 mode (to eliminate longitudinal lightning electromagnetic impulse) or in the x + 1 mode (to restrict overvoltage in the equipment). An SPD type 3 is always mounted close to the equipment to be protected. TN-C-S system In a TN-C-S supply network, the SPD located before the point from which the PEN conductor separates to the N and PE conductors should always be connected in the x+0 mode. Behind the point of separation, an SPD type 2 can be connected in both x+1 mode or x+0, with the same principle to be followed as in a TN-S network, i.e., such type of connection should be chosen to better suit the respective situation. In a TN-S supply network, connection of a type 2 SPD must follow the type of overvoltage that will prevail in the supply network. Consequently, in industrial operations, where a great number of switching overvoltage occurs, it is more advantageous to connect an SPD type 2 in the x + 1 mode, while in administrative and residential buildings it is better to connect an SPD type 2 in the x + 0 mode. Fig. 7 L1 L2 L3 N PE LPZ 0 SPD type 1 or 1+2 LPZ 1 SPD type 2 LPZ 2 SPD type 2 LPZ 2 Main distribution board Subsidiary distribution board (1) Subsidiary distribution board (2) Origin of the installation F1 RCD SPD type 3 Fine protection 16 A 16 A 63 A *F2 *F3 *F4 External lightning protection Main earthing bonding bar Local earthing bonding bar Local earthing bonding bar * Additional protection of SPD see page 7 Equipment (technology) TN-S system Fig. 8 L1 L2 L3 L1 L2 PEN L3 PEN F1 LPZ 0 SPD type 1 or 1+2 LPZ 1 LPZ 2 SPD type 2 LPZ 2 Main distribution board Subsidiary distribution board (2) Origin of the installation F1 *F2 N PE N PE SPD type 2 Subsidiary distribution board (1) *F3 *F4 RCD RCD 16 A SPD type 3 16 A Fine protection 63 A A 63 A *F2 *F3 *F4 External lightning protection Main earthing bonding bar Local earthing bonding bar Local earthing bonding bar * Additional protection of SPD see page 7 Equipment (technology) TN-C-S system L1 L2 L3 F1 16 A 16 A 63 A 16 Jemná ochrana 5

6 RCD 16 A 63 A L1 F1 TN-C system L2 In a TN-C L3 supply network, an SPD can only be connected in the x+0 mode. In an SPD type 3, manufactu N in the x+1 connection PEN mode, the N conductor (blue) as well PE as the PE conductor (yellow-green) should always be connected to the *F2 PEN conductor. *F3 *F3 *F4 TT system 16 A For a TT supply network, in which only neutral conductors 63 A L1, L2, L3 are routed from the power source, all levels of SPD should always be connected in the x+1 mode. *F4 RCD 16 A obr. 9 L1 L2 L3 LPZ 0 SPD type 1 or 1+2 LPZ 1 LPZ 2 Main distribution board Origin of the installation F1 SPD type 2 Subsidiary distribution board SPD type 3 Fine protection 16 A 16 A 63 A PEN L1 L2 L3 External lightning protection PEN F1 *F2 *F2 Main earthing bonding bar *F3 *F3 Local earthing bonding bar 16 A 16 A 63 A * Additional protection of SPD see page 7 Equipment (technology) TN-C system obr. 10 L1 L2 L3 N překlad LPZ 0 SPD type 1 or 1+2 LPZ 1 SPD type 2 LPZ 2 Origin of the installation Main distribution board Subsidiary distribution board F1 *F2 PE RCD 16 A * 16 předjišťování A SPD viz str A SPD type 3 Fine protection External lightning protection *F2 Main earthing bonding bar *F3 Local earthing bonding bar * Additional protection of SPD see page 7 Equipment (technology) TT system 6

7 Practical Guide - Low-voltage power systems Principle of overcurrent protection of SPD For overcurrent protection of SPD it is important to consider whether we should follow the protection priority principle, which is used in most installations, or the power supply priority principle. a) protection priority principle an SPD should be provided with additional protection in this case only if the value of the line protection (F1 fuse) is higher than the value of the respective SPD shown in the catalogue (F2 fuse) and the SPD protection always has the value shown in the manufacturer s catalogue (parameter maximum additional protection). An example of back-up fuse for SPD FLP-B+C MAXI V in different supply networks. The catalogue value of maximum back-up fuse for FLP-B+C MAXI V is 250 A, and 125 A for the V connection. 1 TN-C Parallel connection V (series) connection F1 125 A FLP-B+C MAXI V červená U c: 260 V~ I imp: 25 ka I n: 30 ka I max: 60 ka U p: < 1,5 kv 250 A FLP-B+C MAXI V červená U c: 260 V~ I imp: 25 ka I n: 30 ka I max: 60 ka U p: < 1,5 kv 250 A FLP-B+C MAXI V červená U c: 260 V~ I imp: 25 ka I n: 30 ka I max: 60 ka U p: < 1,5 kv 250 A F1 > 250 A F2 F1 250 A F2 F1 > 125 A F1 125 A FLP-B+C MAXI V červená U c: 260 V~ I imp: 25 ka I n: 30 ka I max: 60 ka U p: < 1,5 kv 250 A FLP-B+C MAXI V červená U c: 260 V~ I imp: 25 ka I n: 30 ka I max: 60 ka U p: < 1,5 kv 250 A FLP-B+C MAXI V červená U c: 260 V~ I imp: 25 ka I n: 30 ka I max: 60 ka U p: < 1,5 kv 250 A 2 TN-C-S F1 125 A N PE N PE FLP-B+C MAXI V červená U c: 260 V~ I imp: 25 ka I n: 30 ka I max: 60 ka U p: < 1,5 kv 250 A FLP-B+C MAXI V červená U c: 260 V~ I imp: 25 ka I n: 30 ka I max: 60 ka U p: < 1,5 kv 250 A FLP-B+C MAXI V červená U c: 260 V~ I imp: 25 ka I n: 30 ka I max: 60 ka U p: < 1,5 kv 250 A F1 > 250 A F2 F1 250 A F2 F1 > 125 A F1 125 A FLP-B+C MAXI V červená U c: 260 V~ I imp: 25 ka I n: 30 ka I max: 60 ka U p: < 1,5 kv 250 A FLP-B+C MAXI V červená U c: 260 V~ I imp: 25 ka I n: 30 ka I max: 60 ka U p: < 1,5 kv 250 A FLP-B+C MAXI V červená U c: 260 V~ I imp: 25 ka I n: 30 ka I max: 60 ka U p: < 1,5 kv 250 A 3 TN-S F1 125 A FLP-B+C MAXI V červená U c: 260 V~ I imp: 25 ka I n: 30 ka I max: 60 ka U p: < 1,5 kv 250 A FLP-B+C MAXI V červená U c: 260 V~ I imp: 25 ka I n: 30 ka I max: 60 ka U p: < 1,5 kv 250 A FLP-B+C MAXI V červená U c: 260 V~ I imp: 25 ka I n: 30 ka I max: 60 ka U p: < 1,5 kv 250 A FLP-B+C MAXI V červená U c: 260 V~ I imp: 25 ka I n: 30 ka I max: 60 ka U p: < 1,5 kv 250 A F1 > 250 A F2 F1 250 A F2 F1 > 125 A F1 125 A FLP-B+C MAXI V červená U c: 260 V~ I imp: 25 ka I n: 30 ka I max: 60 ka U p: < 1,5 kv 250 A FLP-B+C MAXI V červená U c: 260 V~ I imp: 25 ka I n: 30 ka I max: 60 ka U p: < 1,5 kv 250 A FLP-B+C MAXI V červená U c: 260 V~ I imp: 25 ka I n: 30 ka I max: 60 ka U p: < 1,5 kv 250 A FLP-B+C MAXI V červená U c: 260 V~ I imp: 25 ka I n: 30 ka I max: 60 ka U p: < 1,5 kv 250 A 7

8 b) supply priority principle an SPD should always be provided with a back-up fuse in this case, i.e., there are always both F1 and F2 fuses. The value of the SPD back-up (F2 fuse) must be calculated in this case according to the principle of protection selectivity, whereas the value should never be higher than the value specified in the manufacturer s catalogue. Should the calculation show a higher value than that shown in the catalogue, then the value of the SPD back-up fuse is the same as that in the manufacturer s catalogue. Should the value of the SPD back-up be lower than that shown in the catalogue, the whole installation (i.e., the SPD back-up and the SPD itself) should be provided with at least another protection installation next to the original one, as indicated in the example below. An example of additional SPD protection - FLP-12,5 V- in different supply networks. The catalogue value of the maximum back-up for FLP-12,5 V is F2 = 160 A. F2 the value of the SPD back-up established by the calculation 1 TN-C F1 > 160 A F1 F2 = 160 A F2' F2' L3 L2 L1 L1 L2 L3 F2' 160 A F2 F2' < 160 A F2' L3 L2 L1 L1 L2 L3 L3 L2 L1 L1 L2 L3 PEN PEN PEN PEN PEN PEN 2 TN-C-S F1 > 160 A F1 N N PE PE F2 = 160 A F2' F2' L3 L2 L1 L1 L2 L3 F2' 160 A F2 F2' < 160 A F2' PEN TN-S F1 > 160 A F1 F2 = 160 A F2' F2' L1 L2 L3 N F2' 160 A F2 F2' < 160 A F2' PE PE PE N L3 L2 L1 N L3 L2 L1 L1 L2 L3 N L1 L2 L3 N PE PE PE N L3 L2 L1 PEN L3 L2 L1 L3 L2 L1 L1 L2 L3 L1 L2 L3 PEN PEN PEN PEN 3 8

9 Practical Guide - Low-voltage power systems SPD dimensioning Only the SPD type 1 should be dimensioned. Dimensioning of the SPD type 1 should be based on the calculation of the lightning protection level (LPL) for the lightning protection system (LPS). The table from CLC/TS below shows minimum values of the discharge lightning strike current to the pole considering the lightning protection (LPL) class of the building for the SPD type 1. If the LPL value is not known, the worse scenario is anticipated Low voltage networks Table 1 LPL 1 or unknown Maximum current corresponding to LPL 200 ka ka 3 or ka Number of conductors (n) TT TN-C TN-S IT without neutral conductor Connection mode Connection mode Connection mode IT with neutral conductor C C C C C C L-PE N-PE L-N N-PE L-PEN L-PE N-PE L-N N-PE L-PE L-N N-PE I imp (ka) 5 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 33,3 33,3 66,7 33,3 N/A N/A N/A N/A N/A N/A I imp (ka) 5 N/A N/A N/A N/A 15,0 15,0 60,0 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 25,0 25,0 50,0 25,0 N/A N/A N/A N/A N/A N/A I imp (ka) 5 N/A N/A N/A N/A 10,0 10,0 40,0 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A Note: C SPD connected in the x+0 mode; C SPD connected in the x+1 mode C TN-C C TN-S C 9

10 Selection of SPD at the incoming supply to the building For selection of the SPD type 1 at the incoming supply to the building we use the table for SPD type 1 dimensioning (see table 1). At the same time, it is necessary to consider the specifi c situation. Even if the calculation made according to the previous table shows that the Impulse current of SPD type 1 may be, for example, 12.5 ka in a 10/350 µs wave and the building is fed by external cabling, then the probability of a lightning strike in the outdoor line is high and the SPD type 1 would be under-dimensioned. Variants of SPD applications are shown in the following examples: Situation Solution A house with LPS, earthed antenna, or metallic roof, etc. SPD type 1 SPD type 2 A house with an overhead line SPD type 1 SPD type 2 A house with earthed metallic parts or LPS nearby SPD type 1 SPD type 2 1 A family house in a built-up area or a detached structure with or without LPS and overhead line DA-275 A CZ-275 A TN-C SLP-275 V/3 TN-C-S SLP-275 V/3 TN-S SLP-275 V/3+1 or SLP-275 V/4 DA-275 A CZ-275 A TN-C SLP-275 V/3 TN-C-S SLP-275 V/3 TN-S SLP-275 V/3+1 or SLP-275 V/4 TN-C FLP-12,5 V/3 TN-C-S FLP-12,5 V/3 TN-S FLP-12,5 V/4 TN-C FLP-B+C MAXI V(S)/3 TN-C-S FLP-B+C MAXI V(S)/3 TN-S FLP-B+C MAXI V(S)/4 TN-C FLP-B+C MAXI V(S)/3 TN-C-S FLP-B+C MAXI V(S)/3 TN-S FLP-B+C MAXI V(S)/4 10

11 Practical Guide - Low-voltage power systems 2 A detached family house with or without LPS, with a underground cable connection DA-275 A CZ-275 A TN-C SLP-275 V/3 TN-C-S SLP-275 V/3 TN-S SLP-275 V/3+1 or SLP-275 V/4 DA-275 A CZ-275 A TN-C SLP-275 V/3 TN-C-S SLP-275 V/3 TN-S SLP-275 V/3+1 or SLP-275 V/4 TN-C FLP-B+C MAXI V(S)/3 TN-C-S FLP-B+C MAXI V(S)/3 TN-S FLP-B+C MAXI V(S)/4 TN-C FLP-B+C MAXI V(S)/3 TN-C-S FLP-B+C MAXI V(S)/3 TN-S FLP-B+C MAXI V(S)/4 TN-C FLP-12,5 V/3 TN-C-S FLP-12,5 V/3 TN-S FLP-12,5 V/4 3 A family house in a built-up area without LPS and with a underground cable connection DA-275 A CZ-275 A TN-C SLP-275 V/3 TN-C-S SLP-275 V/3 TN-S SLP-275 V/3+1 or SLP-275 V/4 DA-275 A CZ-275 A TN-C SLP-275 V/3 TN-C-S SLP-275 V/3 TN-S SLP-275 V/3+1 or SLP-275 V/4 TN-C FLP-12,5 V/3 TN-C-S FLP-12,5 V/3 TN-S FLP-12,5 V/4 TN-C FLP-12,5 V/3 TN-C-S FLP-12,5 V/3 TN-S FLP-12,5 V/4 11

12 4 Terrace houses with a common LPS and overhead line DA-275 A CZ-275 A TN-C SLP-275 V/3 TN-C-S SLP-275 V/3 TN-S SLP-275 V/3+1 or SLP-275 V/4 TN-C FLP-B+C MAXI V(S)/3 TN-C-S FLP-B+C MAXI V(S)/3 TN-S FLP-B+C MAXI V(S)/4 5 Terrace houses with a common LPS and a underground cable connection DA-275 A CZ-275 A TN-C SLP-275 V/3 TN-C-S SLP-275 V/3 TN-S SLP-275 V/3+1 or SLP-275 V/4 TN-C FLP-12,5 V/3 TN-C-S FLP-12,5 V/3 TN-S FLP-12,5 V/4 12

13 Practical Guide - Low-voltage power systems 6 Blocks of flats with a underground cable connection without the possibility to install an SPD type 1 upstream of power meter TN-C FLP-12,5 V/1 TN-C-S FLP-12,5 V/1 TN-S FLP-12,5 V/2 TN-C FLP-12,5 V/3 TN-C-S FLP-12,5 V/3 TN-S FLP-12,5 V/4 CZ-275 A DA-275 A TN-C FLP-B+C MAXI V(S)/3 TN-C-S FLP-B+C MAXI V(S)/3 TN-S FLP-B+C MAXI V(S)/4 7 Blocks of flats with a underground cable connection with the possibility to install an SPD type 1 upstream of power meter TN-C SLP-275 V/1 TN-C-S SLP-275 V/1 TN-S SLP-275 V/1+1 or SLP-275 V/2 TN-C SLP-275 V/3 TN-C-S SLP-275 V/3 TN-S SLP-275 V/3+1 or SLP-275 V/4 CZ-275 A DA-275 A TN-C FLP-B+C MAXI V(S)/3 TN-C-S FLP-B+C MAXI V(S)/3 TN-S FLP-B+C MAXI V(S)/4 13

14 8 Administrative building DA-275 A or CZ-275 A TN-C SLP-275 V/3 TN-C-S SLP-275 V/3 TN-S SLP-275 V/3+1 or SLP-275 V/4 TN-C SLP-275 V/3 TN-C-S SLP-275 V/3 TN-S SLP-275 V/3+1 or SLP-275 V/4 TN-C FLP-B+C MAXI V(S)/3 TN-C-S FLP-B+C MAXI V(S)/3 TN-S FLP-B+C MAXI V(S)/4 14

15 Practical Guide - Low-voltage power systems 9 A commercial building or or a TN-C FLP-B+C MAXI V(S)/3 TN-C-S FLP-B+C MAXI V(S)/3 TN-S FLP-B+C MAXI V(S)/4 TN-C FLP-25--V(S)/3 TN-C-S FLP-25--V(S)/3 TN-S FLP-25--V(S)/4 TN-C 3 pce. FLP-SG50 V(S)/1 TN-C-S 3 pce. FLP-SG50 V(S)/1 TN-S 4 pce. FLP-SG50 V(S)/1 TN-C SLP-275 V/3 TN-C-S SLP-275 V/3 TN-S SLP-275 V/4 10 A commercial building of special importance TN-C 3 pce. FLP-SG50 V(S)/1 TN-C-S 3 pce. FLP-SG50 V(S)/1 TN-S 4 pce. FLP-SG50 V(S)/1 15

16 11 Administrative and commercial premises DA-275 A or TN-C SLP-275 V/3 TN-C-S SLP-275 V/3 TN-S SLP-275 V/4 TN-S DA-275 DF16 CZ-275 A TN-C SLP-275 V/3 TN-C-S SLP-275 V/3 TN-S SLP-275 V/4 TN-S DA-275 DF25 TN-S SLP-275 V/3+1 TN-C FLP-B+C MAXI V(S)/3 TN-C-S FLP-B+C MAXI V(S)/3 TN-S FLP-B+C MAXI V(S)/4 TN-S DA-275 V/3+1 16

17 Practical Guide - Low-voltage power systems TN-S SLP-275 V/3+1 TN-S DA-275 DF25 TN-S SLP-275 V/3+1 TN-S DA-275 DF16 TN-C 3 pce. FLP-SG50 V(S)/1 TN-C-S 3 pce. FLP-SG50 V(S)/1 TN-S 4 pce. FLP-SG50 V(S)/1 TN-S DA-275 V/3+1 TN-S FLP-12,5 V/3+1 17

18 12 A building with LPS and air conditioner or heating cables in gutters TN-C FLP-12,5 V/1 TN-C-S FLP-12,5 V/1 TN-S FLP-12,5 V/2 TN-C FLP-B+C MAXI V(S)/3 TN-C-S FLP-B+C MAXI V(S)/3 TN-S FLP-B+C MAXI V(S)/4 DA-275 A or CZ-275 A 13 A house with a single-phase power supply and LPS (LPL I) 1 Double- 2 -conductor supply Three- -conductor supply TN-C 1 pce. FLP-SG50 V(S)/1 TN-C-S 1 pce. FLP-SG50 V(S)/1 TN-S 2 pce. FLP-A35 18

19 Practical Guide - Low-voltage power systems Reducing overvoltage in LPZ zones The principle of ucing voltage using zones lies in progressive uction of the overvoltage level to a safe value that will not damage the specifi c equipment or technology. To obtain a safe overvoltage value, the whole structure is divided into individual zones and the SPD is installed at the boundary between the zones. LPZ 0 A LPZ 1 LPZ 0 A LPZ 2 LPZ 3 LPZ 3 LPZ 2 LPZ 3 LPZ 3 LPZ 3 LPZ 0 B LPZ 2 LPZ 0 B LPZ 3 LPZ 3 LPZ 1 L1 L2 L3 PEN LPZ 0 SPD type 1 or 1+2 LPZ 1 SPD type 2 LPZ 2 SPD type 2 LPZ 2 Main distribution board Subsidiary distribution board (1) Subsidiary distribution board (2) Origin of the installation F1 N PE RCD SPD type 3 Fine protection 16 A 16 A 63 A *F2 *F3 *F4 External lightning protection Main earthing bonding bar Local earthing bonding bar Local earthing bonding bar * Additional protection of SPD see page 7 Equipment (technology) 19

20 SPD mounting principles Principle 1 length of connecting conductors If you want to protect equipment, there are several things to remember when installing an SPD, i.e., apart from its diverting ability, it is the maximum value of voltage protective level to be withheld by the equipment at its terminals considering the installation method. Protection level U p and the drop in voltage at the supply conductors U must not exceed the withstand voltage at the terminals of the equipment. Fig. 11 clearly shows that the aggregate protection level is given by adding partial uctions in voltage, while such a sum must not exceed the withstand voltage U w at the terminals of the equipment. U w > U p + U 1 + U 2 where U w withstand voltage U p voltage protection level U 1, U 2 uction in voltage at the supply conductor. The impedance of supply conductors for high frequency currents is approximately 1 µh per 1 m of conductor length. The voltage drop in this conductor is given by the formula: U = L di/dt So with a steepness of the pulse rise time of 1 ka/µs, there is a uction of 1,000 V per 1 m of length, which is added to the protection voltage level of the SPD itself. With the total length of supply conductors being 0.5 m, 500 V will be added to the protection voltage level Up. Consequently, the length of the supply conductors must be as short as possible and should not exceed an aggregate length of 0.5 m, as shown in the following fi gures (Fig. 12 and Fig. 13), depicting the connection options. Fig. 11 U 1 OCP a U W SPD U p U 2 b Fig. 12 Fig. 13 a b c a + b 0,5 m c 0,5 m 20

21 Practical Guide - Low-voltage power systems The two practical examples below show that it is possible to meet the stipulated conductor length 0.5 m in practice for connecting the SPD. Before the intervention: The SPD installation fails to meet the condition the length of supply conductors for the SPD After the intervention: By relocating the SPD, the condition will be satisfied the length of supply conductors for the SPD Before the intervention: The SPD installation fails to meet the condition the length of supply conductors After the intervention: By relocating the SPD, the condition will be satisfied 21

22 Principle 2 SPD location in the distribution board An SPD in the distribution board is located at the entry of the customer s structure, to eliminate surges coming in the supply line as soon as possible and to prevent the effects on appliances in the distribution board. This will make sure that the unprotected conductors (affected by overvoltage) are as short as possible. The overvoltage that could induce the protected conductors (conductors protected by the SPD), is minimized in this way. Basic options are shown in Fig.14. Fig. 14 a) b) c) d) EBB The next fi gure shows option c) directly in practice from Fig. 14. Before the intervention: The SPD installation fails to meet the condition the length of supply conductors for the SPD After the intervention: By adding a terminal block and connecting a PEN conductor, these conditions will be satisfi ed 22

23 Practical Guide - Low-voltage power systems +1 Before the intervention: The SPD installation fails to meet the condition the length of supply conductors for the SPD and also the SPD connection for the TN-S system After the intervention: By relocating the circuit breaker and the SPD, the conditions will be satisfi ed; and by adding one more SPD, the N conductor will also be protected. Principle 3 loops The surface of a loop consisting of conductors (L, N and PE) must be as small as possible to minimize the overvoltage induced in the loop and to considerably uce the effects of such overvoltage on other equipments (technology) connected in the distribution board. The principle of minimizing the loop is shown in Fig. 14 and the following examples. Before the intervention After the intervention: By turning the SPD, the connection in the distribution board will be better arranged and, at the same time, the condition from IEC /2008 (CLC/TS /2009) concerning loops will be satisfi ed 23

24 Before the intervention After the intervention: By relocating the SPD, the connection in the distribution board will be better arranged, the condition concerning loops specifi ed in IEC /2008 (CLC/TS /2009) will be satisfi ed and, at the same time, the condition stipulating the length of supply conductors for the SPD will be met as well Principle 4 conductor routing in the distribution board When routing the conductors in the distribution board it is always necessary to separate protected ( clean ) and unprotected ( dirty ) conductors. To minimise the bonding between the different types of conductors ( clean and dirty ), it is essential to keep the distance between them as great as possible (over 30 cm). If such a distance is impossible to observe, a protection partition should be placed between them, see Fig. 15. If you cannot avoid crossing of protected and unprotected conductors, the crossing should be made in the right angle to prevent induction of interference pulses in the protected conductors, as shown in Fig. 16. Fig. 15 > 30 cm Unprotected cable Protected cable < 30 cm < 30 cm Unprotected cable Protected cable Unprotected cable Divider Protected cable Fig. 16 Unprotected cable Unprotected cable 90 Protected cable Protected cable 24

25 Practical Guide - Low-voltage power systems Coordination of SALTEK principles To achieve correct operation of individual SPD levels, specifi c distances should be observed between them. A general solution is shown in Fig. 17 and Fig. 19. Fig. 18 shows incorrect coordination between individual SPDs. Should it be impossible to observe the coordination distances between the specifi c protection levels, the distance can be extended using coordination RTO impendences. These coordination impendences must be dimensioned to the current fl owing through the line. This can be established from the value of the circuit protection. Since it is rather diffi cult to apply RTO if the distances between the individual protection levels in higher continuous currents are not observed, we use a coordinated SPD type 1 with the relevant SPD type 2. Fig. 17 L 10 m L 5 m Type 1 Type 2 Type 3 Fig. 18 L < 10 m L < 5 m Type 1 Type 2 Type 3 Fig. 19 L < 10 m L < 5 m RTO RTO Type 1 Type 2 Type 3 25

26 If the lightning arrester FLP-SG50 V/1 is used as an SPD type 1 and SLP-275 V is used as an SPD type 2, it will not be necessary to keep the distance between them over 10 m, because they are mutually coordinated and can be mounted next to each other (see Fig. 20). If, for example, FLP-B++C MAXI V is installed as an SPD type 1, which is an SPD type 1+2 with Up < 1.5 kv and the distance between this SPD and the next one exceeds 10 m, an SPD type 2 should be located behind the SPD type 1+2, e.g., SLP-275 V (see Fig. 21). If the distance between this SPD and the next one is less than 10 m, you will not need to install an SPD type 2 behind the SPD type 1+2. The same applies oniy if an SPD type 2 is used instead of an SPD type 1+2 (see Fig. 22). Fig m < L < 10 m L 5 m Type 1 Type 2 Type 3 FLP-SG50 V /1 SLP-275 V* * according to type of connection Fig. 21 L 10 m L 5 m Type Type 2 Type 3 FLP-B+C MAXI V* SLP-275 V* * according to type of connection L 5 m Fig. 22 L 10 m L 5 m Type 2 Type 2 Type 3 SLP-275 V* SLP-275 V* * according to type of connection L 5 m 26

27 Practical Guide - Low-voltage power systems Since there are situations in practice where the technology is connected directly from the main distribution board and the technology distribution board is usually at a distance of tens of meters, it is advisable to install an SPD in the technology distribution board to cope with overvoltage as well as different earth potentials that might occur there, particularly if the earthing (equipotential bonding) is not completely all right. Consequently, an SPD type 1+2, featuring a diverting ability of In = 30 ka (8/20µs), should be installed in the position of the SPD type 2, whose diverting ability is In = 20 ka (8/20µs), to work In this case as a strong SPD type 2 (see Fig and Fig ). Protective distance To protect specifi c equipment, an SPD should be installed as close as possible to the protected equipment. If the SPD-SPD or SPD-technology distances are too great, the line features refl ections which can destroy the technology or the line insulation. These refl ections can even double the Up protection voltage level. The doubling effect occurs if the equipment is disconnected inside or its input impedance is high. If the distance between the SPD and the technology is L 10 m, refl ections need not be taken into consideration. If the distance is great (L>> 10 m), remember to install an additional SPD (see Fig and Fig ). Fig. 23 L > 50 m Fig. 24 L > 50 m Type 1 Type 2 Type 1 Type 1+2 FLP-SG50 V /1 FLP-SG50 V /1 SLP-275 V/1+1 FLP-12,5 V/1+1 Fig. 25 L > 100 m Fig. 26 L > 100 m Type 1 Type 2 Type 1 Type 1+2 FLP-SG50 V /1 FLP-SG50 V /1 SLP-275 V/1+1 FLP-B+C MAXI V/2 Fig. 27 L >> 10 m Fig. 28 L > 10 m Type 1+2 Type 2 Type 1+2 FLP-B+C MAXI V/2 FLP-B+C MAXI V/2 SLP-275 V/1+1 Fig. 29 L > 10 m Fig. 30 L > 5 m Type 2 Type 2 Type 3 SLP-275 V/1+1 SLP-275 V/1+1 DA-275 V/1+1 27

28 The protective distance of the SPD is always uced as a result of the voltage induced by lightning current or switching of the technology connected to same circuit. This is why the distance between an SPD and the technology must not exceed 5 m. This is of particular importance in protecting highly sensitive equipment, such as electronic security systems, electronic fi re signalling systems, PLC and other processor-controlled technology that is also prone to induced switching overvoltage. Such overvoltage with a very short duration (in µs) and a small pulse amplitude (hunds of volts) would pass up to the equipment, which will not be destroyed, but it can affect processor freezing or damage or erase memory chips or impair the functionality of the equipment. Hence, an SPD type 3 with a VF fi lter, able to cope with this problem, should be installed in these cases. An example of the connection of an SPD type 3 with a VF fi lter is shown in Fig. 31 and Fig. 32. Socket circuits with SPD type 3 Consideration should be taken regarding socket circuits, which are usually very long and are used in different situations. The protective distance of an SPD type 3 in socket circuits is less than 5 m down the cable, as shown in Fig. 33. To ensure correct functioning of an SPD type 3, both protection levels SPD type 1 and SPD type 2 should be mounted before. Socket circuitry featuring all sockets either with integrated SPD type 3 protection or available with SPD type 3 protection for additional installation (see Fig. 34), is always used in heavily disturbed environments, or places with a number of electrical appliances. Laboratories are a typical example of such environment. Fig. 31 L > 5 m L < 5 m Type 1+2 FLP-B+C MAXI V/2 Type 3 DA-275 DF 16 Fig. 32 L > 5 m L < 5 m Type 2 SLP-275 V/1+1 Type 3 DA-275 DF 16 Fig. 33 < 5 m < 5 m Fig. 33a Application of SPD type 3 for additional mounting in different types of sockets CZ-275 A A socket with integrated SPD type 3 Earth Pin SCHUKO DA-275 A 28

29 Practical Guide - Low-voltage power systems Fig. 34 A socket with integrated SPD type 3 SPD type 3 for additional installation (DA or CZ according to type of sockets see Fig. 33a) DA-275 A DA-275 A DA-275 A DA-275 A DA-275 A CZ-275 A CZ-275 A CZ-275 A CZ-275 A CZ-275 A To uce the number of SPD type 3 in socket circuitry, protective distances of SPD type 3 protection, being below 5 m, are used as standard. In these cases, it is not necessary to equip all sockets with SPD type 3 protection. The basic principle to follow in this method of installing an SPD type 3 is that the SPD must always be installed at the fi rst socket in the socket circuit; the protective distance principle for SPD type 3, as shown in Fig. 35, can be applied only after that. Fig. 36 shows an example of incorrect application of the protective distance. The principle of protective distance cannot be applied to situations where one side of the wall features a socket circuit with, for example, a down conductor bar or an unprotected ascending LV line situated on the other side of the wall. All sockets in this place should be provided with an SPD type 3, as shown in Fig. 37 and Fig. 38. Fig. 35 < 5 m < 5 m < 5 m < 5 m DA-275 A DA-275 A DA-275 A Fig. 36 < 5 m < 5 m < 5 m < 5 m DA-275 A DA-275 A 29

30 If this principle is not observed, the problem located at the LV line bar will induce in the socket circuit and will damage the technology connected to the specifi c socket. Administrative buildings feature a great number of socket circuits with many sockets. To uce the number of SPDs in such cases, not only the protective distance for the SPD type 3 is used, but also so-called installations in groups, as shown in the following examples. If distances between individual groups exceed 5 m, as shown in Fig. 39, the passage socket group must be provided with an SPD type 3 at the fi rst and last socket. Fig. 37 < 5 m < 5 m < 5 m < 5 m DA-275 A DA-275 A DA-275 A DA-275 A for example, the down conductor bar Fig. 38 < 5 m < 5 m < 5 m < 5 m DA-275 A DA-275 A DA-275 A for example, the down conductor bar Fig. 39 > 5 m DA-275 A passage group DA-275 A last group 30

31 Practical Guide - Low-voltage power systems If the group is not a passage group, an SPD type 3 should always be installed at the fi rst socket. Should the distance between individual socket groups be less than 5 m, you can use the property of the SPD protective distance, i.e., you do not need to install an SPD type 3 at the last socket in the passage group, as shown in Fig. 40. The principle of protective distance cannot be applied in situations where the distance between two groups is less than 5 m, and, for example, a down conductor bar or an unprotected LV line is located on the other side of the wall. It is necessary in this case that the last socket of the passage group be provided with an SPD type 3. This option is shown in Fig. 41. SPD connection considering U p (protective voltage level) Connection of SPDs in sequence is shown in the following fi gures (Fig and Fig ). Fig. 40 < 5 m DA-275 A passage group DA-275 A last group Fig. 41 passage group < 5 m last group DA-275 A for example, the down conductor bar DA-275 A Fig. 42 Fig. 43 Type 1+2 U p (L-N) 1.5 kv Type 3 U p (L-N) 1.0 kv Type 2 U p (L-N) 1.2 kv Type 3 U p (L-N) 1.0 kv Fig Fig. 45 Type 1 U p (L-N) 2.5 kv Type 3 U p (L-N) 1.0 kv Type 1 U p (L-N) 2.5 kv Type 2 U p (L-N) 1.2 kv 31

32 SALTEK SPD applications in LV distribution systems Type of structure system main distribution board (in the structure) sub-distribution board (in the same structure) end consumer Family houses, administrative buildings, technologic units, industrial structures Blocks of flats with 12 or more apartments (SPD located in the apart. distr. boards) Demanding applications (structures operations classified at the risk of explosion, chemical plants, structures of a very high importance) 3-ph. TN-C FLP-B+C MAXI VS/3, FLP-B+C MAXI V/3 FLP-25--VS/3, FLP-25--V/3 FLP-25--VS/3, FLP-25--V/3 FLP-B+C MAXI VS/3, FLP-B+C MAXI V/3 FLP-25--VS/3 + SLP-275 V/3 S FLP-25--V/3 + SLP-275 V/3 (also with terminals to the equipment) 3-ph. TN-S FLP-B+C MAXI VS/4, FLP-B+C MAXI V/4 FLP-25--VS/4, FLP-25--V/4 3-ph. TN-C-S 3-ph. TN-C 3-ph. TN-S 3-ph. TN-C-S 1-ph. TN-C 1-ph. TN-S 3-ph. TN-C 3-ph. TN-S 3-ph. TN-C-S FLP-25--VS/4, FLP-25--V/4 FLP-B+C MAXI VS/4, FLP-B+C MAXI V/4 FLP-25--VS/4 + SLP-275 V/4 S FLP-25--V/4 + SLP-275 V/4 (also with terminals to the equipment) FLP-B+C MAXI VS/3, FLP-B+C MAXI V/3 FLP-25--VS/3, FLP-25--V/3 FLP-25--VS/3, FLP-25--V/3 FLP-B+C MAXI VS/3, FLP-B+C MAXI V/3 FLP-25--VS/3 + SLP-275 V/3 S FLP-25--V/3 + SLP-275 V/3 (also with terminals to the equipment) division in the apartment distr. board 3 FLP-SG50 V(S) with terminals to the equipment 3 FLP-SG50 V(S) + 1 SLP-275 V/3(S) 4 FLP-SG50 V(S) with terminals to the equipment 4 FLP-SG50 V(S) + 1 SLP-275 V/4(S) division in the main distribution board 3 FLP-SG50 V(S) with terminals to the equipment 3 FLP-SG50 V(S) + 1 SLP-275 V/4(S) distance > 10 m SLP-275 V/3(S) distance > 50 m FLP-12.5 V/3(S) distance > 100 m FLP-B+C MAXI V/3, FLP-B+C MAXI VS/3 distance < 10 m SLP-275 V/3(S) distance > 10 m SLP-275 V/3(S) distance > 50 m FLP-12.5 V/3(S) distance > 100 m FLP-B+C MAXI V/3, FLP-B+C MAXI VS/3 distance > 10 m SLP-275 V/4(S) distance > 50 m FLP-12.5 V/4(S) distance > 100 m FLP-B+C MAXI V/4, FLP-B+C MAXI VS/4 distance < 10 m SLP-275 V/4(S) distance > 10 m SLP-275 V/4(S) distance > 50 m FLP-12.5 V/4(S) distance > 100 m FLP-B+C MAXI V/4, FLP-B+C MAXI VS/4 distance > 10 m SLP-275 V/4(S) distance > 50 m FLP-12.5 V/4(S) distance > 100 m FLP-B+C MAXI V/4, FLP-B+C MAXI VS/4 distance < 10 m SLP-275 V/4(S) distance > 10 m SLP-275 V/4(S) distance > 50 m FLP-12.5 V/4(S) distance > 100 m FLP-B+C MAXI V/4, FLP-B+C MAXI VS/4 FLP-12.5 V/3(S) FLP-12.5 V/4(S) FLP-12.5 V/3(S) FLP-B+C MAXI V/1, FLP-B+C MAXI VS/1 FLP-12.5 V/2(S) distance < 10 m 1 SLP-275 V/3(S) distance > 10 m SLP-275 V/3(S) distance > 50 m FLP-12.5 V/3(S) distance > 100 m FLP-B+C MAXI V/3, FLP-B+C MAXI VS/3 distance < 10 m 1 SLP-275 V/4(S) distance > 10 m SLP-275 V/4(S) distance > 50 m FLP-12.5 V/4(S) distance > 100 m FLP-B+C MAXI V/4, FLP-B+C MAXI VS/4 distance < 10 m 1 SLP-275 V/4(S) distance > 10 m SLP-275 V/4(S) distance > 50 m FLP-12.5 V/4(S) distance > 100 m FLP-B+C MAXI V/4, FLP-B+C MAXI VS/4 distance > 5 m overvoltage protection to DIN rail: DA-275 V/1(S)+1 (to 63 A) DA-275 V/3(S)+1 (to 63 A) DA-275 DJ (to 16 A) overvoltage protection to a DIN rail with a vf filter: DA-275 DFx (S) (x = 2, 6, 10, 16 A) DA-275 DF 25 for 25 A DA-275 DFIx (x = 1, 6, 10, 16 A) RACK-PROTECTOR multiple sockets to 19"stands CZ-275 A, DA-275 CZS DA-275 A, DA-275 S for additional assembly to the sockets and appliances sockets with overvoltage protection (ABB) XX-overdrive socket adapters distance < 5 m place before the overvoltage protection RTO-xx (xx rated current 16, 35 or 63 A) number acording to connection 1-phase TN-C 1x RTO-xx 1-phase TN-S 2x RTO-xx 3-phase TN-C 3x RTO-xx 3-phase TN-S 4x RTO-xx 32

33 Practical Guide - Low-voltage power systems SALTEK SPD applications in LV distribution systems Type of structure system main distribution board (in the structure) sub-distribution board (in the same structure) end consumer Structures equipped with ESE (active down conductor) Technology with 1-phase connection 3-ph. TN-C 3x FLP-A35 distance > 10 m SLP-275 V/3(S) distance > 50 m FLP-12.5 V/3(S) distance > 100 m FLP-B+C MAXI V/3, FLP-B+C MAXI VS/3 3x FLP-SG50 V(S) distance < 10 m SLP-275 V/3(S) also with terminals to the equipment 3x FLP-SG50 V(S) + SLP-275 V/3(S) distance > 10 m SLP-275 V/3(S) distance > 50 m FLP-12.5 V/3(S) distance > 100 m FLP-B+C MAXI V/3, FLP-B+C MAXI VS/3 3-ph. TN-S 4x FLP-A35 distance > 10 m SLP-275 V/4(S) distance > 50 m FLP-12.5 V/4(S) distance > 100 m FLP-B+C MAXI V/4, FLP-B+C MAXI VS/4 4x FLP-SG50 V(S) distance < 10 m SLP-275 V/4(S) also with terminals to the equipment 4x FLP-SG50 V(S) + SLP-275 V/4(S) distance > 10 m SLP-275 V/4(S) distance > 50 m FLP-12.5 V/4(S) distance > 100 m FLP-B+C MAXI V/4, FLP-B+C MAXI VS/4 3-ph. TN-C-S 3x FLP-A35 distance > 10 m SLP-275 V/4(S) distance > 50 m FLP-12.5 V/4(S) distance > 100 m FLP-B+C MAXI V/4, FLP-B+C MAXI VS/4 3x FLP-SG50 V(S) distance < 10 m SLP-275 V/4(S) 1-ph. TN-C 1-ph. TN-S 1-ph. TN-C-S also with terminals to the equipment 3x FLP-SG50 V(S) + SLP-275 V/3(S) FLP-SG50 V(S)/1 with terminals to the equipment FLP-SG50 V(S)/1 + SLP-275 V/1(S) 2 FLP-SG50 V(S)/1 with terminals to the equipment 2 FLP-SG50 V(S)/1 + 1 SLP-275 V/2(S) Division in the main distribution board FLP-SG50 V(S)/1 with terminals to the equipment FLP-SG50 V(S)/1 + SLP-275 V/1(S) distance > 10 m SLP-275 V/4(S) distance > 50 m FLP-12.5 V/4(S) distance > 100 m FLP-B+C MAXI V/4, FLP-B+C MAXI VS/4 distance < 10 m SLP-275 V/1(S) distance > 10 m SLP-275 V/1(S) distance > 50 m FLP-12.5 V/1(S) distance > 100 m FLP-B+C MAXI V/1, FLP-B+C MAXI VS/1 distance < 10 m 1 SLP-275 V/2(S) distance > 10 m 1 SLP-275 V/2(S) distance > 50 m 1 FLP-12.5 V/2(S) distance > 100 m FLP-B+C MAXI V/2, FLP-B+C MAXI VS/2 distance < 10 m 1 SLP-275 V/2(S) distance > 10 m 1 SLP-275 V/2(S) distance > 50 m 1 FLP-12.5 V/2(S) distance > 100 m FLP-B+C MAXI V/2, FLP-B+C MAXI VS/2 distance > 5 m overvoltage protection to DIN rail: DA-275 V/1(S)+1 (up to 63 A) DA-275 V/3(S)+1 (up to 63 A) DA-275 DJ (up to 16 A) Overvoltage protection to DIN rail with vf filter: DA-275 DFx (S) (x = 2, 6, 10, 16 A) DA-275 DF 25 for 25 A DA-275 DFIx (x = 1, 6, 10, 16 A) RACK-PROTECTOR multiple sockets for 19"stands CZ-275 A, DA-275 CZS DA-275 A, DA-275 S For additional mounting to sockets and appliances Sockets with overvoltage protection (ABB) XX-overdrive Socket adapters distance < 5 m SPD back-up RTO-xx (xx rated current 16, 35 or 63 A) number acording to connection 1-phase TN-C 1x RTO-xx 1-phase TN-S 2x RTO-xx 3-phase TN-C 3x RTO-xx 3-phase TN-S 4x RTO-xx 33

34 Lightning current arresters Spark gaps FLP-SG50 V/1 I imp = 50 ka (10/350 µs) I n = 50 ka (8/20 µs) SPD type 1 lightning current arrester A high-performance spark gap specifi ed for installations in LV cabling, at the boundary of the LPZ 0 and LPZ 1 zones, and for protection against overvoltage effects in direct as well as indirect lightning strikes in the most exacting applications both in heavy industry and chemicals industry, power plants, etc. FLP-SG50 V/1 is coordinated with the type 2 SPD SLP-275 V (S) also without surge separating inductors. FLP-SG50 VS/1 I imp = 50 ka (10/350 µs) I n = 50 ka (8/20 µs) SPD type 1 lightning current arrester A high-performance spark gap specifi ed for installations in LV cabling, at the boundary of the LPZ 0 a LPZ 1 zones, and for protection against overvoltage effects in direct as well as indirect lightning strikes in the most exacting applications both in heavy industry and chemicals industry, power plants, etc. FLP-SG50 VS/1 is coordinated with the type 2 SPD SLP-275 V(S) also without surge separating inductors. FLP-A35 I imp = 35 ka (10/350 µs) I n = 35 ka (8/20 µs) U p 4.0 kv SPD type 1 lightning current arrester A high-performance encapsulated spark gap specifi ed for installations in LV cabling, at the boundary of the LPZ 0 a LPZ 1 zones, and protection against overvoltage effects in direct as well as indirect lightning strikes. Coordination of FLP-A35 with SPD type 2 (SLP-275 V) is provided by installing a surge separating inductor or by correct distance. Spark gaps between N and PE FLP-A50N VS/NPE U c = 255 V AC I imp = 50 ka (10/350 µs) I n = 50 ka (8/20 µs) I max = 100 ka (8/20 µs) FLP-A100N VS/NPE U c = 255 V AC I imp = 100 ka (10/350 µs) I n = 100 ka (8/20 µs) I max = 100 ka (8/20 µs) SPD type 1 lightning current arrester A spark gap for N-PE with a replaceable module, specifi ed for installation in LV cabling, at the boundary of the LPZ 0 and LPZ 1 zones, and for protection against overvoltage effects in direct as well as indirect lightning strikes, for connecting SPD type 1 in the 1+1 mode. ATTENTION! Only specifi ed for connections between N and PE! SPD type 1 lightning current arrester A spark gap pro N-PE with a replaceable module, specifi ed for installation in LV cabling, at the boundary of the LPZ 0 a LPZ 1 zones, and for protection against overvoltage effects in direct as well as indirect lightning strikes for connecting SPD type 1 in the 3+1 mode. ATTENTION! Only specifi ed for connections between N and PE! 34

35 Practical Guide - Low-voltage power systems Lightning current arresters Combined lightning current arresters SPD type 1 FLP-25--V/3 I imp = 25 ka (10/350 µs) Zero leakage current No follow-on current FLP-25--VS/3 I imp = 25 ka (10/350 µs) Zero leakage current No follow-on current Status remote signalling FLP-25--V/4 I imp = 25 ka (10/350 µs) Zero leakage current No follow-on current FLP-25--VS/4 I imp = 25 ka (10/350 µs) Zero leakage current No follow-on current Status remote signalling FLP-25--V/3+1 I imp = 25 ka (10/350 µs) U p 2.2 kv (L-PE) Zero leakage current No follow-on current FLP-25--VS/3+1 I imp = 25 ka (10/350 µs) U p 2.2 kv (L-PE) Zero leakage current No follow-on current Status remote signalling SPD type 1 lightning current arrester A three-pole high-performance lightning current arrester for installation in LV cabling at the boundary of the LPZ 0A LPZ 1 zones and higher levels. It is used to protect against overvoltage effects in direct as well as indirect lightning strikes. It can be used in a variety of installations, suitable for family houses, administrative and commercial buildings, or in sub-distribution boards of large premises. It is specifi ed for three-phase TN-C networks. SPD type 1 lightning current arrester A three-pole high-performance lightning current arrester for installations in LV cabling at the boundary of the LPZ 0A LPZ 1 zones and higher levels. It is used to protect against overvoltage effects in direct as well as indirect lightning strikes. It can be used in a variety of installations, suitable for family houses, administrative and commercial buildings, or in sub-distribution boards of large premises. It is specifi ed for three-phase TN-C networks. SPD type 1 lightning current arrester A four-pole high-performance lightning current arrester for installations in LV cabling at the boundary of the LPZ 0A LPZ 1 zones and higher levels. It is used to protect against overvoltage effects in direct as well as indirect lightning strikes. It can be used in a variety of installations, suitable for family houses, administrative and commercial buildings, or in sub-distribution boards of large premises. It is specifi ed for three-phase TN-S networks. SPD type 1 lightning current arrester A four-pole high-performance lightning current arrester for installations in LV cabling at the boundary of the LPZ 0A LPZ 1 zones and higher levels. It is used to protect against overvoltage effects in direct as well as indirect lightning strikes. It can be used in a variety of installations, suitable for family houses, administrative and commercial buildings, or in sub-distribution boards of large premises. It is specifi ed for three-phase TN-S networks. SPD type 1 lightning current arrester A combination of a three-pole high-performance lightning arrester and encapsulated effi ciency spark gap, connected in the 3+1 mode for installations in LV cabling at the boundary of the LPZ 0 LPZ 1 zones and higher levels. It is used to protect against overvoltage effects in direct as well as indirect lightning strikes. It can be used in a variety of installations, suitable for family houses, administrative and commercial buildings, or in sub-distribution boards of large premises. It is specifi ed for three-phase TT networks. SPD type 1 lightning current arrester A combination of a three-pole high-performance lightning arrester and encapsulated effi ciency spark gap, connected in the 3+1 mode for installations in LV cabling at the boundary of the LPZ 0 LPZ 1 zones and higher levels. It is used to protect against overvoltage effects in direct as well as indirect lightning strikes. It can be used in a variety of installations, suitable for family houses, administrative and commercial buildings, or in subsidiary distribution boards of large premises. It is specifi ed for three-phase TT networks. 35

36 Lightning current arresters Combined lightning current arresters SPD type 1+2 FLP-B+C MAXI V/1 I imp = 25 ka (10/350 µs) I n = 30 ka (8/20 µs) I max = 60 ka (8/20 µs) Zero leakage current No follow-on current SPD type 1 and 2 lightning current arrester A high-performance lightning current arrester for installations in LV cabling, at the boundary of the LPZ 0 LPZ 1 zones and higher levels, where no remote signalling is requi, and for protection against overvoltage effects in direct as well as indirect lightning strikes. It can be used in a variety of installations, suitable for family houses, administrative and commercial buildings, or in sub-distribution boards of large premises. It is specifi ed for single-phase TN-C networks. FLP-B+C MAXI V/1+1 I imp = 25 ka (10/350 µs) I n = 30 ka (8/20 µs) I max = 60 ka (8/20 µs) Zero leakage current No follow-on current SPD type 1 and 2 lightning current arrester A high-performance lightning current arrester for installations in LV cabling, at the boundary of the LPZ 0 LPZ 1 zones and higher levels, where no remote signalling is requi, and for protection against overvoltage effects in direct as well as indirect lightning strikes. It can be used in a variety of installations, suitable for family houses, administrative and commercial buildings, or in subsidiary distribution boards of large premises. It is specifi ed for single-phase TT networks. FLP-B+C MAXI V/2 I imp = 25 ka (10/350 µs) I n = 30 ka (8/20 µs) I max = 60 ka (8/20 µs) Zero leakage current No follow-on current SPD type 1 and 2 lightning current arrester A high-performance lightning current arrester for installations in LV cabling, at the boundary of the LPZ 0 LPZ 1 zones and higher levels, where no remote signalling is requi, and for protection against overvoltage effects in direct as well as indirect lightning strikes. It can be used in a variety of installations, suitable for family houses, administrative and commercial buildings, or in sub-distribution boards of large premises. It is specifi ed for single-phase TN-S networks. FLP-B+C MAXI V/3 I imp = 25 ka (10/350 µs) I n = 30 ka (8/20 µs) I max = 60 ka (8/20 µs) Zero leakage current No follow-on current SPD type 1 and 2 lightning current arrester A high-performance lightning current arrester for installations in LV cabling, at the boundary of the LPZ 0 LPZ 1 zones and higher levels, where no remote signalling is requi, and for protection against overvoltage effects in direct as well as indirect lightning strikes. It can be used in a variety of installations, suitable for family houses, administrative and commercial buildings, or in sub-distribution boards of large premises. It is specifi ed for three-phase TN-C networks. FLP-B+C MAXI V/3+1 I imp = 25 ka (10/350 µs) I n = 30 ka (8/20 µs) I max = 60 ka (8/20 µs) U p 1.5 kv Zero leakage current No follow-on current SPD type 1 and 2 lightning current arrester A high-performance lightning current arrester for installations in LV cabling, at the boundary of the LPZ 0 LPZ 1 zones and higher levels, where no remote signalling is requi, and for protection against overvoltage effects in direct as well as indirect lightning strikes. It can be used in a variety of installations, suitable for family houses, administrative and commercial buildings, or in sub-distribution boards of large premises. It is specifi ed for three-phase TT networks. 36

37 Practical Guide - Low-voltage power systems Lightning current arresters Combined lightning current arresters SPD type 1+2 FLP-B+C MAXI V/4 I imp = 25 ka (10/350 µs) I n = 30 ka (8/20 µs) I max = 60 ka (8/20 µs) Zero leakage current No follow-on current SPD type 1 and 2 lightning current arrester A high-performance lightning current arrester for installations in LV cabling, at the boundary of the LPZ 0 LPZ 1 zones and higher levels, where no remote signalling is requi, and for protection against overvoltage effects in direct as well as indirect lightning strikes. It can be used in a variety of installations, suitable for family houses, administrative and commercial buildings, or in sub-distribution boards of large premises. It is specifi ed for three-phase TN-S networks. FLP-B+C MAXI VS/1 I imp = 25 ka (10/350 µs) I n = 30 ka (8/20 µs) I max = 60 ka (8/20 µs) Zero leakage current No follow-on current SPD type 1 and 2 lightning current arrester A high-performance lightning current arrester for installations in LV cabling, at the boundary of the LPZ 0 LPZ 1 zones and higher levels, where remote signalling is requi, and for protection against overvoltage effects in direct as well as indirect lightning strikes. It can be used in a variety of installations, suitable for family houses, administrative and commercial buildings, or in sub-distribution boards of large premises. It is specifi ed for single-phase TN-C networks. FLP-B+C MAXI VS/1+1 I imp = 25 ka (10/350 µs) I n = 30 ka (8/20 µs) I max = 60 ka (8/20 µs) Zero leakage current No follow-on current SPD type 1 and 2 lightning current arrester A high-performance lightning current arrester for installations in LV cabling, at the boundary of the LPZ 0 LPZ 1 zones and higher levels, where remote signalling is requi, and for protection against overvoltage effects in direct as well as indirect lightning strikes. It can be used in a variety of installations, suitable for family houses, administrative and commercial buildings, or in sub-distribution boards of large premises. It is specifi ed for single-phase TT networks. FLP-B+C MAXI VS/2 I imp = 25 ka (10/350 µs) I n = 30 ka (8/20 µs) I max = 60 ka (8/20 µs) Zero leakage current No follow-on current SPD type 1 and 2 lightning current arrester A high-performance lightning current arrester for installations in LV cabling, at the boundary of the LPZ 0 LPZ 1 zones and higher levels, where remote signalling is requi, and for protection against overvoltage effects in direct as well as indirect lightning strikes. It can be used in a variety of installations, suitable for family houses, administrative and commercial buildings, or in sub-distribution boards of large premises. It is specifi ed for single-phase TN-S networks. FLP-B+C MAXI VS/3 I imp = 25 ka (10/350 µs) I n = 30 ka (8/20 µs) I max = 60 ka (8/20 µs) Zero leakage current No follow-on current SPD type 1 and 2 lightning current arrester A high-performance lightning current arrester for installations in LV cabling, at the boundary of the LPZ 0 LPZ 1 zones and higher levels, where remote signalling is requi, and for protection against overvoltage effects in direct as well as indirect lightning strikes. It can be used in a variety of installations, suitable for family houses, administrative and commercial buildings, or in sub-distribution boards of large premises. It is specifi ed for three-phase TN-C networks. 37

38 Lightning current arresters Combined lightning current arresters SPD type 1+2 FLP-B+C MAXI VS/3+1 I imp = 50 ka (10/350 µs) I n = 50 ka (8/20 µs) I max = 100 ka (8/20 µs) Zero leakage current No follow-on current SPD type 1 and 2 lightning current arrester A high-performance lightning current arrester for installations in LV cabling, at the boundary of the LPZ 0 LPZ 1 zones and higher levels, where remote signalling is requi, and for protection against overvoltage effects in direct as well as indirect lightning strikes. It can be used in a variety of installations, suitable for family houses, administrative and commercial buildings, or in sub-distribution boards of large premises. It is specifi ed for three-phase TT networks. FLP-B+C MAXI VS/4 I imp = 50 ka (10/350 µs) I n = 50 ka (8/20 µs) I max = 100 ka (8/20 µs) Zero leakage current No follow-on current SPD type 1 and 2 lightning current arrester A high-performance lightning current arrester for installations in LV cabling, at the boundary of the LPZ 0 LPZ 1 zones and higher levels, where remote signalling is requi, and for protection against overvoltage effects in direct as well as indirect lightning strikes. It can be used in a variety of installations, suitable for family houses, administrative and commercial buildings, or in sub-distribution boards of large premises. It is specifi ed for three-phase TN-S networks. Varistor lightning arresters SPD type 1+2 FLP-12,5 V/1(S) I imp = 12.5 ka (10/350 µs) I n = 30 ka (8/20 µs) I max = 60 ka (8/20 µs) U p 1.2 kv Optional remote signalling (S) SPD type 1 and 2 lightning current arrester A varistor lightning current arrester specifi ed for installations in LV cabling at the boundary of the LPZ 0 LPZ 1 zones and higher levels. It is used to protect against the effects of partial lightning strike currents, induced overvoltage in lightning strikes and against switching overvoltage. It is suitable for III and IV risk class buildings, in sub-distribution boards of large premises or the protection of air conditioners or heating cables. It is specifi ed for single-phase TN-C networks. FLP-12,5 V/1(S)+1 I imp = 12.5 ka (10/350 µs) I n = 30 ka (8/20 µs) I max = 60 ka (8/20 µs) U p 1.2 kv Optional remote signalling (S) SPD type 1 and 2 lightning current arrester A varistor lightning current arrester specifi ed for installations in LV cabling at the boundary of the LPZ 0 LPZ 1 zones and higher levels. It is used to protect against the effects of partial lightning strike currents, induced overvoltage in lightning strikes and against switching overvoltage. It is suitable for III and IV risk class buildings, in subsidiary distribution boards of large premises or the protection of air conditioners or heating cables. It is specifi ed for single-phase TT networks. FLP-12,5 V/2(S) I imp = 12.5 ka (10/350 µs) I n = 30 ka (8/20 µs) I max = 60 ka (8/20 µs) U p 1.2 kv Optional remote signalling (S) SPD type 1 and 2 lightning current arrester A varistor lightning current arrester specifi ed for installations in LV cabling at the boundary of the LPZ 0 LPZ 1 zones and higher levels. It is used to protect against the effects of partial lightning strike currents, induced overvoltage in lightning strikes and against switching overvoltage. It is suitable for III and IV risk class buildings, in sub-distribution boards of large premises or the protection of air conditioners or heating cables. It is specifi ed for single-phase TN-S networks. 38

39 Practical Guide - Low-voltage power systems Lightning current arresters Varistor lightning current arresters SPD type 1+2 FLP-12,5 V/3(S) I imp = 12.5 ka (10/350 µs) I n = 30 ka (8/20 µs) I max = 60 ka (8/20 µs) U p 1.2 kv Optional remote signalling (S) SPD type 1 and 2 lightning current arrester A varistor lightning current arrester specifi ed for installations in LV cabling at the boundary of the LPZ 0 LPZ 1 zones and higher levels. It is used to protect against the effects of partial lightning strike currents, induced overvoltage in lightning strikes and against switching overvoltage. It is suitable for III and IV risk class buildings, in subsidiary distribution boards of large premises or the protection of air conditioners or heating cables. It is specifi ed for three-phase TN-C networks. FLP-12,5 V/3(S)+1 I imp = 12.5 ka (10/350 µs) I n = 30 ka (8/20 µs) I max = 60 ka (8/20 µs) U p 1.2 kv Zero leakage current No follow-on current SPD type 1 and 2 lightning current arrester A varistor lightning current arrester specifi ed for installations in LV cabling at the boundary of the LPZ 0 LPZ 1 zones and higher levels. It is used to protect against the effects of partial lightning strike currents, induced overvoltage in lightning strikes and against switching overvoltage. It is suitable for III and IV risk class buildings, in sub-distribution boards of large premises or the protection of air conditioners or heating cables. It is specifi ed for three-phase TT networks. FLP-12,5 V/4(S) I imp = 12.5 ka (10/350 µs) I n = 30 ka (8/20 µs) I max = 60 ka (8/20 µs) U p 1.2 kv Optional remote signalling (S) SPD type 1 and 2 lightning current arrester A varistor lightning current arrester specifi ed for installations in LV cabling at the boundary of the LPZ 0 LPZ 1 zones and higher levels. It is used to protect against the effects of partial lightning strike currents, induced overvoltage in lightning strikes and against switching overvoltage. It is suitable for III and IV risk class buildings, in sub-distribution boards of large premises or the protection of air conditioners or heating cables. It is specifi ed for three-phase TN-S networks. Coordination impedance RTO-xxx I L (xxx) = 16; 35; 63 A U n = 500 V AC L = 10 µh Surge separating inductors Coupling impedance to secure proper coordination of an SPD if the minimum distance between an SPD type 1 and SPD type 2, which exceeds 10 m, is not maintained, or an SPD type 2 and 3, which exceeds 5 m. RTO-16 RTO-35 RTO-63 39

40 Surge arresters SLP-275 V/1(S) I n = 20 ka (8/20 µs) I max = 40 ka (8/20 µs) U p 1.2 kv Optional remote signalling (S) SPD type 2 surge arrester Varistor surge protection specifi ed for installations in LV cabling, particularly in sub-distribution boards. It is used to protect cabling and equipment against the effects of induced overvoltage in lightning strikes and against switching overvoltage. It is specifi ed for single-phase TN-C networks. SLP-275 V/1(S)+1 I n = 20 ka (8/20 µs) I max = 40 ka (8/20 µs) U p 1.2 kv Optional remote signalling (S) SPD type 2 surge arrester Varistor surge protection specifi ed for installations in LV cabling, particularly in sub-distribution boards. It is used to protect cabling and equipment against the effects of induced overvoltage in lightning strikes and against switching overvoltage. It is specifi ed for single-phase TN-S and TT networks. SLP-275 V/2(S) I n = 20 ka (8/20 µs) I max = 40 ka (8/20 µs) U p 1.2 kv SPD type 2 surge arrester Varistor surge protection specifi ed for installations in LV cabling, particularly in sub-distribution boards. It is used to protect cabling and equipment against the effects of induced overvoltage in lightning strikes and against switching overvoltage. It is specifi ed for three-phase TN networks. Optional remote signalling (S) SLP-275 V/3(S) I n = 20 ka (8/20 µs) I max = 40 ka (8/20 µs) U p 1.2 kv Optional remote signalling (S) SPD type 2 surge arrester Varistor surge protection specifi ed for installations in LV cabling, particularly in sub-distribution boards. It is used to protect cabling and equipment against the effects of induced overvoltage in lightning strikes and against switching overvoltage. It is specifi ed for three-phase TN-C networks. SLP-275 V/3(S)+1 I n = 20 ka (8/20 µs) I max = 40 ka (8/20 µs) U p 1.2 kv Optional remote signalling (S) SPD type 2 surge arrester Varistor surge protection specifi ed for installations in LV cabling, particularly in sub-distribution boards. It is used to protect cabling and equipment against the effects of induced overvoltage in lightning strikes and against switching overvoltage. It is specifi ed for three-phase TT networks. 40

41 Practical Guide - Low-voltage power systems Surge arresters SLP-275 V/4(S) I n = 20 ka (8/20 µs) I max = 40 ka (8/20 µs) U p 1.2 kv Optional remote signalling (S) SPD type 2 surge arrester Varistor surge protection specifi ed for installations in LV cabling, particularly in sub-distribution boards. It is used to protect cabling and equipment against the effects of induced overvoltage in lightning strikes and against switching overvoltage. It is specifi ed for three-phase TN-S networks. SLP-xxx V/1(S) xxx - other voltages U n(xxx) = 75, 150, 385, 440, 600 V AC I n = ka (8/20 µs) I max = 40 ka (8/20 µs) SPD type 2 surge arrester Varistor surge protection specifi ed for installations in LV cabling, particularly in sub-distribution boards. It is used to protect cabling and equipment against the effects of induced overvoltage in lightning strikes and against switching overvoltage. The SLP-600 V version is specifi ed for the protection of wind turbines and inventor equipment. Optional remote signalling (S) SLP-275 VB/1(S) I n = 20 ka (8/20 µs) I max = 25 ka (8/20 µs) U p 1.2 kv Optional remote signalling (S) No leakage current SPD type 2 surge arrester It is used to protect cabling and equipment against the effects of induced overvoltage in lightning strikes in areas with more frequent storms, and against switching overvoltage, or to protect measurement circuits as the fi rst level of protection. It is also suitable for installations in communications (M&C) circuits at the boundary of the LPZ 0 and LPZ 1 zones. SLP-275 VB/3(S)+1 I n = 20 ka (8/20 µs) I max = 25 ka (8/20 µs) U p 1.2 kv Optional remote signalling (S) No leakage current SPD type 2 surge arrester It is used to protect cabling and equipment against the effects of induced overvoltage in lightning strikes in areas with more frequent storms, and against switching overvoltage, or to protect measurement circuits as the fi rst level of protection. It is also suitable for installations in communications (M&C) circuits at the boundary of the LPZ 0 and LPZ 1 zones. SLP-xxx VB/1(S) xxx - other voltages U n = (xxx) = 75, 130 V AC I n = ka (8/20 µs) I max = 40 ka (8/20 µs) Optional remote signalling (S) No leakage current SPD type 2 surge arrester It is used to protect cabling and equipment against the effects of induced overvoltage in lightning strikes in areas with more frequent storms and against switching overvoltage or to protect measurement circuits as the fi rst level of protection. It is also suitable for installations in communications (M&C) circuits at the boundary of the LPZ 0 and LPZ 1 zones. 41

42 Surge arresters to DIN rail DA-275 V/1 (S)+1 U C 230 V AC I n = 5 ka (8/20 µs) U OC = 10 kv AC Optional remote signalling (S) SPD type 3 surge arrester A combination of varistor surge protection and an enapsulated spark gap connected in the 1+1 mode. Specifi ed for installations in LV cabling, at the boundary of the LPZ 2 and LPZ 3 zones. It is used to protect cabling and equipment against the effects of induced overvoltage in lightning strikes and against switching overvoltage. It is located as close as possible to the protected equipment. DA-275 V/3 (S)+1 U C 230 V AC I n = 5 ka (8/20 µs) U OC = 10 kv AC Optional remote signalling (S) SPD type 3 surge arrester A combination of three-pole varistor surge protection and an encapsulated spark gap connected in the 3+1 mode. It is specifi ed for installations in LV cabling, at the boundary of the LPZ 2 a LPZ 3 zones. It is used to protect cabling and equipment against the effects of induced overvoltage in lightning strikes and against switching overvoltage. It is located as close as possible to the protected equipment. DA-275 DJ U C 230 V AC I n = 5 ka (8/20 µs) U OC = 10 kv AC SPD type 3 surge arrester A surge arrester for universal use to protect all types of LV electrical and electronic equipment against surge overvoltage. It is specifi ed for mounting in all types of systems (TN-S, TT, TN-C, IT). Visual status signalling (S) DA-xxx DJ xxx - other voltages U C (xxx) = 75; 130 V AC I n = 4 5 ka (8/20 µs) U oc = 8 10 kv AC SPD type 3 surge arrester A surge arrester for universal use to protect all types of LV electrical and electronic equipment against surge overvoltage. Visual status signalling (S) Socket outlet DA socket outlet U c = 275 V AC Visual or acoustic status signalling SPD type 3 surge arrester A socket with surge protection should be mounted close to the protected equipment or at the boundary of the LPZ 2 and LPZ 3 zones. Supplied surge arresters: protected sockets in versions Classic, Tango, Time, Element, Profi l 45, Refl ex SI, Praktik socket adapters in combination with protection of telephone ISDN, data line or antenna conductor bar multiple sockets for 19" stands 42

43 Practical Guide - Low-voltage power systems Surge arresters with RFI filter DA-275 DF xxx (S) I L (xxx) = 2; 6; 10; 16; 25 A U OC = 10 kv SPD type 3 surge arrester A surge arrester with an integrated RFI fi lter to protect the supply of control systems such as M&C, ESS, EFS, etc., against surge overvoltage and RFI disturbance. Optional remote signalling (S) No remote signalling available for DA-275 DF 25 DA-275 DFI xxx I L (xxx) = 1; 6; 10; 16 A U OC = 3-10 kv SPD type 3 surge arrester A surge arrester with an integrated RFI fi lter to protect the supply of control systems such as M&C, ESS, EFS, etc., against surge overvoltage and RFI disturbance. DA-275 DF 25 I L = 20 A U OC = 10 kv SPD type 3 surge arrester A surge arrester with an integrated RFI fi lter to protect the supply of control systems such as M&C, ESS, EFS, etc., against surge overvoltage and RFI disturbance. DA-400 DF 16 (S) I L = 16 A U n = 400 V AC U OC = 10 kv U p 1.4 kv SPD type 3 surge arrester A surge arrester with an integrated RFI fi lter to protect the supply of control systems such as M&C, ESS, EFS, etc., against surge overvoltage and RFI disturbance for two-phase supply. Optional remote signalling (S) DA-275 BFG I L = 16 A U OC = 10 kv U p 15 kv SPD type 3 surge arrester A surge arrester with an integrated RFI fi lter to protect the supply of control systems such as M&C, ESS, EFS, etc., against surge overvoltage and RFI disturbance. 43

44 Surge arresters For additional mounting CZ-275 A I n = 3 ka (8/20 µs) U OC = 6 kv SPD type 3 surge arrester Surge arresters for additional mounting in appliances, devices, machines, equipment, etc., specifi ed to protect all types of LV electrical and electronic equipment against surge overvoltage. CZ-275 A - Acoustic status signalling DA-275 CZS I n = 3 ka (8/20 µs) U OC = 6 kv SPD type 3 surge arrester Surge arresters for additional mounting in appliances, devices, machines, equipment, etc., specifi ed to protect all types of LV electrical and electronic equipment against surge overvoltage. Remote signalling is potential-free break contact DA-275 A I n = 2 ka (8/20 µs) U OC = 4 kv AC Acoustic status signalling SPD type 3 surge arrester Surge arresters for additional mounting in appliances, devices, machines, equipment, etc., specifi ed to protect all types of LV electrical and electronic equipment against surge overvoltage. It is suitable for single-phase supply networks, without the need to comply with the connection of the L, N conductors in the installation. It can also be used for single-phase supply networks with a separating transformer. DA-275 S I n = 2 ka (8/20 µs) U OC = 4 kv AC Status remote signalling SPD type 3 surge arrester Surge arresters for additional mounting in appliances, devices, machines, equipment, etc., specifi ed to protect all types of LV electrical and electronic equipment against surge overvoltage. It is suitable for single-phase supply networks, without the need to comply with the connection of the L, N conductors in the installation. It can also be used for single-phase supply networks with a separating transformer. Others ISG-A100 I imp = 100 ka (10/350 µs) Isolation resistance >100 kω classification H class Isolating spark gap It is used for the indirect connection of an external lightning protection system to other close metallic parts, where a direct connection is not allowed due to operating conditions: earthing systems of heavy current installations, telecommunications systems, auxiliary and rail earthing bars of earth short-circuit breakers trigge by the voltage, AC and DC rail earthing bars, measurement earthing bars for laboratories, installations with cathodic protection and stray current systems, service entry poles for external LV cables, by-pass of isolated fl anges and isolated connections to pipes. 44