White paper. RC223 (type B) residual-current release

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Gabriella Horn
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1 Whie paper (ype B) residual-curren release

3 (ype B) residual curren release Index 1. Generals Applicaion descripion Applicaions Applicaion examples How does an operae? Applicaion indicaions Technical characerisics Configuraion indicaions Emergency Arres (EA) Operaing ime and curren "Tesing field" secion...8 ABB (ype B) residual curren release 1

1. Generals The residual curren release, which can be combined wih he Tmax T3, T4 four-pole circui-breakers in he fixed or plug-in version, is he mos advanced soluion in he whole residual curren

4 1. Generals The residual curren release, which can be combined wih he Tmax T3, T4 four-pole circui-breakers in he fixed or plug-in version, is he mos advanced soluion in he whole residual curren release family for he Tmax range. I can boas conformiy wih Type B operaion, which guaranees sensiiviy o residual faul currens wih alernaing, alernaing pulsaing and direc curren componens. Apar from he signals and seings ypical of he basic residual curren release, also allows he selecion of he maximum hreshold of sensiiviy a he residual faul frequency (3 seps Fe = Hz). I is herefore possible o adap he residual curren device o he differen requiremens of he indusrial plan according o he prospecive faul frequencies generaed on he load side of he release. Sinusoidal ac Form of residual curren suddenly applied slowly rising suddenly applied Correc funcioning of residual curren devices Type AC A B Pulsaing dc wih or wihou A + + slowly rising Smooh dc + 2 (ype B) residual curren release ABB

5 2. Applicaion Descripion 2.1 Applicaions Single-phase user devices, such as uninerrupible power supplies (UPS), PCs, priners, cash regisers, elecro medical equipmen ec. mouning elecronic circuis in alernaing curren, in case of earh faul, generae currens wih direc componens. Analogously, hree-phase users as, for insance, UPS, compued omography (CT) equipmen, nuclear magneic resonance (MR) equipmen, variable speed drives and AC/DC converers in case of earh fauls, generae such direc currens ha he funcioning of he residual curren devices (RCDs) placed o proec he relevan supply circuis could be jeopardized. In hese cases, since hese faul currens o earh are no necessarily deeced by he oroid of ype AC residual curren devices, ype A residual curren devices are chosen for singlephase users and ype B for hree-phase users. In fac, in case here is a hree-phase drive (consiued by a recifier and an inverer as shown in he figure) o run an asynchronous moor a variable speed, he earh faul can occur boh in he direc curren secion as well as in he secion on he load side of he inverer. In his las case, high frequency earh faul currens are generaed wih high harmonic conen; herefore hey can be deeced only by a ype B residual curren device. In phoovolaic insallaions, if he PV supply sysem does no have a leas a simple segregaion beween he AC side and he DC side, he residual curren device insalled o provide proecion agains indirec conacs by means of auomaic ripping shall be of ype B (IEC ). Analogously, he Sandard E prescribes ha proecion of UPS agains earh fauls is carried ou by residual curren circui-breakers of ype B (for hree-phase UPS) and of ype A (for single-phase UPS) when he UPS projec conemplaes he possibiliy of an earh faul curren wih direc curren componens. Besides, given a mobile elecronic equipmen wih power > 4 kva or a fixed one generaing a reduced-ripple faul direc curren, when a residual curren device is used for he proecion agains direc and indirec conacs, on he supply side of he apparaus iself exclusively he use of a ype B RCD (E 50178) is acceped. Therefore, a residual curren device ype B is used for ripping (see IEC/TR60755): as a ype A (sinusoidal currens a Hz and unidirecional pulsaing currens); for residual alernaing currens superimposed on a smooh direc curren of 0.4 imes he raed residual curren IΔn; for residual pulsaing currens superimposed on a smooh direc curren of 0.4 imes he raed residual curren IΔn or 10mA, whichever is he highes value; for residual currens which may resul from recifying circuis, i.e.: 1. wo-pulse bridge connecion line o line for 2-, 3- and 4-pole devices; 2. single-phase bridge conneced o a capaciive load, deermining pulsaing smooh direc currens; 3. hree-pulse sar connecion or six-pulse bridge connecion for 3- and 4-pole devices; for residual smooh direc currens. Recifier Inverer (A) 0.3 RCD Moor M R B If (s) ABB (ype B) residual curren release 3

2. Applicaion Descripion 2.2 Applicaion examples Type B proecion required o be applied in medical equipmen, pipe heaing sysem, frequency ransducer, elevaor conrolling, ec.

6 2. Applicaion Descripion 2.2 Applicaion examples Type B proecion required o be applied in medical equipmen, pipe heaing sysem, frequency ransducer, elevaor conrolling, ec. DC Iu up o 250A Ue up o 500Vac F = 50/60Hz Welding Plans for Auomoive Indusry (1000Hz) Fe=1000Hz Frequency Convering Sysem Texile Indusry (700Hz) Fe=700Hz Airpors and Three-Phase Drives (400Hz) 4 (ype B) residual curren release ABB Fe=400Hz

7 The following able shows some ypical applicaions wih power elecronics, where ype B residual curren devices can be used; in paricular, hey are necessary in he examples because of he predominan presence of he direc componen which could no be deeced by ype A-AC residual curren devices. Connecion ormal mains curren Earh faul curren A or B RC221 RC222 1 Single-phase B 2 Single-phase wih smoohing B 3 Three-phase sar A or B RC221 RC222 4 Two-pulse bridge A or B RC221 RC222 5 Two-pulse bridge, half-conrolled B 6 Two-pulse bridge beween phases B 7 Six-pulse bridge AC or A or B RC221 RC222 8 Phase conrol AC or A or B RC221 RC222 9 Burs conrol ABB (ype B) residual curren release 5

8 2. Applicaion Descripion 2.3 How does an operae? All he acive conducors of he supply circui o be moniored (excep for he proecion conducor) are encircled by he residual curren oroid, as in ype AC and A residual curren devices. everheless, in ype B residual curren devices ype, keeping a single oroid, a special mehod of operaion and measuring is used for he deecion of direc and alernaing currens. The oroid is no more used passively, by reading only he curren induced as in he case of ypes AC and A, bu i is supplied by a volage wih recangular waveform and khz frequency. Such volage generaes in he winding an alernaing curren whose waveform is shown in he figure below. A resisance in series wih he winding creaes a volage drop, whose value is sen o a microprocessor including a low-pass filer. If here is a faul residual curren, i shall cause a variaion of he waveform of he curren deeced as i can be seen in he figure below. The specrum of such waveform shall be herefore formed by some lines a he fundamenal frequency and a is muliples and some lines a he faul frequency. By low-pass filering i will be possible o deec he faul componen even if i is direc (ype B) residual curren release ABB

9 3. Applicaion Indicaions 3.1 Technical characerisics Size Type T3 and T4 4p Primary service volage [V] Raed frequency [Hz] Earh faul frequency [Hz] Raed service curren [A] up o 250 A Trip hreshold - raed residual curren [A] Time limi for non-rip a 2 IΔn [s] ins Tolerance over rip ime ±20% Absorbed power 400V oe: for Tmax T3 CB has a limiaion in he raed curren equal o 225A, which is consequenly he maximum curren hreshold which can be se on he CB. The raed frequency is always Hz; by selecing Hz, he device becomes sensiive o he deecion of he faul currens up o hese frequencies. B 3.3 Emergency Arres (EA) residual curren device associaes o he residual curren proecions he emergency arres funcion for remoe opening. In comparison wih he devices commonly used in he emergency circuis, offers he advanages of a posiive safey (since he accidenal break of he circui is equivalen o an acion on he emergency pushbuon) and of absence of unwaned rips in case of reducion or emporary inerrupion of he nework volage. The acion on he emergency buon conneced o he residual curren device causes a variaion of he logic level which is read by he microprocessor conrolling he shun opening release. 3.2 Configuraion indicaions ED: 7 blinks in 3.5s 6 blinks in 3s 5 blinks in 3s 3 blinks in 2.5s 1 blink in 2.5s ligh fixed coninuos blinking Inernal supply error Curren sensor error YO2 broken cable or YO2 wihou cable YO2 bloked SO open PreAlarm Alarm or CB ripped max For insallaion and more informaion please refer o he indicaions of RC22X (1SDH000436R0507) Pre-Alarm: When he residual faul curren urns up and he value is higher han 25% of he seup hreshold I Δn, he ED is li up fixed. Alarm (Trip): When he residual faul curren value is higher han 75% of he seup hreshold I Δn (wih I Δn =0.03A for human proecion, he faul should be higher han 90% of he seup one), he ED blinks, and he opening release conneced o will rip according o he seup ime delay s(s). By seing I Δn and (non-rip ime) i is possible o achieve ime-curren seleciviy wih oher devices in series. However, seing a raed residual curren of 30mA, he inenional delay is null (as indicaed in he Sd. IEC Annex B) since i can be used also as addiional proecion agains direc conac. ABB (ype B) residual curren release 7

10 3. Applicaion Indicaions 3.4 Operaing ime and curren The following diagrams show he ripping imes of as a funcion of he residual curren and aking as parameer he ime delay se; he ripping imes are useful above all whenever wishing o carry ou a seleciviy sudy beween residual curren devices. Maximum ripping ime [ms] [ms] Id/Idn Id/Idn Ins 0.1s 0.2s 0.3s 0.5s 1s 2s 3s 3.5 Tesing field secion According o he Sd. IEC (clause ), he circuis incorporaing solid-sae devices conneced o he main circui shall be disconneced from he supply for he es of he dielecric properies of he circui-breaker. In case of he, his device has o be disconneced before he es and conneced again afer i as shown in he following figure. The insulaion es is carried ou wih he rip coil disconneced. Insulaion es O TEST Insulaion Tes 700 POWER AARM TRIPD Back o service saus r. CACK I n (A) (s) IEC Ue = V Imax = 250A O TEST Insulaion Tes f(hz) IEC Ue = V Imax = 250A CACK IEC Ue = V Imax = 250A O TEST Insulaion Tes r. POWER AARM TRIPD I n (A) (s) O TEST Insulaion Tes f(hz) IEC Ue = V Imax = 250A Push 8 (ype B) residual curren release ABB

12 Conac us ABB SACE A division of ABB S.p.A..V. Breakers Via Baioni, Bergamo - Ialy Tel.: Fax: The daa and illusraions are no binding. We reserve he righ o modify he conens of his documen on he basis of echnical developmen of he producs, wihou prior noice. Copyrigh 2009 ABB. All righs reserved. 1SDC007404G /2009

Special Insert. Everything you wanted to know about Type B residual current circuit breakers but never dared to ask

Special Insert. Everything you wanted to know about Type B residual current circuit breakers but never dared to ask Special Inser Everyhing you waned o know abou Type B residual curren circui breakers bu never dared o ask Claudio Amadori: R&D ABB 1 Figure 1 - Marking of he Type B residual curren circui breakers Type