Current transformers TI current transformers 0

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1 Current transformers TI current transformers NMD NMD Function Current transformers with a ratio of Ip/5, for measurement devices (ammeters, kilowatt hour meters), load shedders, control relays, etc. Common technical data b Secondary current: 5 A. b Max. voltage rating Ue: 720 V. b Frequency: Hz. b Safety factor: v 40 to 4000 A: fs y 5 v 5000 to 6000 A: fs y 10. b IP20. b Ambient installation temperature: v standard range: - 5 C to + 55 C, humidity < 95 % v tropicalised range: - 25 C to + 60 C, humidity > 95 %. b Reference standards: IEC 44-1, NFC42502, VDE 0414, BS 7626 and IEC b Weight: NMD Weight (g) and and and and and Specific technical data PB TI with let-through primary: b Secondary connection using terminals for lug, using tunnel terminals or using screws (depending on cat. no.). b Delivered with: fixing on a symmetrical rail fixing on a plate Insulated binding screw Sealable cover and b b b and b b b Optional and b b b Optional and b b b and b b b b b b b b b b MD-2 Sealable cover. b Maximum dimensions for primary circuit cable inlets: Opening Cable Ø and x 5 mm and x 10 mm and x 10 mm and x 11 mm and 51 x 31 mm and x 32 mm x 84 mm x 127 mm x 127 mm x 165 mm

2 Current transformers TI current transformers (cont.) 0 TI with connection of primary by screw and nut: b Secondary connection using terminals for lug or tunnel terminals (depending on cat. no.). b Cylinder Ø 8.5 mm. b Cylinder Ø 12.5 mm. b Delivered with: (1) Rigid flat. (2) Rigid vertical. (3) < 80 mm rigid. (4) 80 mm rigid. (5) 100 mm rigid. (6) 100 mm rigid triple. fixing on a symmetrical rail fixing on a plate Sealable cover and b b b and b b Optional TI with let-through primary Ratio Insulated Prisma cable vertical Insulated flexible Linergy vertical Rigid Cat. no. TI standard Cat. no. TI tropical 40/5 b /5 b /5 b /5 b /5 b b /5 b b b b /5 b b b b b /5 b b b b b /5 b b b b b /5 b b b b b /5 b b b b /5 b b (1) b b b (2) /5 b b b /5 b b b /5 b b b (3) b (4) b (5) /5 b (3) b (4) b (5) /5 b /5 b b (6) /5 b b (6) /5 b /5 b /5 b 16549

3 Current transformers TI current transformers (cont.) 0 TI with connection of primary by screw and nut Ratio Cat. no. TI standard Cat. no. TI tropical Cat. no. cylinder 40/ / or / or / or / or / or / or / or / or / or / or / or Accessories Type Cat. no. Cylinder Ø 8.5 mm Ø 12.5 mm Sealable cover for cat. nos to and to for cat. nos to and to Connection E56648 S1 S2 K L P1 K E56651 K P2 TI with let-through primary. E56646 E56647 S1 S2 K L P1 K S1 S2 K L P1 K TI with connection of primary by screw and nut.

4 Current transformers TI current transformers 0 Choice and accuracy class Choosing a current transformer 2 criteria exist for choosing a TI: b the Ip/5 A ratio b the type of installation. The Ip/5 A ratio It is recommended that a ratio immediately above the measured current (In) be chosen. Example: In = 1103 A; ratio chosen: 1250/5. Type of installation Which TI model to choose depends on the type of installation: b insulated cables b Prisma vertical b insulated flexible b Linergy vertical b rigid. Important warning Never open the secondary circuit of a current transformer while the primary circuit is energized. Before any kind of maintenance service on the secondary circuit, the secondary terminals on the tranformer must be short-circuited. Determining the accuracy class of a TI The accuracy class is a function of the transformer's power and the consumption of the measurement system. The latter takes device and cable consumption into account. For a given accuracy class, consumption of the measurement system must not exceed the power on the TI transformer. Copper cable cross-section in mm 2 Power in VA per doubled meter at 20 C For each temperation variation of 10 C, the power absorbed by the cables rises by 4 %. Merlin Gerin device Consumption in VA Ammeter 72 x 72 / 96 x Analog ammeter 1.1 Ammeter Digipact IM Digital ammeter 0.3 PM500, PM700, PM800, CM3000, CM CE tri 1.2 CEr tri 1.2 ME4zrt 0.05 PM9 0.55

5 Current transformers TI current transformers 0 Choice and accuracy class (cont.) Example: consumption of a measurement system at 20 C PM VA Digital ammeter VA 4 meters of doubled wire 2.5 mm VA Measurement system consumption = 2.19 VA The accuracy class of the TI is deduced: b class 3 for a TI with a ratio of 75/5 b class 1 for a TI with a ratio of 100/5 b class 0.5 for a TI with a ratio of 125/5. Ip/5 Cat. no. Power (VA) accuracy class standard TI tropical TI A A A A A A A A A A A A A A A A A A A A A A

6 Current transformers Dimensions 0 TI current transformers E58377 E58380 E58383 Cat. no to 16506, to Cat. no to 16515, to Cat. no to 16521, to E58376 E58379 E58382 Cat. no and 16524, and Cat. no to 16535, to Cat. no and E58375 E58378 E58381 Cat. no to Cat. no to Cat. no and Cylinders E90390 E90391 Cat. no Cat. no