Sepam - HV/MV Protection and control units (ENG) - Trinet

InstallationUse and connection of CSH 120 and CSH 200 core balance CTsCSH 120 and CSH 200core balance CTsThe specific CSH 120 and CSH 200 core balanceCTs are used for direct measurement of earth faultcurrent. The only difference between them is theirinner diameter and they operate with 2 input ratings:c 2 A input rating:settings from 0.1 A to 20 A,c 30 A input rating:settings from 1.5 to 300 A.Due to the CSHs’ low voltage isolation,they may only be used on cables.300 A100 A80 A50 ACSH 20030 A corebalanceCSH 120 CT ratingI mm2 Ω 10 ΩCharacteristics:c inner diameter:v CSH 120 : ø 120 mm,v CSH 200 : ø 200 mm.c accuracy: ±5%,c transformer ratio: 1/470,c maximum permissible current: 20kA-1 second,c operating temperature: - 25 °C to +70 °C,c storage temperature: - 40 °C to +85 °C,c maximum metering current I mm.This is a current value beyond which the SepamCSH core balance assembly saturates.The user must therefore be careful not to set thetripping threshold higher than I mm.The maximum metering current depends on:v chosen rating (2 A or 30 A core balance CT),v core balance CT used (CSH 120 or CSH 200),v wiring resistance Rw back and forth between thecore balance CT and Sepam 2000.20 A0.1 Ω 1 ΩCSH 120CSH 200R W2 A corebalanceCT ratingThe graph above gives the value of I mmfor Rw < 10 Ω.This graph is used to choose the required core balance CT and wiring.Example: the high setting of the earth fault protection is 80 A.Therefore, the 30 A rating of Sepam 2000 is chosen (wiring to terminals 3 and 4of the earth fault connector).From the graph, it may be deduced that the CSH 120 and CSH 200 are suitableregardless of the wiring resistance, within the limit of 10 Ω.Dø 5 mountingCFHø AGKBSelection of operating mode(microswitches)c Set the SW1 microswitches on the Sepam 2000.The microswitches concerned are found on the inputmodule. They should be switched while the Sepam2000 is de-energized.The microswitches are hidden by the CCA 660 orCCA 650 connector once it has been installed.JLEdimensions (mm)weight (kg)A B C D E F G H J K LCSH 120120 164 26,5 44 190 76 52 40 166 62 35 0.6CSH 200200 256 28 46 274 120 90 60 257 104 37 1.4SW2SW1for measuring residual currentby a CSH core balance CT.1/16 Installation - Use - General characteristics - Testing