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IRDH375_D00124_05_M_XXEN/01.2020
5. Connection
5.1 Wiring
IRDH375(B) has plug-in terminals.
Connect the terminals "A1/+" and "A2/-" to the supply voltage U
S
in accord-
ance with IEC 60364-4-43. The connections to the supply voltage shall be pro-
vided with protective devices to afford protection in the event of a short
circuit (a 6 A fuse is recommended).
For UL and CSA applications, the use of 5 A fuses is mandatory.
Devices for protection against short-circuit in conformity with
IEC 60364-4-43 for the IT system coupling L1/L2 can be omitted if the wiring is
carried out in such a manner as to reduce the risk of a short-circuit to a mini-
mum (a short-circuit-proof and earth-fault-proof wiring is recommended).
Only one ISOMETER® may be triggered by an external TEST or RESET button. A
galvanic parallel connection of several Test and Reset inputs for common test-
ing of ISOMETER® is not permitted.
External coupling devices connected via the terminal AK cannot be switched
off via the internal coupling relays. If no coupling device is used, the terminal
AK remains free.