Siemens SENTRON 3VA2 - External Current Transformer for N Conductor; Parameterization of the External N Transformer

Accessories
4.12 External current transformer for N conductor
3VA molded case circuit breakers with IEC certificate
Manual, 03/2019, A5E03603177010-03
525
4.12
External current transformer for N conductor
The external current transformer for the N conductor is a current transformer for 3-pole 3VA2
molded case circuit breakers with 5-series and 8-series ETUs.
This transformer can be used to provide protection for the N conductor against overload as
well as for ground-fault protection.
4.12.1
Parameterization of the external N transformer
N conductor protection against overload
The function "N conductor protection I
N
" is deactivated ("OFF") as standard (factory setting)
in 5-series and 8-series ETUs.
If an external N transformer is connected to 5-series or 8-series ETUs, the "N conductor
protection I
N
" must be manually activated on the ETU and adjusted according to system
requirements.
Ground-fault protection
If the external N conductor is used with 5-series or 8-series ETU variants with ground-fault
protection, ETU560 and ETU860, no parameterization is required at the user end. As soon
as the external N transformer is connected to the ETU, the N conductor is also automatically
monitored for ground-fault protection.