Datasheet

ESG 7.12
Function description
Phase sequence monitoring
When all the phases are connected in the correct sequence and the
measured asymmetry is less than the fixed value, the output relay
switches into on-position (yellow LED illuminated). When the phase
sequence changes, the output relay switch into off-position (yellow
LED not illuminated).
Phase failure monitoring
The output relay switches into off-position (yellow LED not illumina-
ted), when one of the three phases fails.
Asymmetry monitoring
The output relay R switches into off-position (yellow LED not illumi-
nated) when the asymmetry exceeds the value set at the ASYM-
regulator.
Reverse voltages of a consumer (e.g. a motor which continues to run
on two phases only) do not effect the disconnection.
3-phase voltage monitoring relay
EMR IU11D1, IU21D1
LED U
L1 L2 L3 L1 L3 L2
LED U
L1
L2 L3
LED U
L1
L2 L3
Asym.