Information

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Voltage Monitoring (RPW/ERWM)
25
ERWM-VM1 / VM2
The ERWM controls the faults in the voltage monitoring within which a three-phase
supply voltage can operate. Whenever a failure in the power grid occurs, the relay will
switch its output in order to interrupt the operation of the monitored motor or process.
Installation
It is directly connected to the three phases (L1, L2 and L3) of the power grid to be
monitored (connect the neutral if applicable).
Selection
ERWM - VM1 - 01 - D90
Wiring Diagram
Specification
Reference Supply voltage
ERWM-VM1-01D90
208-480 V ac 50/0 Hz (L1-L2-L3)
ERWM-VM2-01D90
Electrical connection (VM1 / VM2)
L1 - L2 - L3 Supply voltage
N - A - B Voltage and neutral detection
15 - 16 / 18 Output contact
15 16 18
L1 L2 L3
ERWM
VM1/VM2
N A B
L1 L2 L3
N A B
16 18
15
WEG electronic
monitoring relay
Models:
VM1: PF-Phase loss, PS-Phase sequence, >Un-Overvoltage/<Un-Undervoltage, Asy-Unbalance, ND-Neutral Detection
VM2: PF-Phase loss, Un-Overvoltage/Undervoltage, Asy-Unbalance, ND-Neutral Detection
Number of
contacts
Supply
voltage
Operation
If the voltage on terminals L1, L2 and L3 is correct, the output relay is energized
(contacts 15-18 close). If the monitored supply voltage is in the adjusted operating
range, the output relay is de-energized (contacts 15-18 open). The output relay is
energized again when the voltage returns to an acceptable value.
Certifications