VAMP Ltd
Feeder and motor manager
Technical description
VAMP 257
VM257.EN002
VAMP 24h support phone : +358 (0)20 753 3264
109
3.5.2.
Trip circuit supervision with one digital input
•
The digital input is connected parallel with the trip contacts
(Figure 3.5.2-1).
•
The digital input is configured as Normal Closed (NC).
•
The digital input delay is configured longer than maximum
fault time to inhibit any superfluous trip circuit fault alarm
when the trip contact is closed.
•
The trip relay should be configured as non-latched.
Otherwise, a superfluous trip circuit fault alarm will follow
after the trip contact operates, and the relay remains closed
because of latching.
CB
CLOSE COIL
OPEN COIL
close control
trip circuit
failure alarm
R1
-V
AUX
+V
AUX
-V
AUX
VAMP 257 terminal
Digital input
Trip relay
Alarm relay
for trip
circuit failure
relay compartment
circuit breaker compartment
TripCircuitSupervisionFor257
Figure 3.5.2-1. Application example when one of digital inputs 7…32 is used
for trip circuit supervision. Trip circuit supervision when the circuit-breaker
is closed. The supervised circuitry in this CB position is double-lined. The
digital input is in active state. For the application to work when the circuit-
breaker is opened, a resistor R1 must be placed. The value for it can be
calculated from the external wetting supply, so that the current over R1 is
>1 mA.
