ERICO TSG Series Surge Reduction Filters (TSG-RSF) - Manual (Page 19)

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Connection of Alarm Circuits
6.5 CONNECTION OF ALARM
CIRCUITS
The TSG-SRF secondary surge diverters are
continuously monitored and their internal
protection status is identified by a two
segment LED indicator for each phase.
Reduction in surge handling capacity activates
a set of voltage free alarm contacts which
can be used to shut down the load or to
activate an external warning. Once an alarm
situation is registered, there is a three-second
delay prior to the alarm contacts opening.
This three-second alarm delay is provided to
eliminate the possibility of nuisance alarms
that may be attributed to brief supply voltage
variations.
When mains voltage is applied to the
TSG-SRF and the surge diverters are fully
functional, the alarm contacts will be in the
energised or normal state. The NC contact
will be in short circuit with the COM contact.
Should the surge handling capacity fall to
below the alarm threshold, these contacts will
be in the de-energised or alarm state and the
NO contact will be in short circuit with the
COM contact.
The contacts are "Fail-Safe" in that, if power
to the unit fails, the contacts will revert to the
de-energised or alarm state.
The alarm contacts should only be connected
by an appropriately qualified person owing to
the possibility of mains voltage being present
in the TSG-SRF cabinet. Care should be taken
to route the alarm wiring away from the
input circuit and any other current-carrying
conductors.
Alarm contact ratings:
• 2A @ 30Vdc
• 600mA @ 110Vdc
• 600mA @ 125Vac
E535IS06ENAS 10/6/06 11:12 AM Page 19