EasyGrid LT User Guide
27
System relay
5.4
The EasyGrid LT System relay tells you if the EasyGrid LT and his sensors are working properly. This relay
is of failsafe type.
Failsafe operation means that when in alarm, the relay contacts are in their "normal," de-energized, or
"shelf-state" positions. In other words, normally closed relays contacts are closed in alarm, and normally
open relays contacts are open in alarm.
The following conditions will give an alarm on the system relay (the relay close the circuit between the
common (C) and the normally close(NC) terminal):
- power failure, or
- invalid reading of an active temperature channel, or
- internal error of the EasyGrid LT , or
- EasyGrid LT WatchDog time out
At power up the EasyGrid LT system relay is in alarm until all the actives sensors gives valid reading, it
could take up to 1minute (depending on the number of active channels) for the alarm condition to
resume.
When the EasyGrid LT is in good working condition, the system relay closes the circuit between the
common (C) and the normally open (NO) terminals.
Systems relay Ratings: 1.5A @ 30VDC / 1A @ 120VAC / 0.5A @ 250VAC
