Drawout case alarm in 489 relay

Jorge Munoz,

When did this alarm become active? After the relay was withdrawn from the case?

If my memory serves me correctly, there is a switch or some kind of sensor (non-contact) that checks to see if the relay has been properly inserted/re-inserted into the case after is has been removed (withdrawn). If the relay was not properly inserted/re-inserted into the case then this alarm warns to user that the relay has not been properly installed/re-installed and my result in non-operation or intermittent operation or failure of the relay.

So, it's best to check to make sure the relay has been inserted/re-inserted per the instruction in the manual. I note the manual says the relay and case are keyed, so that if someone tries to insert a relay other than the one which was removed it should not be possible to do so. If a non-matching relay was inserted into a case and the latching mechanism was unduly forced that may also be part of the problem.

Again, this is from memory and it's been many years since I worked on a 489 Multilin relay. I don't recall if the drawout mechanism uses an actual switch (or microswitch) or if it uses some kind of non-contact sensor (like a magnet or something similar) to detect if the relay was properly inserted. It may just be that the latching mechanism actuates a switch or sensor when it is fully engaged in the latched-in position.

Please write back to let us know what you found.

(P.S. I had a read of a couple of the 489 manuals available on the World Wide Web, and they had zero information on this particular alarm function. Typical GE documentation.... )