We utilize the "Local Alarms" pin-outs on the backplane of one node and connect to an external alarm notification device (A simple relay, light and beeper system). We've been using this for 4-5 years.
Recently our alarm device is no longer being triggered when there is a Remote Alarm. The TCC2 card LED will indicate a "REM" alarm but both the Remote visual and audible contacts on the backplane will not close, triggering our alarm system. The minor, major, and critical contacts work as they are supposed to. We have reset the TCC2 card but this did not help. We upgraded to Release 8.5.1 about 2-3 months ago, and just noticed this problem a few weeks ago.
Is this a issue with Release 8.5.1 or is there some other problem(s) we could be experiencing?
You may be seeing bug CSCsu40460: external remote alarm relay is not set correctly. It is reported as being present as of 7.0 and Fixed-In 9.0(0)RT1.124 and 9.0(1)RP1.1
May you use a multimeter to confirm the issue stays on A1/B1 of Audible and Visual connectors and is not preset on A2-4/B2-4?
You can try as well to move your alarm device from A1/B1 to A2/B2 for example (Critical) to confirm the problem is not with the device itself and the issues always stays with A1/B1.
Re-seat the AIC card in the chassis to make sure it is properly seated. (Do you use AIC or AIC-I?).
Do you have another 15454 with an AIC? If so, swap the AIC between the nodes to verify if the problem follows the AIC or stay with the node.
The A2-B2 thru A4-B4 (local Critical, Major, Minor) contacts work fine and we never had a problem with those contacts. The A1-B1, VIS & AUD, "Remote" contacts do not change states when there is a remote alarm.
We do not have any AIC cards installed in any of our nodes.
As I stated in my original post, this alarm worked great for about 5 years until we upgraded to Release 8.5.1. The recent upgrade to Release 9.1 has not fixed the problem. The REM indicator on the TCC2 card does show a remote alarm, but the relay does not change.
I’ve just tested AIC and AIC-I with 9.1 and when there is a remote alarm I see the A1/B1 pair closes. I used a millimeter and measured 500ohm resistance when it is closed (Rem alarm is active) and infinity when it is opened .
May you try a multimeter and measure a resistance on A1/B1 for audio and video pins?
As you have a local access to the node, disable DCC channels, so there are no remote alarms (REM LED should go Off on TCC) and measure the resistance again.
Re-seat the AIC card in the chassis to make sure it is properly seated.
Move the AIC to another 15454 to verify if the problem follows the AIC or stay with the node. It may be an AIC or a chassis problem.
Ops, didn’t realize that. I’ve repeated the tests without AIC and the alarms works OK.
Have you tried to test the alarm with both TCC as Active?
Do you have another 15454s where we can verify the remote alarm notification?