sundance-communications.com/forum Forums Other TDM Phone Systems 1A2 and Comkey Telephones & Systems 551B KSU Ringing Issue

I have a 551B Ksu id like to hook up in my work shop; I have it wired and on line 1, I can put the phone on hold, interrupter starts and lights flash. On line 2 when I push hold, the lamp just shuts off and the call drops. I have swapped the cards; that doesnt appear to be the issue.

On incoming calls on either card, the interrupter does not start, lamps dont blink and phones dont ring.

551B ksu with internal power supply and separate ringing supply.

Any help is much appreciated, I am sure there is something easy I am overlooking.

The no-hold condition on line 2 sounds like the card is bad, but since you swapped them and the trouble remains, I would check the wiring of the second line. Before you check the station wiring, here's a quick test that you can use to simulate a hold condition: take two metallic tools, such as two screwdrivers, and do the following in this order: short the T&R terminals of the line at the KSU output block. Then, while that short is there, short the A & A1 terminals at the same block. The lamp should light at the phone. Now remove the short on the A & A1 terminals while keeping the short on the T & R. The lamp should change to wink, and the interrupter should begin to operate. This test eliminates any wiring issues outside the KSU, and tests the KTU by itself. If this test results in a good hold condition, then the trouble is in the wiring or the telephone set. is the set wired for 1A2 or is it possible it was once converted to 1A? Do you have another tel set you can use temporarily? Do you have more than one tel set on the system?

As far as the incoming ring not operating the interrupter, we need to know what brand and issue of line cards you are using. (Some cards will respond to metallic ringing (across T&R) and some will only respond to grounded ringing.) That will help us figure out the ringing problem. Until we know that, consider this: Have you grounded the KSU to an earth connection? The easiest way to test if this is the problem is to run a piece of cross-connection wire from the ground screws at the top of the 66 block in the KSU to the center screw of a convenient electrical outlet. Do this and ring into the lines again.

Arthur is, as always, on the $.

Also, do you have only 1 tel set? If you have more than one, does the (line 2 hold) problem exist on both sets?

WH8428, follow up and let us know.

Sam

Some of the later versions of WE 400 cards had a weird symptom: If you picked up a line and immediately tried to place the line on hold, the call would drop. The card needed a few seconds connected to the T & R before it would hold. I believe that the 400G or 400H cards did this. It was most unsettling for an installer back in those days, not knowing that the card operated that way by (poor) design.

That's odd, Arthur. I'm running my FIOS lines with 400H & G cards. I was using SanBar 4000F's but was having problems with ringing. I started cycling cards in and out and the later WECOs have worked fine.....

Sam

No dice on either line now, so whatever the problem is its intermittent. The interrupter isn't starting on incoming ring either. I will post a pic of the wiring shortly.

I do have multiple 1a2 phones and cards; all have the same results.

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As always you guys were on the money. I grounded the KSU properly and the interrupter starts on incoming ring and everything works properly.

Thanks for the help

Arthur, I believe it was the 400E that had the problem

Glad to hear that everything worked out.

Sam