atcomsystems.ca/forum Forums Other TDM Phone Systems 1A2 and Comkey Telephones & Systems Weird issue on WECO 551B KSU

Hi Guys,

I am having a weird issue on my WECO 551B KSU. Everything was working prefect after punched down the station cable and the incoming Phone CO lines. Did some tests and everything was working..

After I moved the KSU to the side to clean up the mess the weird issue started. The buzzer in the phone turned on and stayed on continuously and will not turn back off. The only time its off is when a incoming line comes in and the interrupter starts up after the call is disconnected the buzzer will turn on continuously again.

I swapped phones and line KTUs and the same issue.

I am wondering if I have a open circuit that I am not seeing or not seeing what could cause this.


Any thoughts on this?





Thanks Brian

Is the buzzer for Intercom or CO signaling?

The only time a device will ring continuously is when it has battery and ground applied to both sides.

Do you have a short on the block between power (RB or 18/10V) and the buzzer?

You could possibly have a defective interruptor. I'll have to pull the prints, but you'll need to check where power comes into the interruptor and then where it's supposed to come out. Is power coming out constantly on leads where it shouldn't

It'll take me a while to find the paperwork. Sorry.


Sam

Here is the wiring diagram...

Click me, Click me!

Hi Guys,

Thanks for the help. The buzzer is for CO signaling and its happening on all of the 2 lines so far. Very strange that everything was working right until I bumped it. So it could be something came lose....

Power is only coming out constantly the B1 and R1 leads.


I will take a closer look tonight. I do have a extra interrupter and see if that will fix the issue.


Thanks Brian

Everything was working fine until the telephone man was here!

              

MYSTERY SOLVED!!!!!!

It turned out it that it was the two 400H cards, once I tried a 400E card it worked..... If I remember right, few people said that the 400H cards are not so reliable. I also had a issue with the 400D card not ringing so I am thinking that card might be bad since I only have one of those.

Thank you for all your help.

I was right!

Glad you found the problem!


Sam

400D cards won't ring on most modern lines unless modified. There may be nothing "wrong" with it, other than it being made for grounded ringing which doesn't exist anymore.

There's a mod to make them work. PM me for details.

Thanks right, I just remember that you did let me know about the 400d cards a while back Chris.


Professor Shadow, with my luck something always goes wrong.....