atcomsystems.ca/forum Forums Telephony Discussion Phone & VoIP Systems Vodavi Telephones & Systems ac voltage on line

custoner called and line 1 wasnt ringing. its a stse. i moved it to line six and programed it and it was ringing. this morning they called and said it wasnt ringing again. i was going to replace the ksu but when i got there it had 130 volts on the co line. when ringing it jumped to 160 vac. when off hook it went to 25 vac. it was high on line one and two but not 3 and 4. a few minutes later it would be ok on 1 & 2 but high on 3 & 4. this happened over and over until the phone company tech popped in. he used his tester and said there was no ac voltage on the line. i put my meter on it right after him and registered ac voltage. i put my volt meter in an ac outlet and it registers correct. anyone have an idea whats going on here. thanks dave

I found this site extremely helpful with POTS lines. He has a test page that you fill in and it helps determine where the problem might be.

https://www.sandman.com/loop.html

I don't work for the company nor do I know him at all. Found the site while trying to troubleshoot problems. It helped me out.

-Stephen

Take the Caller ID card out of the STS cabinet and see if clears anything.

i will take a look, thanks. as far as the cid card i dont think it is that. i was testing line one with it not connected to the system. the other ones were connected to the system when i tested them but i did try it with the ksu turned off. it really does appear to be coming from the telco.

130 volts is used by telcos on analog loops that are extremely far out from the CO to compensate for voltage drop. This is most common in OPX circuits. In this area, the CO technicians refer to the loop extenders used as "Lorrain units". You really need to get this resolved because this voltage will most certainly continue to blow ports on this (or any) KSU.