atcomsystems.ca/forum Forums General General Telephone & Systems Information line Amperage

I have 4 POTS lines coming into a building. Measuring with my digital buttset I get 51V on all 4, 30ma on line 1, and 50ma on 2,3, and 4.

The measurements were made at the Demarc with inside wire disconnected.

Should all 4 amperage measurements be the same? Are the ma measuments within spec?

Before the breakout there is a Western Electric splice (?). The building was built in the 40's, and assume the cable was dropped in maybe during the 60's or 70's.

The reason I ask is because we keep losing Line1 on the CID Line Card of a CICS. This is the 3rd card that lost Line1 since August. I searched around the net and couldn't find anything on bad card runs failing lines.

Thanks!!!

If all lines are being delivered the same the ma's should be the same. I'm betting you have one line on copper and 3 via local carrier or visa versa. The only thing the Telco's go by is a minimum of 23ma so all lines are within limits. The ma shouldn't affect CID but line levels could. If anything was going to get the card I'd think it would be the high current levels not the low. You could put a loop current regulator on the 1st line and see what happens.

So I'm assuming just resetting the card doesn't clear it?

30 mA is a bit high, but 50 is way too high. In general, 24-27 is ideal for loop current. There are several factors that can contribute to this difference. In many cases, one line may be running over traditional copper all the way from the central office while the others may be running on a SLC or other form of pair gain equipment. Lines can take many different routes to reach the premises.

Please don't bother opening Verizon's splice. They would not be happy if you did that, not to mention the fact that you won't find anything in there. You will also not receive much cooperation from them regarding the inconsistencies. If there's dial tone and it rings, that is all they are concerned about.

Your best bet is going to get some loop current attenuators from Mike Sandman ( www.sandman.com ). They aren't cheap, but they will take care of this problem.


EDIT: I moved this here to Nortel . It was that or Telephone Service, but I wasn't sure if this was a known problem or not. Bill