atcomsystems.ca/forum Forums Wiring - Telecom Carriers - Trunks & Services Telecom Service & Providers crossed lines?

Hey guys. I was dispatched on a service call to a bank recenty that the customer states that the police department is receiving calls from the bank. The customer gives me the number that the police say that is calling them. It's the cash advance line for credit cards. Sometimes the cash advance line is shared with the alarm panel. The customer suspected this to be the case so he asked me to check and if possible move the cash advance line to a unused line if possible, than we could look into bad alarm dialer etc. Well the alarm panel and cash advance lines are not together. They are indeed on seperate dedicated pots lines. I also noticed there is a number coming into the branch not being used at all that the branch doesn't own. When I dial this number with my buttset a fax machine answers the line. There was also bad static on the lines. So I assumed that possibly there is some crossed lines outside the bank and advised for them to have AT&T come out and take a look outside. I never heard back from the customer. Was my assumption possibly the correct one? Does this happen on occasion to any of you guys?

Are these 911 calls?

-Hal

I'm assuming they are. The police have arrived on several occasions.

Kevin -

Telcos used to (still do?) use something called a "Bridge tap" or "bridged count".

Imagine you need 5-8 lines at each of 3 buildings. Instead of pulling a 25 pair count to building A and a separate 25 pair count to building B and a separate 25 pair count to Building C they pull the SAME 25 pairs to each of the buildings (either a feed from a common, central splice or a loop).

In building A they use pairs 1-5, in building B they use pairs 8-17 and in Building C they are using 20 - 25. This is substantially cheaper and what the heck - we're the phone company, we don't have to care. But now building C needs a new line so they pick pair 6 and later building A needs another circuit so they pick pair 19 and.....

You get the picture. It gets ugly real quickly. In this scenario it's very easy for either someone to pick the wrong line to hook up to or a ring side short could show up as a dialed call with the wrong caller ID

Sam

I suppose that could be it. Thanks Silversam. This call was about 2 weeks ago and it had me wondering ever since.