atcomsystems.ca/forum Forums General General Telephone & Systems Information Troubleshoot elevator phone

I am an electrical contractor who recently did electrical demo in a vacant 3 story building i just recently got a call from the facilities company that there elevator phones arent working anymore. Common sense would say that during the demo me or one of my workers cut the phone line to the phone. my question is after the wiring from the phone in the cab leaves the cab where does it go into the elevator machine room? and is that where the data contractor would make his connection to the actual line and from there where the actual phone line would get landed to receive the phone # for instance would it be in a local data closet or a specific module used separate from normal phone lines. I don't really deal with the communications aspect of electrical just mainly commercial electrical work so i am not familiar with the logistics of how the phone system works. Any advice that could put me in the right direction would be greatly appreciated

Most (but not all) elevators work like this:

Phone device connects to the cabin cable which ends in the elevator control. SOmetimes there is a dialer built in to the control but some have the dialer built into the phone and some have the dialer as a separate unit at the telco backboard. Some don;t even have a dialer. In the elevator control, a cable carrying dial tone can either can either terminate directly onto the circuit board via screw down terminals or a modular plug. The cable usually exits control box via a low voltage conduit, either in the conduit or sometimes strapped to the conduit.
From there it makes its way to the main telephone room, either directly or through a series of connections of outlying closets or blocks hidden in the ceiling or wall panel.
Finally at the DMARC (telephone room) the dial tone should be crossconnected to a RJ21X (usually a 66 block with an orange cover with phone numbers labled on it). The phone number (if your lucky) will be labled and be designated as elevator. Usually this line is a dedicated line that only is used for the elevator.
In some localities it may be permissable to have the elevator dial tone originate in a phone system, but that usually only happens in a 1 tenant facility.

thankyou billflippen so basically if something was cut it would be where it leaves the elevator machine room and heads to the main telephone room? I guess that would make the most sense considering we really didnt do any work in the cab or the elevator machine room i guess i will try to find the telephone room that is supplying the elevator phone and backtrack from there thankyou for breaking it down for me

Often the telephone line leaves the elevator shaft at a "mid-point box". This is (obviously) at the middle of the run. In a 15 story building it would be on the 8th floor.

However, I have often seen them on the top or bottom floor too. As to where it goes in the elevator machine room? You're going to have to get the elevator company down there and ask them.

Tracking it back from the telephone room is a good bet. Get yourself a toner and a wand. It'll help a lot.

Sam

Another point to check is in the Elevator Room on the electrical control circuit board, there is a screw terminal connection point usually labeled:


TELCO
__________
|TIP|RING|


This is also a good point to check.

Is there dial tone there?

• Yes</font><ul type="square">
• The problem is lies between there and the elevator cars.

[*]No

• <font size="2" face="Verdana, Arial">The problem is bewteen the equipment and where TELCO comes into the building. 99% of the time this is just one cable without splicing and tapping.

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I hope this help and doesn't hinder.

cab phone to travel cable (or separate cable) to machine room to line to demarc - it basically NEARLY ALWAYS is that simple

most of the time the cab has an auto dialer connected to a regular 1FB line (like in your home, though not always)

I just put a tone on the line in the cab at the auto dialer, check the machine room for tone, and continue tracing tone to the phone company demarc

I've never encountered anything "tricky" (fire marshals and jurisdictions frown on "tricky")

I've never had a break in the travel cable to the cab - machine room cabinet to demarc, 100% or the line is dead or "accidentally" ordered turned off

In our tiny hospitality 2 and 3 story structures, you open up the cabinet in the mechanical room for the elevator and you'll see a modular jack and a jumper. We usually get to run our cable in the wire tray that feeds that cabinet, but sometimes we have to use conduit or flexible plastic tubing. Anyway, you should be able to trace out where the dial tone is supposed to enter the elevator phone.

Now you just have to get dial tone to that cable.

Many of us on this board have dealt with elevator phones in some fashion or another. Working around rotating machinery or opening a control box with myriad of relays and power sources can be a daunting task. Above all else, Think Safety and Practice your Trade Safely!