My IT department requires the use of a Cisco gateway (VG series) for 3 new elevators we are installing. We recently installed a new Kone elevator, and the VG will not function with this car phone system (AT&T analog lines were installed).

Any suggestions for our new installs? We have a new Kone, Fraco and Thyssen Krupp elevator on their way.

AT&T lines are a very expensive option for us, and not the preferred solution.

Your code jurisdiction will have some say as to what type of phone line can be used. You cant go wrong with an old analog line.

We have approval from the City to use a VOIP gateway, but for some reason we can't get reliable connections.

The Cisco VG has an On Hook voltage of 44VDC. Could this be the problem?

That should be fine. It's usually the off hook voltage that causes problems on these types of lines. The Thyssen cars should have Rath Phones, I don't think you will have a problem. Just make sure the line check feature gets turned off if it's a ring down.