sundance-communications.com/forum Forums Other TDM Phone Systems 1A2 and Comkey Telephones & Systems touch-a-matic

want to connect a touch-a-matic to 551b currently in my house need wiring transformer voltage etc.

Tim, you have come to the right place, but we need more information in order to help you. If you just need the transformer to power the Touch-a-Matic, you can get this power directly from the 551B. Is this a 6-button TAM or an adjunct? Give us more descriptive information as to what you need and we will hook you up.

20 number touch-a-matic with 6 line buttons on the top of the phone I have 3-2564,1-2851 and 2 comdial VX41 phone's connected at present.

It takes a 95B1 power supply which is 18 volts AC. You can also use the violet-blue pair in the station cable connected to PSB terminals 30 and 31 to send 18 volts to the station from the KSU power supply if you prefer.

Whoa! Ed, pardon me for the correction, but the 95B1 (the correct transformer for the Touch-a-Matic series) does NOT put out 18V! It's a 12-13VAC transformer.

You're probably thinking of the 85B1, which powers the 4A speakerphone systems and is indeed 18VAC.

Putting 18V to a TAM is a great way to let the magic smoke out...

Keep the peace(es).

We may be too late! Actually, I have a customer nearby still using one of these Touch-a-Matics that is wired to the 18 volt output of the KSU power supply. It's been like that since 1987. I guess it's pretty tolerant, but maybe I should go over there and change it.

Thanks for keeping an eye out though.

I only remember the TAM 16, TAM 32 (came as a oneline, 66 Button or an adjunct) the TAM 12 and the TAM S (adjunct 12 for a single line)

Not sure about a 20? Got pics?

Here is what I assume we are talking about:

Yes that is the animal were does the 12 wolts connect what pair?? Tim..........

According to factory wiring diagrams, the 12 volts AC should come into the set on the violet/blue pair of the line cord. This pair should terminate on PSB terminals 30 and 31 unless a previous installer changed this within the set. Bear in mind that this was common practice during the time that these sets were being sold and installed in an effort to utilize existing cabling.

You should check to make sure before you send power in on this pair just in case. It may be a low voltage, but if there's a short, there's still the risk of overheating and a potential fire hazard. You also run the risk of burning out a power supply.

If you would feel more comfortable, send 12 volts AC via a separate cord to terminals 30 and 31 and remove the violet/blue pair from them. Simply tape and store the ends of them individually. Unless you are absolutely certain that no bridging adapters exist, you won't know if the violet/blue pair is being used for something else at another station.