Multiple phones on one FXS port

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1

I have a Zapmicro ZMA400P TNIC and I want to power multiple phones from one FSX port. I have no need for them to be separate extensions so that is not an issue but I am concerned with current draw and power issues.

First, can I drive multiple phones from one FSX port without frying the card and if so how many?

Second, will the voice and call quality (volume, noise, etc) suffer dramatically if more than 2 or three phones are powered by one FSX port? Would an amplifier circuit help this?

Thanks for your help

2

Two questions:

  1. How many of those phones that share one FXS port are to be off-hook at the same time? If they’re in use one at a time, there should be no problem at all. If all of them are off-hook at once, the audio level will probably be low.

  2. How many phones are to ring at the same time? Add up the ringer equivalence numbers of all of the phones and compare the sum with the maximum specified ringer load for the port. With today’s solid-state ringers, this is usually not an issue.

3

Thanks for your reply,
I have been trying to contact zapmicro (via chat, email, and phone) but have had no success. Trying to contact any of their distributors has been unsuccessful as well. That being said I don’t know what the max ringer load is yet. Does anyone know for this particular port? (zms100 fsx port on a zma400p11 card)

The system will only be used with two phones. Ringing and/or off the hook at one time. Three maybe. Its for demonstration purposes for our senior project.

Thanks for your help

4

Every FXS port I’ve ever seen can support two phones. I would be very surprised if yours can’t.