sundance-communications.com/forum Forums TDM Business Telephone Systems NEC Telephones & Systems phone wiring?

I deal mainly with Nortel but will work on anything if I feel I can give my customer good value for his buck. I moved an extension and added a jack for a customer that has an NEC system. The phones were 2 wire digital sets. I had the damnedest time getting the phone to come up on the new jack. I went back to the old location and examined the jack and found that the phone was working on the two outer pins, or the yellow/black wires. Once I wired the new jack up the same way, it came up fine.

Is this a common wiring practice for NEC systems, or is this some sort of hybrid system where the 2 wire phones or the 4 wire phone are both compatable?

What system?

Must be a Pro-1 (electra professional). Only one I can remember being on yellow and black pair. What type of phones? etw-16dc?

The ETW series phones were the ones that needed to be hooked up on the 2nd pair.

It doesn't matter what NEC system it hooks to, the E-Pro,Elite,IPK, Neax 2000, or 2400.


DJ

Thanks for the answers. They were ETWs.
So it was just a weird wiring for a particular series.

Thanks, Jim

I had same experiance, moved an extension, couldn't bring it to life till I wired the second pair and I'm talkin bout the single pair connected to 3/6 not center pair. Center pair was a non factor. I thought it was a programming option on the system an installer would use to protect his territory.

NEC digital VM integrations (AD-16, AD-40, AD-64, AD-120) also work on the outside pair. FYI.