sundance-communications.com/forum Forums TDM Business Telephone Systems NEC Telephones & Systems nec elite 48 questions urgent help

i have an elite 48 system with 8 onboard stations and one 4coi card installed. I have an amphenol connected to the 1,3,4 slot. I have dtu-16d 16 button digital telephones but cannot get them to power up. Now i was told that this system uses the outside pair on the rj11 jack but how can this be when the digital telephones only have a single pair wiring. i am assumming the 1st 8 pairs on the amphenol are the digital stations and the next 4 pairs will be for co lines.

1- does anybody know if these telephones are compatible
2- are the amphenol connections described above correct. If not how should the stations and co lines be connected to the amphenol.
3- All switch setting are in the off position or should they be any other way.

i would greatly appreciate any help provided i presently have an irate customer who is not to happy. if i could only get the telephones working it would be a great start.

Please provide the model of your telephone handsets. The ETW's should have 4 conductors, which uses the outside pairs for signal. DTP/DTU's will use the regular inside pairs for signal. It's helpful to look at the actual jack itself, and not the plug on the cable, since there's 2 and 4 conductor cables, and the end-users don't really care to know the difference.

Yes, your pinout seems correct. But before that, when you turn the system on what lights come on, and are they steady or blinking? Also, what slot is your COI(4) card in?

I AM USING DTU-16D SETS AND I HAVE TRIED INSIDE PAIR OUTSIDE PAIR WHICH I KNOW TO BE INCORRECT FOR THIS STYLE OF TELEPHONE. AS FOR LIGHTS I HAVE SOLID LIGHTS ON THE BACKPLANE FOR THE CPU INDICATORS AND ONE LOWER SOLID LIGHT FOR THE ESI, TOP LIGHT NOT ILUMINATING. I HAVE A COI-4 CARD IN SLOT 3 AND THAT IS IT.

actually new2nec is right. it uses the inside pair (wt/bl or red/green). ONLY the etw style phones use the outer pair.

your pinouts are correct for the 1st 8 pairs (digital stations), then you'll get the co lines on the next 4 pairs. the next 4 pairs are nothing. the next slot will then go on the next 8 pairs (or 4 depending on the card).


now to your other problem(s)

no blinking lights on any cards especially the cpu means that there is something wrong.

try removing any other cards from the system including the coi card then power up. you should have the cpu blinking.

the switches i couldn't find in the manual. pretty sure sw1-1 & sw1-2 should be off. can't remember off hand about the others.

you could try removing the memory battery, turn the system off, wait, then turn system on, plug in memory battery to see if it clears any data corruption. NOTE this will clear any/all memory!