One of my customer has 12 regular co lines,now they changed their service provider keeping the same no. of lines.This seemed prety easy but when i connected the new lines to the sx-200 El system, all trunks constantly rings bac on the console & if i try to access any trunk via att. access it shows locked. But still they are recieving incoming calls. The trunks are programmed on ls/gs trunk cards & the system uses LW 17.

Check the polarity of all trunks.

i did that but of no use,can this be something from the telco side.

check the ground start jumpers on your ls/gs trunk cards. you'll have to pull the card and find the little black jumper. I bet you now have loop start. Try out just one and see.

The other thing you might do is make sure that you have "ringing expected" set to yes in the CDN in form 13. there may be enough noise generated on the trunks to make the switch think they are ringing in when they are not. Setting up the above option will tell it to look for the correct ring timing.

the issue has been resolved. It was something to be done on the telco side, they said something related to nos. pouring in from the old service provider but as soon as they did it started working smoothly. Thanks for all ur help.

Thanks for letting us know

Hmmm, sounds like the 'porting' from 1 LEC to another didn't go too smoothly. I think that's what they meant when they said 'something related to nos. pouring in from the old service provider'. Porting, pouring, it's all the same, right? John C. (Not Garand)