Repeated M3900 Series phones getting damage on Option 61C

[Gigaic]

We have an option 61C and have over a year had about 60 phones damaged. The 1st which happened a year ago had 44 phones (M3901s, M3902s, M3903s and M3904s) damaged. We inspected the cards and saw that the circuits had black sooth on them suggesting some kind of sparks. The cards (all ports) still worked and so all we had to do is put new phones on and we were back.

It happened again about a month ago and 15 phones got damaged. They were replaced and just a couple of days ago, 9 out of the replaced 16 phones got damaged again. One of them (for a key manager) was immediately replaced and lasted for only an hour.

Are these phones repairable?

Any suggestions on what could be knocking off these phones? We are really in dire straits.

Thanks in advance.
George

 

[pbxn]

SOunds like you have an overnight date in the future to replace the back plane of that cabinet. During the times of the damage, has your area had storms? If so, I would suggest besides replacing the back plane, to have a proper (either Nortel certified tech, or licensed electrician) perform a power and ground inspection. Sounds like you had some sort of surge, whether it was from bad commercial power, and or improper site grounding.

 

[Johnthephoneguy]

i had an Option 11 kill about 40 phones before we found out it had a bad ground. Definately worth looking at!!

JohnThePhoneGuy

"If I can't fix it, it's not broke!

 

[johnpoole]

backplane power supply a REALLY bad ground.. cards with black sooth need to be replaced.. if it was a larger switch i would take some volt readings.. the opt is not built to allow that... if i had to relace one thing it would be the ps.. if that is drifting, getting hot and spiking talk battery.. almost like having lightning in a box

john poole
bellsouth business
columbia,sc