sundance-communications.com/forum Forums TDM Business Telephone Systems Mitel Telephones & Systems Mitel SX-50 and Lightening

I have a Mitel SX-50 with aerial cable between buildings, lightening protection on both ends. The console is located in a different building than the switch. This switch is constantly getting hit and when it does it knocks the console part of the controller board out. I have tried everything. I was talking to a tech last week and he said he thought that the console and the switch were suppose to be in the same building and that it was recommened not to seperate the two with aerial cable. Any suggestions would be greatly appreciated.

Are you sure the protection is grounded properly on both ends,including bonding cable,Have you tried using the cat5 protectors on both sides of console cable ,I know it doesn't specify cat5 but the protectors might help if it is on a seperate cable.

I have gas tube as the primary and cat 5 as the secondary.All the grounds in the switchroom are connected to a cold water pipe. At the building where the console is located I have gas tube then cat 5 protection. It is grounded by a earth ground. Thanks for any suggestions

Aside from moving the console, I would consider buried, grounded, cable. Just a thought.

I know that this topic is a little old, but I will relate my experiences on the outside chance that it may help someone in the future.

Mitel recommends that the console not be located over 200 meters from the control card. If you exceed this limitation, you will cause the system to try to provide too much current to operate the console, shortening the life of the control circuitry (like the serial port limitations).

Also, your grounds are not the same in the 2 buildings. Ground potential differences between the two buildings can actually cause a current to flow along the shield of your cable between buildings. In these situations, I have found that bonding the messenger to both protectors and removing the ground with the highest resistance has eliminated most all of my "remote building" troubles. In cases where I have no messenger and have no way to bond the two buildings together, I have pulled the ground in one building and allowed my cable shield to put both protectors at the same potential. I don't like doing it (it makes me nervous), but it hasn't failed me as of yet.

Good luck.

Hi

anyway to bury the cable

if you cant move the console , could you move the switch to the building the console is in and feed stations back ?

install sneak fuses on cosole pairs
leave extra so customer can replace.100ma works fine max 350 ma.

good luck