Posted By: teldata1 Lightning Protection - 05/22/19 01:53 PM
I have a customer with an NEC SV9100 (School) That get hit with Lightning 1 to 2 times a year which blows out (2) of the 16 port digital station cards that are connected to another building
The phone system was installed in 2015 (Spring)

They didn't start having problems until summer of 2017 (They got hit once knocked out (2) Station cards going to another building they also had some other computer devises get damaged

Then again in summer of 2018 (2) Times

Then yesterday in 2019

Keeps blowing out the same 2 cards (which causes the whole system to be flaky until you pull the cards out

There is Lightning protection on this 100 Pair cable which is grounded my question is how can I tell what kind of lightning protection is installed I am thinking its not for digital phones

I am assuming that its for analog its been installed for a while

it just says Lucent Technologies on the cover

looking for some suggestions



Posted By: oobie Re: Lightning Protection - 05/22/19 02:56 PM
I would put some extra lightning protection like ITW-linx UPB-75 or 35 on them before the phone system. Give ITW linx a call they can help you out! I've been using them as secondary protection for a while now.
Posted By: Silversam Re: Lightning Protection - 05/24/19 07:41 PM
Carbon Protection is the cheapest and S H O U L D work on Analog Phones. For Digital sets or PBX cards you should use Gas protectors or one of the newer types (Thyristor, maybe? - I don't remember, having never worked on them).

Posted By: hbiss Re: Lightning Protection - 05/25/19 03:39 AM
5 pin gas tube or solid state protectors of the proper voltage, I believe 50 volts but you will have to check your system.

Also, I know you said the present protectors are grounded. That could mean anything but without actually seeing how it was done and what you have available I can't comment.

Posted By: Noobed2336 Re: Lightning Protection - 06/02/19 04:48 PM
For protecting 100 pair cable you should be using a 6g solid copper or equivalent conductor going to a ground rod that's also bonded to your building ground. You should be able to test < 25 ohms to earth with a megger at the connection. If it's not that good, then your protectors might not function.
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