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APS · 28-08-2012, 16:30

We had a nearby lightning strike which took the VM SH offline (would not sync) and seems to have killed a router connected to the VM modem. The router power comes via way of a transient protected mains supply and a UPS, so I am pretty sure the surge may have come in via the VM cable. There is some evidence it may have caused some form of ground bounce.

The engineer came out and moved us onto a different tap in the local cabinet which seems to have fixed the connection problem for now - it seems the surge had damaged the kit in the cabinet rather than the SH itself.

I wish to avoid any further damage to our network hardware I asked the engineer about any lightning protection fitted on their kit. He did not know too much about it but said the isolater (a VQ301) fitted in our wall box should be adequate protection.

When I look at the VQ301 there is an earth connection on the outside shell of the isolator. The engineer say they are never earthed. Why is this? If there are any internal protectors they would need an earth connection to be truely effective as stated earlier in this thread.

Is there any harm in connecting it to earth?

28-08-2012, 16:30	#10
APS Inactive Join Date: Jan 2004 Posts: 216	Re: Surge protecting your network We had a nearby lightning strike which took the VM SH offline (would not sync) and seems to have killed a router connected to the VM modem. The router power comes via way of a transient protected mains supply and a UPS, so I am pretty sure the surge may have come in via the VM cable. There is some evidence it may have caused some form of ground bounce. The engineer came out and moved us onto a different tap in the local cabinet which seems to have fixed the connection problem for now - it seems the surge had damaged the kit in the cabinet rather than the SH itself. I wish to avoid any further damage to our network hardware I asked the engineer about any lightning protection fitted on their kit. He did not know too much about it but said the isolater (a VQ301) fitted in our wall box should be adequate protection. When I look at the VQ301 there is an earth connection on the outside shell of the isolator. The engineer say they are never earthed. Why is this? If there are any internal protectors they would need an earth connection to be truely effective as stated earlier in this thread. Is there any harm in connecting it to earth?