Grounding Equipment/Surges

We are installing some ETH-SP and they need to be grounded.

We have a Hannah enclosure on the exterior of an apartment building. Electrical is connected to panel, where the ground and neutral are shared. No dedicated ground busbar.

The Hannah enclosure has a metal mounting plate, with provisions for it to be grounded. Our thought is to connect this backing plate to the electrical ground, then connect the ETH to the plate.

Will this work?

For surge protection, is it OK to use a ground that is a shared neutral/ground? Or do we need to install a grounding rod?


This seems like a good plan to me. Making sure the neutral is, in fact, grounded may be prudent, but otherwise using this ground falls according to intended use.

In terms of outdoor surge protection, that's a fancy name for 'where a lightning strike goes', so keep in mind that sharing a neutral could toast a fair amount of internal building wiring if your enclosure is pinpointed as the attractor.

In many cases, a driven rod may be cheaper to install as insurance of sorts than rewiring a building and the switchgear. But that is awfully dramatic to think about...

For all, see our Grounding and Bonding for Video Surveillance tutorial for more.

Should the rod come off the enclosure plate or off the panel?

Electrical is connected to panel, where the ground and neutral are shared. No dedicated ground busbar.

If this is a subpanel, there is an NEC violation, ground and neutral can only be bonded at the main panel, and not in any subpanels.

You may also have issues if you are planning to install the ETH-SP inside the panel, as you'll be mixing high volt and low voltage inside the panel, where the low-voltage is not directly related to monitoring or controlling the high voltage loads.

If that is the main panel, then it should (better!) have a ground wire that is going directly to a ground rod.

You might be better off mounting the ethernet surge protector in an external box, and running a ground wire from that box to the Hannah panel.

The panel is a small main panel for house power. Neutral and ground together. There is no ground rod, and my electrician said on older buildings that is how it was done on older buildings.

Hannah enclosure is outside with switch, UPS, and surge protectors. Electric is brought to the Hannah enclosure. Surge protectors are grounded to the electric ground, which basically is the shared neutral ground. He said this would work but it would be better to install a ground rod near the enclosure and ground our surge protectors to that.

IMO I don't think its cost effective. This is all Ubiquiti equipment, maybe 700-800 worth of equipment at each box. Multiply this time several buildings, time 20 properties. I think replacing a couple cameras every year is more cost effective. Also, we are putting a surge on the radio line to protect the switch from any ESD that may come in but all the cameras are just as vunerable....

OK, I think I understand what you are working with. The enclosure you are talking about is not a an outdoor sub-panel, just an equipment box. Just for clarification, is it a "Hana" enclosure: hanawireless.com ?

For what you are talking about, I think you can/should ground the surge protector to the grounded metal plate in the enclosure and be done with it. Driving an extra ground rod probably wouldn't hurt, but may be more trouble than it's worth, depending on how rocky the soil is.