Proper grounding?

[standon]

With all the electrical storms we've been experiencing (not to mention equipment losses) I purchased a bunch of surge stuff. My problem is that the earth wire is about 30ft away from most of my equipment. I'm not totally sure I understand the nature of surges, but it seems to effect longer wires? My question is whether I should run 30ft of grounding cable to the main earth ground, connect it to the ground in an outlet, or something completely different? Any help would be appreciated, I may not even be using the correct terminology here.

 

[Del91574]

Grounding conductor should be as short as practical,bonded to the same EG as the building, and as heavy as an AWG as practical, minimum of 14 should be considered. The unprotected side of the circuit should be shorter than the protected side (if you are protecting cabling and not just equipment).

 

[video321]

That receptacle is already grounded. What you need to understand is the only effective surge protection is a very low impedance earth ground and a meter or panel mounted protector. Everything else is secondary.

 

[standon]

Grounding conductor should be as short as practical,bonded to the same EG as the building, and as heavy as an AWG as practical, minimum of 14 should be considered. The unprotected side of the circuit should be shorter than the protected side (if you are protecting cabling and not just equipment).

So if I used something like 8AWG, for 30', would that work? Or is 30' too far?

That receptacle is already grounded. What you need to understand is the only effective surge protection is a very low impedance earth ground and a meter or panel mounted protector. Everything else is secondary.

I purchased a Leviton TVSS, just waiting for an electrician to install it for me. I'm looking to ground things like my pool controller, which seems to be quite sensitive and expensive to repair (already damaged 3 times, the last time irrepairable and took out my Digi DB45 to USB device too). I bought a B&B high energy surge protector, but it states that it should be grounded to an earth ground. I'm really not sure how to do that considering the distance.

 

[Del91574]

As far as grounding the surge, you need to consider the fault current and consult article 250 of the NEC for the real answers, however it should be connected to the same EG rod or ground ring that the building is connected to, not a separate one, otherwise that creates the potential for voltage due to dissimilar grounds. Isolation of system interfaces is also another way to help mitigate surges.

 

[KeepItSimpleStupid]

I know I'm a little late for this thread, but I saw the word "pool" and also 30' away. Does 30' mean a detached structure?

A pool is a very strange entity to Earth properly.

To make the explanation extremely simple, there is usually one reference for the house and that is where neutral and the ground conductor are bonded together. Grounds are supposed to provide a reference and carry fault currents and there should not be any loops.

Let's say you have circuit A that consisted of a bunch of outlets and devices in parallel over a long distance. Now you also have n circuits wired the same way. Now suppose circuit A gets a direct lightning strike. Now all of the points along A'ss path will have a difference in the ground potential, so those circuits are at risk of getting fried.

The other n circuits never see the lightning strike. Not much can help here.

So, in an ideal world, each circuit being connected directly to the breaker panel would be a good, but inpractical thing.

The one thing that would help in this sort of situaltion is a whole house surge protector. Theese are installed at the main panel and have a low impeadance path to discharge into. This helps when the overhead line takes a hit or wires cross or a tree gets in the way.

Prevention is a good thing too. That might be a lightning rod system for the house or in the trees.

Pools are a very tough thing to deal with and there is a nice secion in the NEC about them. As it turns out, in a lightning event, the Erth is NOT equpotential. So, data lines in a datacenter that travel 200' within a building can have a difference in the reference potential. That happened where i used to work, so they changed those lines to fiber to just go across the room.

Equipotential for pools is a much different thing. A grid can be burried in the nearby ground and in the cement around the pool to make it a low Z system. It's typically detached, so it can and should have it's own ground rod system.

Yes, the general layout has to be looked at carefully to minimize problems. Cat5 run from the house to the pool area could have issues.