AquaLogic lightning problem

[PoolDoc]

As a computer engineer, you already know that lightning and electronics aren't the best mix.

There a many possible problems that could cause this, but one possibility is an ungrounded pool bonding network. I assume you know what a Faraday cage is? Pools are required to have a bonding network that, if done properly, turns the pool, all rebar and gear, and the equipment, into a Faraday cage. However it is not required to tie the bond field to the grounding (or the electrical earth, if you know British English better). This has the potential to create voltage potentials between the pool bonding, equipment and water, and the grounding. Naturally, this potential will try to equalize via equipment (like the pump and the SWCG power supply) that are BOTH bonded AND grounded.

You may want to attempt to rectify this issue on your own, especially since relatively few electricians understand pool bonding, or the risk of voltage potentials between the bond and the ground. You can do all these things -- they may not help, but they should not hurt.

1. Make sure there is a WIRED ground AND a separate common between your pool power panel and the house panel. If not, have an electrician correct this.

2. Install a ground rod at the pool panel. You'll need these items, but you don't have to get them from HomeDepot:

http://www.homedepot.com/h_d1/N-5yc1...ProductDisplay
http://www.homedepot.com/h_d1/N-5yc1...ProductDisplay
http://www.homedepot.com/h_d1/N-5yc1...ProductDisplay

You'll have to see if you can get them to sell you cut pieces of the ground wire.

3. Make sure that you have WIRE grounds going to each piece of equipment, including the pump and the SWCG power supply. If your equipment has conduit grounds, you'll need to have an electrician pull wire grounds.

4. Run extra #10 or #8 bare wire FROM the ground rod nut, to the bond wire connections on the SWCG power supply and the pump motor. Ideally terminate the ground wire in the same connection point that the bond wire now occupies alone.

You may find you do not have anything like the bond wires and ground wires I'm describing. In that case, take a bunch of in-focus large photos of what you DO have, and let me take a look. (You may need some wiring repairs or updates.)

[STEPHAN]

Thanks for your help!

So, I checked the wiring.

The pool pump, the gas heater, the pool light transformer case and the control unit (Aqua Rite) all have their own grounding through a ground wire that goes from the metal case. Unfortunately I can only see the ground wires go into gray pipes. Pavers were put in later on. But everything was installed by a professional pool company and inspected.

The house has a surge protector installed by a professional electrician. I had an additional one installed on the pool control. All electrical wiring goes from the main control to the other devices like pool pump, heater etc. Everything uses the green “ground” wire in the electrical cable.

[PoolDoc]

I think you're misunderstanding -- grounding and bonding are similar, but separate. They are installed separately, and mandated under different parts of the electrical code. It's possible, has not always been required to join them. They are INTRINSICALLY connected, via equipment casings, at locations like pump motors that are required to be BOTH bonded AND grounded.

Here are some links you may want to check out:

http://www.poolforum.com/pf2/showthread.php?15099
http://www.poolforum.com/pf2/showthread.php?5210

http://forums.mikeholt.com/showthread.php?t=95495
http://forums.mikeholt.com/showthread.php?t=104422
http://www.erico.com/public/library/fep/LT1242.pdf

[STEPHAN]

I might be wrong, but I think that I did get it.

That’s why I wrote 2 separate paragraphs. I might have explained it wrong.

One on the ground wires going from the metal cases directly into the ground (not insulated) and one on the green insulated wires that are connecting all devices.

[STEPHAN]

So, I spend a lot of time reading all the links you suggested.

I now understand the difference in terminology. BONDING and GROUNDING.

If I got it correct, my lightening problems might be mainly a GROUNDING issue.

Any way I can check if everything is correctly grounded?

(I once had a customer who had everything "grounded" by a wire to and old metal pipe - but it was cut and not in use)

[STEPHAN]

@westom

The manufacturer took the board and replaced it. I was not able to keep it. I carefully inspected the board and it had absolutely no visible damage on both sides. There was a 3 amp fuse for the low voltage part that was blown. A 20 amp fuse for the high voltage part was okay. The technician disconnected all devices from the board and we replaced the fuse. I blew right away. So the error was on the board itself.