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antipode12
Jul 17, 2009, 07:53 PM
Hi -- Second summer in this house.

I just replaced my above ground pool pump. I noticed it has a screw to attach a ground wire to, as per the instruction manual. The last pump also had it, but had no ground wire either.
[EDIT: I'm not talking about the green screw in the wiring compartment. I'm talking about a copper compression screw OUTSIDE the motor housing.]

Should I attach a ground wire to it, and if so, connect it to... what?

Here's the layout:
I THINK the pool receptacle is grounded and GFCI-ed. (20 amp dedicated receptacle -- Twistlok -- the breaker has a "test" button on it.)

Next to the pool pump is an 8 inch copper rod sticking out of the dirt. It has a jumper wire that goes into the dirt, and nearby resurfaces next to the pool's wall. From there, the wire goes off -- toward the house -- into the dirt again.

To be clear: there is no (visible) copper ground wire connected to the receptacle or to the pump.

What to do? Thanks.

tkrussell
Jul 18, 2009, 03:51 AM
Check with your local electrical inspector to see how he wants pools grounded.

National Electric Code does not require, nor does allow, a ground rod at a pool to ground it.

The main link to grounding a pool is the exposed lug on a pump motor. All metal within five feet of the water's edge around a pool, to include fencing, handrails, diving boards, ladders, metal supporting walls, reinforcing rods in concrete, is bonded with # 8 copper solid wire and connects to this lug you see, amazing, unused, on the pump motor.

The pool is then grounded by the equipment grounding conductor of the branch circuit that feeds the pump.

Any inspector that requires or allows a ground rod anywhere but at the main service does not understand Code or grounding.

After speaking with the inspector, hire a qualified electrician to come in and make the necessary corrections to comply with local code.

antipode12
Jul 19, 2009, 12:48 PM
Thanks for the info.

I'd like to correct it myself if it's feasible.

You're saying that the lug on the motor should be BONDED to the rest of the pool's metal?

Should I assume that the #8 wire that already exists attached to my pool is the bonding wire that I should connect to? Is there any way to confirm it? (As I mentioned, the wire is clamped to the pool's wall, and then leads into the dirt.)

ballengerb1
Jul 19, 2009, 03:05 PM
Do not bond your motor to the pool metal. Do like TK recommended.

antipode12
Jul 19, 2009, 08:49 PM
OK - then let me ask two quick related questions:
1-- how do I test that a "twist lok" style outlet is grounded?

2 -- how do I test that the GFCI protection on the pool's circuit breaker works?

KISS
Jul 19, 2009, 09:05 PM
What I'm going to tell you to do is the following assuming it's a 120 V system:

Purchase a twist lock plug or "borrow" it from the pump. Get a 3 prong female extension cord end. Wire it to the twist lock.

Get one of these:

GFCI Receptacle Tester (http://www.gilchrist-electric.com/gfcireceptacletester.php)

Plug it into the gizmo you made.

It will tell you if it's grounded, but not how well it's grounded. The GFCI button will test the GFCI.

There should also be a GFCI test button on the breaker.

The GFCI could be tested with a resistor sized properly and the ground with an ohmmeter. Details purposely left out.

antipode12
Jul 19, 2009, 10:00 PM
Thanks for the GFCI info. Makes sense.

Regarding the bonding issue, I hope this doesn't coming across as confrontational, but I've been doing some reading. It seems like a pretty straight-forward thing: #8 wire connects all of the metal of the pool to the pool pump lug. It does not tie into the circuit branch.

So why is TK telling me NOT to connect the existing #8 wire (bolted to the pool walls) to the pool pump?

I understand the ground rod is a complication. I will investigate tomorrow, but I suspect someone BONDED the pool to a ground rod. To correct, I would remove the bonding from the rod.

Can anyone explain to me why this is incorrect?

(By the way, if I seem reluctant to just call the electrician, it's been a killer week: bee's nests inside the house, carpenter ants in the joists, a gas leak buried in the wall, a burned out pool pump, and a roasted catalytic converter. I'm trying to save the $125 for the electrician if possible.)

KISS
Jul 19, 2009, 11:07 PM
Thanks for the GFCI info. Makes sense.

Regarding the bonding issue, I hope this doesn't coming across as confrontational, but I've been doing some reading. It seems like a pretty straight-forward thing: #8 wire connects all of the metal of the pool to the pool pump lug. It does not tie into the circuit branch.

So why is TK telling me NOT to connect the existing #8 wire (bolted to the pool walls) to the pool pump?

I understand the ground rod is a complication. I will investigate tomorrow, but I suspect someone BONDED the pool to a ground rod. To correct, I would remove the bonding from the rod.

Can anyone explain to me why this is incorrect?

<snip>



He's not telling you not to connect to the pool pump grounding lug. He's telling you to connect that #8 that goes to the walls there instead of the ground rod.

Your pool needs a SINGLE reference and that is the panel in the house (there is a ground rod there or an alternative means that bonds the neutral to ground.

The pool pump should have a ground to your panel and this is your reference.

You CANNOT create a separate reference using a ground rod at the pool.

Since you said the wire is buried in the dirt, it actually may be going to the house ground/neutral bond which isn't a bad thing. Maybe better that what's suggested by code.

Rationale:

Your cable, phone and power are all connected to earth at a single point if done correctly. The telephone would connect the other end of it's surge protector to that single ground rod, cable would do the same and so would your service.

If you had a detached garage, you would be required to put in a ground rod. Is a pool considered detached? Don't know?

Now if your ground goes back to the single ground point and your pool gets hit by lightning, then because it goes back to a single ground point, the house ground, poll ground and any other ground doesn't see a rise in potential. In other words, the strike won't affect anything.

If you grounded the pool with a rod only, then the pool would be protected, but the grounds in your house, including the pump, would show a rise in potential relative to the pool.

Pools should have an insulated ground in PVC conduit back to the panel. That's the way it's supposed to be. An extra ground rod at the pool should make no difference at all. It is similar to ground rods being required for sub-panels in detached structures. In that case it's for lightning protection, not grounding.

What you don't want to do is create a different reference (ground) for the pool which is different than your service.

If your pool is wired with a ground rod AND a connection all the way back to the building's bonded ground, your installation may be superior, but not code.

If the pool's ground rod is the only ground for the pool, that MUST be corrected.

You can read the NEC online by following the sticky in the Electrical and Lighting section.

tkrussell
Jul 20, 2009, 02:38 AM
This is what I said:


All metal within five feet of the water's edge around a pool, to include fencing, handrails, diving boards, ladders, metal supporting walls, reinforcing rods in concrete, is bonded with # 8 copper solid wire and connects to this lug you see on the pump motor.

The pool is then grounded by the equipment grounding conductor of the branch circuit that feeds the pump.

Kiss explained further to clarify correctly.

If you go visit the local electrical inspector, they usually have a sketch or diagram showing all the items that need to be bonded to the lug on the pump motor, and how it gets connected to ground via the equipment ground conductor that serves the pump motor.

The sketch helps with showing all the items that need bonding, to help identify and not forget those items.

Sorry to hear about all your problems.

Hmmm, a burned out pool pump? What caused this?

Pool grounding and power wiring is nothing to fool with. $125.00 is cheap insurance to be sure the pool is wired and grounded properly. Most do not know how important the bare copper wire is.

tkrussell
Jul 20, 2009, 05:21 AM
Here is one that shows how this town wants pools wired and grounded:

http://www.invillapark.com/UserFiles/File/Community_Development/SwimmingPools,Hot-Tubs,Spas.pdf

Note, there is no ground rod.

I have found other cities that do require ground rods. If they would only UNDERSTAND the National Electric Code, but oh well, they are the AHJ (Authority Having Jurisdiction).

Read through this package, to see what is invloved with pool wiring.

antipode12
Jul 20, 2009, 10:56 AM
Thanks a ton, guys. I know I seem dense.

I dug up the bonding wire, and it connects all of the pool wall and then leads to an 8' buried rod. Nothing else connects to this rod. It seems that the builder bonded the pool to a grounding rod.

The pool pump has no bonding, and I checked its receptacle: it is grounded to the branch circuit.

Soooo, unless you tell me that I'll shoot my eye out, I'm going to remove the bonding wire from the ground rod, and attach it to the pool pump.

TK - pool pump burned out after 9 years of use and poor winterizing.

KISS
Jul 20, 2009, 11:05 AM
Sounds like a plan. Invoice: $125 to be shared equally:)

tkrussell
Jul 20, 2009, 11:37 AM
Thanks a ton, guys. I know I seem dense.

I dug up the bonding wire, and it connects all of the pool wall and then leads to an 8' buried rod. Nothing else connects to this rod. It seems that the builder bonded the pool to a grounding rod.

Pool grounding is widely misunderstood, even by some inspectors, but pool guys usually know since they see so many go up.


The pool pump has no bonding, and I checked its receptacle: it is grounded to the branch circuit.

There you go, the pump motor is grounded by the circuit's equipment grounding conductor, and the pump motor will be "bonded" to all the metal related to the pool. This connection of the #8 solid copper wire creates the equipotential grid surrounding the pool, keeping all metal at earth or zero potential. If something does energize any part, it will be low impedance ( AC resistance) and allow current to flow and rise quickly, and trip a circuit breaker.

Check these connections at the beginning of each season.


Soooo, unless you tell me that I'll shoot my eye out, I'm going to remove the bonding wire from the ground rod, and attach it to the pool pump.

I never heard it put that way. I love that movie.

Do exactly as you suggested, including checking each connection the #8 makes around the pool, be sure every ladder, diving board metal, fence, any metal within 5 feet of the pool, and at the service grounding. This may be your incoming metal water line, and/or ground rods driven near the service.

Interesting post recently reminds to suggest that any utility poles nearby, that have a bare copper wire running to ground, be sure those are connected to the rod nearby.

This is something I will look for when troubleshooting grounding problems, not just for pools. I never thought of suggesting to homeowners.


TK - pool pump burned out after 9 years of use and poor winterizing.

OK, that is reasonable. Just wanted to be sure it was not another symptom.




Sounds like a plan. Invoice: $125 to be shared equally:)

Kiss... 60/40?