Jacuzzi pump ground lug

[Marc]

Can someone point me in the general direction of cites relating to the grounding of jacuzzi pump motors? Today's jacuzzi had a ground lug so I'm assuming it isn't a double insulated model. The fresh water supply is PEX but I suspect PEX doesn't make it ok to leave that ground lug hanging.

Thanks.

Marc

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[Bill Kibbel]

I don't have a reference in front of me, but that external terminal is for bonding, not grounding. The motor should be grounded with the cable's ground conductor.

Hydromassage pump motors are to be bonded to associated metal parts and metal piping systems. If there's no metal for supply and drain or other tub parts, there's nothing to bond.

[Marc]

Makes sense. The faucets are metal. I'll see if I can return to look again.

Thanks.

Marc

[Scottpat]

Makes sense. The faucets are metal. I'll see if I can return to look again.

Thanks.

Marc

The faucets are a moot point if you have PEX and PVC!

No need for bonding.......

[kurt]

Throw in the other fact that all the piping for the spa is plastic, and water by itself isn't conductive, and the need for bonding is arguably silly.

Isn't it?

[mjr6550]

The NEC used to say that bonding was not required on residential installations, unless required by the manufacturer. I don't know if that is still the case. I would go with what the manufacturer requires.

My pool pump is bonded and all of the connecting piping is plastic, which is typical.

[John Kogel]

How do you connect a bonding strap to a faucet? You don't. If there is no copper pipe over 10 feet in length, a plumbing bond is not required. Don't quote me, but that is a rule of thumb if you can't find a better one.

As Bill said, the electrical is grounded/bonded by the grounding conductor.

[mlparham]

Throw in the other fact that all the piping for the spa is plastic, and water by itself isn't conductive, and the need for bonding is arguably silly.

Isn't it?

Very silly and useless. Certainly a "Top 10" bad finding by home inspectors to ask for bonding in this situation.

[Eric B]

I recently delved into this and was told that the pumps can be used in a variety of circumstances and not all of them will require the bonding lug connection. For a tub in the home with metal water pipes then all that is needed is the three prong plug connected to a grounded receptacle. If the pumps is on an exterior tub then the lug should be utilized. I don't know if this is the ultimate answer but it's what I'm going with at present. I also don't know the answer to plastic water pipes being present - we don't have much of that here.

[Marc]

I recently delved into this and was told that the pumps can be used in a variety of circumstances and not all of them will require the bonding lug connection. For a tub in the home with metal water pipes then all that is needed is the three prong plug connected to a grounded receptacle. If the pumps is on an exterior tub then the lug should be utilized. I don't know if this is the ultimate answer but it's what I'm going with at present. I also don't know the answer to plastic water pipes being present - we don't have much of that here.

That's a nice tidbit of info there. It explains Bill K's point and also a lot of situations where the lug is there and the HI is...ahem... scratching his head, trying to 'connect the dots'.[:-paperba

Marc

[Jack Davenport]

I will assume you are talking about a Hydromassage Bathtub as Jacuzzi is a brand name.

The bonding of such is covered in Part VII of section 680 in the NEC.

From the 2011:

680.74 Bonding. All metal piping systems and all grounded metal parts in contact with the circulating water shall be bonded together using a solid copper bonding jumper, insulated, covered, or bare, not smaller than 8 AWG. The bonding jumper shall be connected to the terminal on the circulating pump motor that is intended for this purpose. The bonding

jumper shall not be required to be connected to a double insulated circulating pump motor. The 8 AWG or larger solid copper bonding jumper shall be required for equipotential bonding in the area of the hydromassage bathtub and shall not be required to be extended or attached to any remote panelboard, service equipment, or any electrode. The 8 AWG or larger solid copper bonding jumper shall be long enough to

terminate on a replacement non-double-insulated pump motor and shall be terminated to the equipment grounding conductor of the branch circuit of the motor when a double-insulated circulating pump motor is used.

[kurt]

I recently delved into this and was told that the pumps can be used in a variety of circumstances and not all of them will require the bonding lug connection. For a tub in the home with metal water pipes then all that is needed is the three prong plug connected to a grounded receptacle. If the pumps is on an exterior tub then the lug should be utilized. I don't know if this is the ultimate answer but it's what I'm going with at present. I also don't know the answer to plastic water pipes being present - we don't have much of that here.

That's right as far as I'm concerned.

[Douglas Hansen]

The idea that bonding is necessary at hydromassage tub motors has always been a solution in search of a problem.

[Jack Davenport]

...

[Jim Port]

680.74 Bonding. All metal piping systems and all grounded metal parts in contact with the circulating water shall be bonded together using a solid copper bonding jumper,

The

Jack, the tubs I have seen have plastic piping under the skirt for the circulating water to pass through. Do you still see the need for the motor to be bonded? The metal is not in contact with the circulating water. It is on the supply side. Once the tub is filled it is no longer touching the metallic pipes.

[Jack Davenport]

680.74 Bonding. All metal piping systems and all grounded metal parts in contact with the circulating water shall be bonded together using a solid copper bonding jumper,

The

Jack, the tubs I have seen have plastic piping under the skirt for the circulating water to pass through. Do you still see the need for the motor to be bonded? The metal is not in contact with the circulating water. It is on the supply side. Once the tub is filled it is no longer touching the metallic pipes.

Jim

I would say that if you have metallic piping feeding the faucets and plastic plastic piping for the recirculating water, then NO there is no requirement to bond the motor /pump to the metallic house piping feeding the faucets.

Is this what you wanted to hear or do you disagree?

[Greg Booth]

680.74 Bonding. All metal piping systems and all grounded metal parts in contact with the circulating water shall be bonded together using a solid copper bonding jumper,

The

Jack, the tubs I have seen have plastic piping under the skirt for the circulating water to pass through. Do you still see the need for the motor to be bonded? The metal is not in contact with the circulating water. It is on the supply side. Once the tub is filled it is no longer touching the metallic pipes.

Jim

I would say that if you have metallic piping feeding the faucets and plastic plastic piping for the recirculating water, then NO there is no requirement to bond the motor /pump to the metallic house piping feeding the faucets.

Is this what you wanted to hear or do you disagree?

........probably overthinking this, but - isn't there metallic contact within the pump (shaft, etc.) and the circulating water? And then wouldn't there exist a connection between the circulating water and those metallic piped faucets if the person in the tub reaches to add more water? Seems like maybe there should be a bond jumper between the pump lug and the supply piping?......Greg

[Jim Katen]

. . . probably overthinking this, but - isn't there metallic contact within the pump (shaft, etc.) and the circulating water?

No. There isn't. The water only touches plastic - at least in the one that I took apart.

[Jim Port]

I agree that no bonding would be needed with the plastic pipe. I could also make the same claim even with copper feeding the tub since it is not touching the circulating water.

[Jack Davenport]

I don't think the pump shaft is energized normally, unless of course, the windings are shorted to it, that's possible. So if there is 120 volts on the shaft, it will take the path of least resistance back to the source. It is not going to flow though a foot of water if it can take the metal path back to the junction box and the cable. But the rule isn't worded very clearly, I agree.

The current will take ALL paths to get back to the source, not just the path of least resistance. There may be more current on the path of least resistance but the will be current on all paths.

Saying that current will take the path of least resistance is incorrect and misleading.

[Jack Davenport]

Ok here's when you need to bond the hydromassage tub.

The requirement for bonding applies ONLY if you have two (2) things: (1) a motor that isn't double insulated and (2) a metallic water piping system. IF you have BOTH of these you need to bond them together. If either of those two items is not there you can't possibly bond them together since one of them is nonexsitent.

[Kyle Kubs]

Ok here's when you need to bond the hydromassage tub.

The requirement for bonding applies ONLY if you have two (2) things: (1) a motor that isn't double insulated and (2) a metallic water piping system. IF you have BOTH of these you need to bond them together. If either of those two items is not there you can't possibly bond them together since one of them is nonexsitent.

Just for extra clarity, since there seams to be a lot of mincing of words here, this applies regardless of the plastic circulating piping that is a component of the tub. i.e. if the tub has copper pipe feeding the faucet AND a pump that is not double insulated, it must be bonded to the metallic water pipe. The circulation piping being plastic (I've never seen it otherwise), just means that pipe doesn't require bonding, it doesn't make bonding the Copper feed pipe unnecessary.

And just for the record, water, normal household/city/well water, absolutely is conductive, unless you are somehow getting distilled water piped to your house. People do also have a tendency to use Epsom salts in their tubs as well, which raises the conductivity even more.

[Jim Katen]

Ok here's when you need to bond the hydromassage tub.

The requirement for bonding applies ONLY if you have two (2) things: (1) a motor that isn't double insulated and (2) a metallic water piping system. IF you have BOTH of these you need to bond them together. If either of those two items is not there you can't possibly bond them together since one of them is nonexsitent.

Just for extra clarity, since there seams to be a lot of mincing of words here, this applies regardless of the plastic circulating piping that is a component of the tub. i.e. if the tub has copper pipe feeding the faucet AND a pump that is not double insulated, it must be bonded to the metallic water pipe. The circulation piping being plastic (I've never seen it otherwise), just means that pipe doesn't require bonding, it doesn't make bonding the Copper feed pipe unnecessary. . . .

No. That is not correct. 680.74 only applies to metal piping systems and metal parts that are in contact with the circulating water. This is made a bit more clear in the 2014 NEC, where the first sentence has been changed to read, "All Both metal piping systems and all grounded metal parts in contact with the circulating water . . ."

The substantiation for the change reads as follows, "Substantiation: There seems to be much confusion with the present wording of this requirement. Inspectors and installers seem to believe that the two parts of the first sentence, All metal piping systems and all grounded metal parts in contact with the circulating water are two separate requirements. Because of this they take the first part All metal piping systems out of context and require the pump to be bonded to the hot and cold metallic water piping that feeds the hydromassage tub faucet. If the intention of this section were to take the first two parts of the sentence as two separate requirements then there would need to be some additional wording that would say exactly where the All metal piping systems that are required to be bonded are located within the structure. When taken as two separate parts, it would mean that every metal piping system within the structure would be required to be bonded to the pump motor. This would include the hot and cold metallic water lines, metallic gas piping systems and any other metallic piping system within the structure. changing the first sentence will clarify that the requirement is solely for metal piping systems and grounded metal parts that contact the circulating water and not the piping used to fill the tub or any other metallic piping systems that may or may not be in the vicinity of the hydromassage tub."

Read all about it here, on page 88:

https://www.nfpa.org/Assets/files/About ... ballot.pdf

HM tubs that have metal piping systems in contact with the circulating water are exceedingly rare these days. We're only likely to encounter them in very old installations or in homemade getups.