Hot tub couple electrical questions

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I have done a couple of hot tubs in the past, but not in many years, and I'm unclear on a couple things:
1. Bonding/grounding. I'm all set to pull 4 #6 (240v/50a) to the hot tub, which includes insulated ground and neutral. I am pretty sure the code says the ground needs to be as big as the hots. But do I actually need an additional ground as a 5th conductor (not insulated) to bond/run to cold water pipe? If so, I'm just not sure how this has to be set up? Also are modern units usually internally bonded or does bonding have to be done by the electrician/installer? Does any special bonding have to be done between the subpanel bushing and the enclosure/ground bus?
2. Can the GFCI just be an outdoor subpanel with a GFCI breaker in it for the hot tub and an additional breaker for the required GFCI receptacle, fed by a normal breaker at the main panel?
3. If so, and if I wanted to install a 60a subpanel, what amperage breaker do I need at the main panel? I don't need the entire 60 do I?
thanks for any help!
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mi partTime wrote:

Some of the newer packaged units do not require the neutral, and some do.

No. From a safety standpoint, this would be counterproductive. Nor is wise to drive a ground rod at the hot tub, as is sometimes done.

The grounding and bonding are two entirely different systems with different purposes.
Grounding for a hot tub is the same as grounding for any other appliance (with special requirements for added reliability). The purpose of grounding is to establish a ground reference for conductive metal enclosures and to provide a return path for ground fault currents.
Bonding refers to the practice of connecting together all metal parts of the pool, and nearby fittings, piping, metal conduit, and so on to eliminate any possible voltage gradients in the pool (hot tub) structure or differences among metal objects that can be touched by a person in the pool (hot tub).
Newer approved packaged hot tubs will be manufactured with bonding already in place for all the hot tub equipment. It will be up to you to bond to the bonding block inside the hot tub all metal conduits, piping, and large metal parts (usually taken to mean greater than 4 ins. in diameter) within 5 feet horizontally and 12 feet vertically from the water's edge or surface. The rules are the same as for swimming pools, and the 12-foot height seems a bit excessive to me, unless your hot tub has a diving board, but that is the rule.
The bonding and grounding systems should be connected together at exactly and only one point. Newer hot tubs are provided with a bonding block (often labeled "ground") for this purpose. The block is usually located in or attached to the control unit inside the hot tub. Occasionally there are two blocks, one for the electrical ground and one for bonding, and they will be connected together.
Bonding requirements are covered in 2002 NEC section 680.26, which I recommend reading if there are any nearby metal objects.

Not beyond the usual grounding methods. That is, metal conduit must be effectively grounded by an appropriate means, as usual. I suggest PVC conduit unless some circumstance or local requirement dictates otherwise.

Yes. This is how it is usually done. There are also special panels made for the purpose that have a built-in GFCI receptacle.

If you have a 50a, 2-pole breaker for the hot tub, and another 15- or 20-amp breaker for the outlet, I would suggest sizing the wiring for 60 amps and using a 60-amp breaker to feed the sub-panel. Although the hot tub requires a 50-amp circuit, it won't actually draw the whole 50 amps, so that you could probably get away with a 50-amp feeder, but you won't save much money.

--
Best regards, Tony
http://dotznize.com/electric
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Be sure that you need the neutral, my spa just runs on 220, didn't need a neutral. Ground must be insulated, but it can be sized down. So you could run a #8 green thwn wire for your ground. Don't run a 5th bonding wire. Check the owners manual of the spa to see what they say about bonding. I ran bare solid copper from the bonding lug inside the spa cabinet to the water spigot near the spa. Bonding only need to be done if there is any metal closer that 6' to the spa. I ran my bond wire on the outside of the electrical conduit feeding the spa. I used zip ties to attach this wire to the outside of the conduit. My hookup passed inspection.

Yep. Or you can put the GFCI in your main panel, and run the wiring to an A/C pull box, rated for 60 amps, mounted near the spa. This is what I did. It saved a few bucks. But then the GFI breaker is inside the main panel, and not next to the spa. Could be a PITA if you have breaker tripping problems. So far, I have not.

You'd need a 50 or 60 amp breaker. I'd go with 60. You don't want the rating on that breaker to be less than the rating of your GFCI breaker, or it will trip if the spa pulls a lot of power.

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Just helped my brother install his spa. I was flatly amazed at the wiring methods. There was a plastic pipe stubbed out for the connection. There was a plastic panel with 4 connection, 2 hots a neutral and a ground. He has a radio/cd player so he needed the neutral. Better check with the manufacture or sales guys for exact requirements. We ran 6 for the phases and 8 for the neutral and ground. A little over kill, but it was 150 feet from the service and bro did not want any voltage drop. Your ground idea works well with circuits below 30 amps, above 30 amps it is common to use the tables in the NEC for sizing.
All pools and spas require the ground to be UNBROKEN from service to load. This can be tricky with a sub panel. Unless you put the GFCI breaker feeding the panel in the subpanel. We put the GFCI in the service. Yes a regular breaker can feed a GFCI. Required receptacle? Required by whom?
The size of the feeding breaker depends on the load. There is no difference in price between a 50 or 60 amp breakers.
You must bond all metal within I believe 6 feet from the water. This will be run back to the subpanel. NOT a water pipe. Connecting to a water pipe creates a ground loop.... can be very bad.. Water is already grounded at the service. This and the improperly installed ground rod are very common mistakes.
Have fun with your new toy. Bro sure does
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Thanks for pointing that out, now that I checked, I'm reading from {NEC 680.43 Indoor Installations} where it requires a GFCI recept within 10 ft of the tub. However this tub is outdoor. Can anyone verify that this recept. is not required for outdoor installation?

I'm still unclear on how the unit and its subpanel has to be grounded, which to me is of the utmost importance. All the unit's diagrams show that the insulated ground is terminated at the supplied block in the unit box. My question is does "unbroken" mean it can't be "broken" at the grounding block on the subpanel enclosure, then continue back to the main panel? This is how I have done it in the past. Otherwise, I don't understand how the subpanel enclosure can would be grounded. Then at the main panel, don't the neutral and ground connect to the same lug? in other words, I thought the subpanel is supposed to "float" the neutral but not the ground.
As far as ground rods, I'm having trouble finding anything in the NEC that says anything about additional ground wires (besides the insulated ground mentioned before) or ground rods for that matter, separate from the service ground rod.
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snipped-for-privacy@ameritech.net wrote:

We had a hot tub installed outdoors on our deck last October and the town required that we had a GFCI outlet no closer than 10 feet and no further than 20 feet from the hot tub. We already had the GFCI outlet in the 10-20 foot range and the only extra they required on it was that we put a new cover over it that allows the outlet to be covered while something was plugged in. This is northern New Jersey so don't know if your requirements would be the same.
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This is correct according to NEC - you must have an outlet within 20', but no closer than 10' of the tub or swimming pool.
(Not "within 10' !)
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Looking at my code book, this GFCI receptacle is only required for indoor spa installations, I asked the local inspector and they don't seem to have any local code that requires it either. I think for pools it is required.
I keep hearing people mention ground rods and bonding for the tub, but it seems strange to me because I would assume that: 1) The modern units' parts are all sufficiently bonded from the factory and 2) that the insulated ground that is coming from the main panel>subpanel>tub would take care of it and eliminate the need for an additional ground rod.
wrote:

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As I recall, there also was a reqt for an outdoor spa was to have a disconnect located within a specified distance of the spa to allow for emergency shut off. That's how mine is done, I have a fused disconnect located about 6 ft from the spa, with the GFCI back at the main panel.
My spa came with all of the internal metal parts bonded together with a heavy gauge bare wire. The only thing left to do was connect the incoming ground wire to the supplied ground wire of the unit. If you have any other metal within the nearby radius of the spa, eg ladder, water pipe, etc., then that would need to be bonded to the other metal bond path in the spa.
As far as needing the neutral, I would run one even if the spa doesn't need it so that it's available if a future spa does.
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On 02 Apr 2004 23:33:50 GMT, snipped-for-privacy@aol.com (HA HA Budys Here) wrote:

Hmm... Wasn't required for my spa. Just a cutoff switch within view and no closer than five feet to the water. But I won't guarantee the inspector didn't just miss it.
Jeff
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Bonding is not grounding. Any metal near the hot tub must be connected to the bonding lug on the hot tub. About the only things most people have would be water spigots, gutter downspouts, and maybe metal posts or conduits. These must have a #8 solid copper wire run back to the bonding lug. If you have no metal near the hot tub, then no bonding grid is required. This bonding grid does not have to go to the ground bus either. There is typically an incidental ground somewhere in the hot tub (usually the pump motor) that connects the green ground to the solid #8 bonding grid, but you don't need to make this connection yourself.
The grounding wires are allowed to be spliced except for the branch circuit that serves an underwater light. If your spa disconnect is near the tub and contains a breaker, the wires going from the house to the disconnect are a feeder. This must have an insulated grounding wire and must be run in conduit, but splices ARE allowed. If there are breakers in the hot tub, then all of the wires leading to the tub are considered a feeder.
So forget about the spliced ground confusion, as it sounds like you know how to ground the disconnect enclosure.

If your spa disconnect is in or at a separate building, that building must have a grounding electrode which connects to the disconnect box. No additional grounding electrodes (rods) are otherwise required.
-- Mark Kent, WA
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How can the connection between all the metal parts which are grounded together and the ground from the electrical service be "incidental?" If these are not deliberately brought together at the spa, then a short from hot to the metal case of, say the heater, will result in the entire bonded metal system being hot without tripping a breaker.
Also, it's incorrect to say that unless you have metal near the tub, no bonding grid is required. It's true no external bonding is required, but internal to the spa, all metal components, ie pump, heater, control pack, etc are still bonded together in every spa I've ever seen.
The grounding wires are allowed to be spliced except for the branch circuit

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Its semantics again. In a factory hot tub assembly, the factory decides where it wants to run an equipment grounding conductor and a bonding grid conductor. The equipment grounding wire will typically be #12 or #10, and will connect to metal items that have electrical wires attached (like pumps, heaters, electronic controls enclosures, etc). However, it is possible for the pump to be plastic and double insulated, and the controls electronics can be in a non-metallic box. In this case, there would be no equipment grounding conductor run because there is nothing to ground.
The bonding grid is required to connect certain things, such as metal pumps. If the tub was totally non-metallic, the bonding grid would connect to the pump motor frame (if metal), and any metal pieces on the outside of the tub greater than 4 inches square. This bonding grid must be done with #8 solid copper wire.
So yes, you can say everything is bonded, but if #12 copper was used it is not part of the "bonding grid". There is no requirement that the bonding grid be connecting to the equipment grounding conductor. However, that usually happens because some items are required to have both an equipment grounding conductor and the bonding grid conductor.
-- Mark Kent, WA
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My main point was that any metal that is bonded together at the spa is not "incidentally" connected to the AC ground, relying on some chance connection. It must be deliberately connected, otherwise with a short, the entire bond path would become hot.
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The NEC requires a GFCI outlet no closer than 10' but no farther than 20' to service your spa, even one outside. Check with your local electrical inspection authority if you have questions there. They are the final word on that type of thing.

Run your green insulated ground wire from the ground terminal in your spa electrical panel thru your conduit and to the ground bar in your sub panel. Then you must run a ground wire from that sub panel back to the main service panel ground bus. That's all you need to do for grounding. The ground and neutral bars in your sub panel should be seperate, so make sure you connect the ground wire to the ground bar, not the neutral bus. In your main panel, the ground and neutral busses are connected (bonded), so it doesn't matter which you connect to. Do not install a ground rod for your sub panel.

You do not need a seperate ground rod for a spa sub panel. If you had a sub panel installed in a building that was physicall disconnected from the building housing the main panel, and that means no metal pipes, etc...Then you'd need to install a ground rod. For you spa panel, as long as it is attached to the structure which contains your main service panel, you do not need a ground rod. That would violate NEC code.

a connection between the bonding terminal on your spa, and any metal within 6' of the spa, such as a water spigot.
If you still don't understand this, then get an electrician out there to help you. Spa and pool wiring is complicated, and it is not uncommon for even professional electricians to get dinged on the initial inspections.

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That pretty much clears it up for me, thanks for the concise explain. According to local inspector, there is no need for the GFCI recept. but I'm putting one in anyway for convenience.
There is one other question that has cropped up: On the run from main to subpanel that will contain the GFCI breaker for the tub, I will need to make a run to a junction box first before it goes out through the wall. I was planning to run (4-wire) #4 THHN in a run of 1" flex, through the j-box on the inside, continuing the feed outside to the 60a subpanel. Someone told me they thought that feeders for a subpanel had to be in EMT or better, which I was almost sure was wrong, because I could swear I've wired subpanels this way before (many years since I worked as apprentice.) I also can't seem to find the relevant section in NEC. I'd use EMT but the access is very tight and the bends would be more work than I care to do.

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mi partTime wrote:

#6 THHN (copper) is more than adequate for a 60A circuit, and you avoid some of the rules about bending room for #4 and larger in that J-box. I think you could run three #6 THHN's and a #8 bare copper equipment ground in a 3/4" conduit if that would be easier in the tight space.
I don't know of any rules about "EMT or better". There is a rule about not using EMT in contact with the ground if that matters.
Best regards, Bob
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Thanks, you are correct, it looks like #6 AWG copper is rated for up to 75a with THHN.
The person just said "you can't use flex conduit for feeders for a subpanel" and I thought maybe he had it confused with main service or something. I'd prefer EMT if there was more room to work. I'm probably going ahead with flex unless I can find something in the code that prohibits it.

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Normally, feeders can be run with NM cable, or any of the raceway methods. However, hot tubs have to follow swimming pool rules in parts I and II of NEC 680. Swimming pool feeders (NEC 680.25) specify that these feeders use PVC, Liquidtight Flex, or IMC/Rigid conduit. Inside the house, you can use EMT or ENT too. I believe the intent here is to provide the best protection as you can to the conductors. The only exception to this is existing installations inside the house -- they can use flex or a cable with a covered grounding wire, but it has to be an old installation. Regardless of the raceway type chosen, you must run a green insulated grounding wire.
I think you'll be happier with #6 THHN wire (and a #8 copper ground), but you can't use it above its 75C rating because you won't find any circuit breakers or neutral bus terminals rated above 75C (or at least they are very rare). This means you can still have a 65A circuit on that #6. Since 65A isn't a standard size, you could put a 70A breaker in the main panel and then put a 50A DP GFCI for the spa and a 15A breaker for your 120V GFCI receptacle. You'll need a 4 slot panel in this case. Also, with #6, you must use proper colored ground and neutral wires (green and white). You can't tape the ends of wires sized #6 and smaller for neutral and ground.
-- Mark Kent, WA
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680.25 Feeders. These provisions shall apply to any feeder on the supply side of panelboards supplying branch circuits for pool equipment covered in Part II of this article and on the load side of the service equipment or the source of a separately derived system.
What's confusing to me is if this applies to hot tubs? Because it refers to "pool equipment covered in Part II of the article (Permanently Installed Pools), I was unsure.
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