disconnect for spa required?

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  #1  
Old 05-14-06, 02:38 PM
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disconnect for spa required?

I've got a 120V, non-gas spa that I'd like to put into use. The unit will run off a 20A dedicated circuit. The unit is not hardwired; it is equipped with a plug in it's enclosure, which goes to a receptacle that has been installed. So no hard wiring.

2 questions:

1) in this case, do I need a disconnect? The primary means of disconnect in this case would be the plug.

2) Does the receptacle/circuit need to be GFCI? Let's assume that the unit is not equipped with an internal GFI mechanism.

Thanks all !
 
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Old 05-14-06, 03:20 PM
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1) in this case, do I need a disconnect? The primary means of disconnect in this case would be the plug
.yes
2) Does the receptacle/circuit need to be GFCI? Let's assume that the unit is not equipped with an internal GFI mechanism
.if the spa does not have a GFCI plug already (many are coming like this), yes it does need to be GFCI.
 
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Old 05-14-06, 03:24 PM
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thanks for the reply. Easy enough to do. Probably will go with a GFCI breaker rather than the receptacle, as it's a pain to disassemble the enclosure (if I get a nuisance trip).

What is the max distance between the disconnect and the spa?

Thanks again !
 
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Old 05-14-06, 03:36 PM
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Originally Posted by fuente
thanks for the reply. Easy enough to do. Probably will go with a GFCI breaker rather than the receptacle, as it's a pain to disassemble the enclosure (if I get a nuisance trip).

What is the max distance between the disconnect and the spa?

Thanks again !
minimum is 5 feet from the inside of the tub if it is GFCI, locking type, grounding type and a single receptacle. If it doesn;t fall within those guidlelines it needs to be at least 10 feet from the tub and in either case no more than 20 feet.
 
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Old 08-14-06, 09:51 AM
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I’d like to revisit this one…

2005 NEC section 680.41 states that sps and hot tubs must have an emergency cut off switch. The last sentence states ‘This requirement shall not apply to single family dwellings’.

I have a hot tub on a GFCI protected, 20A dedicated circuit. It’s not hardwired. No local disconnect, yet. If one is required I can install it, but looking at the code, it doesn’t look like it is. The primary shutoff would be the plug connection, secondary of course would be the breaker.

If another code section applies, I’d appreciate a reference. Thanks.
 
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Old 08-14-06, 10:02 AM
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The cord and plug function as the cut off. No additional cut off is needed.

Yes, you do need GFCI protection.

Is this inside or outside?
 
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Old 08-14-06, 10:15 AM
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That’s what I thought after reading the code. It’s outside.
 
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Old 08-14-06, 10:52 AM
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If the hot tub is outside and the plug is outside then remember that you must have an insulated ground wire. No UF cable allowed or uninsulated ground wire.
 
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Old 08-14-06, 12:04 PM
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Originally Posted by racraft
If the hot tub is outside and the plug is outside then remember that you must have an insulated ground wire. No UF cable allowed or uninsulated ground wire.
Are you quoting 680.6? If so then only wiring within 5 feet of the hot tub, not all wiring going to the hot tub. My plan is to run conduit between the spa plug and the j-box feeding it. This run is mostly inside the enclosure, when makes sense because water may be (hopefully not) present. The j-box feeding the plug, however, is more than 5 feet away from the spa. The wiring to that J-box from the interior of the house is UF. I believe 680.6 allows for this.
 

Last edited by fuente; 08-14-06 at 12:20 PM.
  #10  
Old 08-14-06, 02:20 PM
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The code is all wiring outside the dwelling must be in an approved conduit... not just 5 feet from the spa. Inside you can have NM-b or Uf if you want. The transition to conduit is made in a junction box inside or at the disconnect if mounted on the dwelling. The bare ground cannot extend outside.... it must be insulated once it leaves the dwelling.
I just finished an above ground permanent pool where the customer also had a hot tub. He wired the tub himself... all uf-b #6 cu. Had the uf run across the surface of the concrete patio till it entered the hot tub about 10 feet from the dwelling. Had a gfci 50 amp spa panel on the outside wall but this was a package pool with integral gfci. Costly redundancy.

Roger
 
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Old 08-14-06, 02:43 PM
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Well, I don't have that so I guess I am not in compliance.
 

Last edited by DIYaddict; 08-14-06 at 02:52 PM. Reason: Removed quote/Quoting the entire post is unnecessary
  #12  
Old 08-14-06, 05:16 PM
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The approved conduit types are RMC,IMC,RNC, and type MC cable that is listed for the application. You can use EMT but it must remain either in or on the dwelling. In all cases once you leave the dwelling you must run an insulated equipment grounding conductor no smaller than #12 awg copper in all types of these listed conduits.

roger
 
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Old 08-14-06, 07:15 PM
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I understand this, but what is the reasoning for it? Just trying to figure out why the conductor must be insulated just because it is feeding a hot tub, pool, etc. Thanks.
 

Last edited by DIYaddict; 08-15-06 at 11:20 AM. Reason: Removed quote as it's unnecessary
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Old 08-14-06, 08:05 PM
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You could install a blank face GFI device to provide the protection. Install this on the wall so you don't need to remove the skirt if it tripped. Just install a regular duplex under the skirt.
 
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Old 08-14-06, 08:35 PM
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I already have a GFCI receptacle installed under the skirt for the hot tub plug. The hot tub also his an internal GFCI on the pump. The skirt takes 10 seconds to remove and put back on, so no worries there.

Is the insulated ground wire a recent addition to the NEC? I'm thinking this:

If the hot tub's internal GFCI fails, AND the receptacle GFCI fails, then the ground needs to be intact back to the panel.

But UF is designed specifically for this. But UF can be damaged (don't know how just the ground could be and not the other conductors, but ok) by some kind of equipment; conduit usually cannot, or is more difficult to.

Ok, so if there is a fault and the hot tub GFCI fails..AND the receptacle GFCI fails, AND the UF has been damaged BUT only the ground wire (because if any other conductor was damaged the hot tub would not work), then the fault cannot get back to the panel, the breaker cannot trip, and I'm dead.

Is this the logic that the NEC has used to make this requirement?
 
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Old 08-15-06, 05:18 AM
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fuente,

The requirements for an insulated ground wire is not new.

I have never heard (on this forum or anywhere else) any rationale for this insulated ground wire that really makes sense.

Nevertheless, it is a requirement and must be followed.
 
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Old 08-15-06, 07:54 AM
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Thanks Bob. The one thing I absolutely hate is doing something for no good reason at all. As an engineer my mind does not work that way.
 

Last edited by DIYaddict; 08-15-06 at 11:19 AM. Reason: Removed quote as it's unnecessary
  #18  
Old 08-15-06, 11:16 AM
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In my opinion its all about reducing the ways faults can be imposed on the ground wire and corrosive influences. If you think about some of the fault possibilities if you had an open ground in the pump branch circuit from damage or other reasons, they dont like the idea of the increase in risk of this occurring outside the dwelling if the ground is bare. An Insulated ground would offer a degree of protection from being energized on the spa/pool side of the open. A gfci might catch this type fault hopefully. I dont think it is relevent to try and say that it's overkill or has no purpose if it even has the slightest chance to provide an increase in safety. Code is usually minimums so you could always require even more be done to a pool for single family dwellings like they do for commercial pools and spa's.

Roger
 
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Old 08-15-06, 11:22 AM
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Roger, could you walk me thru how an insulated ground differs from a bare ground? I'm not following. Thanks.
 
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Old 08-15-06, 11:36 AM
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My point is an insulated wire will not allow a short to be imposed on it but a bare wire will. Though remote you could energize the case of the pump and possibly the pool wall if the ground is open. That possiblity increases if the wire is bare. There is a greater chance of this happening outside the dwelling.
 
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Old 08-15-06, 11:41 AM
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Originally Posted by Roger
My point is an insulated wire will not allow a short to be imposed on it but a bare wire will. Though remote you could energize the case of the pump and possibly the pool wall if the ground is open. That possiblity increases if the wire is bare. There is a greater chance of this happening outside the dwelling.
A short with what? Another conductor inside the UF?
 
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Old 08-15-06, 12:09 PM
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Originally Posted by Roger
My point is an insulated wire will not allow a short to be imposed on it but a bare wire will. Though remote you could energize the case of the pump and possibly the pool wall if the ground is open. That possiblity increases if the wire is bare. There is a greater chance of this happening outside the dwelling.
How is this even remotely possible? The ground, while not insulated, is within the jacket of the UF, and is no where near the pump casing. The receptacle box is probably 1 foot away, inside the enclosure. I could see if the UF was wrapped around the pump casing or the inner tub wall, but that’s just plain crazy. Even then the outer jacket of the UF would need to be breached to create this situation. If the jacket is intact then nothing would happen.

And why is there a greater chance of this possibility outside the dwelling? If a ground is bare and is open, it basically becomes a conductor, whether inside or not. Are you saying that a ground has a more likely chance of becoming open outside of the dwelling? If so, what is the reasoning?

Thanks.

Still not following.
 
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Old 08-15-06, 12:09 PM
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You cant use uf outside for the branch circuit but yes to some other conductor in the conduit. Lets say the conduit gets damaged and a hot wire is broken and the ground is open downstream from the damage or at the damage site. If the ground is insulated... contact with the hot wire causes no fault to occur and the hot tub just quits working. However if the ground is bare and it contacts the hot wire a fault is allowed. If the ground is open and the contact is pool side of the open ground... current will flow to the hot tub or pool pump on the ground wire and from the pool pump bond to the walls of a pool or metal parts connected to the hot tub bonding #8. No breaker will trip cause the fault path back to the panel is broken, you just energize the metal parts due to the fault. Not likely but possible. Alot of the safety design in this hot tub and pool circuitry is accident investigations and what causes them so they are trying to reduce those faults that have been determined to cause injury.
 
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Old 08-15-06, 12:21 PM
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If the hot wire is broken, then how does the hot tub continue to work? You’d know right away if the hot was severed.

Anyway, no way does the pump get energized when the closed J-box is 1 foot away from it. If the ground wire was hot at any point and also open, it is still A) in the UF sheathing, and B) no where near any metal parts. Can you provide a scenario where this could actually happen in real life, not theory? In theory I agree, but not in real life. I’m also failing to see if how if the hot was open, it would not de-energize the pump immediately.
 
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Old 08-15-06, 12:48 PM
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Ok I'll do my best. I am not talking theory now or at anytime in these posts. Your uf goes to the receptacle in the hot tub enclosure, where the ground wire of the uf is terminated on the receptacle and to the metal Jbox. You then have a cord that plugs in from the pump to the receptacle if I understand your situation for your hot tub. That cord has a ground wire in it..... (unless this is a double insulated pump)... this is uncommon on a hot tub pump from my experience.
That ground wire in the cord then goes to the the pump motor and is terminated to the pump motor metal case. On the outside of the pump case is the bonding lug that the bonding #8 is connected to and then connects to all the metal grid of the hot tub. So follow the current in this screnario.
Your stalling on the fact that nothing can go wrong with that uf with bare ground. It is not listed to be providing physical protection only a conduit can do that.

Yep, the pump quits working what you dont know is the metal of the pump and hot tub frame/parts is energized at line voltage.

I'm saying that physical damage is more likely to occur outside... an open ground has many possibilities inside and out.
 
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Old 08-15-06, 01:07 PM
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Ok, I follow you now.

So if A) the hot is damaged and either B) the ground is damaged at the point or somewhere downstream and C) becomes energized, then the ground is now hot and the pump casing will become energized. The ground is no longer protecting the circuit because it has been severed, so no trip of the breaker.

My hot tub unit has an internal GFCI. Wouldn’t that trip if the ground became energized? What about the GFCI receptacle? That should trip also for the same reason?

The bigger common sense issue is that the hot tub would stop working. If this is the case, before I touched anything I would check to see if it’s energized. Stupid not to. Maybe the future homeowner would not, but I would. Always.

The more likely, overwhelmingly, scenario is that you drive a shovel into the ground, and pierce the UF. If you’re stupid enough to do this with the circuit hot, or if you don’t know there is UF underground, then you’ll get shocked and, well, you can fix the problem from there.

If you have the circuit off, and severed just the hot (not probable) then when you turned the circuit back on and checked the hot tub and saw it was de-energized, well, only one thing could have caused that. And you fix the problem from there.
 
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Old 08-15-06, 01:26 PM
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Originally Posted by fuente
Anyway, no way does the pump get energized when the closed J-box is 1 foot away from it.
Incorrect. The ground wire is internally connected to the motor casing, to force it to be at ground potential.

Bottom line. Here is what Roger is stating:

It is easier to have a fault between the ground and a hot conductor with a bare ground than with an insulated ground. I agree with this.

It is easier for a cable that is outdoors to get damaged than for cable that is indoors. I suppose that I agree with this, but of course it all depends on HOW the cable is routed, etc.
 
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Old 08-15-06, 01:29 PM
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Yes I do agree with what you say. I think you have to look at the fact that other people may not due as you would do, children etc... If the uf is buried at the proper depth very remote that you would have a problem but none the less overtime who knows. Code still requires the insulated ground. I believe they have their reasons (I will try to querry for the answer in better detail).
I'm only trying to disuss a fault that I feel may be relevant to why the insulated ground is required. I may well be off base in my thinking but thanks for having the patience to hear me out.

Its the odd.... never thought could happen....thing that seems to be the one that causes the most harm.

I'm not sure the gfci would detect this type fault everytime. I believe though it would catch it most of the time and trip out. I can see where there would be no current differential though allowing the gfci to stay holding. I would have to spend a little time thinking about it.

The gfci will trip on current leakage normally in the milliamps somewhere above 5 or so. A short will trip the breaker but not the gfci in most cases. Many times the gfci is destroyed if short currents are passed thru its circuitry. I've watched this demostrated by some of the square d people at one of there product programs.
 
  #29  
Old 08-15-06, 02:18 PM
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Yep, I see that now Bob. The plug's ground becomes energized via the receptacle.

Thanks Roger for having patience with ME to explain this.
 
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