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Old 03-25-2008, 02:43 PM   #16
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If the neutral opens the the jacuzzi stops working but it will not harm the breaker. If the neutral shorts to ground then the non-gfci breaker will not open as Inphase77 has already said. However the emt will start carrying the neutral current back to the service panels neutral bar. This is a bad situation and can cause a shock hazard to people.

If the neutral shorts to a phase wire then the breaker will open due to the inrush of current coming thru the breaker.

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Old 03-25-2008, 02:51 PM   #17
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An interesting thing for your thoughts....when a gfci receptacle is shorted hot to neutral or ground load side of the receptacle the gfci receptacle will destroy itself most times but it will not trip out. The breaker in the service panel trips out on the overcurrent. Remember a gfci detects small milli amp leakages not overcurrent. If you have a gfci breaker same thing likely will happen the breaker trips on overcurrent the gfci portion will not cause the trip.
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Old 03-25-2008, 02:56 PM   #18
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Quote:
Originally Posted by capndave View Post
Big thanks to the inventors of GFI breakers. I only used the jacuzzi once,
for about 15 minutes, and suspect it arc'ed while I was in the tub.

For academic purposes - What do you guys think would have happened in this
specific situation if it was a non-GFI breaker, with a neutral short?
With just a neutral-to-ground short? Most likely, nothing, but... If the neutral ever opens, say from temperature expansion across the damaged section, then the current that wants to return on that neutral may find another path, perhaps through a person stepping out of the hot tub onto concrete.

If wiring were fool proof and every installation could be guaranteed to stay intact forever, then we wouldn't need GFCIs. But that isn't the case in the real world. By protecting the wiring at it's source we can give a measure of protection to cover cases where the unknown could happen.

I might mention that the 1/2" conduit is still slightly overfilled. I wouldn't lose any sleep over it, but if you wanted to be picky, you could show the electrician the calculation and insist on making it right. This would allow you to have new wiring installed to alleviate the nicked neutral problem. This is why we don't overfill. It's bad enough when you have the right number of wires in the pipe, but overfilling increases the risk of damage that much more.

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Old 03-25-2008, 03:40 PM   #19
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The 240V circuit should be 240V only with no neutral present. There should only be hot wires attached to the breaker and the 240V receptacle and a green jumper between the receptacle grounding screw and the box. There should be no neutral attached to the GFCI breaker.

If the electrician wired a white wire to the receptacle grounding screw, he is definitely at fault.
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Old 03-25-2008, 04:58 PM   #20
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HouseHelper. This is a conduit-based grounding system. The circuit is for a jacuzzi tub GFI-breaker at the panel. I know the A/C 240 , for instance, doesn't require a neutral since it isn't GFI. But I was under the impression
a 240v GFI-breaker requires a neutral returning back to the breaker itself -and- to the bus bar via the pigtail.
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Old 03-25-2008, 05:06 PM   #21
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Quote:
Originally Posted by capndave View Post
HouseHelper. This is a conduit-based grounding system. The circuit is for a jacuzzi tub GFI-breaker at the panel. I know the A/C 240 , for instance, doesn't require a neutral since it isn't GFI. But I was under the impression
a 240v GFI-breaker requires a neutral returning back to the breaker itself -and- to the bus bar via the pigtail.
It is necessary for the pigtail to be connected to the neutral bus, but the breaker does not require a neutral if the load is 240V only.
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Old 03-25-2008, 05:10 PM   #22
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No.. Househelper is correct. That is why I was asking where the gfci was located in that ealier post. If it was located at the jacuzzi then a neutral would have to be ran to the Jacuzzi location. If it is located in the panel then you would just connect the pigtail to the neutral bar and no neutral would connect to the neutral lug on the gfci breaker if it has one.
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Old 03-25-2008, 05:31 PM   #23
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Quote:
Originally Posted by InPhase277 View Post
capndave,

If the neutral wasn't installed properly on the breaker, then this could have been the source of the trip. However, this would mean that the breaker never would have stayed on for long enough to arc. If the neutral was damaged during installation, this could also cause the GFCI breaker to trip, and when the non-GFCI breaker was installed everything would still work properly, because a neutral-to-ground short won't cause an ordinary breaker to trip. This is what I suspect the problem is.

Another thing, if the breaker cost you $200, then someone is really ripping someone off. All electricians put a mark up on materials, but yikes!

InPhase277
Breaker could be tripping due to ground fault. Won't be detected by temping a standard breaker. A standard breaker would hold.

$200.00 for a 240v GFI breaker not too bad - what if this is a Federal panel?
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Old 03-25-2008, 05:39 PM   #24
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I think we've clarified something Quite significant here.

Let's just clarify the facts one more time and then I think we have it.

Here are how the electrician has wired it up.

1) A 240 V, 20amp, GFI breaker at the panel.
Here is a link to the exact breaker:
http://www.apelectricshop.com/p-478-...t-breaker.aspx

2) A 2-pole, 20amp, 3-wire grounding receptacle.
Here is a link to the exact receptacle:
http://electrical.hardwarestore.com/...le-601117.aspx

3) Two 12-gauge, THHN insulated hots going from the breaker to the receptacle.

4) One 12-gauge THHN insulated white going from the GFI breaker to the grounding screw on the receptacle.

5) The receptacle is mounted to a steel box, which is, in-turn, grounded back to the panel via a conduit-based system.

6) The jacuzzi ran one time, for 15-minutes and was fully operational.
After (or during) this run, the GFI breaker arc'ed.

So based on the last few replies -- This is incorrect?
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Old 03-25-2008, 05:42 PM   #25
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#4 is incorrect. Where does this wire terminate at the other end?
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Old 03-25-2008, 05:52 PM   #26
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Househelper

I believe his last says from the gfci breaker to the ground screw of the receptacle at the jacuzzi. Which is incorrect. However that would not cause the gfci to arc and destroy itself IMO.
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Old 03-25-2008, 05:54 PM   #27
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Quote:
Originally Posted by HouseHelper View Post
#4 is incorrect. Where does this wire terminate at the other end?
This is the sticky point, as I'm going from memory (the electrician took the faulty breaker). I really wish I could remember 100%.

I *initially recalled* that he returned the neutral to the neutral-bus - ie., the pigtail was not connected to anything.

However, I think it is more plausible that the neutral was returned to the panel via the GFI breaker - and the pigtail was connected to the neutral bus.
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Old 03-25-2008, 05:58 PM   #28
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Quote:
However, I think it is more plausible that the neutral was returned to the panel via the GFI breaker - and the pigtail was connected to the neutral bus.
I agree that is more likely. I still stand on a overcurrent fault causing the gfci to go.... poof.

And now that you say that neutral was run to the ground screw I'd bet dollars to donuts there was a short to that wire or to the emt that fried the gfci from overcurent amperage.

No having said that I'm not sure how you prove it. The electrician doesnt sound to up to forkin out the dough for a new gfci.

Last edited by Stubbie; 03-25-2008 at 06:06 PM.
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Old 03-25-2008, 06:27 PM   #29
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great reading guys. I just want to add that if the hot tub is outside (a/c wires in conduit) it now shall comply with 680 Part two. 680.23 (F)3 basicly the A/C needs to be on a gfci to meet this. (assuming hot tub has lights).
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Old 03-25-2008, 06:37 PM   #30
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Brad this is a Jacuzzi..... it is indoors and is classified as a Hydromassage Bathtub. I falls under Part VII of article 680. It is not required to comply with 680 Part II.

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