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Old 03-25-2008, 07:03 PM   #31
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Conduit Fill & Ampacity


stubbie: Part4 spas and hot tubs 680.42 "a spa or hot tub installed outdoors shall comply with the provisions of Parts 1 and 2 of this article". I think may have my teacher on this one. I did drink two cups today.

great info on gfci by the way.

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Old 03-25-2008, 07:28 PM   #32
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I spoke to a local electrician about our local grounding and neutral requirements for indoor jacuzzi tubs. I am told the original electrician was,
at the most, partially-correct, by running a wire from the 240 receptacle
back to the panel. It seems Local code requirements do not allow
grounding of Jacuzzi's via conduit and a hard ground must be run back to
the panel.

So, the electrician essentially stumbled into a degree of correctness here,
because he clearly did not intend to Ground the receptacle because he (a) chose white wire, and (b) most likely tied it to the GFI.

Since the neutral bus on my panel is also bonded to the panel ground, via
a bonding screw, the White wire was indeed grounded up until the point
the breaker fried. It is likely still grounded, via the conduit.

However, the correct wiring (according to local code) is:

a) Two hots from the GFI breaker to the receptacle.
b) Run a Green wire, from the receptacle to the neutral-bus bar -or- a grounding bar mounted to the panel.
c) Connect the GFI breaker's white pigtail to the neutral-bus bar.

The fact that the old breaker did in fact ARC, was probably the results of

a) A bad breaker.
b) A cut in the wiring (short) - likely from forcefully pulling through over wired conduit.


The solution for this mess is:

a) Separate the A/C and Jacuzzi conduit. 46% isn't helping matters.
b) Pull new wire for both Jacuzzi circuits.
c) New GFI-breaker on the Jacuzzi's 240 circuit.
d) Hard-ground the receptacle back to the neutral-bus bar.
e) Pigtail the GFI to the neutral-bus bar.

If this all sounds fine, we can call it a-day. Lots of expertise on this forum. I am really impressed.
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Old 03-25-2008, 07:32 PM   #33
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Quote:
Originally Posted by brad 134 View Post
stubbie: Part4 spas and hot tubs 680.42 "a spa or hot tub installed outdoors shall comply with the provisions of Parts 1 and 2 of this article". I think may have my teacher on this one. I did drink two cups today.

great info on gfci by the way.
Just to clarify, this is an indoor spa tub.
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Old 03-25-2008, 07:41 PM   #34
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Yep... I agree to all of that.

I'm a little perplexed that the electrician would connect to the ground of the receptacle and then to the neutral lug of the gfci. I would think that he would know that you never connect neutral to equipment ground like that.

I would be more likely to think that he just used a white wire instead of green for whatever reason and connected to the bonded neutral bar using the white as his equipment ground.
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Old 03-25-2008, 09:24 PM   #35
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Conduit Fill & Ampacity
I am hoping a licensed electrician can provide answers, given the following scenario.

- A single 75 foot run of 1/2" EMT Steel Conduit.
- 9 Wires Total (Three 8ga., Three 12ga, Three 14 ga.)
- The 8 ga wires feeds the residential air conditioner.
- The 12 ga wires feed the jacuzzi tub's blower motor.
- The 14 ga wires feed the jacuzzi tub's heater.
VERRY IMPRESSED YOU KNEW THE SIZES AND GUESED APPROXIMATLEY HOW MANY WIRES WERE IN THE CONDUIT WITHOUT ACTUALLY LOOKING AT IT.
Question 1:
What is the percentage of conduit fill for that run of conduit?
According to some basic calculations, it is significantly
over-wired.
MOST HOMEOWNERS DONT EVEN KNOW ABOUT CONDUIT FILL IMPRESSIVE!
Question 2:
If the conduit is indeed over-wired, what are the practical risks or drawbacks?

Question 3:
I have come across the term "ampacity", but I am not digesting
how it applies to over-wiring of the conduit. Can you please
explain the correlation (if any)?
KNOW CONDUIT FILL BUT NOT AMPACITY?
Thank you

Correction:

There are two 8 ga., not three. There are two 14 ga, not three.
YOU FINNALY HAD TO LOOK! YOUR NOT THE AVERAGE NORMAL D.I.Y. HOMEOWNER.
The entire home (Illinois) is grounded via the steel conduit. We don't use Romex. SIDE NOTE JUST CHICAGO AND OUTLINING COUNTYS REST USE ROPE.

I didn't wire this, the electrician did. I am a homeowner, in the middle of a spirited 3-way debate with my builder and the electrician. The jacuzzi's GFI breaker ($200) arc'ed and the electrician is distancing himself from the situation. I'm trying to be fair and not just an angry homeowner.

The 240v/20amp is a GFI breaker (jacuzzi blower).
The 120v/20amp is a GFCI receptacle (jacuzzi heater).
The 240v/40amp (air conditioning) breaker is off - ie., winter.

The jacuzzi's 240v/20amp GFI breaker kept tripping , even with no load (tub unplugged). The electrician inspected the breaker and it had burns - ie., it arc'ed. He installed a non-GFI 240v/20amp (for testing purposes) and the continuity, polarity and voltage at the tub was correct.
Neither the conduit or neutral showed voltage. The jacuzzi ran fine (nobody in it, of course) so we can eliminate it being a problem with the tub's circuitry.

I have two suspicions:

1) The GFI breaker was installed incorrectly. The end of pigtail on the GFI breaker did not appear to be crimped when the electrician took it out. I
could be wrong, however. Also, I looked the neutral wire and the wire's end
appears to be crimped toward the of the GFI.neutral-bus bar. This tells me the
electrician (perhaps) wired the neutral to the bus instead

What are the implications of incorrectly wiring a GFI breaker's neutral incorrectly? Will that arc the breaker - or must there still be some kind of a short situation?
GROUNED WIRE IS PROPER TERM. VERRY IMPRESSED YOU KNEW WHAT A BUS BAR WAS.
2) They cut a wire during pulling. That is why I asked about the conduit load requirements. The only problem with this theory is that the non-GFI breaker did Not trip during testing. If the wire was cut, it seems the test breaker would have also arc'ed -- GFI or not.

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Wire is THHN. MOST PEOPLE DONT KNOW TO LOOK ON THE ISALATION FOR THIS. WITHOUT GUIDANCE!
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Quote:
Originally Posted by Stubbie
I wanted to add that you were not clear where the 240 gfci was located. Was it in the jacuzzi or the service panel? I am assuming at the service panel which would support what i just said in the previous post, plus you mentioned you paid 200 dollars for it, so that is impling to me you installed it at the service panel.

Per the jacuzzi manual, two (2) dedicated circuits are required to be fully operational.

(1) Dedicated 240VAC, 20AMP

The 240v/20amp is a GFI breaker which, is at the panel of course. The receptacle for this circuit is a 20amp double pole, with the neutral wired
to the receptacles green/grounding screw.

(2) Dedicated 120VAC, 20AMP
The 120v/20amp is a GFCI receptacle -- which is at the tub. The breaker
is a standard 20amp (ie., $5 bucks).

You are one inpressive and knowledgeable D.I.Y. I hope every thing works out for you with this problem. Stubbie did you really move to illinois if so Iam proud to have you in my state. Love dropping in on your classes.
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Old 03-26-2008, 08:59 AM   #36
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Thanks for the atta-boy, Brad. I'm the one in the tub, not the electrician -- so that's pretty good motivation for me to learn a little bit about this stuff.
It is, otherwise, very interesting and yes-I'm pretty handy around the house.

I do live near Chicago - which, as you say, explains the conduit requirement.
I was surprised to hear about "Romex" while reading through electrical books.
Never heard of it before. I'll bet folks sure think twice about driving screws
into the wall -- unlike here.
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Old 03-26-2008, 09:14 AM   #37
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Quote:
Originally Posted by capndave View Post
Thanks for the atta-boy, Brad. I'm the one in the tub, not the electrician -- so that's pretty good motivation for me to learn a little bit about this stuff.
It is, otherwise, very interesting and yes-I'm pretty handy around the house.

I do live near Chicago - which, as you say, explains the conduit requirement.
I was surprised to hear about "Romex" while reading through electrical books.
Never heard of it before. I'll bet folks sure think twice about driving screws into the wall -- unlike here.
Well, most folks don't even know that there are wires behind that drywall. It's surprising the number of people that think that electricity is magical and just "appears" at the receptacle.

Personally, I have NEVER driven a nail or screw into a wire behind sheetrock. But, it is obviously an issue in places to warrant the "no romex" like Chicago.
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Old 03-26-2008, 03:16 PM   #38
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Quote:
Personally, I have NEVER driven a nail or screw into a wire behind sheetrock. But, it is obviously an issue in places to warrant the "no romex" like Chicago.
That likely isn't why they have pipe in Chicago but one feels better thinking that way.

Believe me if you were a drywaller by profession you wouldn't be able to say NEVER....

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