Generator Conductors

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iwire

iwire

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Hypothetical.

I have a large generator, it has a 400 amp breaker on it.

I installed it about 75' behind my home and ran an underground raceway from the genset in through the foundation directly into the back of a 100 amp fused disconnect.

My calculated load is 95 amps total continuous and non-continuous.

I ran 3 AWG CU XHHW-2 from the 400 amp genset OCPD all the way to the 100 amp fused disconnect inside.

Do I pass inspection or get a red tag.

Remember red tags come with code sections attached. :cool:
 
without taking grounding into consideration, I see no problem so far
 
It seems okay to me assuming your gec to the ground rods exist. Do I win???:grin: Poor design with that load and the potential of the genset. Disco at genset-- gec's I presume. Disco at house and gec's

#3 good for 100 amps.

I am trying to get at the 75feet--- not within sight so I am guessing you think the disco should be outside at the house but I would say not.

BTW-- I never do generators so....:grin:
 
To be fair lets assume all the grounding and disconnect issues are code compliant. :smile:

The only thing to focus on are the size of the conductors from the generators OCPD to the OCPD I have in the house.
 
It might be a stretch to call this a "tap", but I based my answer on 240.21 (B) (5)
 
Tag,

240.4 Protection of Conductors.
Conductors, other than flexible cords, flexible cables, and fixture wires, shall be protected against overcurrent in accordance with their ampacities specified in 310.15, unless otherwise permitted or required in 240.4(A) through (G).

Where are generators mentioned in (A) - (G)
 
augie47 said:
It might be a stretch to call this a "tap", but I based my answer on 240.21 (B) (5)
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:smile: You got it, and I figured this would take awhile. :cool:

Per the definition of tap in 240.2 I do not feel it is a stretch at all.

If I moved the generator inside the house I could use 240.21(B)(1) or (2).

To use 240.21(B)(2) I would have to increase the 3 AWG up to 1/0 or so.
 
How about 445.13 Ampacity of conductors? What is the current rating on the nameplate? Should you have sized the conductors at 115%? Or is the 400 amp OCPD the rating on the gen?
 
The Iceman said:
How about 445.13 Ampacity of conductors? What is the current rating on the nameplate? Should you have sized the conductors at 115%? Or is the 400 amp OCPD the rating on the gen?
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That section applies to the conductors between the windings and the first overcurrent device. In this case the 400 OCPD mounted on the gen-set.
 
My brain was screaming TAP,240,TAP,240,TAP, But, I could not get over,"Why does he have a 96KW gen set feeding a house with a 100I service?" "96KW genset,ATS,he must be made of money!"
 
Karl H said:
"Why does he have a 96KW gen set feeding a house with a 100I service?"
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This is not a real situation, just an imaginary one overdone as an example.

It is a sidetrack to this thread

Generator Feeders

I did not want to Hijack Jerseydaze thread. :smile:

In real life I have a 100 amp service with a 5000 watt portable generator, I am not rolling in dough. :grin:
 
iwire said:
.........................In real life I have a 100 amp service with a 5000 watt portable generator, I am not rolling in dough. :grin:
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Do you have a transfer switch or (surely not) :)
 
augie47 said:
Do you have a transfer switch
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No, it is entirely portable, I bought it to run a sump pump that is cord and plug connected.

Someday I may get one of those interlock kits for my panel so I can pick and chose what I want to run.

The funny thing is I moved in the home about 8 years ago and have not needed the generator once for the house.
 
iwire said:
The funny thing is I moved in the home about 8 years ago and have not needed the generator once for the house.
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I hope you started it a few times since then.. it may never run again:grin:
 
After I got over how impractical this install was.While in a rush to get to 240 I ripped the page containing Table 310.17 in my code book. DOOH!!
Oh well I don't plan on FREE AIR ing anything in the future anyways. lol
 
Dennis Alwon said:
I hope you started it a few times since then.. it may never run again:grin:
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Your right but I have not in a bit, I keep saying I will. :roll:

I have brought it to work and used it during service changes, I had the thing running straight for like 26 hours on one change.
 
My denseness is overwhelming me. What part of 240.21(B)(5) does this not comply with??? #2 ?? please explain-I am missing something here.
 
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