# somebody real smart did this



## HARRY304E (Sep 15, 2010)

Teaspoon said:


> Went on a service call yesterday, Carpenter friend of mine called said he was on a job doing some remodel work. Home owner had an old outbuilding that he needed the Electric cut loose from.So i go to jobsite.I pull the cover on the200 amp disconnect box.there is a 10-2 wire double lugged to the main lugs of the disconnect. on the other end the#10 wire was wired into a100amp main breaker of the sub panel. Some people have no clue.


I wonder what the connected load in the sub panel is?


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## Dammonn (Mar 12, 2012)

The connected load does not matter, the wire is protected by a 100 amp breaker. The wire would melt before it ever hit the trip.


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## mrmike (Dec 10, 2010)

Dammonn said:


> The connected load does not matter, the wire is protected by a 100 amp breaker. The wire would melt before it ever hit the trip.


In Respect, the connected load does matter, as the wire never melted, so we know that it was at or below the wire's capacity...................


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## Southeast Power (Jan 18, 2009)

HARRY304E said:


> I wonder what the connected load in the sub panel is?


1- 60 watt lamp, 1-Bug Zapper, 1- beer fridge.:thumbsup:


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## Teaspoon (Jan 10, 2009)

HARRY304E said:


> I wonder what the connected load in the sub panel is?


Looked like there had been a few lights & Receptacles. The building was empty when I got there. It is to be torn down.


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## McClary’s Electrical (Feb 21, 2009)

Teaspoon said:


> Went on a service call yesterday, Carpenter friend of mine called said he was on a job doing some remodel work. Home owner had an old outbuilding that he needed the Electric cut loose from.So i go to jobsite.I pull the cover on the200 amp disconnect box.there is a 10-2 wire double lugged to the main lugs of the disconnect. on the other end the#10 wire was wired into a100amp main breaker of the sub panel. Some people have no clue.


Outside tap rule...


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## JDJ (Aug 9, 2011)

Friend is moving shop asked me to help clean up new locations electrical. FP panel which I love. I'll have to take a pic of the #12 bugged behind "B" phase on the line side of the main that feeds to a single breaker enclosure for the exit lights. Good times.


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## Awg-Dawg (Jan 23, 2007)

JDJ said:


> Friend is moving shop asked me to help clean up new locations electrical. FP panel which I love. I'll have to take a pic of the #12 bugged behind "B" phase on the line side of the main that feeds to a single breaker enclosure for the exit lights. Good times.


 I still see that from time to time.

Usually, 2pole fusible discos tho.


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## noarcflash (Sep 14, 2011)

JDJ said:


> Friend is moving shop asked me to help clean up new locations electrical. FP panel which I love. I'll have to take a pic of the #12 bugged behind "B" phase on the line side of the main that feeds to a single breaker enclosure for the exit lights. Good times.


 
Tap rule, perfectly legal if under 25', and done correctly.

I've seen hot taps into main buss bars.


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## JDJ (Aug 9, 2011)

noarcflash said:


> Tap rule, perfectly legal if under 25', and done correctly.
> 
> I've seen hot taps into main buss bars.



Thanks . Had forgotten about this.


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## 10492 (Jan 4, 2010)

How would this be a sub-panel?

If fed from the line side of the service disconnect, that would make that a main panel, no?


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## God man (Oct 15, 2010)

noarcflash said:


> Tap rule, perfectly legal if under 25', and done correctly.
> 
> I've seen hot taps into main buss bars.


I never grasped the tap rules. Can someone expound on them snd learn me sometin!


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## macmikeman (Jan 23, 2007)

God man said:


> I never grasped the tap rules. Can someone expound on them snd learn me sometin!


Those are the rules that allow you to tap and drop the wire size to below what the breaker will open at, but if you try using a smaller wire than a generator overcurrent protective device, you will go to hell for it........


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## BBQ (Nov 16, 2010)

macmikeman said:


> but if you try using a smaller wire than a generator overcurrent protective device, you will go to hell for it........


Consider an outdoor genset with a 100 amp breaker, but you only need 60 amps.

You could run 6 AWG from that 100 amp breaker to a 60 amp breaker or fuse at the house using the outside tap rules.


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## Ontariojer (May 19, 2011)

Dammonn said:


> The connected load does not matter, the wire is protected by a 100 amp breaker. The wire would melt before it ever hit the trip.


#10 melt at 100amps? I HIGHLY doubt that. I have seen 14 running 60amps. It was warm to the touch(that's how i accidentally discovered it!), but nowhere near melting.


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## frenchelectrican (Mar 15, 2007)

Ontariojer said:


> #10 melt at 100amps? I HIGHLY doubt that. I have seen 14 running 60amps. It was warm to the touch(that's how i accidentally discovered it!), but nowhere near melting.


Check this youtube link and this may will change your mind on this one the youtube the person say it was on 20 amp circuit so it will be 4.0mm2 ( #12 awg ) and it ran 60 amp on that conductor so see it yourself.





 
Merci,
Marc


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## Ontariojer (May 19, 2011)

frenchelectrican said:


> Check this youtube link and this may will change your mind on this one the youtube the person say it was on 20 amp circuit so it will be 4.0mm2 ( #12 awg ) and it ran 60 amp on that conductor so see it yourself.
> 
> 
> 
> ...


Really? That video seemed a little suspect to me. If 60A did that to #12 there would be A LOT more house fires.

Is just under 1watt per inch enough to smoke that wire? Because thats the heating of #12 wire, two conductors, at 60 amps. I doubt it. Similarly, #10 2 conductor would be 1.6watts/inch at 100amps.

Someone please check my math :thumbup:


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## BBQ (Nov 16, 2010)

Lets qualify things a bit.

12 Copper will not melt with 60 amps of current.

The insulation may smoke, but the copper will be fine.

I think 14 AWG copper becomes a fuse somewhere around 200 amps in free air.

So exactly what are we saying will happen?


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## Ontariojer (May 19, 2011)

I am saying the following.

I have personally seen a 14/2 with the following loads. 6x500w halogen worklight heads, a 12" chop saw, A wet tile saw, a skilsaw and a fridge. All going at once.(obviously the saws and fridge were intermittant, but going pretty frequently, all day). The wire was tight against(but not surrounded by) fiberglass insulation. It was summer, and it was hot.

The wire was definitely warm to the touch, but not hot.

FPE 15a brkr, in case you were wondering.

Just sayin.


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