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Subpanel

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aalleexx

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Need advise from the group. Built a small(4x8) lean-to shed about 6 inches from my shop wall. I want to put a 100 amp sub panel in it to feed a 7.5hp air compressor and one 20 amp circuit. What is the best way to run the feed from the shop panel? In the picture, the blue marks are where the panel is and the red/pink box is where I want to exit the wall to go to the shed. There is a girt right above the red line that is not in view. Will just be running small exhuast fan and possibly one light besides the compressor.
 

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wyliesdiesels

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What is feeding the shop subpanel?Another panel in the shop or a panel in a different building?

If that is the only panel in the shop, there is a code violation since there are more than 6 handles and you are out of room regardless for more circuits

Even though its technically a separate building(the shed), i would just run your 2 circuits to it

But you will have to change out your current panel (the pictured one).

Other thing to consider is the size of the breaker and the ampacity of the wire feeding this panel

A 7.5HP motor is quite the load on startup for a small feeder. If the feeding breaker is only 50-60a and you have other stuff running, you may trip the breaker
 
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wyliesdiesels

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Looks like a 3-wire feed w/ bonded neutral but theres also a separate ground bar on the right?

When was this panel installed?

If recently, its a code violation as well

What does the stranded copper go to? Ground rod?
 
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PCustoms

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mm08822 said:
And could have posted this in his original thread about the same question.
Click to expand...

Sounded like he was going to be about 30 ft away in that thread, sub panel makes much more sense in that case.

I'm trying to figure out how you build a lean-to shed 6 in away from the wall of your building...
 
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aalleexx

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I never thought of that! I thought I might get some helpful suggestions to do it myself. If I wanted to call an electrician, I wouldn't have asked on here. I put that funky conduit in for a welding circuit across the shop. Wasn't looking for praise. It was my first attempt to do something like this.
 

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PCustoms

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aalleexx said:
I never thought of that! I thought I might get some helpful suggestions to do it myself. If I wanted to call an electrician, I wouldn't have asked on here. I put that funky conduit in for a welding circuit across the shop. Wasn't looking for praise. It was my first attempt to do something like this.
Click to expand...
I don't want to kick a guy when he's down but those rafters don't look like they're on the top plate well...


As for the panel, @wyliesdiesels raise some initial questions that are potential safety issues
 
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sparky 1971

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I suggest: figure out how much power you have feeding the panel right now and will it support a 7-1/2 horse compressor. If yes, get a larger panel and while installing it, fix all of the problems that have already been pointed out as well as putting a bushing on the feeder conduit. Then, get all of the shi...stuff out of the way and run a conduit to the desired location. It's probably best to call someone.

I don't remember the running load for a 7-1/2 HP compressor and I'm too lazy as well as too comfy in my recliner to look it up, but I do remember that the SQD cheat sheet suggests a 7-1/2 motor to be fed with #8 wire and an 80 amp breaker so take that info into consideration when sizing the new feeder.
 
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aalleexx

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wyliesdiesels said:
Looks like a 3-wire feed w/ bonded neutral but theres also a separate ground bar on the right?

When was this panel installed?

If recently, its a code violation as well

What does the stranded copper go to? Ground rod?
Click to expand...
Panel from 2010, added funky circuit to welder last year. Yes, copper to ground rod.
 
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aalleexx

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sparky 1971 said:
I suggest: figure out how much power you have feeding the panel right now and will it support a 7-1/2 horse compressor. If yes, get a larger panel and while installing it, fix all of the problems that have already been pointed out as well as putting a bushing on the feeder conduit. Then, get all of the shi...stuff out of the way and run a conduit to the desired location. It's probably best to call someone.

I don't remember the running load for a 7-1/2 HP compressor and I'm too lazy as well as too comfy in my recliner to look it up, but I do remember that the SQD cheat sheet suggests a 7-1/2 motor to be fed with #8 wire and an 80 amp breaker so take that info into consideration when sizing the new feeder.
Click to expand...
Compressor was coming off of a 40 amp breaker in the shop I got it from. Ran like that for 5 years. I think I have to have a panel in a detached shed. Will find out tomorrow.
 
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sparky 1971

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wyliesdiesels said:
Looks like a 3-wire feed w/ bonded neutral but theres also a separate ground bar on the right?

When was this panel installed?

If recently, its a code violation as well

What does the stranded copper go to? Ground rod?
Click to expand...
I don't see the bonding screw or strap but admit to not knowing diddly about CH panels, probably the least used in this part of the country.
 
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PCustoms

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aalleexx said:
Compressor was coming off of a 40 amp breaker in the shop I got it from. Ran like that for 5 years. I think I have to have a panel in a detached shed. Will find out tomorrow.
Click to expand...

Pic of compressor, ideally of the motor nameplate?

I would find a way to make that "shed" attached.
 
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sparky 1971

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aalleexx said:
Compressor was coming off of a 40 amp breaker in the shop I got it from. Ran like that for 5 years.
Click to expand...
Ya made me get up and look. According to my cheater, FLC of a 7-1/2 HP single phase is 40 amps. Are you sure of the HP? I would think that start up current would at least occasionally cause tripping.
aalleexx said:
I think I have to have a panel in a detached shed. Will find out tomorrow.
Click to expand...
Make sure it's either a main breaker or can be converted to one.

And now that I am looking at it on my desktop and am wearing glasses, I can see that there are three spaces left. It looked like there was only one left when on my tablet. You still need a main or a disconnect, but don't need more spaces.
 
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wyliesdiesels

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sparky 1971 said:
Ya made me get up and look. According to my cheater, FLC of a 7-1/2 HP single phase is 40 amps. Are you sure of the HP? I would think that start up current would at least occasionally cause tripping.
Click to expand...

yes its 40a so need 50a rated wire (40x1.25). max beaker can be 100a

will need a disco in the shed and of course it will need to be hardwired
 
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aalleexx

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Would something like this one, going to a 60 amp disconnect, then to magnetic starter, work?
 

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mm08822

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If you are going to replace the panel in the shop, then make it worth your time. Get more spaces for future.

Might as well make it CH also so cb's interchange between them.

Also, you could re-use the existing CH panel for the lean to and it would serve as the local disconnect.
 
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wyliesdiesels

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sparky 1971 said:
Make sure it's either a main breaker or can be converted to one.

And now that I am looking at it on my desktop and am wearing glasses, I can see that there are three spaces left. It looked like there was only one left when on my tablet. You still need a main or a disconnect, but don't need more spaces.
Click to expand...

only way to add a main is a backfed one which would take 2 of those spaces. could do a disco on the feeder but thats arguably more work than just swapping out the panel.
 
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Norcal

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The CH panel was the highest quality load center available at the time Eaton cheapened them since then but they are still a desirable panel & has a copper bus unlike SQ D Homeline.
 
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Chuckster in NJ

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aalleexx said:
I never thought of that! I thought I might get some helpful suggestions to do it myself. If I wanted to call an electrician, I wouldn't have asked on here. I put that funky conduit in for a welding circuit across the shop. Wasn't looking for praise. It was my first attempt to do something like this.
Click to expand...
So an experienced electrician who worked hard for years and took the time to get an education is supposed to tell you how to fix this mess for free over the internet without seeing the entire job in person is dangerous………. NOT to mention the local licensed electrical contractor who pays his license fee, insurance, tools and has a family to feed is the safest way to go.


What I am trying to say here is: Stop "fing around" and HIRE A LICENSED ELECTRICAL CONTRACTOR.
 
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aalleexx

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Chuckster in NJ said:
So an experienced electrician who worked hard for years and took the time to get an education is supposed to tell you how to fix this mess for free over the internet without seeing the entire job in person is dangerous………. NOT to mention the local licensed electrical contractor who pays his license fee, insurance, tools and has a family to feed is the safest way to go.


What I am trying to say here is: Stop "fing around" and HIRE A LICENSED ELECTRICAL CONTRACTOR.
Click to expand...
Not F'ing around. Said I would have electrician look it over and see if I need to make any changes. I will pay him for his work. If it bothers you so much, move on.
 
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sparky 1971

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wyliesdiesels said:
only way to add a main is a backfed one which would take 2 of those spaces. could do a disco on the feeder but thats arguably more work than just swapping out the panel.
Click to expand...
I know that, it just didn't come out right. I meant main breaker panel or disconnect; and I had already mentioned that he needed a larger panel based on available spaces but that was when I thought there was only one hole left. He's probably thinking he can use slots 14 and 16 for the shed.
 
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