Sub Panel Load Thoughts?

[boilermanc]

Hi all, I plan to have the electric company and an electrician come out but thought I would get some feedback here. We have recently moved into a new (older) house that has a three car garage I am setting up shop in. I run lot's of stuff. Lincoln 225 welder requiring a 50amp breaker, Rand compressor on a 30 amp breaker, oven for powder coating another 30amp fuse. Plus I have a mig welder and table saw, miter saw, router, sander etc... Some florescent lights will need to go on the sub as well. Will be adding a dust collector to the mix.

Of course I dont run all this at one time. I might have the oven and the compressor running at the same time though. Along with lights. I have at least two 20 amp breaker from the main panel that feed out there so might just keep all the lights on those. I can run the saws on those as well.

I complicated this today by bringing a hot tub home that really needs to run off the sub that would be in the garage as it will be put on the deck that is off the garage. That adds a dedicated 50amp breaker to the sub.

The run to the main is at least 100' but all inside.

I plan to put in a 60 amp breaker that would run to the sub. I have 6.2 cable to run out there.

I'm thinking the 60amp can handle all of that but just seeing what you guys think. Like I said, I will call out the local boys but other opinions are appreciated.

thanks!

 

[ForceFed70]

I think you would be OK with a 60A panel if you mostly work alone in there.

If it were me, I'd probably go with a 100A just to be sure.

 

[JoeFin]

The run to the main is at least 100' but all inside.

I plan to put in a 60 amp breaker that would run to the sub. I have 6.2 cable to run out there.

I think your a bit light on the wire size

 

[theoldwizard1]

The run to the main is at least 100' but all inside.

I plan to put in a 60 amp breaker that would run to the sub. I have 6.2 cable to run out there.

If you are using copper and feed it from a 60A breaker on your main you can use 8/3 w/ground NM-B.

I'm thinking the 60amp can handle all of that but just seeing what you guys think. Like I said, I will call out the local boys but other opinions are appreciated.

If you are willing to "manage your loads" (no hot tub while welding) you should be okay.

Remember, it is the size of the breaker at the main that protects the whole sub, NOT the "main" breaker in the sub. Go with a 100A sub so you have enough slots for everything you are planning. This will give you at least 20 spaces for breakers.

 

[Norcal]

With 6/2 cable you can have either 120 or 240 volts not both. A 3 conductor + ground cable is required for the desired 120/240V.

 

[pattenp]

??? #8 NM-b is 40 amps.

If you are using copper and feed it from a 60A breaker on your main you can use 8/3 w/ground NM-B.
..........

 

[theoldwizard1]

??? #8 NM-b is 40 amps.

I retract my recommendation ! I guess the "calculator" I was looking at is not suitable NM-B.

I found another chart, specifically for NM-B. It says max current #6 NM-B at 140°F is 55A. I have read that code will allow you to "round up" to the next size breaker if none are available. (Square D does not make a 55A breaker.)

 

[wyliesdiesels]

Hi all, I plan to have the electric company and an electrician come out but thought I would get some feedback here. We have recently moved into a new (older) house that has a three car garage I am setting up shop in. I run lot's of stuff. Lincoln 225 welder requiring a 50amp breaker, Rand compressor on a 30 amp breaker, oven for powder coating another 30amp fuse. Plus I have a mig welder and table saw, miter saw, router, sander etc... Some florescent lights will need to go on the sub as well. Will be adding a dust collector to the mix.

Of course I dont run all this at one time. I might have the oven and the compressor running at the same time though. Along with lights. I have at least two 20 amp breaker from the main panel that feed out there so might just keep all the lights on those. I can run the saws on those as well.

I complicated this today by bringing a hot tub home that really needs to run off the sub that would be in the garage as it will be put on the deck that is off the garage. That adds a dedicated 50amp breaker to the sub.

The run to the main is at least 100' but all inside.

I plan to put in a 60 amp breaker that would run to the sub. I have 6.2 cable to run out there.

I'm thinking the 60amp can handle all of that but just seeing what you guys think. Like I said, I will call out the local boys but other opinions are appreciated.

thanks!

I would do a 100a feed. And 6/2 NM is the wrong cable. First u need to figure out the amperage u want, then u need to calculate voltage drop to figure out the suze of wire u need!

I retract my recommendation ! I goes the "calculator" I was looking at is not suitable NM-B.

I found another chart, specifically for NM-B. It says max current #6 NM-B at 140°F is 55A. I have read that code will allow you to "round up" to the next size breaker if none are available. (Square D does not make a 55A breaker.)

Why not just print yourself a copy of NEC 2011 310.15(b)(16)??

http://www.barr-thorp.com/wp-content/uploads/2011/04/Digest-176-NEC-Tables.pdf

And yes you are allowed to upsize the breaker if the ampacity doesnt match a standard breaker or fuse size as long as the calculated load doesnt go over the ampacity of the wire!!

 

[zmaxmotorsports]

How big of a service are you feeding the sub panel from?

 

[boilermanc]

Hey guys, sorry, updating this as I think I am getting close. A couple of updates:

1. I have 6.3 wire not 6.2 which should be fine. This runs up from the main box to the garage through the attic. I picked up some conduit from the local Ace that was changing ownership for half off, yeah!

2. Its a 200amp service coming into the house.

3. I found this box that I think should work. I like that it has the cutoff. The garage is in the house, down the stairs, to a hallway to main breaker. I am not too excited about being in the garage, having an issue and not being able to shut it off. Also, I want to separate it from the rest of the house and not have to turn everything off if there is a problem. Does this box have the right bar's?

http://www.homedepot.com/p/Eaton-100-Amp-20-Space-Circuit-BR-Type-Main-Breaker-Loadcenter-Value-Pack-Includes-6-Breakers-BR2020B100V/100168474#specifications

I also found this posting. I think he did a great job of outlining how to make this happen.

http://forum.grasscity.com/do-yourself/748307-diy-220240-60a-subpanel.html

 

[pattenp]

Since the sub-panel needs to have the neutrals isolated from the box a bonding strap or screw needs to be removed from the installed bar so it's not grounded to the box. A new ground bar will need to be added.

This... http://www.homedepot.com/p/Eaton-14-Terminal-Ground-Bar-Kit-GBK1420CS/100199885?N=5yc1vZbm0j

 

[boilermanc]

Since the sub-panel needs to have the neutrals isolated from the box a bonding strap or screw needs to be removed from the installed bar so it's not grounded to the box. A new ground bar will need to be added.

This... http://www.homedepot.com/p/Eaton-14-Terminal-Ground-Bar-Kit-GBK1420CS/100199885?N=5yc1vZbm0j

Excellent! Thanks!

 

[sberry]

Run another wire for the tub. I would want it from the main if possible and not connected to other equipment from a sub.

 

[Aceman]

I wouldn't touch this job without doing a load calc first.

If you are willing to "manage your loads" (no hot tub while welding) you should be okay.

This is a poor diy'er method at best and not the right way to do it.

 

[Charles (in GA)]

tin-plated aluminum buss bar according to the description. Get a copper or tin plated copper bus bar (correct spelling of bus is bus, not Buss, that is a trademarked name.)

Charles

 

[unsinkable]

I hope no one takes this the wrong way...I realize that we are all here to learn things, I have learned alot on this site.

That being said, I don't think anyone with little to no understanding of ampacity, proper use of the code, and things like voltage drop and PROPERLY grounded systems should be wiring services (subpanels) and jesus christ especially HOT TUBS !
Hire a licensed, qualified electrician. There are certain safety factors that must be adhered to before you climb into a vat of hot water with electricity connected to it. This is not the project to "hope the guy on the internet" was correct.
I try to help everyone, but every man must know his limitations.

"The safety book is written in blood"

 

[zmaxmotorsports]

I would do a 100a feed. And 6/2 NM is the wrong cable. First u need to figure out the amperage u want, then u need to calculate voltage drop to figure out the suze of wire u need!



Why not just print yourself a copy of NEC 2011 310.15(b)(16)??

http://www.barr-thorp.com/wp-content/uploads/2011/04/Digest-176-NEC-Tables.pdf

And yes you are allowed to upsize the breaker if the ampacity doesnt match a standard breaker or fuse size as long as the calculated load doesnt go over the ampacity of the wire!!

Id do the 100a sub also,but don't see any info on existing service size to house.

 

[sberry]

I hope no one takes this the wrong way...I realize that we are all here to learn things, I have learned alot on this site.

That being said, I don't think anyone with little to no understanding of ampacity, proper use of the code, and things like voltage drop and PROPERLY grounded systems should be wiring services (subpanels) and jesus christ especially HOT TUBS !
Hire a licensed, qualified electrician. There are certain safety factors that must be adhered to before you climb into a vat of hot water with electricity connected to it. This is not the project to "hope the guy on the internet" was correct.
I try to help everyone, but every man must know his limitations.

"The safety book is written in blood"

I am all for DIY but I tend to agree here. Its one reason I suggest a separate wire back to service main for a tub. As a side note was in a HD a while back and customer and the help were discussing some kind of tub setup. I didn't give my 2 cents but the help was a plumma I believe and neither was sure about what voltage it was running at etc.
I got friends that moved a tub, I didn't get a chance to look at the wire install but its a diy deal, they scare me.

 

[unsinkable]

It can get pretty scary out there.
I was in a HD one time and overheard a customer asking an orange apron which wire nuts to use...The apron replied "you don't need wire nuts, just use tape".
I told the customer that fire extinguishers were 3 aisles down.

I sometimes don't want to get involved, but I don't want someone to burn their house down either. As a licensed electrician you have to be careful, if you tell someone how to do something and they fark it up, the lawyers will inevitably be looking to blame someone.
and Boilerman, congrats on your new home, and good luck with your shop !

 

[toplessHO]

a good friend has a plate on his truck that reads
WIRING IS NO HOBBY
HIRE A QUALIFIED ELECTRICIAN

 

[D45]

I'm thinking the 60amp can handle all of that but just seeing what you guys think.

My house has 200amp service

I have a 60amp breaker in this panel feeding into a 100amp (rated) subpanel in my shop (1,000 sq feet)

The subpanel has 6 slots for breakers

Here's what I'm working with

Looks like I have four breakers used in the panel.......... and another two available to be used?

There are two breakers marked "20" and two breakers marked "15"

This wall used to be the exterior wall, thus the reason for the meter being mounted there. The shop was added on and attached to the side of the attached main garage and runs 65' down the side of the house

The house's main 200amp panel is located directly behind the subpanel, inside the attached original garage

 

[boilermanc]

Thanks for all the information guys. You have impressed on the safety concerns and I understand. I will be plotting out my course of action and will keep everyone informed on how things go!

thanks!

 

[sberry]

Home Depot has some good people but not everyone you ask in the store knows everything. Many know some but havnt had the study in particular areas of code and they really don't want them quoting it.
You notice it in a lot of questions relating to sub type panel installation and when is a main needed etc as well as some grounding. My local lumber yard is the same way.

 

[wyliesdiesels]

My house has 200amp service

I have a 60amp breaker in this panel feeding into a 100amp (rated) subpanel in my shop (1,000 sq feet)

The subpanel has 6 slots for breakers

Here's what I'm working with

Looks like I have four breakers used in the panel.......... and another two available to be used?

There are two breakers marked "20" and two breakers marked "15"

This wall used to be the exterior wall, thus the reason for the meter being mounted there. The shop was added on and attached to the side of the attached main garage and runs 65' down the side of the house

The house's main 200amp panel is located directly behind the subpanel, inside the attached original garage

Interesting note: that panel is labeled for corner grounded b phase service! Those are no longer allowed as new service in most areas

 

[D45]

School me..........what does Corner Grounded Phase B Service mean?

I believe the garage addition is about 10 years old

 

[wyliesdiesels]

In response to your earlier question, yes u have 2 spaces left. If u ever change out the panel and if this is in a detached structure, u will need a main disconnect if u hae more than 6 breaker handles...

School me..........what does Corner Grounded Phase B Service mean?

I believe the garage addition is about 10 years old

I forgot that SQ D equipment is labeled/listed for corner grounded Delta service.

Anyhow, corner grounded Delta service aka grounded B phase(though the grounded phase leg can be any of the leg, dependent on how the lineman or electrician hooked up the service or panel) was popular decades ago.

It is a 3-wire 3-phase service 240v line to line AND line to ground.

The grounded phase is to be wired LIKE a neutral- white or gray insulation, no fuses or OCPD in line with the grounded conductor, unless the OCPD simultaneously disconnects ALL phases at the same time.

BUT it is NOT a neutral- it isnt connected to the star point or center point on the transformer windings and u dont have 120v phase to neutral.

Breakers MUST be straight rated- 240v or 480v NOT slash rated 120v/240v or 480v/277v...this is because of the higher phase to ground voltage.

One reason corner grounded Delta service was used was to provide a grounded service on an existing ungrounded service without having to change much.

Corner grounded Delta service is harder on equipment and has different AIC ratings etc.

Im sure im missing something but thats the basics...

 

[D45]

So is what I have good or bad?

I am going to do some re-wiring this winter in the shop, and add more breakers to the subpanel

This is an attached structure

The shop is the addition on the left:

 

[justsam]

D45,
I suspect you may have a few compliance issues in regard to the exposed romex that is not protected, and I suspect that box with the GFI in it may have some box fill issues.

I am sure all works fine but you may have issues at time of sale.

 

[D45]

Yeah that is why I want to redo the wiring this winter

It all passed inspection when I bought the house last year

But, I also know there is some issues that I personally don't care for that will be addressed

 

[D45]

I think its stupid to have a GFI outlet anywhere in a garage

The far majority of the garage was done and built right

However, the wiring seems to e very novice

 

[Norcal]

I think its stupid to have a GFI outlet anywhere in a garage

The far majority of the garage was done and built right

However, the wiring seems to e very novice

You may think it's stupid, but GFCI's are required by code & they work well.

 

[D45]

Not code here, only if within certain feet of a water source

Not needed in my garage

 

[wyliesdiesels]

So is what I have good or bad?

What u have is fine. Your breakers are slash rated... I was just pointing out something that most wouldnt notice!

D45,
I suspect you may have a few compliance issues in regard to the exposed romex that is not protected, and I suspect that box with the GFI in it may have some box fill issues.

I am sure all works fine but you may have issues at time of sale.

Surface mounted NM/Romex is fine as long as its not subject to damage.

Not code here, only if within certain feet of a water source

Not needed in my garage

Where are u located and what code cycle are u on?

GFCIs have been required in garages for a while in the NEC so unless your AHJ is still on an old code cycle or has some local amendments, then it is required.

 

[Norcal]

What u have is fine. Your breakers are slash rated... I was just pointing out something that most wouldnt notice!



Surface mounted NM/Romex is fine as long as its not subject to damage.



Where are u located and what code cycle are u on?

GFCIs have been required in garages for a while in the NEC so unless your AHJ is still on an old code cycle or has some local amendments, then it is required.

It has been required since the 1978 NEC, it even predates the kitchen GFCI requirements.

 

[D45]

Code or not, my two garages passed inspection without them (just have one GFI)

When I redo all the wiring, the one GFI that I have will be tossed in the garbage

 

[wyliesdiesels]

Regardless that it passed inspection, its not to code. Inspectors miss things all the time!

 

[Norcal]

Code or not, my two garages passed inspection without them (just have one GFI)

When I redo all the wiring, the one GFI that I have will be tossed in the garbage

That is one of the most ignorant statements that have read here in a long time.

 

[CoopVA]

Regardless that it passed inspection, its not to code. Inspectors miss things all the time!

Probaly was just one of those home buyer inspections that aren't worth a ****...


Sent from my iPad using Tapatalk

 

[C96]

Code or not, my two garages passed inspection without them (just have one GFI)

When I redo all the wiring, the one GFI that I have will be tossed in the garbage

Lol…Make sure everything to the right of the meter gets the demo treatment, looks like garbage.

You’ve got what appears to be a 50a plug just dangling from exposed romex.

There are 4 NM cables one of which is at least a #6 and 2 EMT conduits along with a GFCI receptacle all crammed inside an undersized outlet box (I’m surprised there haven’t been some short circuits going on in there).

The sub-panel main feed should not pass through a receptacle box like that, but instead be more of a direct route. Also, exposed romex in a shop environment is asking for trouble.

Everything here to the right of the meter looks like an after thought and installed very poorly.

So, when you throw-out the gfci receptacle go ahead and demo the rest and also get yourself a nicer panel to work with, something with more space options would be nice so you don’t have to use tandem breakers. The 6/12 you have will get used up rather quickly. Bumping it up to 100 amps will also be a nice up-grade.

By the way, very nice looking place you have there, might as well fix the electrical to go with it.

Don’t forget the NEW GFCI breakers!!

 

[C96]

Oh, I forgot to mention, nice job on hijacking the thread too!