Whether to Add a Panel or Run Separate Circuits

[BentBierz]

Hello,

I have a detached 1500 sq. ft. building that I am converting one side to a wood shop. There is a 100 amp panel coming from the main that is on the opposite side of the building from where I am going to set up the shop. The panel is very lightly loaded and has more than enough space to run my 240V shop equipment that includes:

- Sliding Table Saw (30 amp)
- Band Saw (30 amp)
- Drill Press (15 amp)
- Lathe (20 amp)
- Dust Collector (30 amp)
- Air Compressor (unk...not certain yet what I want/need)
- Misc. other circuits for miter saw, powered hand tools, etc.

* Amps are required circuit breaker sizes, not the typical equipment load.

Unless someone else is working with me in the shop at the same time (very rarely), I will never have more than two pieces of equipment running at a time, one of those being a dust collector.

I have several different options I am considering:

1. Run separate circuits off of existing panel for each piece of equipment.
2. Drop a 100 amp breaker in the existing panel and run to a new 100 amp panel on the wood shop side of the building (approx. 60' of wire run).

Option 1: I guess the primary advantage of this option is that I have the available circuit space, with some to spare, so wouldn't have to buy a new panel or more costly heavy gauge wire but will have to run more smaller gauge wire and conduit.

Option 2: Advantage of this option is theoretically less conduit/wire to run to get to each dedicated circuit.

BTW...I have two steel buildings and will not run Romex in either. It is probably the German overkill in me but I like conduit as it protects the wiring better. We live on acreage out in the country and get the occasional rodent in our buildings that like to chew on things.

I would appreciate thoughts from those that have done this in the past. Thanks.

 

[wyliesdiesels]

running a branch feeder to a subpanel will save you money in materials and time.

 

[sberry]

Also improves voltage drop, also makes it easy to add as you go and provides local disconnect to circuits.

 

[sberry]

I ran one for a customer recently, put another panel across the building. I have 5 panels in my own building in addition to the main in my own building.

 

[BentBierz]

running a branch feeder to a subpanel will save you money in materials and time.

Also improves voltage drop, also makes it easy to add as you go and provides local disconnect to circuits.

I ran one for a customer recently, put another panel across the building. I have 5 panels in my own building in addition to the main in my own building.

Thanks for the replies. A separate panel is the way I have been leaning but wanted a sanity check.

BTW...my existing panel in my building has two hots, neutral and a ground with the neutral and ground separated in the panel. It also is hooked to two grounding rods. Will I need to do the same thing for any additional panels?

 

[Norcal]

Thanks for the replies. A separate panel is the way I have been leaning but wanted a sanity check.

BTW...my existing panel in my building has two hots, neutral and a ground with the neutral and ground separated in the panel. It also is hooked to two grounding rods. Will I need to do the same thing for any additional panels?

Do not need rods for additional panels in the same bldg., but a 4-wire feeder is still required for the subpanel. I recommend you do not cheap out on the number of spaces in the new panel, 16-24 spaces will be very good to have in the future.

 

[BentBierz]

Do not need rods for additional panels in the same bldg., but a 4-wire feeder is still required for the subpanel. I recommend you do not cheap out on the number of spaces in the new panel, 16-24 spaces will be very good to have in the future.

Thanks Norcal...solid advice!

 

[theoldwizard1]

... shop equipment that includes:

- Sliding Table Saw (30 amp)
- Band Saw (30 amp)
- Drill Press (15 amp)
- Lathe (20 amp)
- Dust Collector (30 amp)

Go back and check the labels on that equipment ! Those number seem AWFULLY high unless they are commercial machines and those all operate on 240V ! 30A @ 240V is at least a 3 hp motor.

 

[sberry]

Not all of them require 30A run but are allowed on 30 circuits or use them for start up overhead.

 

[BentBierz]

Go back and check the labels on that equipment ! Those number seem AWFULLY high unless they are commercial machines and those all operate on 240V ! 30A @ 240V is at least a 3 hp motor.

With the exception of the drill press, all of the machinery is commercial/extreme hobbiest. I am retired Coast Guard (currently work as a CG civilian) and my son is CG active duty with 16 years service. We are working on a small start-up business (I am a very decent wood worker with some disposable income as I move toward retirement-retirement. My son is an excellent woodworker with much more talent but less money. Trying to set up a shop for both of us in retirement (he will most likely have to have a day job after retiring from active duty). But, to reiterate, it is all heavy duty equipment e.g. sliding table saw has a 7.5 hp main motor and a 1 hp scoring saw motor...bandsaw 5 hp...etc.

 

[BentBierz]

Go back and check the labels on that equipment ! Those number seem AWFULLY high unless they are commercial machines and those all operate on 240V ! 30A @ 240V is at least a 3 hp motor.

Sorry...should just leave the comment alone but I listed 5 pieces of equipment with the breaker requirements. Typically, when I see this amount of detail in a post I assume the poster might have a “bit” of a clue in what they are talking about...at a minimum, they most likely pulled these numbers from somewhere other than their ****. When I see a post that says “I have a band saw, table saw, drill press and this really cool bar sign in my shop, can I run this on a 15 amp breaker in Kansas” then maybe I question-the-question.

 

[wyliesdiesels]

Sorry...should just leave the comment alone but I listed 5 pieces of equipment with the breaker requirements. Typically, when I see this amount of detail in a post I assume the poster might have a “bit” of a clue in what they are talking about...at a minimum, they most likely pulled these numbers from somewhere other than their ****. When I see a post that says “I have a band saw, table saw, drill press and this really cool bar sign in my shop, can I run this on a 15 amp breaker in Kansas” then maybe I question-the-question.

Except that breaker sizes are NOT whats used for doing load calcs and sizing services.

If breaker sizes WERE used, some residential services would need to be 600a or more...

This may be what the wizard was alluding to....

 

[sberry]

Due to the nature of these forums the wiz has a valid question for a couple reasons, don't get too hurt. The true demand isn't the breaker size and many,,, maybe most questions of this nature about how much really over estimate the demand.

 

[AntonLargiader]

Not sure what the big deal is here. He was very clear in his [seemingly unedited] first post about these being breaker sizes, and what he was likely to use at once. I didn't see him asking for a load calc based on those numbers. He asked about going the subpanel route, and got (and welcomed) good advice.

 

[MattT]

But, to reiterate, it is all heavy duty equipment e.g. sliding table saw has a 7.5 hp main motor and a 1 hp scoring saw motor...bandsaw 5 hp...etc.

You might want to check the FLA and breaker requirements for those machines.

 

[BentBierz]

Except that breaker sizes are NOT whats used for doing load calcs and sizing services.

If breaker sizes WERE used, some residential services would need to be 600a or more...

This may be what the wizard was alluding to....

Thanks for your comments but not certain how we got on load calcs. I mentioned what I was going to be putting on the panel and what breaker sizes were recommended for each of the pieces of equipment only as a discussion point for whether to keep it all on my existing panel or to put in a sub panel, not as a load calc discussion. Maybe I could have written the following in a more articulate way: " Amps are required circuit breaker sizes, not the typical equipment load."

 

[BentBierz]

For breaker sizes, I might have said "recommended" instead of "required."

 

[mike93lx]

Thanks for your comments but not certain how we got on load calcs. I mentioned what I was going to be putting on the panel and what breaker sizes were recommended for each of the pieces of equipment only as a discussion point for whether to keep it all on my existing panel or to put in a sub panel, not as a load calc discussion. Maybe I could have written the following in a more articulate way: " Amps are required circuit breaker sizes, not the typical equipment load."

You were very clear.

Some people just want to hear themselves talk.

Sounds like an awesome woodshop. If you are game, a thread on its setup would be mint

 

[BentBierz]

You were very clear.

Some people just want to hear themselves talk.

Sounds like an awesome woodshop. If you are game, a thread on its setup would be mint

Thanks! BTW...good idea about a shop thread...hadn't really thought about it but just might do it. I have been the worst at documenting any of the major projects we have done around our place. Months later I'll ask my wife..."Hey, did we get any pictures of that?" and the answer is typically "no" yet I almost always have my iPhone within easy reach.