Shop power estimate

[mark mcfarlane]

Anyone care to review my 'max simultaneous power' requirements? Am I missing anything? Do these numbers look reasonable?

I am wondering if I can run both the shop and my 2800 sq ft house (in Houston, AC land) on the current 200AMP feed, or if I need to pay the significant fee to bring in a new feed, and maybe a new transformer....

Shop - Max simultaneous power usage	Qty	HP	Note	Amps (running)	Circuit
CU300	1	4.8 HP (230V)	30 amp curcuit, probably only uses 20 amps	30	230V	http://www.scmgroupna.com/en/products/classical-machines.c884/universal-combined-machines.887/cu-300-classic.721
DC40 Stock Feeder	1	0.5 HP		3	230V	http://www.cantekamerica.com/machinery/feeders/dc30-3-roll-variable-speed-power-feeder-2883.html
Dust Gorila Pro	1	5.0 HP (maybe 3HP)	30 amp curcuit, probably only uses 20 amps	20	230V	https://www.oneida-air.com/inventoryD.asp?item_no=XGK050105H&CatId={7F6C8978-92E8-4902-9A37-D8A254EDF4FC}
Shop Lights	30	32 watts	960 watts	8
Radio, mini-fridge				3
AC (mini-split) Shop		9000 BTU / 30.5 SEER		12	230V	http://www.mitsubishielectric.ca/en/...nit_Spec05.pdf
Studio Lights				3
AC (mini-split Studio)				12	230V
Total Simultaneous Amps				91

[John Sayen]

I think you should convert all line items to watts and then compare your total watts with your total panel watts capacity.

Will help avoid void any confusion with 110 vs 220 with regard to amp capacity.

[jack duren]

Why are you asking a woodworking hobby forum to instruct you on electrical issues?

[John Sayen]

Why are you asking a woodworking hobby forum to instruct you on electrical issues?

I'm not the OP but I imagine because this forum's description is as follows?

Building Electrical, Construction, Shop Layout and Dust Collection: Everything you want to know about housing all those tools!

[jack duren]

Even a certified electrician on the forum won't guarantee your house from catching on fire.

He should be asking the correct people in his area...

[Leo Graywacz]

What are you worried about? The worst that can happen is you trip a breaker (as long as everything is compliant). Adding things up looks like a peak of 168 amps total. Most of your machines when not under load draw substantially less. Lights, resistance heat and compressors draw continuous high currents.

[jack duren]

Should he add to his 200amp or pay to run a separate power to another building. He needs to check with local authorities on this...

[mark mcfarlane]

Why are you asking a woodworking hobby forum to instruct you on electrical issues?

Jack, I am consulting with my job electrician on this also. He used to teach the NEC code for 10 about years. Seems knowledgable to me.

From this forum I was more concerned about making certain I have identified what the max simultaneous load will be for the shop part of the build, so the chart above is what I call the worst case scenario: jointer running with DC and stock feeder on, all lights on,...

I guess I could add a 2HP compressor recycling in the 'worst case'.

Thanks for chiming in.

Cheers,

[John Lanciani]

Should he add to his 200amp or pay to run a separate power to another building. He needs to check with local authorities on this...

Why are you so worried about it? Lots of talent and knowledge here...

[jack duren]

I'm not worried about it. But have seen it too many times run into 40 replies with conflicting answers especially from NON qualified people who read a lot and think their qualified

So lets see if a certified electrician can answer this without a bunch of static for once.

[jack duren]

Jack, I am consulting with my job electrician on this also. He used to teach the NEC code for 10 about years. Seems knowledgable to me.

From this forum I was more concerned about making certain I have identified what the max simultaneous load will be for the shop part of the build, so the chart above is what I call the worst case scenario: jointer running with DC and stock feeder on, all lights on,...

I guess I could add a 2HP compressor recycling in the 'worst case'.

Thanks for chiming in.

Cheers,

I understand your trying to get info on your needs Mark. I just hope an answer can come without confusing the original question.

On a one man shop it's hard to overcome a 100 amp service. I have 95 amp service off my main into the garage. I can't pull enough by myself to pop the breaker..

The fact that it's a separate building concerned me on insurance with fire....

[Ole Anderson]

I am not a licensed electrician, but I did stay at a Holiday Inn Express about a month ago, so here goes: To answer your question, I believe you have it covered as you admit you might be 10 amps high on the CU300 (whatever that is) and that would be on one leg, the other leg will be less as some loads are 115 volts. However to be safe I would add in the compressor as you never know when it will decide to kick in.

I have the 2 hp Dust Gorilla and it draws 10 amps with the largest gate open, so you might be a bit low on assuming 20 amps for the 5 hp version.

As far as running it off your existing 200 amp panel, I wouldn't, not on a 2800 sf house in hot Texas. I would ask the electrician to run a second feed off the meter to your shop panel (if allowed by local code and your utility). I have seen that done frequently on 50 amp 240 volt spas. Check with the utility to make sure their secondary feed is adequate. You imply from your post that it is not. I wouldn't assume that when picking your options.

What are you looking at as far as your shop panel? If you go off before your house panel, it wouldn't be a sub-panel.

[Jim Andrew]

I have a 2 ton ac, a 3hp dc, multiple 4 bulb fluorescent fixtures, and a whole shop of woodworking machines I run on a 100 amp service with no problems.

[Art Mann]

Double post.

[Art Mann]

Panels are not rated in watts. They are rated in amps at 240 VAC and there is a good reason. Even if the total theoretical watt capacity of the panel isn't exceeded, the current capacity of one leg could still be exceeded. You have to pay attention to balance as well as wattage capacity. It is the current on the most heavily loaded leg that defines the required panel current capacity. For example, if one leg requires 5 A and the other leg requires 60A then the wiring and panel must be sized for 60A @ 240 VAC. That is just the way it works.

I think you should convert all line items to watts and then compare your total watts with your total panel watts capacity.

Will help avoid void any confusion with 110 vs 220 with regard to amp capacity.