NEED POWER!!!... help....

[65Stang]

Okay, so I am getting ready to run all the electrical for my garage (21' x 21'). I will be running all the wiring in the walls and bringing it all back to a panel that I will have yet to supply power to. But I am not sure if the main panel in my house can even support 50 amps for my garage.

My house has a 200 amp (or so it seems) panel indicated by the 200 amp main breaker. I have 400 amps worth of breakers in the panels, 200 amps on each side (see pics). I am getting the gut check feeling that I would need to change out my panel in order to supply 50 or 100 amps to the garage... but need to confirm. Also, I do have baseboard heat (GODD&%$%IT^%$^!#) in the house, so they do take up quite a bid of room in the main panel. Please let me know your thoughts....

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I should also note that my current shop, which is attached to my new garage (so awesome!!) currently has 20 amps running to it (I think). I have thrown the breaker quite a few times when running all lights, fan, radio, saw, fridge, and compressor kicks on. I use the shop mostly for wood working and house stuff, won't be doing too much heavy work in the garage, no table saws, skill saws, etc, but perhaps a lift eventually or intermediate use of a 120v mig welder.

 

[shamrock12]

Wow, alot of high load circuits you got there, but as small as the panel look, I'd image your monthly bills are shockin' high! This is the first time I have seen 200 amps main with only 20 spaces, seems ridiculous limited. Should have had at least 30 spaces at the minimum, 40 spaces ideally. I don't like tandem breakers because they are prone to break/fail easier than regular breakers. Not to mention that tandem cost more than two regular breakers. It does not seems like you have that much 120v circuits around the house either.

Anyway, you basically have two choices. One is to upgrade the main panel to 30 or 40 spaces. If I were you, I'd go with 40 spaces especially with all those electric heaters! Another choice is to add a subpanel next to it. Take two of existing 240V circuits out of main panel and re-route to the subpanel. Replace one of old space in main panel with 100amps breaker to feed the subpanel and another with 50 or 100amps for the garage. I wouldn't feed the garage from the subpanel because it would be limited.

 

[65Stang]

Thanks for the info, looks like I may have to have an electrician come out and change out the panels after I route the power from the garage to the main panel. I should also note that my house is only 1,400 square feet.

There's also only two circuits that have ever thrown a breaker, the one for the kitchen and the one for the old/existing shop.

 

[ddawg16]

Open up the panel and see what size wire you have coming in. If it's 0000 wire...then it can handle 300 amps....also check to see what the total amp rating on the panel is....

The experts should chime in...but I'm thinking that if you have the right wire coming in (300 amps)...put in a 300 amp main breaker....then you could install a 100a 220v breaker to feed your shop.

BTW....I would look into doing something about the breaker to the kitchen that is triping.....the garage I understand....but most fires start in the kitchen....I would look into off loading some of that load.

And don't forget....just because you have 400 amps worth of breakers, it doesn't mean your going to pull that much. I doubt you are going to load down every ckt in the house to it's max at the same time.

FWIW....I did a load check on my new panel when I installed it....picked an evening when normal things were hapening...tv on...lights...wife cooking dinner...and measured all the FLA's on the ckt's....plenty of breathing room....

 

[goodfellow]

I'd go for a small sub-panel -- That heating system must "eat you alive" in the colder months. I'd dread to see that electric bill.

 

[cw_racefan]

Far from and expert, but.......

It's not as simple as adding up breakers, or just adding a box with more spaces. You need to do (or have done) a demand load calculation to see what your incoming power requirements are. Then you can tell whether you need to upgrade your service or not. Upgrading service also is not as simple as just upping the main breaker. The panel needs to be rated for it, the incoming service (including meter head, and everything on the power company side) needs to be sized properly etc.

Best advice, get a licensed electrician to evaluate your situation and go from there.

 

[65Stang]

Getting an electrician on board will most likely have to happen, that I understand. I will be running a heavy duty cable to the garage from the box, but will need to have someone else take it from there.

My biggest drawback is the baseboard heaters. They run at around 8 to 15 amps each, which ***** up a lot of the usage in the main panel. I believe they could be added together. For example, in one location there is a an 10 amp heater and a 4 amp heater on one 20 amp breaker. Not the most efficient use of the power I would think. I definitely need to load test the panel...

 

[Charles (in GA)]

Electric heat is a continuous load according to the NEC, therefore, you cannot exceed 80% of a breakers rated capacity on the heater breakers. A 20 amp breaker cannot be loaded over 16 amps, thus your 10 amp and 4 amp heaters are all you will be able to put on that one breaker.

I had a house with baseboard heaters, it was extremely noisy, but you knew when one was heating up or cooling down. It may be possible to move circuits around to put more nearly the max allowed load on the heat breakers, freeing up space, but if you have the proper size incoming cable to provide for 200 amps (which I think you would if you have a 200 amp main) you probably should consider installing a 40 space breaker panel.

You could easily take this panel and move it to your garage/shop, as 20 spaces would be more than enough for that. I'm not a Square D fan, but since you have one, install a new 40 space Square D (NOT Homeline) and you will have common/interchangable breakers that way.

Charles

 

[65Stang]

Electric heat is a continuous load according to the NEC, therefore, you cannot exceed 80% of a breakers rated capacity on the heater breakers. A 20 amp breaker cannot be loaded over 16 amps, thus your 10 amp and 4 amp heaters are all you will be able to put on that one breaker.

I had a house with baseboard heaters, it was extremely noisy, but you knew when one was heating up or cooling down. It may be possible to move circuits around to put more nearly the max allowed load on the heat breakers, freeing up space, but if you have the proper size incoming cable to provide for 200 amps (which I think you would if you have a 200 amp main) you probably should consider installing a 40 space breaker panel.

You could easily take this panel and move it to your garage/shop, as 20 spaces would be more than enough for that. I'm not a Square D fan, but since you have one, install a new 40 space Square D (NOT Homeline) and you will have common/interchangable breakers that way.

Charles

If I have an incoming cable adequate for 200 amps, I put the existing 200 amp breaker in the garage, and put a 40 space 200 amp panel in place of the main, would I be overloaded? Or, would the 40 space panel just allow me to more efficiently utilize the power coming in and possibly send some to the garage?

 

[Aceman]

Since it looks like you'll be hiring an electrician, I'm not going to go into great detail. He'll be able to see exactly what you have and be able to make the best decision based on your needs and load requirements. Just a couple things worth mentioning. Changing your panel may be nice for the sake of more spaces but it is not an absolute necessity, if it's slash rated. If your not planning on adding any more circuits other than the feed to this new garage panel and your panel is slash rated(it'll say 20/40 on the inside cover, meaning 20 spaces available and up to 40 circuits) I would leave it. Space is nice but the cost to swap it out isn't worth it in my opinion even if you re-used this panel in your garage. Google "Square D quad breaker," this will allow you to free up some space by combining two of your 2 pole breakers. Again this is just my opinion. Your electrician will know what's best for you.

Open up the panel and see what size wire you have coming in. If it's 0000 wire...then it can handle 300 amps.

No.

The experts should chime in...but I'm thinking that if you have the right wire coming in (300 amps)...put in a 300 amp main breaker....then you could install a 100a 220v breaker to feed your shop.

When electricians install residential services they don't waste money by installing oversize wire just to limit it with a smaller breaker. If it has a 200 amp main breaker, there is a 99.9% chance that it's 200 amp wire feeding it.

 

[65Stang]

Since it looks like you'll be hiring an electrician, I'm not going to go into great detail. He'll be able to see exactly what you have and be able to make the best decision based on your needs and load requirements. Just a couple things worth mentioning. Changing your panel may be nice for the sake of more spaces but it is not an absolute necessity, if it's slash rated. If your not planning on adding any more circuits other than the feed to this new garage panel and your panel is slash rated(it'll say 20/40 on the inside cover, meaning 20 spaces available and up to 40 circuits) I would leave it. Space is nice but the cost to swap it out isn't worth it in my opinion even if you re-used this panel in your garage. Google "Square D quad breaker," this will allow you to free up some space by combining two of your 2 pole breakers. Again this is just my opinion. Your electrician will know what's best for you.QUOTE]


Would it then just make sense for me to get a panel for the garage, run cable from the garage to the main panel, and then let an electrician take it from there? Also, where would the cable from the garage connect within the main panel? Incoming cable? I have done quite a bit of wiring, but none of the panel work before and would prefer to stay away from it at this point. I am work in Construction, so I usually have a good basic understanding of things.

 

[Charles (in GA)]

If I have an incoming cable adequate for 200 amps, I put the existing 200 amp breaker in the garage, and put a 40 space 200 amp panel in place of the main, would I be overloaded? Or, would the 40 space panel just allow me to more efficiently utilize the power coming in and possibly send some to the garage?

Yes, you would install a double pole breaker, probably 100 amp, size the cable to the garage to match, and supply the garage panel. All power would come thru the main breaker in the house panel, so you could never overload it (for very long) as it would trip.

An electrician can hopefully tell you how much current you are using at one time, and how to best get more power to your garage. Just don't undersize the panel in the garage, such as a 6 or 8 place. Put in a "too big" of a panel, you will never regret it.

Charles

 

[65Stang]

Sounds good, I was planning on a 100 or 200 amp panel in the garage. I already have the cable for connecting the garage panel to the main, I believe I got "freakin' huge" guage cable, but I have it written down someplace.

 

[shamrock12]

I doubt you would need over 100amps for your garage unless you are planning on having compressor, welder, lift, electric heater and water, drill press, grinder, tons of lights etc. running all at once. For typical 120/240V panel the biggest "branch circuit" breaker you could install is usually 100amps. Anything bigger than that and you would need a main panel with pass-through lugs.