Will I overload the circuit in my garage?

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Flyover

Trying not to screw things up worse
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If I'm reading the box right, my garage seems to be on its own circuit, but it only has two outlets.

One of the outlets has a 6-outlet power strip plugged into one of the sockets, and plugged into that is a very un-fancy treadmill (this one), an LED shop light, and a small fan or heater (depending on the season, to make running on the treadmill more comfortable). Sometimes a paper shredder or an injet printer will also be plugged into the power strip but will likely not be operated at the same time as the treadmill.

The other outlet has the garage door opener plugged into one socket, and into the other socket is another 6-outlet power strip with a long cord. Plugged into that power strip is another LED shop light and then a circular saw, a router, a table saw, a drill, or a shop vac -- usually only one of these plugged in at a time and almost certainly only one running at a time, not counting the shop light.

The garage door will typically not be operated while any of the equipment is being operated.

Do you think this circuit is overloaded? What would be the easiest/cheapest way to improve this setup for safety/reliability?
 
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This is a typical duplex recepticle; http://www.cooperindustries.com/con...ral_duty/standard_duplex_receptacles_270.html

They are available in both 15amp and 20amp configurations. Their longevity will depend upon the use, in current drawn by the equipment connected.

A garage should typically have "A" or multiple 20amp circuits, and in todays code, be GFCI protected.

What is the size of the or both breakers controlling this/these receptacles?
 
First, is this a detached or attached garage; this will let us be able to advise you if this garage can have multiple circuits running to it from the breaker panel.

Second, you mention two receptacles (outlets) presently being in the garage. Are these two on the same circuit or separate circuits?

Third, are the two receptacles (outlets) in the garage sharing any other receptacles elsewhere? Example: if the garage is attached the circuit could go from the panel to an receptacle/s in the home first then extend to the garage.

If the garage is attached to the house you can run multiple circuits to the garage if needed/wanted. If it is detached from the house then only one circuit may be run to the garage. If you presently have a 15 or 20 amp circuit going to the garage and want to increase the ability of the power in the garage you would need to run a larger feeder cable to the garage from the panel in the house and then install a sub-panel in the garage. This would give you greater ability.

If these two outlets (receptacles) in the garage are on the same circuit you just need to watch what you have plugged in at the same time as in what is "running" at the same time. If this is one circuit; let's say a 20amp circuit you need to be mindful of what the power/amp draw is on the devices you plan on running at the same time. It is not a matter of what is in the garage as in power saws, heaters (plug in), table saws, power drills etc that matters it is what you run at the same time that matters.

A simple Ohms Law calculation can be done to determine what you can run without possibly tripping the breaker.

20amp circuit x 120Volts gives you about 2,400 watts available before tripping the breaker.

15amp circuit x 120 volts gives you about 1,800 watts available before tripping the breaker.

If you have a device that is rated at 6amps (such as a drill) and you plug in a heater that pulls 13 amps and you only have a 15 amp circuit you will trip the breaker. So it depends what you use at the same time.

If you are unsure what your tools draw in amps calculate it.

If you have a plug in heater that is rated at 120v and 11 amps you take 120 x 11 and you get 1,320 watts. If the device only lists watts and you know it is a 120volt device then you take the listed watts for example: 950 and divide it by 120v and you get 7.916amps.

The other thing to keep in mind is that many of the power tools such as power saws etc need a bit more amp ability when you first start them up until they get to full running speed.

Your set up is fine so far as you have not given us any idea if you want to expand your ability to use more tools at one time. If you limit what you "run" at the same time you should be fine with the present setup. If you plan on running more power hungry tools at once then you may have to consider adding more circuits (if attached garage) or installing a larger feeder circuit with sub-panel if a detached garage (again can only have one circuit feeding it).

Disclaimer: If I missed something that one of the other members picks up on please excuse me as I just woke up and only on my first cup of java.
 
If you only use one device at a time then you will be fine.
You could have a 100 things plugged in but if you only turn one on, there will not be a problem.
 
Hi everyone, I'll try and answer Qs and comments in order.

- I don't know the size of the receptacles; the one in the back wall has the "test" and "reset" buttons in case that's a clue. The house was built in 79 in case that's another clue.
- This is an attached garage.
- Not sure if the receptacles are on the same circuit but I'll check later.
- The receptacle on the back wall is not shared with anything else so far as I know. The one in the ceiling is, I think, shared with one in the attic above the garage, into which is plugged a single LED light bulb that is basically never on.

If I was going to do something like run more circuits, I would just hire an electrician. I could probably look up how to do it on Youtube and save money but I know I just won't have the time. And I don't have the money to hire an electrician to do something like that at the moment anyway.

Like I said, aside from LED shop lights and the small fan/heater, I don't anticipate running more than one of any power tool or other piece of equipment at once.
 
The recep. with the test/reset buttons is a GFCI.

We can guide you in the upgrade, if you choose.
 
Adding more outlets is not science and it will not take long to know if you overload the circuit and what can be run at the same time.
If it is a detached garage you can not just run more circuits. You would likely have to replace the wire with something bigger and have a panel in the garage.
 
Adding more outlets is not science and it will not take long to know if you overload the circuit and what can be run at the same time.
If it is a detached garage you can not just run more circuits. You would likely have to replace the wire with something bigger and have a panel in the garage.

See the 4th statement of post #5.
 

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