Splicing into a 240 Volt Circuit...?

[PatrickW]

I've got a single 240 volt circuit in my garage that's hooked up to an electric heater.

The circuit runs through conduit on the inside of the garage. I'd like to "tap into" it and install a socket (like for an oven) so that I can plug in a 240 volt air compressor.

That should be easy - but here's the kicker: this circuit comes in through an "interuptible off peak meter". The kind that the power company can shut off during times of peak electrical usage.

Are there any "gotcha's" that I should watch out for?

I think this is ok to do, but I almost feel like I'm stealing cable TV or something. Will the power company be able to detect that I've done this? Will they even care? Should I even be concerned? I wouldn't run the heator or the compressor very often.

What do you guys think?

Thanks.

- PatrickW

 

[HoosierBuddy]

They might care.

If this is one of those "heat storage" heaters (or whatever they call them) that heats up during offpeak times and then gives you radiant heat AND is set up on a reduced power rate....my guess is that you'd be violating their tariff by tapping in to it.

Can they tell?

Depends. Around here, some power meters (in fact ALL of the REMC's meters) are equipped with communications that "talk" to the power company through the power lines (Turtle Communication? Or something like that). If so, they will be able to tell that something isn't Kosher if they bother to look.

The best thing to do would be to call the power company and just ask. Make sure you write down the name of whomever you talk to. That way if they say it's OK and then try to gig you later, you can say...but Candy said it was OK!

Good Luck!

Phil

 

[PatrickW]

It's an ordinary 10Kw electric garage heater on a 60 amp circuit.

But the power that runs through it is billed at a reduced rate. It's a separate meter from everything else.

Air compressor calls for 30 amps, so I think it would take less power than the heater does.

If I installed a switch so that I can only use the heater OR the compressor - never both at the same time - maybe that would be ok?

I suppose I could call the electric company, but I can't help but to think that sometimes it's better to ask for forgiveness than to ask for permission.

-PatrickW

 

[Tscott]

Well, If its billed at a reduced rate, then its only supposed to be used for heating would be my guess. Will they be able to tell? Probably not right away. I work for an electric coop in florida and you would be suprised by what people get away with. But eventually they may notice the extra power consumption but they may just think you are heating the garage more.

If they have a seperate rate for this meter, then it must be that they only want the heat to run during off peak times and therfore by allowing this you are given a lower rate as an incentive to allow them to shut your heat down when they want to. So it would be a violation to use the power for something else. Not sure of the penalties, but I knwo here it can be a felany if you steal power in large enough quantities but that is only in extreme cases.

I would say you should probably just have another circuit put in from your main panel but that is just my .02

Tom

 

[VvvJRvvV]

You can not tap into that line and run your compressor. First of all, it is on a 60 amp breaker. If you are running your compressor off of this line, you will not be fused properly. Is there no way to put a smaller service out into the garage?

It scares the hell out of me everytime I see "hometime" electricians wiring things up. My advise, ask a licensed electrician in your area to look at what you want to do. Get an estimate. Electric is not something you should try to cut corners on. It will burn you every time.

 

[sharpshooter]

My dryer and my 220 air conditioner are on the same breaker, I cant run them both at the same time but I can run them. That would be the same principle (wouldnt it???)

 

[thefairlaneman]

running them both at the same tme does not mean its 100% safe.The wire may not be large enough to carry that much load.

 

[Vermaraj]

My dryer and my 220 air conditioner are on the same breaker, I cant run them both at the same time but I can run them. That would be the same principle (wouldnt it???)

Air conditioner is usually 50 or 100 amps depending on the size, it could be more or less. A 220v dryer is usually 20 or 30 amps. lets take 20 &50.

If you have a short in the dryer its going to pull until it snaps the 50amp breaker. Since the plug wire and the internal components of the dryer are designed to be protected at a much lower current you will likely destroy any electronic component and the motor. Or things could heat up enough to start a fire.



As for the original question, I would check with the utility. Interruptible service is cheaper due to the flexibility it allows the utility company. If your in an area with high grid utilization they would probably welcome you adding large loads to this service. In fact they may offer incentives, including wiring a subpanel. The caveat is your compressor may not be available at peak hours: 7am - 6pm on heavy air conditioning days.

 

[PatrickW]

If your in an area with high grid utilization they would probably welcome you adding large loads to this service. In fact they may offer incentives, including wiring a subpanel. The caveat is your compressor may not be available at peak hours: 7am - 6pm on heavy air conditioning days.

Yes, they did give me a $100 rebate for putting in the interuptible meter.

It makes sense that they'd prefer to be able to control usage rather than not control usage.

Maybe I'm just being too cautions here. It's probably just fine to splice into this circuit and hook up an air compressor.

Thanks,

- PatrickW

 

[Charles (in GA)]

Yes, they did give me a $100 rebate for putting in the interuptible meter.

It makes sense that they'd prefer to be able to control usage rather than not control usage.

Maybe I'm just being too cautions here. It's probably just fine to splice into this circuit and hook up an air compressor.

Thanks,

- PatrickW

I'm sure you signed something when this meter was installed. It probably specified what you can an cannot do with this circuit and you need to consult this contract before doing anything.

Charles

 

[VvvJRvvV]

Yes, they did give me a $100 rebate for putting in the interuptible meter.

It makes sense that they'd prefer to be able to control usage rather than not control usage.

Maybe I'm just being too cautions here. It's probably just fine to splice into this circuit and hook up an air compressor.

Thanks,

- PatrickW

It is not "just fine" to splice into the circuit. It has been explained above, more than once...

In the end, it is your house/garage.

 

[Bill K]

How is the rest of the garage powered? Is there a subpanel in the garage that feed all the other outlets? If so that is where you need to pull power from, provided there is room in the panel for another circuit. Stay away from the other circuit for all the reasons above.
My thoughts.
Bill

 

[Ign]

Because a compressor is an auto-start device it really should have a dedicated circuit anyhow.

As for putting a compressor that only draws 30A on a 50A or 60A circuit, it's not ideal but it's not a huge deal provided the wire is sized correctly. Somewhere in your house you're probably running a single 100W light bulb on a 15A circuit, same principle as far as I'm concerned altho someone will disagree w me.

Likewise all the 220 receptacles in my shop are 50A 'cause the plasma needs it. I run my Hobart 210 on these receptacles as well, but the Hobart doesn't need a 50A circuit. My compressor is on a dedicated 30A circuit. One of the main reasons for running the smallest circuit possible is simply cost - lower amperage equals smaller wire which equals less copper and we all know copper ain't cheap.

Regardless, since you already have this one circuit in conduit in your garage, it shouldn't be a problem to run another circuit. You could very well pull it thru the existing conduit, depending upon the size of the conduit and the size of wire you wish/need to run. I'd personally hate to not have my compressor during peak hours.

 

[Vermaraj]

A light bulb is a piece of resistive wire packaged in a vacuum. By definition it can only pull a fixed amount of current which is dependent on the voltage present. This type of circuit has nothing in common with an air conditioner or air compressor which are inductive loads. Inductive load can pull current until something breaks.

Bottom line is there is a right way and a wrong way to do things. Circuits are sized and protected to safeguard the user and the structure. The cost and effort to do something the right way will seem trivial if the price of education is a trip to the hospital or a burned down house or worse.

 

[Ign]

A light bulb is a piece of resistive wire packaged in a vacuum. By definition it can only pull a fixed amount of current which is dependent on the voltage present. This type of circuit has nothing in common with an air conditioner or air compressor which are inductive loads. Inductive load can pull current until something breaks.

Is not a hand drill an inductive load? Or a Kitchenaid mixer? So if I run my 3/8" drill on a 15A circuit is this unsafe? I don't think so. If I run a mixer on the kitchen counter on a 20A circuit am I asking for fire? By your reasoning one would need a myriad of circuits in 1A increments to run any given motor.

My pancake compressor will run on a 15A circuit, is it thus unsafe on a 20A?

I'm NOT saying one should throw caution to the wind here. I guess what I'm saying is each peson is cautious to varying degrees. In any discussion such as this you will find people who are extremely cautious, and those who are a bit more lax. Ultimately the homeowner will have to do what he is comfortable with.

 

[Vermaraj]

Hand drills, kitchen mixers, etc are household appliances. They have to be designed by the manufacturer to be plugged into a 20 amp outlet. They also have to be designed for all sorts of predictable abuse like; dragging the appliance across the counter by the plug, dropping the appliance on the floor, dripping water, etc....

I can wire a 25hp 480v/3phase motor to a welding plug and run it from any 50 amp welding outlet. Is this safe? It all depends on what you have wired between the plug and the motor. Which is why 240v plugs have different pin configurations depending on the current rating.

 

[VvvJRvvV]

I'm NOT saying one should throw caution to the wind here. I guess what I'm saying is each peson is cautious to varying degrees. In any discussion such as this you will find people who are extremely cautious, and those who are a bit more lax. Ultimately the homeowner will have to do what he is comfortable with.

It's not about being cautious. There is an electrical code that is put out, for the safety of people. Most people have some respect for this code. What he wants to do is against code, period.

As for you putting all 50A 220v receptacles in your garage, that is up to you. However, if something were to go wrong, you would probably end up smoking your Hobart before you blow the breaker.

As I said before, it's your house/garage. I sleep well at night knowing my house is wired properly. Do you?

One of the main reasons for running the smallest circuit possible is simply cost - lower amperage equals smaller wire which equals less copper and we all know copper ain't cheap.

I am sorry to inform you but you are incorrect. The reason for running the correct (not smallest) circuit size is for protection. The purpose is so that you blow a circuit breaker instead of blowing up precious tools / compressors / welders, ect...

You are correct in saying that copper is not cheap. Up until a year ago, I could buy 12-2 NMB for around $100/1000 ft. This year it peaked to almost $400/1000 ft. Currently it is around $300/1000 ft.

It is obvious you are not an electrician, you are one of the people I worry about having to bring the big red truck to see.

 

[JOHN1]

Rule of Thumb

Never "splice" into a 220v circuit.

Each 220v circuit should have only one 220v draw, period.

Should a "splice" or multiple draw circuit fail and cause a fire I bet you will have an insurance issue, not to mention damage or life threatening issue.

It just is not worth it. I am not an electrician but a welder/machinist.

Material is al ot cheaper than the above.

Any electricins out there agree/disagree?

John S.

 

[PatrickW]

Thanks everyone for the comments and advice!

I decided not to do it.

I don't know enough about electricity and probably would have created more problems than it was worth.

Instead, I bought a smaller air compressor that plugs into 110 volt.

It still saves me money, because I can plug it into a long extension cord that's already running to an outlet located on my neighbors house. The cord is already set up, as I'm using it to run my Christmas lights on my house.

It's unlikely that anyone will notice the cord - it's brown, and there are dead leaves everywhere. In a short time there will be snow on top of that, so I'm golden.

- PatrickW