# All 220 volt outlets are the same, right?



## bunkie

My shop occupies the same space as the laundry. We have an electric dryer. When I bought my cabinet saw, I went to big box store and got a plug that fit the dryer outlet. Problem solved!

I had an electrician in the other day to quote on various jobs. I mentioned that I wanted a quote on getting a 220V circuit as I'd like to have the outlet in a more convenient spot. He took a look at my saw and said "this is a 20 amp saw and you are using a 30 amp circuit". The upshot is that the breaker is over-sized for use with the saw. In the greater scheme of things, the risk is probably pretty small. But it's not zero. I always unplug the saw when it's not in use, but it's conceivable that I could forget.

So, I guess that the new circuit has risen to the top of the list of things to be done. A few weeks ago, the house across the street burned down. It wasn't an electrical fire, but it surely focuses the mind on things that are best avoided.


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## Brrman

I just recently added a couple of 20A 220v outlets to my shop. A dryer outlet/plug is not really what you want for that. You want some 12/2 wire, a 20A double breaker and something like this:









and this


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## HorizontalMike

I used these plugs and outlets. They are locking and I find that assuring/safer. Oh yeah, I also used 10-3 armor clad from the box to the outlets PLUS changed out the 14-3 tool power cords to 12-3 power cords. If you want to call me anal, that should be Dr. Anal (PhD):


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## Bertha

That amperage discrepancy would make me nervous but I'm not a sparky. I use the exact system as Mike above. Before I installed the locking plugs, I once had an offcut unplug my saw. That really got my attention.


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## awsimons

What risk would there by running a 20 amp saw on a 30 amp circuit?

Alan


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## bunkie

Conceivably, you could have a situation where the saw was stalled and was drawing, say, 28 amps which would overload the internal wiring of the saw without tripping the breaker causing eventual failure of the insulation which could lead to a fire.

A (hopefully) simple solution would be to wire in a 20 amp breaker and mount it inside the saw.

But the right thing to do is to get a proper circuit wired.


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## Bertha

Again, not a sparky, but I would think that if the saw began to draw more than it's 20A rating, there would be no tripping of the circuit. There are alot of electricians here. Maybe I'll get educated.


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## brtech

Does the electrician want you to put 5A breakers on your outlet strings that now only have CFLs and laptops on them?

I think this is a very small problem. If you are really worried, sure, a new circuit with the right sized breaker is a fine solution. You can also have him install a sub panel, or even a simple fused disconnect between the dryer and the saw outlet. I'd just leave it. Or, even better - have him give you a couple of 110 outlets on the 220 circuit.

Horizontal Mike's connectors are "Twist Locks" and they are used when you frequently plug and unplug the connection. The ones Brrman uses are fine for a connection that is roughly never disconnected.

Now, you obviously never run the dryer when you run the saw, right? If that is even a remote possibility, then you want a separate circuit for the saw.


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## HorizontalMike

Been +35yr since my sparky days, but I would think you should make sure your wiring is capable of handling the 30amp load. The breaker is there to FIRST save the wiring in the walls and SECOND to save the tool. A more current sparky can give you the specifics on wire loads for each size of wiring and length of each run.

Along those lines I probably should swap out my 50amp breaker (running 10-3 240v) to something smaller that matches my 30amp tools. Originally put the 50amp breaker in because it served two tools (but I only USE one at a time! DOAH!).


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## RONFINCH

Drawing less amps then your breaker can handle isn't the problem. As Bunkie said, not tripping the breaker when drawing more than your machine is rated for is going to lead to burning up your equipment.


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## Bertha

I imagine the saw probably has its own 20A breaker at the motor. I hadn't considered that the breaker primarily insures the wiring, not the tool. See, I learned something.


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## bunkie

As I said, the risk is small. And, of course, any time you run a total load lower than the rated circuit breaker the same situation exists. For the record, he didn't suggest 5A breakers ;-)

Since I have only one outlet for the dryer, I unplug it before plugging in the saw. So there's no chance of popping the breaker while both ripping some oak and drying my shirts ;-)

I guess that my feeling is that accepting risks like this one is a slippery slope. I've been pretty lucky in my life with risks taken so far but I feel that, sooner or later, luck has a tendency to run out.


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## devann

I've seen several different ones. Depends on the amps. Ask TopamaxSurvivor I sure he can tell you what you need.


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## awsimons

This has come up before and I have been curious why people are worried about it. Breakers are meant to protect the wiring inside your walls from overheating and causing a fire. Breakers aren't meant to protect equipment.

Honestly, I think choosing to have an electrician come out, who could possibly mess up his work and use the improper wire/breaker size, which could have the potential of causing a house fire, is a GREATER risk than running a 20 amp motor on a 30 amp circuit.

Alan


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## Loren

Maybe you should get a second or third opinion from other
electricians. Guys who have their own wood and metal machinery
in their garages are probably gonna give you prudent advice.

And NO - not all 220 volt outlets are the same. You can wire your
220 with one type and your 110 with another and this prevents
you from plugging the wrong tool into the the wrong outlet.


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## HorizontalMike

Just as Alan has repeated part of what I mentioned earlier: Breakers protect house wiring FIRST and foremost, but an equally important point (and one I am also guilty of forgetting) is that *breakers CAN HELP protect equipment when properly sized to each machine.* Many/Most of our equipment has thermal overload protection built in (often in the magnetic switch). Beyond that, the key is to match as closely as possible the breaker with the machine amperage for an added layer of protection (or should I say preemptive damage control). The closer you get, the less you *may* damage your equipment if the built-in thermal protection fails. No guarantees here but you get the idea. Don't bring a flame thrower to a wiener roasting contest…


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## awsimons

Mike,
I agree with what you are saying. Breakers can definitely protect equipment if sized near the amperage of the equipment running on the circuit, but personally, I think it is riskier than just leaving the breakers alone.

Here's my ridiculous scenario: Someone has an enormous shop built with dedicated circuits for every single one of his tools. Some are 15 amp tools, some are 20 amps, and some need 30 amps. The circuits are sized perfectly for each tool, including appropriate wire gauges in the walls for the appropriate breaker size. Imagine, one day, this person decides he wants to rearrange his tools and "protect" his tools by switching the breakers to the appropriate size for each tool. Well, now we have a serious situation where wires in the walls could melt and cause a fire in fault conditions!

This is an extreme situation, but I think sometimes it can be dangerous to advise people who may not be savvy with electrical work to be this concerned with breaker sizes, when the risk-reduction is really not that great.

My opinion only.
Alan


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## themitrejoint

Brrman's outlets are 20amp, HorizontalMike's are 30amp. The breaker protects the "in the wall wiring". In your living-room you may have two or three wall outlets on a 15amp circuit. If you plug in a 10amp vacuum cleaner in one, no problem. If you plug in two 10amp appliances, the breaker will trip protecting the "in the wall" wiring, not the appliances. The only protection for the appliance is either you (witnessing an overload) or a built in appliance reset. Additionally, a direct short in an appliance will cause extreme heat drawing significant amperage far exceeding the rated amperage for that appliance (burning it up) and the circuit (tripping the breaker).

A direct short in your tool will definitely let the smoke out of the tool. You will either have to have the tool repaired (put the smoke back into the tool) or replace it.


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## Bertha

I hadn't considered either Frank's point above. It makes sense that a true short would draw far more than 30A and trip the breaker at the load center to protect the wall wiring. I had all the smoke put back into a drill once and it never quite worked the same


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## HorizontalMike

I ran ALL of my 240v on 10-3 armored cable surface mounted with longest run less than 20ft. My leftover 10-3 went for surface mounted 120v 4-gang outlets. I still have some 12-3 120v outlets, but over-kill is the word for power supply wiring. This way I can scale UP or DOWN in breaker size for equipment-dedicated outlets as needed/desired. But like Frank says, equipment protection is a crap shoot in that you MAY minimize some damage OR still fry it. I would rather at least try and match the amperage so that maybe I'll trip the breaker BEFORE actually burning up a motor or such. Again, no guarantees…


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## Bertha

I wish I had surface mounted. I'm already running into the dilemma mentioned above and I just had my power upgraded a few months ago. If I had it to do over, I'd copy HorizontalMike. I'm still considering copying his beard.


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## wilterbeast

Until 5 yrs ago i was a journyman electrician, running a 20 amp saw on a 30 amp circuit is not bad as long as the cord going to the saw can handle it. If you think about it in your house you probably have a lamp thats pluged into a 20 amp outlet? In ohio every kitchen requires 2 20 amp circuits in the kitchen regardless of what your using. Wirewhere you run into problems is in a situation like horizontal mike has where is breaker size is too big for the wire he has in the circuit, if he has a 50 breaker protecting 10 gauge wire ( 10 gauge wire is suitable for 30 amp) the 10 gauge wire can potentially have a continues load of of 45 amps and never trip the breaker, that would creat high heat and possible a fire. If something happen to your saw that your going to go over 20 amps your actually going to shoot way over 20 amps tripping the breaker anyway. Its also important to note that 99% of electrical fires are do to loose connections causeing the connection to ark


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## bunkie

I hooked my saw up as follows. I bought a dryer cord with a molded plug. I also bought a metal junction box, a metal cover for same and a pair of cord strain reliefs that fit the box. The saw came without a plug, so I ran the saw cord into the box, secured it with the strain relief, ran the bare wire end of the dryer cord into the other side of the bos, secured it and connected the wires with wire nuts. The cord is rated for 30 amps, so I should be okay. It's all nice and tight with the minimum amount of wire in the box and the ground wired to the box body.


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## Bertha

That's the exact the way I wired my saw but I paid an electrician big bucks to plug it into the wall!


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## wilterbeast

I would say your good to go then.


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## drewnahant

im not an electrician, but I have taken quite a few elecrical engineering courses, and physics courses covering electricity and magnetism, so rather than speak to what the code specifies, I speak to what the practical reality is, THERE IS NO DANGER FROM THIS! Just as stated above, you dont install 5A 110 circuits for your small appliances, because the breaker is to protect the overload of the wires in the walls, not the appliance. If the circuit was installed as a 30A, then I trust they wired it heavily enough to bear the 30A, in reality the wiring coded for 30 will bear about 45 before you are in any risk, the only danger is to your saw, and that is only as much danger as there is from plugging a blender into a 15A circuit when it only needs 6A. almost all motors for stationary power tools have a built in resetable breaker, and even if they dont have that, to be UL listed, they have to have an internal fuse, which is more likely located in the switch than the motor. I wouldnt waste your money downgrading a circuit that is, if anything, safer than a circuit designed to handle only 20A. As far as code goes you will have to see what the electricians say, but as far as im aware, code only applies to whats in the wall, what you plug into it is your business, that why you have to have breakers, so morons can try to plug a welder into a 15A outlet without damaging anything.


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## HorizontalMike

Well, I AM going to fix my own foul-up (I've got a spare 30 amp breaker sitting here). That's the problem with being out of the sparky business for +35yr. I remember enough to get myself into trouble on occasion.

Just went back and checked my machines (NO guesswork this time):
14" BS = 7 amps at 240v
G0690 TS = 20 amps at 240v
G0593 Jointer = 15 amps at 240v

R4330 Planer = 15 amps at 120v

And HEY! Guess where I currently have the 50 amp 240v breaker!? On the *7 amp* machine! DOAH! This gettin' old crap is surely over-rated… but it beats the alternative (at least that is what I hear).


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## biglarry

Mike

If you have a 50 amp breaker your 10-3 wire, it is nothing but a fuse. As Alan said the breakers are only their to protect the wiring to the outlet. You will need a 6 gauge wire connected to the 50 amp breaker. When it comes to wire size only the amperage count, the voltage doesn't matter if it 110 or 220.

bunkie

The only thing I would worry about is that you have no smaller than 10 gauge wire wire from the breaker to the outlet.


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## toddbeaulieu

Boy, everyone's got a different opinion about … EVERYTHING!

I'm no electrician, but I've researched this very topic, including calling the manufacturers.

I don't buy into the idea that a breaker is supposed to protect the device. Not at all!

I believe the breaker is there to provent a catastrophic failure, which includes overheating the wiring. If my saw were to short out, it's got internal overload protection. If that were to fail, the breaker would trip before disaster … which does not include damage to the saw. This seems to coincide with what biglarry is saying. And it does NOT agree with what an electrician wanted me to do.

I may be wrong … but at the end of the day, all I can do is read a million posts, with a million opinions, call a dozen manufacturers, talk to a few electricians and … decide what seems right for me.


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## HorizontalMike

biglarry,
Don't miss the DOAH! when I was talkin' about the 50amp breaker. I actually had this 50amp breaker when I first wired the garage (7yr ago) and it was hooked up to a 18" run of #6 for a "future" welder directly below the service box. I never bought that welder, BTW. Then last year, when I decided to set up the woodshop, I used it on a double run of 10-3 for 240v service, converting the "welder" outlet and adding another longer run.

This has been bugging me for a long time and when this thread came up that bug started itching in my ear to get off my duff and change it. Just checked and have a spare 2-pole 20amp 240v ready to go. I'll throw the main garage 100amp breaker in the house 200amp box and swap it out in the morning.

My point about bringing this up for like the third time on this thread is that we all get lazy, even when we know better.


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## Gregn

This has been an interesting thread and fits in with what I was thinking about. That was what to use for 240 volt receptacles in my new shop. I just finished wiring the shop tonight and put power to it. The only thing left to do is install the 240 volt outlets. The circuits are on 30 amp breakers with 10 gauge wire.


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## Grandpa

Well again I am not an electrician. I have taken the National Electric Code class at our local technical school and I am currently a home inspector. We are required to remove the dead panel on the front of your circuit breaker panel and check for proper wiring etc. You need a new electrician. The circuit breaker protects the wiring in the wall as many have stated. If the receptacle was opriginally wired with a 30A breaker and 10 gauge wore then it is correct and that is what a clothes dryer normally uses. Never wire a 110V receptacle on one leg of a 220V circuit as someone has recommended above. I think that is what I read. We all use a 7 amp router on a 20 amp circuit circuit daily. When we leave the receptacle we are using stranded wire so it should carry more amperage since on the surface of the wire carries amperage and strands have more surface. The one thing I did when I wired my shop is I used 20A receptacles on my 20A circuits. Home are usually wired with 15A receptacles on the 20A circuit. Another thing with the saw is the wiring is in the open air so it will be cooler. If it were in the wall with insulation around it there would be cause to worrry because it could heat up. How many are using GFCI in their garage shops? I do believe that the code currently requires a GFCI on 110V garage receptacles. If you want a way to disconnect the power to a tool I think an electricty disconnect would work fine. I see those often on central air conditioning units and electric water heaters. They are relatively cheap ($10 or so)and they are simply a mechaniical device designed for this purpose. Don't use a breaker for a switch. Not designed for that purpose.


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## TopamaxSurvivor

What is the hp and full load amps on the motor name plate?


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## HorizontalMike

Dang Topa, it's about time ya got here!

*;-)*


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## Bertha

^now for the final word on the subject.


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## TopamaxSurvivor

Are you guys overconfident? ;-))


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## TopamaxSurvivor

With all due respect to the opinons given, there is not enough information given to answer the question.


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## markT61

I side with those (were there any?) that think it better to be oversized.

Your tool motor ain't gonna burn up in an instant, some deliberate misuse required.

However plug a light into the same outlet, and operate the tool. Light dim ? when starting the tool. Low voltage can also hurt the motor, forcing it to draw more current.

Go oversize with any extensions, and wiring. Do you plug your 100 watt light (1 amp) or toothbrush (less) in a 15 am outlet ? Thought so.


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## runswithscissors

You don't need 3 wire cord for 220v. You do need two wires plus a ground (yes, I know that sounds like 3 wire, but it isn't the same). The dryer has 2 hots plus a neutral because the motor runs off 110, so it needs one of the hots plus the neutral.

I don't know why they're made that way, though. Even very small motors run normally on 220v. in places like Australia. And oddly, I never saw a 3 slot outlet in Australia. Everything has just 2 prongs/slots. I wonder how they ground stuff?


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## TopamaxSurvivor

> You don t need 3 wire cord for 220v. You do need two wires plus a ground (yes, I know that sounds like 3 wire, but it isn t the same). The dryer has 2 hots plus a neutral because the motor runs off 110, so it needs one of the hots plus the neutral.


That depends if you are buying romex, non-metallic sheathed cable, house wiring, where the ground does not count in nomenclature OR flexible cord, such as SO, in which all the conductors are counted in the nomenclature. I'd hate to see someone confused, buying the wrong cable. Some of this stuff gets in the $1/ft range really quick for larger machine wiring.



> I don t know why they re made that way, though. Even very small motors run normally on 220v. in places like Australia. And oddly, I never saw a 3 slot outlet in Australia. Everything has just 2 prongs/slots. I wonder how they ground stuff?
> - runswithscissors


I have never done any wiring in Australia ;-) but they are obviously running an ungrounded (by US definition) 220 volt single phase system. If it is ungrounded, most people will never get shocked as they are usually one leg to ground when they get it. When they do, it will be phase to phase and will hurt!!

We, here in the US, have little choice but to ground since we run 120/240 volts on our single phase systems. Without the ground, the voltage would float with the varying 120 volt loads. For instance, you have your WW plan on Sketchup and your computer is on in the shop. You fire up the table saw. They are on opposite sides of the center tap creating the 2 - 120 volt circuits. Without the ground to stabilize, the high current of the table saw series with the low current of the computer. Ohm's law causes the computer to see 190 volts + forcing all the smoke out! The table saw sees 30 or 40 volts. The motor probably doesn't even buzz before the computer goes opening the circuit. The table saw is OK, but we all know it is imperative to keep all the smoke in electrical equipment; therefore, the computer is history ;-(

I hope that helps to understand how the ground works in the US and why it isn't necessarily necessary in 220 single phase of other countries. (note: The European system probably has some sort of grounding, but it is substantially different than the US in basic household circuit operation.)


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## dhazelton

I would think if you had a 20 amp saw on a 20 amp circuit that every time the saw bogged down (which could be very often) you would trip the breaker. Thermal overload switch should protect the motor on a 30 amp circuit. BUT - I'm pretty sure code prohibits more than one 220 volt appliance per line.

When I had house wiring updated I had a couple of 20 amp kitchen circuits installed. One of the GFCI outlets crapped out recently and I went to replace it and found 14 gauge wire in the box that fed the next outlet -the idiot installed 12 gauge from panel to outlet one and then 14 gauge from there on. I switched out my breaker to 15 amps just to be on the safe side.


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## REO

Nice to see Topa laying in the practicality. Circuits in any voltage can be run with multiple outlets. Often it is desirable to match overload with a particular piece of equipment, hence fusible disconnects. I would suspect that none has replaced the wire in The light fixtures or the toaster with wire that is up to "code". The devise is not covered by the code so it does not have to comply. I do know a fellow that couldn't collect on insurance for fire damage because he had altered the manufactured state of a table saw by up sizeing the wire size and making it longer. Even though it complied with NEC code for wire size and voltage drop for length. A dryer and appliances like it have always run on two hots and a ground which is completely up to code. Using the ground for neutral when the 220 is split for 110 in the devise is why four wire connection is required. Two hots and a not (for neutral on 110 v internal circuits)for the electrical and the ground not used as a conductor for safety. although the saw may draw 20 amps at the rated HP it is not often that that level of power is required the saw with no load is running very close to synchronous. depending on the motor that would be 1800 or 3600 rpm. at rated HP they have "bogged down" to the nameplate 1725 or 3450 and draw the nameplate amperage. It is an interesting experiment check the draw of your saw while cutting different materials you will be surprised at what you find. You may also be surprised at how long you can run overloaded before the breaker trips!


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## Dal300

More on what *REO* and others have said, Your saw is rated for 20 amps which is normally the LRA, (Locked Rotor Amperage). I do believe that somewhere on that unit is a reset button. It really is just a circuit breaker and is the safety protection for the saw. If there is not one, you have an unsafe unit that is not acceptable to the majority of certifying agencies. In that case, your insurance won't pay off anyway.

Just for some information, you can go to your local RV dealer and buy what is called a "Dogbone". It splits a 50a 220v to two 110v plugs that have the neutrals disconnected. Just remember, the 220v in your hous is actually two legs of 110v on opposite phase. You cannot hook your dogbone up to two 110v that are on the same leg of the main breaker. You must plug into both sides of the box so you are using both of the incoming legs.


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## intelligen

As others have said, no, all 220V outlets are not the same-the different configurations have different meanings, so anyone who knows the standards can tell at a glance how the circuit is wired. The same goes for 110V outlets.

The main differences between 240V (aka 230V aka 220V) receptacles/plugs are the rated amperages and locking vs. non-locking, and the wiring configuration. Your dryer may plug into a NEMA 10 receptacle which is wired hot-hot-neutral, while your tools may plug into a more modern NEMA 6 receptacle which is wired hot-hot-ground. As long as the right wires are running to your receptacle, the hard part is done.

A common misconception about electrical devices is that a higher-amperage circuit will push the maximum number of amps to a device on the circuit. This is simply false-each device only draws what it needs (with the exception of power surges and lightning strikes).

From the panel to your tool, you never want to go from a lower amperage to a higher amperage, but it's safe to go from a higher amperage to a lower amperage. The reasoning is that it's safe to plug a lower-amperage device into a higher-amperage circuit because the device will only draw what it needs. Again, the circuit will not push more amps through the device simply because the circuit is capable of handling more.

For example, I have an L6-20R (locking NEMA-6 20A receptacle) installed in the ceiling of my garage, with a drop cord that had an L6-20P (locking NEMA-6 20A plug) on one end and a 6-15R (non-locking NEMA 6 15A receptacle) on the other end. The electrician originally installed the 6-15R because that's the type of plug on my table saw, but when I bought a planer I had to replace the 6-15R with a 6-20R because the planer requires 20A. (Note that 6-20R is compatible with both 6-20P and 6-15P plugs.) This was safe because the circuit itself is a 20A circuit, and the table saw will not suddenly draw more current (amps) just because the connector configuration changed (the circuit was capable of delivering 20A both before and after I changed the connector).

It would have been unsafe to replace the 20A plug on the planer with a 15A plug, because then someday someone might have plugged the planer into a 15A circuit, potentially either tripping the breaker or starting a fire. Similarly, it would be unsafe to replace my 5-20R with a 5-30R, because then someone might plug a 30A tool into my 20A circuit and potentially trip the breaker or start a fire.

As for comments about a 20A device drawing 28A for whatever reason, this generally should not happen, because that amperage is supposed to be the maximum current the device will draw during normal operation. Also keep in mind that a circuit breaker is a thermal device and it will not trip immediately when the amperage threshold is exceeded-it will allow the higher current to pass through for a short time until a temperature threshold his reached. A safety margin is built into most (maybe all?) devices-that is, many devices that draw more than 12A will spec a 20A circuit rather than a 15A circuit (I wouldn't be surprised if this is even be an electrical code requirement). I ran into a related issue recently when our commercial ice machine stopped working. I opened up the machine and found that the insulation on the power cord was melted, and the wire nuts had been completely melted off! Although the owner's manual clearly states that the ice machine draws 16A max and spec'd a 20A circuit, the previous owner had replaced the power cord and plug with 15A wiring, which predictably overheated and started melting things. We were fortunate that it didn't start a fire. In the future I'll always confirm that the wiring configuration is correct when I buy a large appliance or piece of machinery used.


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## WhyMe

> Nice to see Topa laying in the practicality. *Circuits in any voltage can be run with multiple outlets*.
> - REO


Depending on the building type of where the multi-outlet circuit is used there are limitations. International Residential Building Code E3702.5 limits the use of multi-outlet circuits to circuits of no more than 20 amps. The voltage may not be a code problem for multiple outlets on a circuit, but the amperage can be.


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## runswithscissors

Topmax: Thanks for the clarification.


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## TopamaxSurvivor

The International Residential Building Code E3702.5 that I see Goggling just refers to National Electrical Code 210.23 (A). It requires certain required circuits be limited to a single outlet, but I do not see any wording that limits multiple outlets to circuits of no more than 20 amps. The code does not generally limit the number of devices, it limits the load on the circuit. Often the loads of devices are interpreted to limit the number, but this is a endless gray area for debate.

REO, I was just trying to explain the operational differences between the European utilization voltage at 220 and the US 120/240 systems so the layman might understand it. The importance of the ground in the US cannot be exaggerated. To be without it is like driving a car without brakes!


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## TopamaxSurvivor

U R welcome. For 45 years I have wondered why they did not standardize cable nomenclature? ;-(


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## runswithscissors

I do remember a time when 110 circuits, and tools, were not grounded. How many people still use the adapter plugs in old 2 slot receptacles? You might if you have an old house that hasn't been rewired. And of course when you use the adapters, you're supposed to connect the little green wired pigtail to the (metallic) outlet box, which is supposed to be grounded via metallic conduit. But I suspect very few people bothered to do that, or even check.

I know I didn't.


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## TheFridge

You generally don't daisy chain many heavy loads above 20A because the size of the breaker required would exceed what is required for each piece of equipment.

In some situations you can, but when it comes to large motor loads, the overloads (equivalent of the little button on your saw motor) are generally located immediately after the breaker and are to be sized for that motor only.

And if you didn't want to run a bunch of motor feeders, you'd just run a single feed to a tap box or a sub panel closer to the motors. Sized per all motors.

" cord and plug with 15A wiring, which predictably overheated and started melting things. We were fortunate that it didn't start a fire. In the future I'll always confirm that the wiring configuration is correct when I buy a large appliance or piece of machinery used."

The wirenuts melting off tells me the problem was in the connections and not the cord. Unless the whole cord melted from beginning to end.


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## REO

Topa, I agree whole heartedly with the necessity of a ground for safety! and understood your description (I helped a friend in the Seychelles with some wiring). In discussions with people I usually use the anallogy of driving home from the bar. people do it all the time it can be done but it is always unsafe and can hurt more than just one person. Just because it works doesn't make it right!

Why me, You may have something there as far as the amperage is concerned.


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## intelligen

> " cord and plug with 15A wiring, which predictably overheated and started melting things. We were fortunate that it didn't start a fire. In the future I'll always confirm that the wiring configuration is correct when I buy a large appliance or piece of machinery used."
> 
> The wirenuts melting off tells me the problem was in the connections and not the cord. Unless the whole cord melted from beginning to end.


That makes sense. I just threw the cord away and didn't strip the outer jacket off all the way, but insulation around the individual wire(s) might have been melted along the entire length of the cord. At the wire nut end of the cord, about 4" of the hot wire's insulation was melted (all the way back to the outer jacket). Not sure if it was related or if it was a separate issue, but at the other end of the cord, the rubber around the prongs was bulged out, and the receptacle had burn marks and the prong holes were deformed.


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