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Wire sizing question

signcrafter

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I have a machine that I need to add an outlet for. The machine came with a NEMA L6-30 plug on it. The label on the machine says 208-230 volts, 60 HZ, single phase. Also says "Max. BR. CIR. fuse or hacr cir. breaker, 20A. And Min Circuit ampacity, 15A.

What size breaker and wire do I need for this? I'm confused because it has a 30 amp plug which I thought got 10 gauge wire and a 30 amp breaker but the label says maximum 20 amp circuit if I'm understanding right.
 
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CNGsaves

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Too little information . . .
. . . .
. . . . What kind of machine ??
. . . . Doesn't the motor plate list HP or FLA ??
 

ddawg16

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Sounds like you need 20A.

Quite often people will use what ever plug/recpt they had handy. L6-30 is pretty common. If it was me, I'd use it if that was what I already had.

Depending on the machine, I might swap out the 30A breaker for a 20A if it was going to stay in operation for any length of time.
 
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signcrafter

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Too little information . . .
. . . .
. . . . What kind of machine ??
. . . . Doesn't the motor plate list HP or FLA ??

Machine is a commercial slushy machine I found for a deal. Going to be used for margaritas. Here is a picture of the label on the machine.

IMG_20160603_083648004.jpg

Sounds like you need 20A.

Quite often people will use what ever plug/recpt they had handy. L6-30 is pretty common. If it was me, I'd use it if that was what I already had.

Depending on the machine, I might swap out the 30A breaker for a 20A if it was going to stay in operation for any length of time.

I need to put in the breaker/wire/outlet. So can I just use a 20 amp breaker and run 12 gauge wire? Then use the L6-30 plug with an L6-30R receptacle? Or do they make a 20 amp plug and receptacle I should use?
 

ddawg16

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Machine is a commercial slushy machine I found for a deal. Going to be used for margaritas. Here is a picture of the label on the machine.

IMG_20160603_083648004.jpg



I need to put in the breaker/wire/outlet. So can I just use a 20 amp breaker and run 12 gauge wire? Then use the L6-30 plug with an L6-30R receptacle? Or do they make a 20 amp plug and receptacle I should use?

If you are going to run wire....and you 'think' there is a chance you will ever need 30a, then run #10 and just feed it with the 20a breaker.

It's a lot easier to swap breakers than wire.
 

wyliesdiesels

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Machine is a commercial slushy machine I found for a deal. Going to be used for margaritas. Here is a picture of the label on the machine.

IMG_20160603_083648004.jpg



I need to put in the breaker/wire/outlet. So can I just use a 20 amp breaker and run 12 gauge wire? Then use the L6-30 plug with an L6-30R receptacle? Or do they make a 20 amp plug and receptacle I should use?

That's refrigeration equipment so u size wire based on the MCA and size the breaker according to the label. So #14 with a 20a breaker. If this outlet will be used for other non refrigeration equipment then just wire with #12 and 20a breaker.

Most likely someone had a 30a plug and used it instead of getting the right plug- a 6-20p.

It is not code permissible to put a 6-30r on a 20a circuit.

Yes u can get a 240v 20a plug and receptacle.
 

nadogail

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IMHO, Because somebody just might plug a 30 Amp load into that 20 Amp circuit.

Then they would possibly overload that circuit, cook the wires because the over current protection failed (maybe the penny under the fuse didn't melt) and next thing you know the Red Truck is at your door with the lights flashing.

My advice guaranteed and is worth exactly what you pay for it.
 
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signcrafter

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Ok so #12 wire with a 20 amp breaker and then use a 20 amp outlet and replace the plug to a 20 amp plug?

Thanks.
 

Rookie2

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Yes. If you look around you will probably find two push in breakers on the rear of the machine, one for the compressor and one for the stirr motor (from what I remember working on one machine).
 

aircommuter

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Use #10 wire 20a breaker , don't worry about the plug. It doesn't matter what anyone plugs in, you still covered. Besides copper prices are down for now.
 
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ishiboo

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IMHO, Because somebody just might plug a 30 Amp load into that 20 Amp circuit.

Then they would possibly overload that circuit, cook the wires because the over current protection failed (maybe the penny under the fuse didn't melt) and next thing you know the Red Truck is at your door with the lights flashing.

My advice guaranteed and is worth exactly what you pay for it.

Huh? A 30A load would trip the 20A breaker, it wouldn't allow any more current than what you could do with a 20A outlet.
 

ddawg16

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Huh? A 30A load would trip the 20A breaker, it wouldn't allow any more current than what you could do with a 20A outlet.

That is my thinking as well. No different than a 20A wall ckt feeding 5 outlets....and someone plugs in 5 irons. What stops them from doing it?

As long as the wire is sized for the breaker.....no issue
 
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signcrafter

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That is my thinking as well. No different than a 20A wall ckt feeding 5 outlets....and someone plugs in 5 irons. What stops them from doing it?

As long as the wire is sized for the breaker.....no issue

So if you were using a 20 amp breaker and #12 wire and could use either a 20 amp or 30 amp outlet/plug which would you use?
 

ddawg16

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If it was me.....I'd wire it for 30A (#10 wire) but use a 20A double breaker.

That way, if I wanted to run something that uses 30A at a later date, all I have to do is swap breakers.

It's kinda like the wiring to my garage....wire is sized for 75A, but I'm using a 50a breaker
 
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signcrafter

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If it was me.....I'd wire it for 30A (#10 wire) but use a 20A double breaker.

That way, if I wanted to run something that uses 30A at a later date, all I have to do is swap breakers.

It's kinda like the wiring to my garage....wire is sized for 75A, but I'm using a 50a breaker

I would but I don't see needing a 30 amp receptacle and I already have the #12 wire so would like to use that if I can. If I need a 30 amp receptacle in the future I can buy #10 wire and put in a new receptacle for that at that time.
 

nadogail

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Huh? A 30A load would trip the 20A breaker, it wouldn't allow any more current than what you could do with a 20A outlet.

Agreed, if the breaker is a good one. Not all breakers are good, for example there are Zinsco and others.

Not all over current protection devices are circuit breakers.

Why settle for only one layer of protection?
 

Norcal

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No reason to overthink this, if cord and plug connected use 12 AWG wire and a 20A breaker, if hardwired from a disco, 14AWG & 20A overcurrent protection.
 
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signcrafter

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No reason to overthink this, if cord and plug connected use 12 AWG wire and a 20A breaker, if hardwired from a disco, 14AWG & 20A overcurrent protection.

Going to be cord and plug. Curious though, why can you use 14 AWG and 20A breaker if it's hard wired to disconnect?
 

Norcal

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Going to be cord and plug. Curious though, why can you use 14 AWG and 20A breaker if it's hard wired to disconnect?

Because of the rules for refrigeration equipment, wire for the minimum, use the maximum circuit breaker allowed, if THHN was used 14 AWG would be considered 20A wire anyway in that application, rather then the normal 15A. NM cable "Romex®" is always 15A with 14AWG. 12 AWG & a 20A breaker w/a cord & plug is simple enough.
 

sberry

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Agree with Norcal here. It wouldn't really be a problem in this case to use the 30 hardware but the 12/20 is the right thing and,,, again the reason the 14/20 would be fine is the hardwire.
When its connected to a recept the rules change but welders often use 50A recepts on smaller circuits.
A compact 240 mig allows 14 wire with 30A breaker to a 6-50 but it would need to be nutted to a larger wire at the terminations, the recept is listed 12 minimum,,,,,,, so one could put the larger recept on a smaller breaker but not a breaker larger than the recept although it could be larger than the wire in some cases.
 
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