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#12 AWG Copper. (The previous answer, "12/2 with ground", was incorrect. That answer specifies Romex. Not all homes are wired in Romex, and if they were, it would be acceptable to use any number of conductors inside the cable, including 12/2, 12/3, 12/4, and even the "new" 12/2/2.) If you receive free breakers with a "panel kit", and they are 20A breakers, keep in mind you cannot use them where a 15A breaker was previously. The wires on the 15A breakers is likely 14 AWG which can overheat and cause fire if installed on a 20A breaker. The 'weakest link' is supposed to be the breaker, not the wire. -------------- If you do not understand the work well enough to accomplish it yourself properly and safely, don't try it. Consult a professional electrician, as they are proficient enough to do it properly and safely.When working on electrical circuits and equipment, make sure to de-energize the circuit you will be working on. Then test the circuit with a definitive means to make sure it is off (multimeter with metal tipped leads, voltage tester with metal tipped leads, etc., not a non-contact tester, which is non-definitive.)

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โˆ™ 2008-08-24 01:46:39
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Q: What is the minimum size wire on a 20A breaker?
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Related Questions

What wire size do i need for a 240v 20a compressor?

If you have to ask here, you shouldn't be trying to wire in a 20A compressor. You will require a special circuit for the voltage and current with an independent breaker. Check your local code for the wire size or talk to a qualified electrician.

Can you safely change a 20 amp breaker to 30 amps?

No, this is not a recommended procedure. The breakers main job is to protect the wire that is connected to it. A 20A breaker will have a #12 wire (rated 20A) connected to it. A 30A breaker will have a #10 wire (rated 30A) connected to it. As you can see if you use a 30A breaker on a #12 wire you could overload the wire by 10 amps. I have seen an incident where the insulation has melted off of an overloaded wire, the wire short out and a fire start before the bigger size breaker tripped. DON'T DO IT.

What size wire to feed a panel with 50A breaker for hot tub and 20A branch circuit?

#6 3 conducter

Can you wire a 12 2 wire to a 20A 240V circuit breaker to get a 240V for an electric heater?


What size amp circuit breaker should be used for a geyser?


What size wire do you use to install a 20A breaker for a 230V receptacle for use with a 230V air conditioner?

A #12 copper wire with an insulation factor of 90 degrees C is rated at 20 amps.

What size wire for 277 volt 1ph 13.2 amps heater?

depends on length of circuit, continuous duty or not. not knowing these factors i would say 12awg on a 20a breaker.

Can you change 15 amp to 20 amp outlet?

You can replace a 15A outlet with a 20A outlet. However you need a circuit protected by a 20A breaker or fuse and 12 AWG wire to run 20A through the circuit.

20 amp breaker power verse 15amp breaker power?

The 20A breaker can handle (25%) more power than the 15A breaker, because of this the wires used inside the walls is larger. Some circuits must be 20A, the laundry and kitchen are examples of 20A circuits.

What size wiring do you need to wire in an electric water heater?

a # 12 wire is inadequate a typical 60gal electric water heater takes 20 amps this is a permanently connected permanently installed load this is too much for #12 wire it will never see less than 20A you must use the next larger size wire #10 20A fuse will blow in 20 minutes with 20A load it must be next larger size 30A fuse will protect #10 wire 25A fuse will carry 20A for indefinite period if you have several people who like to shower with warm water you will see 20A for 5 hour periods <<>> New homes will be wired for a 40 gallon tank. This will be a # 12 wire rated at 20 amps on a two pole 20 amp breaker. A 4500 watt tank will draw 4500/240 = 18.75 amps.

4800 watt heater that's 240 volts What size breaker is needed?

Technically it's a 20 amp load (20A x 240V = 4800W). However, you should not run a breaker at full load. The breaker is to protect the wiring from overheating and from short circuits. You should use 10 gauge wire and a 30 amp double pole breaker.

What minimum number of 150 W light bulbs must be connected in parallel to a single 240 V household circuit to trip a 20.0 A circuit breaker?

150W = 240 volts * .625Amps. Assuming the 20A breaker trips at exactly 20A, 20/.625 = 32 lights.

How many outlets can you put on a 20A breaker?


Has anyone ever tried to experiment with 14 2 on a 20A breaker?

Its a safety thing. 20amps on that thin of wire will heat the wire up too much. Its a fact; not a story. 14 amp wire is not ok to put on a 20 amp rated device!!!! your wire will burn before the breaker will trip and will start a fire!!!!

What number wire gauge for a single pole light switch?

In residential wiring applications the most used is 14 gauge wire for light switches as long as the circuit breaker or the fuse is 15A. If your lighting circuit is on a 20A fuse/circuit breaker then you need to use 12 gauge wire

How many amps on each wire for a 20 amp doublepole breaker?

Each wire on a two pole 20 amp breaker will allow 20 amps maximum before the breaker will trip.

Can you plug a 220 dryer in an 220 aircondition plug?

Probably not, the pin configuration of a 30A dryer plug should be different from a 15 or 20A A/C plug. The demand draw of a dryer is higher than that a A/C unit and would trip the 15 or 20A breaker. By putting a bigger breaker on the A/C circuit would not be a good idea either because the wire size to the A/C plug would then be under sized.

If a circuit breaker is a 30A 240V for a dryer and the dryer calls for a 20A do you need to change your breaker?

No, you're fine. Breakers are mainly used to protect the wires (and people), not the appliance. The appliance should have its own overcurrent protection (a fuse usually). The 30 amp breaker will work in this case. First off, dryer outlets are usually 30A as a standard, just like normal wall outlets are 15A. Secondly, you want your expected load to be 80% of your breaker size. So, a 20A load would call for a minimum 25A breaker, they just rounded up to the standard 30A breaker. (Which has a maximum expected load, by this rule, of 24A.) Good question though.

What are the electrical requirements and how do you convert a 15A circuit breaker to a 20A circuit breaker?

Please be more specific....simply replacing the breaker with a 20 amp may cause a fire; if the cable is sized for 15 amp and is overloaded. Your 15 amp breaker is probably feeding #14 wire. The use of a 20 amp breaker requires at least a #12 wire be used. Fire hazard if breakers and wiring are not sized correctly.

What gauge wire for 20A?

12 AWG.

What does 20A CB stand for in a car fuse?

20 amp circuit breaker

Can a regular 120 volt outlet be converted to a 120 v 20 amp single phase simply by changing the breaker and rewiring the outlet want to use a mig welder occasionally?

If you have 12/2 wiring in this circuit and a 20-amp breaker controlling it, you can THEORETICALLY do it, but you've got another problem: according to code, if you've got a 20-amp breaker and a 20-amp outlet, you're only allowed to have one outlet in the circuit on the theory that a 20-amp outlet is going to have a 20-amp appliance plugged into it. If you want more than one outlet, you'll need to use 10/2 wire and a 30-amp breaker.If you are asking this question, it implies you are not qualified to do the work. Hire a licensed electrician!If the breaker is not already 20A, then absolutely not! An existing 15A breaker will have #14AWG wire to the outlet(s). For a 20A circuit, you must have a MINIMUM of #12AWG. If you try to push 20A through #14 wire, you could start a fire, not to mention it is illegal.15A and 20A outlets are wired exactly the same, one just has a higher rating than the other.A regular 120V outlet is already single-phase.So, your question really is: Can an existing 15A, 120V circuit be converted to a 20A circuit by simply changing the breaker and receptacle to 20A? : No, the breaker, wiring, and receptacle(s) must ALL be changed to be safe and legal.If the breaker is already 20A, and the wiring is already #12, then no modification is necessary. You are good to go as-is.Tip: If your house has an outlet for a washing machine, check the breaker for it. Washing machines are supposed to have their own dedicated circuit, and that circuit is required to be 20A according to NEC article 210-11. You could use that outlet temporarily to do your welding.IF YOU ARE NOT ALREADY SURE YOU CAN DO THIS JOBSAFELY AND COMPETENTLYREFER THIS WORK TO QUALIFIED PROFESSIONALS.If you do this work yourself, always turn off the powerat the breaker box/fuse panel BEFORE you attempt to do any work AND always use a meter or voltage indicatorto insure the circuit is, in fact, de-energized.if the wire is #12 or higher, then yes you can swap the breaker and receptacle. however, without ripping your drywall apart there is no guarantee that is #12 the entire run. back to your panel. if ihe wiring is open and you can verify its indeed 12 gauge....go for it.

Can a 20A circuit that trips often be changed to a 30A unit if the attaching wire is at least 10 gauge?

NO! The circuit is being overloaded. Danger of fire will result from just changing the size of the fuse or breaker. A 30 amp breaker may be used with #10 wiring. #10 is rated for 30 amps. I would be hesitant to do this if the tripping problem is something new though.

Can I use 20 amp receptacle 12 gauge wire and a 15 amp breaker in a circuit?

Yes. The breaker can be smaller, but not larger than the circuit it is protecting. The situation you describe would normally be protected by a 20A breaker, but what you suggest is fine. You couldn't go the other direction and use a 30 A breaker because it wouldn't protect the lesser rated components.

How do you upgrade from 120V 15A to 120V 20A or from 240V 20A to 240V 30A?

You have to replace the wire (as you are increasing the current capacity), the outlet, and the breaker. Essentially you have to remove the old circuit and put in a new one. You can't reuse parts of the old circuit as you are increasing the current capacity and they would be underrated.