If you have a 2 pole circuit breaker box and cannot get your 240V electric dryer to work should you place 30A on both sides of the box if you purchased a 30A receptacle that reads 125v250v?

Answer 1

Answer for trained people:

There is one mistake that a knowledgeable person can make, and wonder why it doesn't work. This happens in some breaker boxes if you place a skinny 240 volt breaker filling an odd location (counting down vertically) and the next even position below that. When this happens, both hot lines are on the same leg. So, instead of 240 volts across the motor, you have no voltage across the winding, but the motor winding is entirely at 120 volts with respect to ground. The upper position of the breaker location must be an even position, and the lower position the next odd position. Most breaker boxes alternate bus legs in horizontal strips, not vertical rows. The first two horizontal rows are on leg 1 (L!), the next two horizontal rows are on leg 2 (L2), the next two rows are leg 1, etc. This requires placing a double pole breaker where it spans both legs L1 and L2.

The following condition will occur if you have duplex breakers installed in your panel. This error happens most often when the number of breaker positions already used in the box is a multiple of 4, and you try to use the next available space on one side. The next two spaces on one side both have the same leg, so you can't put a 240 volt breaker there. But some of the boxes let you install it there anyway (mine has plastic bosses that prevent this).

You can use a voltmeter to check for this. If you measure 120 volts from each hot prong to ground, but no voltage between the hot prongs, this has happened. A neon voltage tester will show no voltage between the hot prongs, even though it shows voltage from hot to ground.

The cure is to move the breaker down one breaker space in the breaker box. You can put another 120 volt breaker in the empty space where the knockout was removed (since cover is required, and the knockout can't be put back), and reserve it for a future 120 volt circuit. (Since my box has wide knockouts, I had to install two dummy 120 volt breakers, one above the 240 volt breaker, and one below it. But they quickly found uses in extra 120 volt circuits.) NEVER use two single pole breakers for a 240 volt circuit, unless the handles are common tied together with a special device made for that purpose.

Answer 2

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.

Answer 3

No, connecting a 30A receptacle to a 2 pole circuit breaker box with 30A on both sides will not provide the correct voltage for your electric dryer. You need to have the circuit breaker box configured for 240V to match the voltage requirement of your dryer. Ensure the wiring and connections are correct to provide the proper voltage for your appliance to function safely and effectively.

Answer 4

if i have a breaker that has a 120/240v and my dryer has a 240v plug can i change the receptacle to a 240v