Is a double pole 30 amp breaker just 2 15 amp breakers side by side, doubling the voltage, or is it 2 30 amp breakers side by side?
Hi ssyyzzxx. The amperage rating of the breaker is the number that is stamped on the breaker. If it says "15", then it's a 15 amp breaker. If it says "30", then it's a 30 amp breaker. In other words, you are not required to do any math to determine the amp rating for the breaker. Since it is a double pole breaker, it is double the Voltage of a single pole breaker installed in the same Panel. So, if your panel is 120/240 volts like a standard residential panel, then your double pole breaker is rated for 240 volts.
Thanks, Jason. Here's the reason I asked: I have an old oven that I think draws 40 amps but it's fed by two linked single pole breakers marked 20 amps. Can that be? Should the individual breakers both be marked at 40 amps?
Yes, a 40 amp breaker would be marked "40". If your oven is connected to a double pole 20 amp breaker, and it's an oven ONLY, with no cooktop on the same circuit, it's possible that it draws less than 20 amps. It should be marked somewhere with an amperage requirement, or you can use an amp Meter to read the amperage drawn by the oven when it is on.
Thanks. So, in conclusion then -- whatever the amperage draw of a 110/220 appliance both individual breakers (if there were two indidual breakers linked instead of one one double pole) will be marked at that amperage. A forty amp oven would be fed by two 40 amp individual single-pole breakers or one 40 amp double pole breaker. Correct?
That's correct. By the way, the electrical Code only allows 2 single pole breakers to be used as a double pole breaker if they are linked by an "approved" handle tie.
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