How to Calculate a Breaker Panel Load
- 1). Open the door to your breaker panel.
- 2). Determine the amperage rating for each circuit breaker. The amperage rating is typically an integer between 15 and 50 (although it can be higher) followed by a capital "A." The rating will be printed on the breaker's Reset switch.
- 3). Add all the ratings you determined in Step 2.
- 4). Multiply the sum from Step 3 by 0.8. To protect circuits from power surges, electricians will generally use a breaker with an amperage rating 25 percent higher than the actual load created by the appliances attached. By multiplying by 0.8, you are correcting for this safety feature.
- 5). Multiply the result from Step 4 by 120 volts. This will give you the total breaker panel load, in volt-ampere (VA) units.
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