How to Check Power in an Electrical Panel
- 1). Remove any screws securing the dead front covering the breakers. Pull the dead front out of the panel to expose the hot connections inside. Check that all of the white and bare wires connected to the ground and neutral buses are tight.
- 2). Set your voltage tester at its maximum alternating current scale. Touch the black lead from the tester to the neutral bus inside the panel, where all of the white wires are connected. Touch the red lead to each of the screws connecting the two large main wires feeding the panel. Each should have 110 volts or or slightly less. If one or more of the feed wires isn't showing voltage, or is showing a low voltage, then the problem is with the power company.
- 3). Touch both leads from the voltage meter to the two feed wires, one lead to each feed wire. You should see 220 volts or close to it, on your voltage meter. If not then the power company should be called to come out and repair the problem.
- 4). Touch the black lead from the tester to the neutral bus again and test each of the breakers with the red meter lead. Touch the red lead to each screw where the black or red wires connect to the breakers. Each breakers screw should show around 110 volts on the tester. If one doesn't show 110 volts, try resetting the breaker by pushing the switch all the way to the off position, then push it back to the on position. If there is still no power after resetting replace the breaker.
- 5). Test breakers with a reset button or ground fault circuit interrupter and archfault breakers by touching the black lead from the tester to the silver screw on the breaker where the white wire attaches. Touch the red lead from the tester to the brass screw where the black wire connects. The tester should show around 110 volts. If you try to test these types of breakers with your black lead on the neutral or ground bus the reset button should trip and kill power to the circuit. Pushing the test button should also trip the breaker. Replace any breakers that don't test properly.
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