Tip & How-To about Microwave Ovens

How to test for Electrical power

Be absolutely certain the power is turned off before you begin. To do this, check the clock, timer and oven light, and examine the heating elements on all settings. If any of these components operate, you have power. If a wiring problem has short-circuited one leg of the circuit you may have 110 volts but not 220. This means the oven light, clock, and some heating elements may operate on low, but not on high. It also means you have power and could get a jolt. A jolt from 220 volts can be fatal, use caution!

Once you are confident the oven has no power it is time to establish if the problem is the house wiring or the oven itself. Check the housebreaker or fuse and then test for power where it enters the oven. If there is a 220-volt wall plug, disconnect the fuse or turn the breaker off, then pull the oven away from the wall and pull the plug. Turn the breaker back on and test the wall outlet. Also check the terminal block, located just inside the back of the unit. This is where the main power cord attaches to the oven circuitry.

If your oven is wired directly into the house, the wiring will be connected to the terminal block. Follow the steps above and while the power is off, locate the three-wire terminal block and inspect it for signs of damage, overheating, or melted terminals. Some installations have 4 wires. The 4th wire is a ground for the cabinet. Ensure all wiring is clear and remember not to touch bare wires or terminals. To check the terminals for power, turn the breaker or fuse on briefly and check the terminal block for power across all three legs. Then remove the power at the breaker fuse.

If the terminal block is receiving power, then the problem is within the oven and you will need to isolate the problem using the wiring diagram, found on the back of the oven in a plastic pouch, or on the back or inside the oven near the broiler.

If the terminal block is not receiving power, your house wiring may be the problem. Should this be the case, you will need to call an electrician.


REMEMBER YOU ARE WORKING WITH 220 VOLTS - USE EXTREME CAUTION!!!

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1 Answer

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