Hooking Up a Door Bell to a Transformer
- 1). Turn off the electrical power to the doorbell transformer.
- 2). Test the transformer's two output terminals with a voltmeter to ensure no power exists. Place one probe of the tester on either terminal and the other probe on the remaining terminal. A voltage reading of zero (0) verifies that the power is off. If you get any other reading, you need to check your circuit breaker again to ensure that no power runs to the system while you are working on it.
- 3). Strip 1/2 an inch of insulation from the doorbell wire and the bell switch wire using wire strippers. Doorbell wire is typically 18-gauge solid copper.
- 4). Bend a loop in each end of the stripped wires using a pair of needle-nose pliers.
- 5). Loosen the two terminal screws on the transformer using a flathead screwdriver. Turn the screws counterclockwise.
- 6). Attach one wire to either terminal and tighten the terminal screw clockwise with the screwdriver. Connect the other wire to the remaining terminal and tighten.
- 7). Restore electrical power.
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