How do you connect a 120-volt coil to a contactor?

How do you connect a 120-volt coil to a contactor?

Connect the cable from the 120 VAC electrical supply to the switch's top screw terminal. Connect another wire to the switch's second screw terminal. Connect the other end of that wire to one of the screw terminals on the contactor's 120 VAC coil. The contactor's coil will now be connected to the power source, but only when the switch is in the ON position.

If you want the contactor to always open when you turn off the power, then it will need to be wired into a COIL TRIGGER. These are available for contactors and should be used instead of wiring the contactor directly into every circuit where it's needed.

A COIL TRIGGER will hold the contactor's coil "on" while allowing it to close under the control of a magnetic force created by a tripped breaker or unplugged cord. This type of trigger can also be used with contactors if you want them to operate separately from your main breaker panel. For example, if you have a garage door opener located in the basement that doesn't need to be closed during an emergency, you could connect its coil to the secondary side of the contactor. The contactor would remain open while the breaker connecting to its primary side was opened. Then, if there was a fire in the basement, the magnet on the COIL TRIGGER would pull the contactor's coil closed so the garage door would close automatically.

How are lighting contactors wired?

Connect the wire from the switch to one of the transformer's low-voltage terminals. Connect another wire from the transformer's second low-voltage terminal to one of the contactor's control terminals. The third wire should be connected only to the other control terminal on the contactor.

The contactor is now ready for operation. Open and close the circuit between the two wires from the transformer to start and stop the motor, respectively. The contactor will open the motor's power circuit when it detects zero voltage across its terminals, indicating that the motor is off. It will close the circuit again when it detects any voltage, meaning that the motor is on. If you connect all three wires from the transformer to both control terminals on the contactor, the motor will run continuously until it is shut off by one of these methods.

Contactors are available in either magnetic or electronic versions. Magnetic contactors use a metal armature attached to a spring-loaded plunger that opens and closes the circuit as it passes over a magnet. Electronic contactors use semiconductor components instead. They are more durable than magnetic contactors but also more expensive to purchase and install. Also, they cannot be used with motors that operate on 120-volt power because they require at least 14 volts to work properly.

How do you wire a SunPro tach ignition coil?

Using a wire splice, connect the white wire to the dimmer switch control wire. Insert the dimmer switch wire into one side of the splice and the tachometer's white wire into the other. Connect the green wire to the ignition coil's negative terminal. Finally, connect the red wire to the positive terminal on the ignition coil.

How do you test a magnetic contactor coil?

Using the designations T-1, T-2, and T-3, identify and mark each wire. This ensures that each wire has a corresponding side and also prevents any misinterpretation in the subsequent steps. To ignite the coil in the contactor, turn on the control switch. There should be a distinct clicking and buzzing sound. This means that the coil is now energized and will close the main contact when needed.

Now check if all the markings are correct. If one or more wires are identified as T-1 when they should be T-3, then there is some kind of mistake in the wiring diagram. This could be due to someone cutting one of the wires off after it was already attached to something important. In this case, the missing piece will not be able to carry an electric current and will show up during the test as no voltage when probed with a meter.

If everything is correct, then there must be another problem with the coil. It may be defective because of corrosion on the wire insulation or even metal fatigue from constant opening and closing. Before buying a new magnetic contactor, make sure that its packaging says it comes with test buttons/pins so you can perform these experiments yourself before buying it.

About Article Author

Richard Ollar

Richard Ollar is a freelance writer and blogger. He loves to write about all sorts of things: from cars to weaponry. His favorite topics are technology and history. Richard has been writing about these subjects for years, and he really knows his stuff!

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