Many of the large pieces equipment are directly powered from high lines of voltage. In most homes, these lines are far exceeding the AC standard of 120V. 240V AC and 480V AC are used commonly for large kinds of equipments such as industrials machines, motors and household appliances like dryers and washers. These kinds of voltages must be isolated electrically from the 120V standard AC. The AC contactors are utilized in order to provide the required isolation. They use 120V standard AC power in energizing a magnetic coil that causes several sets of internal contacts to provide and close a high power to equipment. Here are some tips on how to wire a Contactor:
Get the Contactor – Ensure that the contactor contacts are both rated in current and voltage in order to handle the required load of the equipment that is being powered. The contactors can be bought in construction and building supply stores and large hardware stores.
Study the manufacturer information of the contactor – Manufacturer information will determine the 120V AC Contactors Control of 2-input pins and more than two sets of contacts output should be identified. Some of the contacts labeled are indicated as NC (normally closed) and NO (normally open). Also, these contacts are shown as a line drawing from one contact that ends in a dot and the second line from other contact that is near the dot, but doesn’t actually touching the dot. (NO contact)
Check the auxiliary outputs of the contact – Some of the contactors include an output contact as a signal to the circuit’s isolated part that the contactor has energized. This output auxiliary contact of AC Contactors shouldn’t be rated at higher voltage instead, it must be rated at 120V AC.
Route the wires – Remove the entire energy to the wires. Run all of the output and input wires to the contactor. The wires should be rated through the information provided by the manufacturer. Use a wire stripper when cutting out the excess lengths of the wire however, you need to ensure that the wires are long enough in reaching the intended contact.
Strip the wires – By using the wire stripper, strip a half inch from both ends of the wires. If your wire is a stranded type, you need to twist the stripped part in order to ensure that the strands are intact, and no piece is hanging before connecting them in AC contactors. The stray strands can possibly make unintentional contacts with the parts of the equipment which may cause problems and damage.
Wire the auxiliary contacts and inputs – Loosen the screws in contact blocks for wires by using a screwdriver. Insert the wires in to the contact block while making sure that no insulation are attached to the block. Check if there are no stray strands jutting out from contact block. If no stray strands are found, tighten the screws back on contact blocks.
Energize the contactor – Apply the controlled voltage on its input. Listen as the AC contactors click as it engages. De-energize your contactor.
Connect the Outputs – Put each of the stripped ends of the wire into its designated contact block. Just like the way you’ve checked on wiring the auxiliary contacts and inputs, you also ensure that no stray strands are jutting out from its designated contact blocks. Tighten the screws back after you have checked the wires.