Contactors are large relays that are often used to switch current to electric motors or other high-power loads. They are designed and built to perform the same task over thousands of cycles, so it is important that they operate correctly.
To wire a contactor, you will need a hot (AC) and neutral wire to the A1 or A2 terminals on the contactor coil (these are interchangeable). Then you will need your line side (black, red and blue) wires to the L1, L2 and L3 terminals on the contactor. You can use a crimp-on to connect the wires together, which will ensure that the connection is solid and long lasting.
If you have any trouble connecting the wiring or are unsure what wires go where, be sure to check the diagram on the back of the contactor for reference. This will make it much easier to work from when rewiring your system.
Once you have the contactor plugged into a power supply, you will need to wire the coils and the contacts that are connected to the load. You can do this with additional black, red and blue three-phase wire. You can also purchase a pre-made harness that will have the correct wires and connectors already in place for you, saving time and hassle.
Before you start wiring your contactor, be sure that it is rated for the voltage and current that you are using. You can find these ratings in the product specifications for the contactors you buy, or from a building and construction supply store, or even some larger hardware stores.
When you are ready to install the contactor, it is a good idea to double check that the coil on the contactor has been properly energized by a 24 volt DC source. This will help to prevent you from accidentally frying your contactor, and keep it working smoothly.
What Are Auxiliary Contacts On A Contactor?
Auxiliary contacts are a type of contact on a contactor that are used to provide an output signal to the isolated part of a circuit when the contactor has been energized. These auxiliary contacts are not normally closed (no continuity without power on the coil) and can be used to switch between different voltages, depending on the contactor’s configuration.
These contacts are usually made of aluminum, but can be made of other materials as well. They are designed to withstand extreme temperature changes, arcs and mechanical stress and erosion.
They are also rated to resist a wide range of currents, and can be used for both low-current applications as well as for DC current. They are available with either a top saddle clamp or bottom flat clamp, and have ridges on the contactor to provide extra mechanical stability.
To use an auxiliary contact, you will need to attach the ac terminal on the ac contactor to one of the ac output terminals in your control circuit. Then you will need to use the other ac terminal on your contactor to connect your auxiliary contact. Once you have both of these connections made, you can test that the contactor is working by turning the power on and off to see how it operates.