Combination switch refers to a switch that is often introduced as a power source in electrical control circuits. It can be used to directly start or stop a low-power motor or make the motor forward and reverse, reverse, etc.
The combination switch is composed of moving contact (moving contact piece), static contact (static contact piece), shaft, handle, positioning mechanism and housing. The moving contact and the static contact are respectively stacked between several layers of insulation pads, and each has a terminal for connecting lines. When the handle is turned, the moving contact of each layer rotates with the square rotating shaft, so as to realize the on / off control of the circuit.
There are 3 pairs of static contacts inside the combination switch, which are separated by 3 layers of insulation plates, each with a wiring post for connecting lines. The 3 moving contacts are insulated from each other, corresponding to the respective static contacts, and are sleeved on a common insulation On the rod, one end of the insulated rod is provided with an operating handle. Each time the handle is rotated through a 90 ° angle, the three groups of contacts can be opened or closed. A quick-break spring is installed in the switch to accelerate the breaking speed of the switch.
(1) Because the on-off capacity of the combination switch is low. It cannot be used to interrupt the fault current. When used to control the motor for reversible operation, the motor must be completely stopped before the reverse connection is allowed.
(2) When the operating frequency is too high or the load power factor is low, the combination switch should be used with reduced capacity, otherwise the switch life will be affected.
(3) When using, please note that the switching times of the combination switch per hour generally does not exceed 15-20 times.
(4) Always check whether the switch fixing screw is loose, so as not to cause the wire crimp to loosen, which may cause the external connection point to discharge, spark, ablate or open circuit.
(5) When repairing the combination switch, pay attention to check the contact of the dynamic and static contact pieces inside the switch, so as to avoid arc ablation of the internal contacts.