Suppose that the two AC contactors are contactor A (normally closed auxiliary contact a) and contactor B (normally closed auxiliary contact b). Use the normally closed auxiliary contacts a and b of A and b to accomplish the interlocking function.
Expanded information:
The working principle of the contactor is: when the contactor coil is energized, the coil current generates a magnetic field, and the resulting magnetic field causes the static iron core to generate electromagnetic suction to attract the moving iron core, and drives the AC contactor point action, and the normally-closed contacts are broken.
Normally open contacts closed, the two are linked. When the coil is disconnected, the electromagnetic suction disappears, the armature is released under the action of the release spring, so that the contacts are restored, and the normally open contacts are disconnected, and the normally closed contacts are closed. The working principle of DC contactor is somewhat similar to that of temperature switch.
Power electronics technology has developed rapidly, people will power electronic components applied to the DC contactor, cleverly created a hybrid DC contactor, making the DC contactor to intelligent, controllable step forward. This hybrid contactor utilizes the advantages of small contact resistance and small on-state voltage drop of the traditional DC contactor in the closed on-state.
The contactless switch composed of anti-parallel thyristor and control module unit*** is connected in parallel to the traditional DC contactor contacts. This contactless power electronic switch breaks the circuit without generating an arc, which avoids the electrical abrasion of the contact material by the arc in the traditional contactor, and also greatly increases the service life and reliability of the contacts.
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