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AC/DC dual-use AC contactor?

It can be seen that the difference between the two is quite large.

Now I go back and forth to solve the main problem:
1) In addition to the coil, what is the difference between the DC contactor and the AC contactor structure type?
2) If the coil is connected according to the rated current, and the current and current amount are similar, the AC power and load are connected to the contact point of the DC contactor, or the DC stabilized power supply and the load are connected to the AC contactor, what will happen? question?

Answer to question 1:

The coil of the DC contactor is tall and thin, while the coil of the AC contactor is short and fat. Therefore, the coil resistance of the DC coil is large, and the coil resistance of the AC coil is small.
Double coils are common in DC contactors and DC relays, in which the current coil is used to pull in, and the working voltage coil is used to pull in and maintain.
The AC contactor is a single coil.
The transformer core and connecting iron of the DC contactor are all welders’ soft iron, and the AC contactor is a ferrite core lamination to reduce communication damage.
The magnetic flux in the AC contactor core changes alternately and exists above the zero point. At this time, the connecting iron can rebound under the effect of axial force, and then digest and absorb after zero. Therefore, the AC contactor core must be equipped with a short circuit fault ring to clear the zero oscillation.
AC contactors and automotive relay coils can cause overvoltage when released. DC contactors and automotive relays are usually cleared with reverse diodes, and AC contactors and automotive relays are cleared with RC circuits for overvoltage.
The contact point of the DC contactor is difficult to extinguish the arc, so it should be equipped with a magnetic blowing arc. The AC contactor is relatively easy to extinguish the arc, and the C-shaped structure and arc extinguishing grid can be selected.
Answer to question 2:

When the effective value of the DC voltage and the AC current is the same, the coil current of the DC contactor is smaller. Therefore, when the two switching power supplies are interchanged, the DC contactor is likely to be unable to digest and absorb, and the AC contactor will ignite immediately.
In addition, when the DC contactor receives the AC circuit, the freewheeling diode of its supporting facilities is immediately damaged.