How fast does a contactor open a circuit after control power loss?

I guess this would be measure in milliseconds. Can you direct me to a spec sheet to verify?How fast does a contactor open a circuit after control power loss?
Straight from the power source, I measured closing time on a work bench at 0.1 sec. It stays fairly constant for different models.





Opening time should be much shorter, I would guess a 10th of that, i.e., 0.01 sec but, as pointed out, may depend on the inductance/capacitance of the control circuit, PLUS the time it takes for the arc to quench. So, play safe, and asume the same time as for closing, i.e., 0.1 sec.


.How fast does a contactor open a circuit after control power loss?
The spec sheet for the contactor may give you this and it will vary depending on the contactor.





Its actually quite slow in protection terms and should not be used in protection scheme for short circuit. I have never known a reason to question it. It may not even be constant.
milliseconds
This would depend upon 2 things.





the capacitance of the circuit and the reluctance of the solenoid holding the points (open/closed)





there will also be a lag associated with the mechanics.





for example my pump relay takes about 50 msec for the voltage to drop below that necesary for the solenoid to relax, once the field collapses, the spring must then push the plunger away from its stop.
A contactor opens a circuit after a loss of control power in a split second. Why dont you surf www. Allen Bradley contactors.