A class 1 contactor should be mechanically sound to withstand
Right Answer is:
0.025 million times
Mechanical endurance:- 1 million no-load operating cycles. This represents the number of no-load operating cycles which can be made before it becomes necessary to service or replace any parts other than contacts.
Duty Class 1:- For use in systems where the power factor of short-circuit current is extremely low, e.g., where the switchgear is connected in relatively close proximity to the source of generation. Duty Class 1 is the normal or medium requirement contactors.
For MV contractors such minimum requirements might be specified as:
- Mechanical endurance (i.e. off-load) 25,000 operating, cycles or 0.025 million times
- Electrical endurance (i.e. on load) 5,000 operating.