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in this data sheet:

Rated Operational Current AC-1 (Ie):
(690 V) 40 °C 100 A
(690 V) 60 °C 80 A
(690 V) 70 °C 70 A

is mean that the operating voltage must be 690 vac to get this nominal current? and isnt feet to 400?


RE: contactor

The AC-1 current rating is at a voltage up to and including 690V AC.

I'm not really sure what you mean by "and isnt feet to 400?".

RE: contactor

i mean 400vac
what i consider that if you use ac-1 load must be 690vac operating voltage to get this current
but from your answer you mean is up to and including 690V AC.
so why at ac-3 i have Different voltage and current

Rated Operational Current AC-3 (Ie):
(220 / 230 / 240 V) 60 °C 53 A
(380 / 400 V) 60 °C 53 A
(415 V) 60 °C 53 A
(440 V) 60 °C 53 A
(500 V) 60 °C 45 A
(690 V) 60 °C 35 A

RE: contactor

You understand ACAN-1 d AC-3 correct?

Those values are the tested and posted results. If you want heavier duty or longer life you must constrain use to the lower voltages and current values.

Keith Cress
kcress - http://www.flaminsystems.com

RE: contactor

No, the current is a finite amount (given the temperature limitations they show) that the contactor can safely handle, the voltage is simply the MAXIMUM it can safely be used at. So if used at 40C, the contactor can handle 100A at 690V, 100A at 400V, 100A at 240V, 100V, 31.27V, etc. etc.

" We are all here on earth to help others; what on earth the others are here for I don't know." -- W. H. Auden

RE: contactor

AC-1 - This category applies to all AC loads where the power factor is more than 0.95. These are primarily non-inductive or slightly inductive loads, such as heating. Breaking the arc remains easy with minimal arcing and contact wear.

AC-3 - This category applies to squirrel cage motors with breaking during normal running of the motor.
On closing, the contactor makes the inrush current, which is about 5 to 7 times the rated full load current of the motor.
On opening, the contactor breaks the rated full load current of the motor.

Based on your load type matching above, select the correct contactor rating. Else you may end up in decreasing the life of contactor.

If your voltage is 415V, then rated current for AC-3 load at 60deg is 53A. you can correct the current rating based on your amb temperature correction factor.


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