Answer / kj

They are the ratings of the contactor.

AC1 is for resistive loads and AC3 is for normal motor
loads. AC2 is for special conditions of motors.

Answer / pani

Relay types
Ac1-Noninductive loads (pf 0.95).
Ac2-Slip Ring Induction Motor.
Ac3-Squirrel Cage Induction Motor.

Answer / muttappa

AC1,is for resistive load and
AC2, is special conditions of motor
AC3,is for normal motor loads

Answer / nitin tyagi

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.

Answer / abdul rehman khalid

This applies to all AC devices (loads) with a power factor of at least 0.95 (cos phi greater than or equal to 0.95). 
Example of use: resistive load, heating, distribution.
This applies to squirrel cage motors where breaking occurs while the motor is running. 
Example of use: all squirrel cage motors, lifts, escalators, conveyors, bucket elevators, compressors, pumps, mixers, air conditioning units, etc.

Answer / abdul rehman khalid

AC1..This applies to all AC devices (loads) with a power factor of at least 0.95 (cos phi greater than or equal to 0.95). 
Example of use: resistive load, heating, distribution.
AC2..This applies to squirrel cage motors where breaking occurs while the motor is running. 
Example of use: all squirrel cage motors, lifts, escalators, conveyors, bucket elevators, compressors, pumps, mixers, air conditioning units, etc.

Answer / vimal dobal

AC1, AC2, AC3..are like a normally auxallery contector. Use
to indirect operation of High reated power contractor.

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