AC Utilization Categories IEC 60947

Utilization Categories indicate the type of Load and Duty Cycle of the load basis which selection of Switchgear should be done for the intended application.

Utilization Categories indicate the type of Load and Duty Cycle of the load basis which selection of Switchgear should be done for the intended application.

Utilization Categories defines operating conditions for Switchgear – Contactor, Relay, Circuit Breaker, Fuse, Semiconductor Controllers, Transfer Switch, etc. The Operating Conditions are dependent on the load to be Switched / Controlled.
AC CategoryTypical Application : Load, Switchgear, OperationSwitchgear
Standard
AC 1Load Type: Non Inductive or Slightly inductive loads, with Power Factor greater than 0.95,
eg: Resistive load, heating.
Switchgear: Electromechanical contactors.
Operation: Switching.
IEC60947-4-1
AC 2Load Type: Slip-ring motor.
Switchgear: Electromechanical contactors.
Operation: Switching off.
IEC60947-4-1
AC 3Load Type: Squirrel cage motors.
Switchgear: Electromechanical contactors.
Operation : Starting, Switching off during running.
IEC60947-4-1
AC 4Load Type: Squirrel cage motor.
Switchgear: Electromechanical contactors.
Operation: Starting, Plugging, Inching.
IEC60947-4-1
AC 5aLoad Type: Discharge lamps.
Switchgear: Electromechanical contactors.
Operation: Switching.
IEC60947-4-1
AC5bLoad Type: Incandescent lamps.
Switchgear: Electromechanical contactors.
Operation: Switching.
IEC60947-4-1
AC 6aLoad Type: Transformers.
Switchgear: Electromechanical contactors.
Operation: Switching.
IEC60947-4-1
AC 6bLoad Type: Capacitor banks.
Switchgear: Electromechanical contactors.
Operation: Switching.
IEC60947-4-1
AC 7aLoad Type: Slightly Inductive Household load, eg. Mixer.
Switchgear: Electromechanical contactors for household purpose, eg. Miniature Contactor.
Operation: Switching.
IEC61095
AC 7bLoad Type: Household motor loads, eg; Fan, Vaccume pump motor.
Switchgear: Electromechanical contactors for household purpose, eg. Miniature Contactor.
Operation: Switching, occasional inching, plugging
IEC61095
AC 7cLoad Type: Compensated electric discharge lamp control.
Switchgear: Electromechanical contactors for household purpose, eg. Miniature Contactor.
Operation: Switching.
IEC61095
AC 8aLoad Type: Hermetic refrigerant compressor motor
Switchgear: Electromechanical contactors.
Operation: Manual resetting overload control.
IEC60947-4-1
AC 8bLoad Type: Hermetic refrigerant compressor motor
Switchgear: Electromechanical contactors.
Operation: Automatic resetting overload control.
IEC60947-4-1
AC 12Load Type: Resistive and solid state load with Opto-coupler Isolation.
Switchgear: Electromechanical control circuit devices, eg. Aux Contacts.
Operation: Switching, Control.
IEC60947-5-1
AC 13Load Type: Solid state load with transformer Isolation.
Switchgear: Electromechanical control circuit devices, eg. Aux Contacts.
Operation: Switching, Control.
IEC60947-5-1
AC 14Load Type: Small Electromagnetic loads.
Switchgear: Electromechanical control circuit devices, eg. Aux Contacts.
Operation: Switching, Control.
IEC60947-5-1
AC 15Load Type: AC Electromagnetic loads.
Switchgear: Electromechanical control circuit devices, eg. Aux Contacts.
Operation: Switching, Control.
IEC60947-5-1
AC 20ALoad Type: All.
Switchgear: Switches, disconnectors, switch-disconnectors.
Operation: Switching under no load condition. Frequent operation.
IEC60947-3
AC 20BLoad Type: All.
Switchgear: Switches, disconnectors, switch-disconnectors.
Operation: Switching. Infrequent operation.
IEC60947-3
AC 21ALoad Type: Resistive load with moderate overload.
Switchgear: Switches, disconnectors, switch-disconnectors.
Operation: Switching. Frequent operation.
IEC60947-3
AC 21BLoad Type: Resistive load with moderate overload.
Switchgear: Switches, disconnectors, switch-disconnectors.
Operation: Switching. Infrequent operation.
IEC60947-3
AC 22ALoad Type: Mix Resistive and Inductive loads with moderate overload.
Switchgear: Switches, disconnectors, switch-disconnectors.
Operation: Switching. Frequent operation.
IEC60947-3
AC 22BLoad Type: Mix Resistive and Inductive loads with moderate overload.
Switchgear: Switches, disconnectors, switch-disconnectors.
Operation: Switching. Infrequent operation.
IEC60947-3
AC 23ALoad Type: Highly Inductive load, eg: Motor.
Switchgear: Switches, disconnectors, switch-disconnectors.
Operation: Switching. Frequent operation.
IEC60947-3
AC 23BLoad Type: Highly Inductive load, eg: Motor.
Switchgear: Switches, disconnectors, switch-disconnectors.
Operation: Switching. Infrequent operation.
IEC60947-3
AC 31ALoad Type: Non Inductive, slightly inductive.
Switchgear: Multiple function equipment – Transfer switching equipment, eg: ATS
Operation: Switching. With no rated short time withstand capacity.
IEC60947-6-1
AC 31BLoad Type: Non Inductive, slightly inductive.
Switchgear: Multiple function equipment – Transfer switching equipment, eg: ATS
Operation: Switching. With rated short time withstand capacity.
IEC60947-6-1
AC 32ALoad Type: Mixed resistive and slightly inductive load with moderate overload.
Switchgear: Multiple function equipment – Transfer switching equipment, eg: ATS
Operation: Switching. With no rated short time withstand capacity.
IEC60947-6-1
AC 32BLoad Type: Mixed resistive and slightly inductive load with moderate overload.
Switchgear: Multiple function equipment – Transfer switching equipment, eg: ATS
Operation: Switching. With rated short time withstand capacity.
IEC60947-6-1
AC 33ALoad Type: Highly Inductive load, eg: Motor.
Switchgear: Multiple function equipment – Transfer switching equipment, eg: ATS
Operation: Switching. With no rated short time withstand capacity.
IEC60947-6-1
AC 33BLoad Type: Highly Inductive load, eg: Motor.
Switchgear: Multiple function equipment – Transfer switching equipment, eg: ATS
Operation: Switching. With rated short time withstand capacity.
IEC60947-6-1
AC 35Load Type: Electric discharge lamp.
Switchgear: Multiple function equipment – Transfer switching equipment, eg: ATS
Operation: Switching.
IEC60947-6-1
AC 36Load Type: Incandescent lamp.
Switchgear: Multiple function equipment – Transfer switching equipment, eg: ATS.
Operation: Switching.
IEC60947-6-1
AC 40Load Type: Mix Resistive and Inductive loads.
Switchgear: CPS-Control and protective switching devices, eg. Integral Contactor breaker.
Operation: Control & Switching.
IEC60947-6-2
AC 41Load Type: Non Inductive, slightly inductive. eg: resistance furnace.
Switchgear: CPS-Control and protective switching devices, eg. Integral Contactor breaker.
Operation: Control & Switching.
IEC60947-6-2
AC 42Load Type: Slip-ring motor.
Switchgear: CPS-Control and protective switching devices, eg. Integral Contactor breaker.
Operation: Control & Switching.
Operation: Switching off.
IEC60947-6-2
AC 43Load Type: Squirrel cage motors.
Switchgear: CPS-Control and protective switching devices, eg. Integral Contactor breaker.
Operation: Starting, Switching off during running.
IEC60947-6-2
AC 44Load Type: Squirrel cage motors.
Switchgear: CPS-Control and protective switching devices, eg. Integral Contactor breaker.
Operation: Starting, Plugging, Inching.
IEC60947-6-2
AC 45ALoad Type: Electric discharge lamp.
Switchgear: CPS-Control and protective switching devices, eg. Integral Contactor breaker.
Operation: Control & Switching.
IEC60947-6-2
AC 45BLoad Type: Incandescent
Switchgear: CPS-Control and protective switching devices, eg. Integral Contactor breaker.
Operation: Control & Switching.
IEC60947-6-2
AC 51ALoad Type: Non Inductive or Slightly inductive loads.
Switchgear: AC semiconductor motor controllers and starters, eg. Soft Starter.
Operation: Switching.
IEC60947-4-2
AC 51BLoad Type: Non Inductive or Slightly inductive loads.
Switchgear: AC semiconductor motor controllers and starters, eg. Soft Starter.
Operation: Switching.
IEC60947-4-2
AC 52ALoad Type: Slip ring motor.
Switchgear: AC semiconductor motor controllers and starters, eg. Soft Starter.
Operation: Control of slip ring motor stators for 8 hour duty with on load current for start, acceleration & run.
IEC60947-4-2
AC 52BLoad Type: Slip ring motor.
Switchgear: AC semiconductor motor controllers and starters, eg. Soft Starter.
Operation: Bypassed during motor running.
IEC60947-4-2
AC 53ALoad Type: Control of squirrel cage Induction motor on 8 hour duty with on load current
for start, acceleration and run.
Switchgear: AC semiconductor motor controllers and starters, eg. Soft Starter.
Operation: Soft-Starter Control. These Soft starters are not bypassed during motor running.
IEC60947-4-2
AC 53BLoad Type: Control of squirrel cage induction motors on intermittent duty.
Switchgear: AC semiconductor motor controllers and starters, eg. Soft Starter.
Operation: Soft-Starter Control. These Soft starters are bypassed during motor running.
IEC60947-4-2
AC 55ALoad Type: Electric Discharge lamp.
Switchgear: AC semiconductor controllers and contactors for non-motor loads, eg. IGBT.
Operation: Switching.
IEC60947-4-3
AC 55BLoad Type: Incandescent
Switchgear: AC semiconductor controllers and contactors for non-motor loads, eg. IGBT.
Operation: Switching.
IEC60947-4-3
AC 56ALoad Type: Transformer.
Switchgear: AC semiconductor controllers and contactors for non-motor loads, eg. IGBT.
Operation: Switching.
IEC60947-4-3
AC 56BLoad Type: Capacitor bank.
Switchgear: AC semiconductor controllers and contactors for non-motor loads, eg. IGBT.
Operation: Switching.
IEC60947-4-3
AC 58ALoad Type: Hermetic refrigerant compressor motor with automatic resetting of overload releases.
Switchgear: AC semiconductor motor controllers and starters, eg. Soft Starter.
Operation: Control for 8 hour duty with on load current for start, acceleration & run.
IEC60947-4-2
AC 58BLoad Type: Hermetic refrigerant compressor motor with automatic resetting of overload releases.
Switchgear: AC semiconductor motor controllers and starters, eg. Soft Starter.
Operation: Start of Motor, then bypassed during motor running.
IEC60947-4-2
AC 140Load Type: Small electromagnetic loads with holding (closed) current 0.2A or less.
Switchgear: Control circuitdevices and switching elements – Proximity switches, eg. contactor relays
Operation: Switching.
IEC60947-5-2
AC Utilization Categories IEC 60947
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