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.
| DC Category | Typical Application | Switchgear Standard |
|---|---|---|
| DC 1 | Load Type: Non Inductive or Slightly inductive loads, eg: resistance furnace Switchgear: Electromechanical contactors. Operation: Switching. | IEC60947-4-1 |
| DC 3 | Load Type: Shunt motors. Switchgear: Electromechanical contactors. Operation: starting, plugging, inching, dynamic breaking of motors | IEC60947-4-1 |
| DC 5 | Load Type: Series motors. Switchgear: Electromechanical contactors. Operation: starting, plugging, inching, dynamic breaking of motors | IEC60947-4-1 |
| DC 6 | Load Type: Incandescent lamps Switchgear: Electromechanical contactors. Operation: Switching | IEC60947-4-1 |
| DC 12 | Load Type: Resistive and solid state loads with optocoupler isolation Switchgear: Electromechanical control circuit devices, eg. Aux Contacts. Operation: Control | IEC60947-5-1 |
| DC 13 | Load Type: DC Electromagnets Switchgear: Electromechanical control circuit devices, eg. Aux Contacts. Operation: Control | IEC60947-5-1 |
| DC 14 | Load Type: DC Electromagnet load with economy resistor Switchgear: Electromechanical control circuit devices, eg. Aux Contacts. Operation: Control | IEC60947-5-1 |
| DC 20A | Load Type: Connecting / Disconnecting under no load condition Switchgear: Electromechanical control circuit devices, eg. Aux Contacts. Operation: Connecting / Disconnecting. Frequent operation. | IEC60947-3 |
| DC 20B | Load Type: Connecting / Disconnecting under no load condition Switchgear: Electromechanical control circuit devices, eg. Aux Contacts. Operation: Connecting / Disconnecting. Infrequent operation. | IEC60947-3 |
| DC 21A | Load Type: Switching of resistive loads, with moderate overload Switchgear: Switches, disconnectors, switch-disconnectors. Operation: Switching. Frequent operation. | IEC60947-3 |
| DC 21B | Load Type: Switching of resistive loads, with moderate overload Switchgear: Switches, disconnectors, switch-disconnectors. Operation: Switching. Infrequent operation. | IEC60947-3 |
| DC 22A | Load Type: Switching of mixed resistive and inductive loads, with moderate overload, eg. shunt motors. Switchgear: Switches, disconnectors, switch-disconnectors. Operation: Switching. Frequent operation. | IEC60947-3 |
| DC 22B | Load Type: Switching of mixed resistive and inductive loads, with moderate overload, eg. shunt motors. Switchgear: Switches, disconnectors, switch-disconnectors. Operation: Switching. Infrequent operation. | IEC60947-3 |
| DC 23A | Load Type: Switching of highly inductive load, eg. series motors Switchgear: Switches, disconnectors, switch-disconnectors. Operation: Switching. Frequent operation. | IEC60947-3 |
| DC 23B | Load Type: Switching of highly inductive load, eg. series motors Switchgear: Switches, disconnectors, switch-disconnectors. Operation: Switching. Infrequent operation. | IEC60947-3 |