IEC koblingsklasser
Current	Category	Typical Applications	Relevant IEC Product Standard (3)
A.C.	AC-1	Non Inductive or slightly inductive loads, resistance furnaces, heaters	60947-4
	AC-2	Slip-ring motors: switching off
	AC-3	Squirrel-cage motors: starting, switching off motors during running Most typical industrial application
	AC-4	Squirrel-cage motors: starting, plugging(1), inching (2)
	AC-5a	Switching of electric discharge lamps
	AC-5b	Switching of incandescent lamps
	AC-6a	Switching of transformers
	AC-6b	Switching of capacitor banks
	AC-7a	Slightly inductive loads in household appliances: mixers, blenders
	AC-7b	Motor-loads for household applications: fans, central vacuum
	AC-8a	Hermetic refrigerant compressor motor control with manual resetting overloads
	AC-8b	Hermetic refrigerant compressor motor control with automatic resetting overloads
	AC-12	Control of resistive loads and solid state loads with opto-coupler isolation	60947-5
	AC-13	Control of solid state loads with transformer isolation
	AC-14	Control of small electromagnetic loads
	AC-15	Control of A.C. electromagnetic loads	60947-3
	AC-20	Connecting and disconnecting under no-load conditions
	AC-21	Switching of resistive loads, including moderate loads
	AC-22	Switching of mixed resistive and inductive loads, including moderate overloads
	AC-23	Switching of motor loads or other highly inductive loads
A.C. and D.C	A	Protection of circuits, with no rated short-time withstand current	60947-2
	B	Protection of circuits, with a rated short-time withstand current
D.C	DC-1	Non Inductive or slightly inductive loads, resistance furnaces, heaters	60947-4
	DC-3	Shunt-motors, starting, plugging(1), inching(2), dynamic breaking of motors
	DC-5	Series-motors, starting, plugging(1), inching(2), dynamic breaking of motors
	DC-6	Switching of incandescent lamps
	DC-12	Control of resistive loads and solid state loads with opto-coupler isolation
	DC-13	Control of D.C. electromagnetics	60947-5
	DC-14	Control of D.C. electromagnetic loads having economy resistors in the circuit
	DC-20	Connecting and disconnecting under no-load conditions
	DC-21	Switching of resistive loads, including moderate overloads	60947-3
	DC-22	Switching of mixed resistive and inductive loads, including moderate overloads (i.e.shunt motors)
	DC-23	Switching of highly inductive loads (I.e. series motors)
	(1) Plugging - Stopping a motor rapidly by reversing the primary power connections. (2) Inching - Energizing a motor repeatedly for short periods to obtain small incremental movements. (3) IEC Standards must be purchased from the International Electrotechnical Commission