AC-1: Non-inductive or slightly inductive loads, resistance furnaces NAC-3: Normal AC induction motors: starting, switch off during running AC-4: Normal AC induction motors: starting, plugging, reversing, inching
Also suitable for motors with efficiency class IE3. IE3-ready devices are identified by the logo on their packaging.
Squirrel-cage motor Operating characteristics Starting:from rest Stopping:after attaining full running speed Electrical characteristics Make: up to 6 x rated motor current Break: up to 1 x rated motor current Utilization category 100 % AC-3 Typical applications Compressors Lifts Mixers Pumps Escalators Agitators Fans Conveyor belts Centrifuges Hinged flaps Bucket-elevators Air conditioning system General drives in manufacturing and processing machines
Extreme switching duty Squirrel-cage motor Operating characteristics Inching, plugging, reversing Electrical characteristics Make: up to 6 x rated motor current Break: up to 6 x rated motor current Utilization category 100 % AC-4 Typical applications Printing presses Wire-drawing machines Centrifuges Special drives for manufacturing and processing machines
Switching duty for non-motor loads, 3-pole, 4-pole Operating characteristics Non-inductive or slightly inductive loads Electrical characteristics Make: 1 x rated current Break: 1 x rated current Utilization category 100 % AC-1 Typical applications Electric heat
Short-time loading, 3-pole Time interval between two loading cycles: 15 minutes