Auxiliary contact ratings — voltage by voltage
The 3RT2023-1AU20: This means the same contact block handles both low-voltage PLC signals and higher-voltage control circuits — just match the voltage column to your control power.
Switching frequency by duty class
Maximum switching frequency is 1,000 operations per hour for AC-1, AC-2, AC-3, and AC-3e duty, dropping to 300 operations per hour for AC-4 duty — the heavier the load break, the fewer cycles per hour the contactor can handle. For a motor start-stop application running AC-3 duty, that's about one cycle every 3.6 seconds continuous; for AC-4 inching or plugging, you need to space cycles out to every 12 seconds.
Sourced through independent distribution channels; quoted to order against your BOM quantity.