[Ith] conventional free air thermal current
10 A (at 140 °F (60 °C)) for signalling circuit16 A (at 140 °F (60 °C)) for power circuit
Irms rated making capacity
250 A at 440 V for power circuit conforming to IEC 60947140 A AC for signalling circuit conforming to IEC 60947-5-1250 A DC for signalling circuit conforming to IEC 60947-5-1