The AP 400 B420L from LEM is a Current Transducer with AC Input Current 200 to 400 A, Output Current 0.025 A, Supply Voltage 12 to 24 V, Accuracy 0.01, Frequency 0.03 to 2 kHz. Tags: Panel Mount, DIN Rail Mount, AC Current Transducer. More details for AP 400 B420L can be seen below.