for external installation outside the trench heater, 86 - 264 V AC, 24 V DC, 47 Hz, 92 W, on DIN rail, Protection class II Suitable for: EC units, electromechanical 24 V, max. number that can be connected 4 Katherm QK trench convectors7 Katherm QK nano trench convectors10 PowerKon nano convectors