Phase sequence controller (RSF)
The RSF modules control the correct presence and sequence of the input phases L1, L2 and L3 and measure the three phase voltage. They are fitted with an output relay that is energised only when the sequence is correct and every single phase is ranging within ±10% of rated voltage (according to the model).
The devices features compact and modular dimensions (international DIN standard). Thus, their use is suggested for devices, systems or equipment where the correct phase sequence is indispensable for a good functioning.