Differential pressure relay to detect overpressure, vacuum or differential pressure. It can be used for air or other non-combustible, non-agressive gases. The switching pressure setpoint can be adjusted by means of a scaled calibrated knob. This version detects differential pressure in the range of 20 to 200 Pa. The output contacts can switch a resistive load of max 1 A - 250 VAC. Delivered with PSET-PVC-200, a set of flexible transparent PVC tubes (length 2 m).