Square D 9013FHG42J59X Air Compressor Pressure Switch

The Square D by Schneider Electric 9013FHG42J59X Pumptrol pressure switch is a DPST, electromechanical control for air compressors with an integrated unloader valve to vent the pump when the switch opens. It is factory-set for a 135 psi on-set and 175 psi off-set, delivering a fixed 40 psi differential, and features a 1/4 in NPSF internal port for piping. The unit includes a two‑way release/unloader valve and is part of the Square D Pumptrol family, designed for standard 1/4 in NPSF connections in air-compressor control systems. This switch is used to automatically start and stop a compressor to maintain target tank pressure while easing start-up and reducing motor stress during shut-off.