• Differential pressure ranges: 6 to 150 inH2O
  • ±1.00% fs accuracy
  • Available pressure units: inH2O, mmH2O, kPa, mBar
  • High static pressure capability up to 1500 psi
  • Field-adjustable setpoint; fixed deadband
  • Rugged NEMA 4X aluminum enclosure
  • Watertight or explosion proof versions
  • Class 1, Div 1, Groups C & D, SPDT or DPDT setpoints
  • 1/4 NPT Female pressure connection


The Ascroft DDS Series differential pressure switch is designed to sense low differential pressures between high pressure sources. The high pressure seals are opposed stainless steel bellows assemblies, while the differential pressure is sensed by a diaphragm clamped between these bellows assemblies. The diaphragm has a large area to accurately sense low differential pressure, and during an over-pressure the diaphragm is fully supported. This DDS is ideally suited for pressure level sensing, filter monitoring, and pressure control.

The DDS design is symmetric so that both the high or low pressure sides of the element can withstand the maximum pressure with the opposite side at atmospheric pressure. The rugged cast aluminum housing incorporates a "frictionless" switching mechanism, and can be specified as watertight or explosion proof. The housing is large enough to accommodate up to one full size SPDT or one DPDT electric switches.

The standard differential pressure sensing element is constructed of a strong aluminum alloy using a Buna N elastomer diaphragm. Other diaphragm and wetted area materials are available.