1900 Compact Low Differential Pressure Switches

Advanced design, precision construction, compact size, and repeatability; with set points from 0.07 in W.C. to 20 in W.C.

Starting At
$65.00 CAD
Normally ships in 2-3 Weeks

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Our most popular Series 1900 combines advanced design and precision construction to make these switches able to perform many of the tasks of larger, costlier units. Designed for air conditioning service, they also serve many fluidics, refrigeration, oven and dryer applications. For air and non-combustible compatible gases, Series 1900 switches have set points from 0.07 in W.C. - 20 in W.C. (1.8 mm - 508 mm). Set point adjustment is easy with range screw located inside conduit enclosure. Internal location helps prevent tampering. UL, CE and CSA listed, and FM approved.

Caution: For use only with air or compatible gases.

• Compact size and repeatability, provides a high-value switch for many industrial and OEM applications
• Wide range of models from 0.07 in W.C. - 20 in W.C. can meet exacting OEM specifications for a low pressure switch
• Range screw protected inside enclosure provides simplifies making adjustments but prevents tampering


Service Air and non-combustible, compatible gases
Wetted Materials Consult factory
Temperature Limits -30F - 180F (-34C - 82.2C)
Pressure Limits 45 in W.C. (11.2 kPa) continuous, 10 PSIG (68.95 kPa) surge
Switch Type Single-pole double-throw (SPDT)
Repeatability 3%
Electrical Rating 15 A @ 120 VAC - 480 VAC, 60 Hz. Resistive 1/8 HP @ 125 VAC, 1/4 HP @ 250 VAC, 60 Hz. Derate to 10 A for operation at high cycle rates
Electrical Connections 3 screw type, common, normally open and normally closed
Process Connections 1/8 in female NPT
Mounting Orientation Diaphragm in vertical position. Consult factory for other position orientations
Set Point Adjustment Screw type inside conduit enclosure
Weight 1 lb 4.5 oz (581 g).
Agency Approvals CE, CSA, FM, UL. Optional EXPL Explosion-proof enclosure does not possess any agency approvals

• Air conditioning refrigeration coil icing detection; defrost cycle intiation
• Clogged filter detection
• Variable air volume controller

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