Dwyer Sales Department: 1-201-419-6111 ext. 26 for Sales Group  |  dwyer@nciweb.com


Dwyer Series A1 Low Cost OEM Pressure Switch

316 SS Diaphragm. Optional Weatherproof Enclosure. Ranges from 3-20 to 50-500 psig
Low Cost and Precision Made, The A1 Pressure Switch is ideal for panel mounting wherever a high quality, economical open case control is required. Perfect for a wide range of applications in industrial service, the compact Series A1 control is available with field adjustable operating ranges from as low as 2-20 psig up to 50-500 psig (14-140 kPa to 345-3450 kPa). A convenient indicating scale is included, allowing quick and easy field adjustment of the actuation point. The rugged A1 construction incorporates the feature most often requested by customers; a 316 stainless steel diaphragm pressure element for exceptional compatibility and long service life. Standard pressure chamber is aluminum with a Teflon® impregnated hard coating, perfect for oil based hydraulic fluids and non-corrosive air and gases. Choose optional brass chamber for water and water-based fluids or 316 stainless steel for harsher applications. Optional weatherproof housing meets NEMA 4X standards.
click image to enlarge
Chemical petroleum, food and drug processing industries. Used indoor, outdoor or in explosion-proof area.
  • Maximum Pressure: 750 psig (5171 kPa)
  • Temperature Limits: -40 to 180°F (-40 to 82°C)
  • Mounting and Process
  • Connections: 1/8" NPTF x 1/2" NPTM
  • Switch Type: SPDT snap action
  • Electrical Connections: 3 screw terminals
  • Electrical Ratings: 15 A @ 120/240/480 VAC,
  • 1/8 HP @ 125 VAC, 1/4 HP @ 250 VAC
  • Setpoint Adjustment: Knurled screw cap (Deadband is fixed)
  • Chamber Material: Anodized aluminum std.
  • Optional; brass or 316SS
  • O-ring Material: Viton
  • Diaphragm: 316 stainless steel
  • Installation: Within 20° of vertical
  • Weight: 9 ounces (.25 kg)
  • Approvals: Recognized component under UL 508
-- MODELS NUMBERS (stock shown in bold)
Range, PSIG Range, kPa Deadband in psig (kPa) at min./max.
 A1S-O-AL-1-1  3-20  14-140  1/3 (7/21)
 A1S-O-AL-1-2  15-150  103-1030  5/15 (34/103)
 A1S-O-AL-1-3  25-250  172-1720  8/25 (55/172)
 A1S-O-AL-1-4  50-500  345-3450  15/50 (103/345)