Dwyer, A3000 Series Photohelic Pressure Switch or Gage, 2-0-2 Inch w.c, DPDT, 1/8 Inch Female NPT A3304
3-in-1 Indicating Gage, Lo-limit and Hi-limit Control. The Series A3000 Photohelic Switch or Gages Function as Versatile, Highly Repeatable Pressure Switches Combined with a Precise Pressure Gage Employing the Time-Proven Magnehelic Gage Design. The Photohelic Switch or Gage Measures and Controls Positive, Negative or Differential Pressures of Air and Compatible Gases. Standard Models are Rated to 25 PSIG [1.7 Bar] with Options to 35 [2.4] or 80 [5.5 Bar] PSIG. Two Phototransistor Actuated, DPDT Relays are Included for Low or High Limit Control. Easy to Adjust Set Point Indicators are Controlled by Knobs Located on the Gage Face. Individual Set Point Deadband is One Pointer Width - Less Than 1 Percentage of Full Scale. Set Points can be Interlocked to Provide Variable Deadband - Ideal for Control of Fans, Dampers, etc. Gage Reading is Continuous and Unaffected by Switch Operation, Even During Loss of Electrical Power. Choose from Full Scale Pressure Ranges from a Low 0-.25 Inch [0-6 Millimeter] w.c up to 30 PSI [21 Bar].
Features & Benefits
Bezel and Front Cover [with Set Point Knobs and Zero Adjustment Screw] Removed to Expose Photohelic Switch or Gage Set Point Mechanism. Cover is Clear Polycarbonate Plastic
Gage Pointer and Light Shutter are Mounted on Helix and Balancing Counterweight. Shutter Passes Through Slot in Optical Limit Switch to Expose Phototransistors to Integral Infrared Light Source or Mask them Depending on Applied Pressure
Light Shield Effectively Protects Phototransistors from Strong Outside Light Sources Yet Allows Free Pointer Movement. It Also Gives Interior a Clean Finished Look
Optical Limit Switches are Used for Reliability and Long Service Life. Attached Directly to Set Pointers, They are Individually Aligned to Assure Precise Switching Accuracy
Semi-Flexible Drive Shaft Connects to Set Point Knobs, Zero Adjustment Screw Connects to Screw in Cover to Adjust Zero Pressure Reading
Plastic Enclosure Protects Electronic Components and Electrical Connections, Polycarbonate Connection or Terminal Board is Self-Extinguishing
Glass Epoxy Printed Circuit Boards for Durability and Permanence, Load Relays are DPDT with Latching Feature for Maximum Application Versatility
Electronics are Designed to Operate on 50/60 Hz, 120 Volt Current with 10 Percentage Over or Under Voltage. Special Units for Other Voltages are Available
Switch Set Pointers Show Switch Settings at All Times, Spring Loaded Friction Clutch Prevents Operator Damage of Set Point Mechanism
3-in-1 Instrument Allows the Reduction of Several Instruments with One Product, Saving Inventory, Installation Time and Money