Dwyer A3304 Offers

Features

• Bezel and front cover (with set point knobs and zero adjustment screw) removed to expose Photohelic® switch/gage set point mechanism (cover is clear polycarbonate plastic)
• Gauge 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% over or under voltage
• 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
• Unique design and 1% full scale dead band provides quick response to pressure changes means no delay in switching and chatter-free operation

• Air conditioner systems
• Clean rooms
• Fume exhaust systems