- SR Single contact, right set point, for actuation on increasing or decreasing pressure
- OLS OEM Model, less relay and transformer components and housing but including infared diodes and phototransistor(s), light shutter and set pointer(s). For single or double contact
- RMR Remote-Mounted Relay, relay pack may be mounted remotely from gage. Standard length is 5 ft. For other lengths, specify cable length required
- TAMP Tamper-proof knobs, low temperature option, special scales, voltages and other features and modifications are available
- Special Housings available include Weatherproof (NEMA 4) and Explosion-proof (NEMA 7 & 9; NEC Cl I, Gr C&D; Cl II, Gr E, F&G; Cl III)
- Scale No. 3401 Square Root Specify Range
- Scale No. 3402 Blank Scale Specify Range
- Range .25-0-.25" w.c.
High & Low Latching Circuits. Dwyer Photohelic® switch/gages can be wired for high-latching, low-latching or combination high-low latching circuits. That is, the equipment will hold in these respective positions once activated and until manually reset. This can be particularly useful for alarm and signal applications where control is accomplished by another Photohelic® switch/gage or other means. Complete wiring and operational instructions are included. Where manual reset is required a dry circuit push button such as Dwyer Part A-601 should be used.