Dwyer Instruments Inc.’s Series AT23000MR and AT23000MRS ATEX-approved Photohelic switches/gauges combine the functions of a precise, highly repeatable differential-pressure switch with a large, easy-to-read analog pressure gauge. Gauge reading is unaffected by switch operation and will indicate accurately even if power is interrupted. The AT23000MR Series employ versatile electromechanical relays with low amperage ratings, which are a good fit for dry circuits. The AT23000MRS models with SPST (NO) solid-state relays are for applications requiring high-cycle rates. Easy-to-adjust set point indicators are controlled by knobs located on the gauge face (accessible opening case after de-energizing instrument). All models provide both low- and high-limit control. Compatible with air and other non-combustible, non-corrosive gases, they can be used in systems with pressures to 25 PSIG (1.725 bar). Optional construction is available for use to either 35 PSIG (2.42 bar) or 80 PSIG (5.51 bar) as well as an over-pressure relief valve. Flame-proof ATEX enclosures are available with glass window, which allows for viewing of set point needles and process pressure. – dwyer-inst.com