New, 4-20mA Transmitter Option for Hazardous Location Differential Pressure Switch

Mid West Instrument’s (USA) new Model 220 now provides a simple, low cost Loop Powered 828 VDC two wire 4-20mA Transmitter option using the same CSA, UL & ATEX rated sensor and explosion-proof housing used on their popular Model 220 with switches. The transmitter with an industrial type terminal strip is housed in heavy-duty, cast aluminum housing. Field wiring uis simple; access is through a ½” NPT port. Accuracy is ±2% from 20% to 100% of full scale. Indicator accuracy is ±2% and is independent of the transmitter.

The new Model 220 piston operated unit has pressure containing elements of aluminum or 316 S.S. with 316 S.S. and ceramic terminals. Safe working pressure is 4000 PSIG (275 bar) The new Model 220 has full over-range protection up to full rated working pressures. Differential ranges are available from 0-5 PSID to 0-100 PSID (0.3 bar to 7 bar). Weatherproof construction includes standard 4 ½” dial and shatter resistant lens – the instrument also has corrosion resistant gauge fronts. The unit, which comes with a 5 year warranty, is not yet listed for use in hazardous conditions (at time of publication December 2010).