Dwyer 685-00 is a differential pressure transmitter with a temperature range of -4 to 158°F. It offers accurate measurements of ≤ ±0.5% RSS (BFSL) with a response time of 1 s or 200 ms. The transmitter is enclosed in an IP54 rated housing and features a piezoresistive pressure sensor. It operates in humidity conditions of 0 to 95% RH and has electrical connections for cables and leads up to 1.5 mm². Output signals include 4-20 mA for 2-wire and 0-10 V for 3-wire configurations. The voltage ranges from 18-30 VDC for 2-wire and 18-30 VAC/DC for 3-wire. Mounting is achieved through screw fastening with sheet metal screws. The transmitter is suitable for air and non-corrosive gas service and is made of ABS material. Loop resistance is specified as ≤ 500 Ω for 2-wire and ≥ 1 kΩ (≤ 10 mA) for 3-wire configurations. It has a 6 mm hose connection and dimensions of Ø 66 x 28 mm. Stability is ≤ ±1% RSS per year and it comes with a 15 mm cap nut conduit made of polyamide for cable protection. Maximum current draw is 21 mA for 2-wire and 40 mA for 3-wire.