Robertshaw Controls 167-A1 Capacitance Transmitter

The Robertshaw 167-A1 Capacitance Transmitter is a rugged RF capacitance-to-current transmitter that mounts directly on the sensing probe and provides a standard 4-20 mA DC output proportional to capacitance. It operates on a two-wire 17–35 VDC supply and drives a load of 0–1150 ohms, with an input capacitance range of 30–1000 pF and a maximum terminal capacitance of 2000 pF. This self-contained unit is housed in an explosion-proof, water-tight enclosure suitable for hazardous locations (CSA certified for Class I, Division 1, Groups C & D and Class II, Division 1, Groups E–G when wired per approved configuration) and can be mounted directly on Robertshaw probes such as models 702, 728, 729, 736, 738, 739, 740 or 741. The 167-A1 is the w/o-meter version (167-A2 includes a meter) and specifications include operation from −40°F to +160°F (−40°C to +71°C) and storage from −65°F to +200°F (−54°C to +93°C), with environmental limits of up to 95% RH at 100°F. This transmitter converts capacitance changes into a 4-20 mA signal for reliable remote indication and control in industrial level monitoring applications.