Level controller for conductive liquids
The Omron 61F-G2ND AC110/220 is a High/Low Level controller from the 61F series, designed for conductive liquid level detection in tanks, reservoirs, and process vessels. It operates on a 110/220VAC supply and uses relay outputs (two relays) to signal alarm or control fill/drain cycles. The sensitivity range of 0 ~ 1.8kOhm means it can detect liquids with varying conductivity — from relatively pure water down to more conductive process fluids — by adjusting the threshold via the front-panel trimmer. The 1km maximum distance between controller and sensor electrodes gives flexibility for remote tank farms or elevated vessels where the electronics need to be away from the wet area.
Contact ratings and wiring
Each SPDT relay is rated 3A @ 200VAC, adequate for pilot duty on contactors, solenoid valves, or alarm panels. Two Form C contacts (SPDT each) give independent N.O. and N.C. poles — one set can drive a pump-up circuit, the other a high-level alarm, without external interposing relays.