The Omron 61F-GP-NH3 AC100 is a High/Low Level controller from the 61F series, designed for conductive liquid level detection in tanks, sumps, and process vessels. It operates on a 100VAC supply and detects level through probe resistance, with a sensitivity range of 0 to 200kOhm — adjustable to handle liquids from clean water to mildly conductive process fluids. The socketable design with an 11-pin octal base means it plugs into a standard relay socket for quick replacement without rewiring. Control distance to the sensor probes reaches up to 30m, giving flexibility for remote tank mounting relative to the control panel. Rated for an operating temperature range of -10°C to 55°C, it suits indoor panel environments where ambient stays within that band — typical for water treatment, cooling towers, and industrial sump monitoring.
The 0 to 200kOhm sensitivity adjustment is the critical setting for your liquid type. Clean water typically triggers at 10-50kOhm; oily or deionized water may need the full range. If your process fluid has conductivity outside this window, the controller won't detect level reliably. The 30m maximum distance between controller and sensor probes is a wiring limit, not a recommendation. Long probe cable runs add resistance and capacitance that can shift the effective sensitivity — keep the run under 30m and use shielded twisted-pair if the environment is electrically noisy. The 11-pin octal plug termination is the same footprint as many general-purpose relay sockets (e.g., Omron PYF-11 or equivalent). If your panel already has a socket wired for a different 11-pin device, verify the pinout matches before plugging this unit in — the level controller's probe and supply pins follow a specific arrangement.