The Omron 61F-GP-ND-AC100 is a conductive level controller from the 61F series, a mature product line for liquid level detection in tanks, sumps, and process vessels. It operates on a 100VAC supply and uses a relay output (SPDT, 2 Form C) rated at 3A at 250VAC to switch pumps, valves, or alarms. The sensitivity range of 0 to 1.3kOhm means it detects the presence of conductive liquids (water, weak acids, coolants) by measuring resistance between the probe and a common electrode. The control-to-sensor distance of up to 1km allows the controller to be mounted in a panel remote from the tank.
The controller mounts via an 11-pin octal socket (plug-in termination style), which is typically DIN-rail or panel-mounted. The socketable form factor allows quick replacement without rewiring — useful for MRO spares or panel retrofits. The relay output is SPDT (2 Form C), giving one normally-open and one normally-closed contact pair for fail-safe wiring.