What this level controller does on your panel
The Omron 61F-G3NL AC110/220 2KM is a conductive-type high/low level controller that detects liquid level through two probe electrodes and a common reference. It switches its SPDT relay outputs when the liquid reaches the high or low set point — the alarm-high contact feature means one relay trips on the high level, giving you a separate alarm signal without extra logic. The 2 km maximum distance between the controller and the sensor head lets you mount the unit in a central panel while the probes sit at a remote tank or sump. Supply it with either 110 VAC or 220 VAC — the dual-voltage primary handles both without a jumper change. The sensitivity adjustment from 0 to 1.8 kΩ lets you tune the detection threshold for the conductivity of the liquid you are monitoring; lower resistance for clean water, higher for demineralized or process fluids.
DIN-rail fit and wiring constraints
The screw terminals accept up to 2.5 mm² stranded wire — strip 8 mm, torque to 0.5 N·m. Three SPDT relay outputs (two Form C) give you independent NO/NC contacts for pump control and alarm annunciation on the same unit. The 3 A at 200 VAC contact rating covers pilot-duty solenoid valves and indicator lamps; for direct motor loads, interpose a contactor.