The Omron 61F-G1ND AC110/120 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 110/120VAC supply and provides two SPDT (2 Form C) relay outputs rated at 3A @ 200VAC, giving you independent control for high and low alarm or pump start/stop logic. Sensitivity is adjustable from 0 to 1.8 kΩ, which means it can detect liquids with varying conductivity — from relatively pure water to more conductive process fluids — without false triggering on foam or residue. The control-to-sensor distance extends up to 1 km, so the controller can sit in a central panel while the probe is out at the tank. Mounts on standard DIN rail with screw-terminal wiring, making it a straightforward swap into an existing panel without re-terminating the field wiring.
The 3A @ 200VAC contact rating on the SPDT relays governs the load it can switch directly — small pumps, solenoid valves, or pilot relays. For larger motor loads, use the relay to drive an external contactor. The 1 km sensor distance is the maximum cable run between controller and probe; for runs over a few hundred meters, account for voltage drop in the sense wire, especially with lower-conductivity fluids. The Alarm Low - Contact and Idling Prevention features mean the controller can signal a low-level condition and prevent the pump from running dry — a common failure mode in sump and condensate applications.