The Omron 61F-G2-AC100/200 is a conductive-type level controller from the 61F series, configured for high/low level detection — meaning it monitors two probe points to maintain a fill/drain cycle or trigger a high-level alarm. The 100/200VAC supply input lets it run off common line voltages without a separate control transformer. Sensitivity is adjustable from 0 to 4kOhm, which covers most water-based liquids (tap water, wastewater, dilute chemicals) but not deionized or distilled water where conductivity is too low. The two SPDT relays (one Form C per channel) each switch 5A at 220VAC, enough to drive a small pump contactor or alarm indicator directly.
Chassis-mount form factor — screws onto a backplate or inside a panel enclosure. Screw terminals for all connections: supply, probe electrodes, and relay outputs. The control-to-sensor distance rating of 1km means the sensing electrodes can be located at the tank while the controller sits in the electrical room, as long as the probe wiring stays within that loop resistance. Wiring practice: keep probe wires separate from power cables to avoid false triggering from coupled noise.