Datasheet and user manual :
https://www.finglai.com/att/comp/fl-en/relays/floatless-level-relays/C61F-GP/C61F-GP.pdf?srsltid=AfmBOorsTeowGWL56BomH6Zk_QfAOfxi34DHtW9yPcdhQe-UXqAhzcsrDescription:
The C61F-GP Floatless Level Switch is a reliable electrode-type liquid level controller designed for automatic control of water supply and drainage. It provides dependable level detection without the need for a mechanical float and is ideal for tanks, wells, and process applications.
Key Features:
Supply Voltage: 220 VAC
Secondary Voltage: 8 VAC for probe circuit
Contact Rating: 5 A @ 250 VAC (resistive load)
Operation Mode: Water supply or drainage selectable
Electrode Inputs: E1, E2, E3 terminals for water level probes
Mounting: 8-pin octal base (same as Omron MY relay socket)
Indication: LED status for Water Supply / Drainage
Brand: CKC Electric Co., Ltd (Taiwan)
Applications:
Automatic tank filling and emptying
Industrial water treatment systems
Cooling tower and boiler level monitoring
General liquid level control systems
Included in Box:
1 × ST 61F-GP Floatless Level Switch
1x din mount octal base