Features 1、Adopt AC water measurement technology to effectively prevent probe scaling. 2、The water level sensor can detect and display 4 levels of water levels of 0%, 30%, 50%, 80%, 100%. 3、Manually fill the water to the full water level at any time, convenient to use. 4、5 Levels of full water level, 4 levels of replenishment water level adjustable. 5、One way normally open and normally close contact control water output, two way anti&#8209;dry contact output. Specification Condition: 100% Brand New Item Type: Liquid Level Switch Material: Plastic BF-KT4-AC is suitable for various water level control occasion, such as the roof water tank water level display and control of hotels and dormitory buildings, and the water tower water level display control. 4 levels of water level can be set to control the water tank filling, and the full water level and water replenishment can be set freely. The position value, with the function of water shortage and manual water filling, can control the water shortage of external equipment to prevent dry burning. Three-digit digital water volume percentage display, five-level water column, intuitive display of current water level. Switching power supply designs can make sure that the controller's power supply is still stable, reliable and continuous when it changes between AC80V-240V. Features: 1. Adopt AC water measurement technology to effectively prevent probe scaling 2. Water level sensor can detect and display 4 levels of water level of 0%, 30%, 50%, 80%, 100% 3. 5 levels of full water level, 4 levels of replenishment water level adjustable 4. One way normally open and normally close contact control water output, two way anti-dry contact output 5. Low water level is automatically filled to 50% water level 6. Manually fill the water to the full water level at any time 7. Water shortage prevents dry burning output 8. The flash memory can keep memory for a long time after power failure 9. Installation with waterproof silicone ring Technical Parameter Size: Approx. 58 x 78 x 85mm / 2.3 x 3.1 x 3.3in Installation and Size: Window installation, opening size is 51 x 71mm / 2 x 2.8in Working power and power consumption: working power AC80~240V, 3W, standby <2W Using Environment: Storage environment: -40℃~70℃; 5%-95% non-condensing Working Environment: 0℃~40℃: 10%-90% non-condensing Display mode and Resolution: LED three-digit number and column indicator display Keys: Push-type membrane keys Signal Input: One channel of liquid level resistance signal input (connected to M29 adapter box) Output and Power: One way normally open point water supply: 5A/250VAC, two way normally open point water shortage to prevent dry burning: 5A/250VAC Water Level Measurement Range: 0%, 30%, 50%, 80%, 100% Water Level Control Range: 30%, 50%, 80%, 100% Water Level Measurement Line Extension: The distance from the controller to the temperature and liquid level M29 junction box can be extended by 100 meters (not to be lined with the strong current common pipe) Parameter Memory: Using flash memory technology, set parameters can be maintained for a long time after power failure Package List 1 x AT35-7-U6 Water Level Sensor 1 x M29 Water Level Signal Line Switching Board 1 x Visual Liquid Level Switch 1 x Manual