Complete Kit Includes:

Level Sensors and Temperature Sensors with 50 feet of Sensor Wire, Controller, and Mounting Assembly


    • 4-Contact point system with one temperature sensor
    • 10-wire Dry contacts to BAS for measuring:
      • Fill “ON” time
      • High Water Alarm
      • Low Water Alarm
      • Heater “ON”
      • Fault conditions
    • Operates any 110VAC valve & 110VAC audible alarm (Not supplied in this kit – see options section)


The WLC6100T Has Fill, High and Low Alarm controls, plus an imbedded heater control along with a low water cut off for the heater. The heater activates at 37°F and turns off at 48°F. The relay in the controls is a pilot relay for a 3-phase contactor to operate an emersion heater (both are available separately) so as to keep the water from freezing in the winter.

We have used these on Cooling tower basins, Holding tanks and other applications that are susceptible to freezing. The LED lights work differently on this controller, compared to other models in that when the heater is active the Heater On light is on. Whenever there is a low water condition and the low water cut off is activated. Because of that the LED lights pulse and the dry contacts pulse to signal the operator that there is a problem. It does not turn the heater pilot relay on during this sequence.


The heater control relay is designed to be a pilot relay for operating a 110VAC coil on a contactor properly sized for the heater. The temperature probe is built into the water level sensor and is to be mounted below the minimum water level of the tank (see the accompanying figure). It is also to be mounted at least 24 inches from the tank heater.

The system monitors for a high water level condition, a low water level condition and a Low-Low Level condition for Heater Cut-Off. This system also monitors the temperature of the water in the basin. These conditions have three outputs each which:

    1. Close a set of dry contacts for the BAS
    2. Operate a relay rated at 30AMPS / 250VAC
    3. Turn on an LED to indicate the sensor has tripped.
    4. Activate when the water falls to a lower set point than the low alarm.
      When this fourth set point activates it removes power from the Heater in the basin by opening a normally closed relay, closing a set of dry contacts and turning on a red LED. In addition, if the temperature of the basin water falls to 40 degrees F the Controller shall activate a relay to turn on the Basin heater. This system will not turn this relay off until the temperature reaches 51 degrees F or if the water falls below the Low-Low heater cut-off.

The Fill dry contacts can be used as a comparative to develop a baseline benchmark of water usage for the system.

*Custom Sensors lengths available upon request.

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All of our liquid level controls and liquid level sensors are assembled right here in the U.S.A.
where we monitor every step of the process.


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