The ITM-51 is located in the CIP return line before the drain valve. During the pre-rinse step of the CIP cycle the water returning from the cleaning loop is monitored by the ITM-51
. The ITM-51 produces an analog output proportional to the relative turbidity of the returning rinse water. An automatic control (PLC) acts upon the input based on a setpoint that represents the optimal turbidity for the pre-rinse to be complete. Once the signal from the ITM matches the setpoint the control closes the drain valve and advances to the wash step of the cleaning cycle.