Leakage sensors are used in the stator housing or junction box to detect liquid. Because of its design, it is best suited for vertical pumps/mixers.
Construction of leakage detector:
The detector is enclosed in an aluminium frame. A mobile float element, guided by a shaft, can move up and down inside the frame. In the frame surrounded by a polyurethane filler, two resistors and a reed contact are built. Two permanent magnets are on top of the float element.
The element raises to the top position in case of leakage and the proximity of two magnets closes the reed contact.
- The normal or safe condition resistance reading or values of the unit is in the 1500 Ohms range. At this point the switch contacts are open.
- The leak or fail condition resistance reading or values of the unit is in the 300 Ohms range. At this point the switch contacts are closed.
- Overheated motor or failed thermal sensor will result in an open circuit.
The leakage is installed in at the bottom of the stator housing, on the top of bearing holder, bonded to it with an epoxy-based adhesive. The sensor is located in the lower position of the stator housing for use in mixers. The angle of the mixer should not exceed 30 ° for correct function.
Leakage alarm connection that can stop the pump:
The FLS is detecting liquid in the stator housing, which is critical and requires a quick stop of the pump.