Festo MPS PA, Operating Instructions Manual

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Setup Bottling Learning System
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© Festo Didactic 696690
8.5.1 Capacitive proximity sensors
Two capacitive proximity switches are mounted on a profile rail at the side of the main tank for monitoring
the water level with holding brackets. The proximity sensors can be adjusted mechanically on the mounting
rail. The lower proximity sensor indicates that the tank is filled with the minimum filling quantity of 2 liters.
The upper proximity sensor indicates the maximum filling level (6 l) of the main tank. In the initial position,
that is, with the tank full, both proximity sensors are actuated.
8.5.2 Float switch
The float switches for installation in the cover and for side installation monitor the increasing liquid level in
the tank and serve as overflow protection. As soon as the maximum level is exceeded, the float moves
upward with both switches, the reed contact in the switch housing opens and interrupts the circuit of the
pumps. The pumps are switched off.
Figure 7: level monitoring with float switch (lateral installation)
8.5.3 Ultrasonic sensor
The ultrasonic sensor measures the level in the dosing tank and is adjusted in such a way that it supplies a
small voltage at a low level and a larger voltage at a higher level (inverted characteristic curve, 0...10 V).
Figure 8: Analog ultrasonic sensor