Filtration Learning System
Setup
© Festo Didactic
696684
29
8.7
Pump
Centrifugal pumps are used to convey the liquid.
One wastewater pump delivers the liquid through
the filter, the second pump delivers the liquid
during backwashing through the filter or to
downstream stations.
The centrifugal pump must not run dry. For this
reason, the tank or piping to and from the pump
must be filled with liquid before commissioning.
Figure 10: Pump with 24 VDC motor
In both cases, the motors of the pumps are actuated via a switching relay with 2-way changeover contacts.
The motors are binary-controlled (on/off) with a digital output (at the I/O terminal XD1).
The pumps must not be operated dry. To connect the pumps, please refer to the electrical circuit diagram.
8.8
3-way ball valve unit
1
3
4
5
2
A 3-way ball valve is mounted at the outlet of the
process water tank. In each case, two paths of the
valve are set to throughput by a pneumatic quarter-
turn actuator. Thus, the liquid can be pumped once
to the downstream station and once back to the
filter. The control unit consists of a 3W ball valve (3)
with L-bore, quarter-turn actuator (4), a flange-
mounted NAMUR pilot valve (1) with solenoid coil
(2) and sensor box (5).
The sensor box is used for electro-mechanical
position feedback to the control and regulating
equipment as well as for visual display for the
operator.
Figure 11: 3W ball valve unit (similar to figure)
