SAF
– 4500
910101-000341 / 07.2019
Page 10 of 26
Initiation of self-cleaning:
The filter initiates the self-cleaning process under any one of the following conditions:
1. PD flush - The Pressure Differential Switch (PDS) closes a free potential contact signal when the pressure differential across
the screen reaches the pre-set value (usually 0.5 bar =7 psi). The control board registers the signal and activates the flushing
cycle.
2. Test flush - Manually pressing the "TEST" push button on the control board door activates a single flushing cycle.
3. Timed flush - SW1 must be in the DP/Time position. The T1 timer in the control panel activates the flushing cycles at time
intervals, regardless of the pressure differential. The timer resets after every flushing cycle. The PD flush mode is active in
this mode as well.
4. Continuous flush - SW1 must be in cont position. In this mode the filter flush continuously. This mode is for use in
extraordinary circumstances and for a limited time. Please consult with the manufacturer regarding the uses of this mode.
Control system:
Two types of control boards are available: PLC Type and Relay Type. See Appendix A or B for details.
