Tabla de contenido
Publicidad
AF900
DP FLUSH
A DP flush is caused by a differential pressure across the filter's system signal at DP
inlet for preset time (DP ON TM , Set by screen no. 1.0.2) will activates the DP FLUSH
mechanism. In this condition, absence of DP signal for preset time (DP OFF TM, set by
screen no. 1.0.3) deactivates the DP FLUSH Mechanism.
This internal ON/OFF delay timers assure that accidental DP switch vibrating will not
activates the flushing mechanism.
Once a DP flush signal is registered , the control unit will executes a REGULAR FLUSH
state as follows :
a. SV1 is activated. (First/one flushing valve open).
b. After preset time (Pre-flush time , Set by screen no. 1.0.1) the motor is activated
for a preset no. of scans as set DP REG. SCANS (Set by screen no. 1.1.3)
c. The DP signals is checked constantly
• If the DP signal is removed during the motor scan then the flushing cycle will finish
it's scan and motor and SV1 will be turned off .
• If the DP signal is continued after the first motor scan the motor will executes a
second scan and so on.
• If after x REGULAR FLUSH SCANS the DP signal is not removed then the control unit
will enter to EMERGENCY FLUSH state by turning on the SV2 solenoid (In addition to
SV1 , Both flushing valves opened) and for another x EMERGENCY FLUSH SCANS.
(Set by screen no. 1.1.4)
• If DP signal continues in spite of x regular flush and x more emergency flush scans,
which means that the flushing mechanism is unable to overcome the differential
pressure across the filter/s system then DP FLUSH FAULT state is declared (FAULT
Indicator lit.) and any further flush cycles is disabled.
• Pressing the FAULT sw. will reset the flushing mechanism and resume operation.
Example – 5 REG. FLUSH SCANS & 5 EME. FLUSH SCANS is set.
• If after 3 reg. flush scans the DP is removed then the system will return to normal
state.
• If after 5 reg. flush scans the DP is not removed then the system will continue with
EMERGENCY FLUSH scans.
• If after 2 emergency scan (7
normal State.
• If after the 10
th
scan the DP is not removed then the system will enter a DP flush
fault state.
th
scan) the DP is removed then the system will return to
39
Publicidad
Tabla de contenido
