AEC Continuous Vacuum/Pressure Conveying Systems - Manual (Page 47)

Page 46 Single- and Dual-Blower Continuous Vacuum/Pressure Systems
IMPORTANT! Do not attempt to adjust the relief valve
to more than 1 psig (about 7 kPa/70 millibars)
above the maximum operating pressure
for your system (typically 7 psig or about 48.265 kPa/0.482
bars).
Doing so voids your pressure pump warranty!
Vacuum Vent Valve
SVP Pumps Only
When the purge button is pressed, the solenoid valve on the vent valve
energizes and the cylinder opens to draw vacuum from the atmosphere instead
of from the vacuum line. The vent valve breaks the vacuum, but supplies air to
purge material on the pressure side of the material line.
Vacuum On Delay Timer
1TR
Set the Vacuum On delay timer. It controls how long the vacuum blower is in
the idle state (SVP systems) or in the shutoff mode (CVP/CPP systems) before
resuming normal convey cycle. Set it so material can clear from the cyclone
separator or filter receiver before it is conveyed again. Timer range is zero to ten
(0-10) seconds.
Auto Shutdown Timer or Purge Timer
Set this timer to control how long the pressure unit continues to operate after
you press Purge Stop (3PB). Allow the unit to run long enough to empty the
cyclone/filter receiver, blow-through adapter, and the entire pressure side
material line.
If material is left in the pressure line when the system is shut down, it tends to
plug the line when you restart the system. When adjusting this time to your
application, start with the timer at the maximum setting and work back to the
optimum time. Turn it clockwise to increase the setting. When the timer times
out (zero to ten [0-10] seconds), the entire system shuts down. With SVP
systems, the pump goes into a vent cycle while it purges the pressure side of the
material line. In CVP/CPP systems, the vacuum pump shuts down while the
pressure motor runs for a preset time as determined by the purge timer.
Blowback Timer
Refer to the electrical schematic enclosed in the Customer Information Packet
for adjusting blowback on/off pulses and the duration of each pulse.