SPX HPD Series, Инструкция по эксплуатации

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Next, Purge Supply Valve E and Right Tower Purge
Exhaust Valve D are opened, and the Heater is
turned on. The Venturi Blower Intake Shutoff Valve
F is opened. Purge air passes through the venturi
blower, drawing in ambient air, augmenting the purge
air flow before passing through the heater. The
heated purge air then flows through the Right Purge
Check Valve, down through the right tower, and exits
through the Right Tower Purge Exhaust Valve D . The
Heater operates until the bed temperature sensor
signals heating is complete. Venturi Blower Intake
Shutoff Valve F closes, dry purge flow provides par -
tial cooling while recovering heat to drive additional
moisture from the bed.
Finally, the Right Tower Purge Exhaust Valve
D
is
closed. The right tower slowly repressurizes to full
line pressure and is ready to go back on-line.
2. Right Tower Drying – Left Tower Regenerating
At the start of the Right Tower Drying cycle, Right Inlet
Valve B opens, Left Inlet Valve A closes to isolate the
two towers. Wet, compressed air flows up through
the right tower where it is dried. The dry air exits the
dryer through the Right Outlet Check Valve.
Next, the Purge Supply Valve E is closed and the Left
Purge Exhaust Valve is opened. The left tower is
slowly depressurized through an exhaust muffler.
Next, Purge Supply Valve E and Left Tower Purge
Exhaust Valve are opened, and the Heater is turned
on. The Venturi Blower Intake Shutoff Valve F is
opened. Purge air passes through the venturi blower,
drawing in ambient air, augmenting the purge air flow
before passing through the heater. The heated purge
air then flows through the Right Purge Check Valve,
down through the right tower, and exits through the
Right Tower Purge Exhaust Valve D . The Heater
operates until the bed temperature sensor signals
heating is complete. Venturi Blower Intake Shutoff
Valve F closes, dry purge flow provides partial cool -
ing while recovering heat to drive additional moisture
from the bed.
Finally, the Left Tower Purge Exhaust Valve is closed.
The left tower slowly repressurizes to full line pres-
sure and is ready to go back on-line.
Figure 6 shows the air sampling system for the de-
mand cycle (Energy Management System – EMS)
option. A 3-way pilot valve directs an air sample
from the drying tower to the EMS sensor. The EMS
sensor detects the relative humidity and temperature
of the air sample. The air sample then exhausts to
atmosphere. The drying tower remains on-line until
the moisture front arrives at the sensor.
P
EMS
LEFT
TOWER
RIGHT
TOWER
Figure 6
Optional Moisture Sensing
Energy Management System (EMS)
Figure 4
Fixed Cycle Operation
Left Chamber Drying – Right Chamber Regenerating
Figure 5
Demand Cycle Operation with Venturi Blower
Left Chamber Drying – Right Chamber Regenerating