Specifications

Portable Drying/Conveying Systems Chapter 4: Operation 48 of 76
6. Once the control power is on and no fault conditions exist, turning the Off-On switch to the ON
position and pressing the START button on the touch screen will start the dryer as follows:
a. The process heater is turned on and controlled by the PLC.
b. The process/regen blower is started.
c. The regen heater is turned on and the regeneration timing sequence is initiated. The regen
heater is controlled by the PLC.
7. If either the left or right bed safety temperature switch opens, a REGEN TEM SAFETY is
generated. The alarm horn and light are activated. The process heater, regen heater, and process/regen
blower are turned off. Pressing the ALARM SILENCE button on the touch screen will deactivate the
alarm horn and light.
8. Turn the Off-On switch to the ON position and push the touch screen START button to restart the
dryer. If the switch is still open, the dryer will not restart.
9. If the PLC/touch screen faults, the optional redundant high temperature safety device opens, or the
process heater safety switch opens, a process heater fault is generated. The alarm horn and light are
activated. The process heater, regen heater, and process/regen blower are turned off. Pressing the
ALARM SILENCE pushbutton will deactivate the alarm horn and light.
3. Turn the Off-On switch to the ON position and push the START button to restart the dryer. If the
fault condition still exists, the dryer will not restart.
4. If the process blower overloads trips, a PROCESS BLOWER FAIL is generated. The alarm horn
and light are activated. The process heater, regen heater, and process/regen blower are turned off.
Pressing the ALARM SILENCE button will deactivate the alarm horn and light.
5. Reset the motor overload and turn the Off-On switch to the ON position and push the START
button on the touch screen to restart the dryer.
6. The valve position limit switch enables the right bed heater and provides an input signal to the PLC
when actuated by the cam lobe. Each heater is controlled by the PLC.
7. Upon completion of the HEAT portion of the regeneration sequence, the regen heaters are disabled
by the PLC and the COOL time begins.
8. Once the COOL time has expired, the valve motor is turned on until the cam switch makes a
transition. Upon making a transition, the timing sequence is restarted for the new bed.
9. When a HIGH DEW POINT alarm is generated by the dew point controller, the alarm horn and
light will activate. Press ALARM SILENCE to deactivate the alarm until the next HIGH DEW
POINT alarm occurs.
10. The dryer is shut off by pushing the SHUTDOWN button on the PLC or turning the control power
On/Off switch to the OFF position.
11. Refer to the schematic drawing enclosed in the control enclosure.