Dehumidifying Dryers Chapter 4: Operation 34 of 59
4-3 Dryer Operation Procedures
Controller Operation (Without Optional Alarm Horn & Reset Button)
1. Turn the disconnect on the control panel to the ON position. Power is applied to the
voltage line fuses, line side of the control power switch and the temperature
controller.
2. Turn the control power switch to the ON position. Power is applied to the
programmable relay and dew point controller. The valve will move to the start
position as follows:
a. The valve motor rotates until the cam switch makes 2 transitions.
b. If the cam switch does not make a transition within 10 seconds, a valve
motor fault is generated. “VALVE MTR” is displayed on the relay screen,
the alarm light is activated. The valve motor, heaters, and blower shut off.
To restart the dryer, cycle control power to deactivate the alarm light and
restart the valve motor sequence.
Note: The relay screen which contains the Alarm Display Messages is located
inside the controller enclosure. For a list of Alarm Display Messages,
see Page 35.
WARNING! Do not attempt to check the Alarms on the Controller located within the
unit enclosure unless you are a qualified electrician!
c. The valve will normally complete one full cycle (revolution).
If the drying process shuts down due to an alarm, the dryer has been setup to
have the following operational features:
• The bed in process at power-down will remain in process.
• The bed in regeneration at power-down will remain in regeneration.
• The regeneration timing cycle will restart from the beginning.