Theory of operation – Grain Systems PNEG-728 User Manual
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Autoflow Operation
THEORY OF OPERATION
Top Dry Autoflow Theory of Operation
Control Panel Switches Status:
Control Power:
On
24v Power:
On
Moisture Control Thermostat:
On
Aeration Fan:
Auto
Load Auger:
Auto
Fan:
Auto
Heater:
Auto
Dump:
Auto
Dry & Hold:
Off
Emergency Stop Switches Status
Autoflow Control Box Emergency Stop: pulled out
Fill System Control Box Emergency Stop: pulled out
Actuator Control Box Emergency Stop: pulled out
Aeration Fan Bypass: Continuos
When the Top Dry is in a ready state; that
is, with no grain the Drying Chamber and wet
grain in the Wet Storage Tank, Fill System #1 and
Fill System #2 will start to fill the Drying Chamber
with wet grain when the start switch is pressed on
the Dryer Control Panel. In single fill system
units on Fill System #1 will start. When grain
reaches the Drying Chamber Low Level Rotary
Switch the Aeration Fan, and the Master Drying
Fan will come on, and the Fan Delay will start to
count down. When the Fan Delay reaches zero the
Slave Drying Fan will start, the Airswitch will
close, and the Dry Timer will start to count down.
In single fan units the Fan Delay will not count
down and the Airswitch will close after the Master
Drying Fan starts. After a twenty second Purge
Delay the fan/heater unit(s) will ignite. When the
Plenum Temperature reaches the Cycle Setpoint on
the Hi-Lo Thermostat the fan/heater unit(s) will
cycle to Low-Fire. When the Plenum Temperature
falls ten degrees below the Cycle Setpoint the fan/
heater unit(s) will cycle back to High-Fire. The
fan/heater unit(s) will continue to cycle throughout
the drying.
When grain reaches the Chamber High
Level Rotary Switch the Load Delay will begin to
count down. When the Load Delay reaches zero
Fill System #2 will shut off and the Aux. 1 Delay
will begin to count down. When the Aux. 1 Delay
reaches zero Fill System #1 will shut off.
If the Chamber High Level Rotary Switch
becomes exposed due to shrinkage of grain in the
Drying Chamber, the fill system(s) will start and
refill the Drying Chamber. When grain reaches
the Chamber High Level Rotary Switch the fill
system(s) will shut off after the delays.
When the Dry Timer reaches zero and the
Grain Temperature Setpoint on the Moisture
Control Thermostat has not been reached the unit
will go into Temperature Hold. When the grain
temperature reaches the Grain Temperature
Setpoint on the Moisture Control Thermostat the
unit will continue to the Dump Cycle. In the
Dump Cycle the Linear Actuator in the Actuator
Control Box extends, the dump chutes lower, and
grain is dumped from the Drying Chamber into
Storage Chamber. Immediately after the dump
chutes open the Unload Timer begins to count
down. When the Unload Timer reaches zero the
dump chutes raise and grain stops dumping from
the Drying Chamber into the Storage Chamber.
During the Dump Cycle, 1/3 of the grain is
dumped into the Storage Chamber.