Grain Systems PNEG-728 - Manual (Page 38)

Autoflow Operation
38
Drying Chamber Overflow Rotary Switch-The
drying chamber overflow rotary switch is one of
three rotary switches located in the drying cham-
ber. The drying chamber overflow rotary switch
has the shortest shaft of the three drying chamber
rotary switches. The drying chamber overflow
rotary switch warns the computer when grain is
getting too high in the drying chamber.
Dump Cycle-On Autoflow units the dump cycle is
the cycle entered into after completion of the dry
cycle. The dryer will not enter into the dump cycle
until both the dry timer has reached zero and the
grain temperature has reached the grain tempera-
ture setpoint set on the moisture control thermo-
stat. If the moisture control thermostat switch is
placed in the “off” position the dryer will ignore
the grain temperature setpoint. On Autobatch
units the dump cycle is entered into after the cool
cycle.
Fan Delay-The fan delay is not used in single fan
units. In two fan units it is the delay between the
starting of the master drying fan and the starting of
the slave drying fan. The fan delay is used to
prevent the excessive current draw experienced
when two large fan motors start at the same time.
The fan delay is programmed into the computer by
the user in the set-up mode detailed later.
Fill System #1-Fill system #1 is the fill system
that is controlled by the Autoflow and loads wet
grain directly into the drying chamber. Fill system
#1 is always present in an Autoflow system. The
motor starter for fill system #1 is located in the Fill
System Control Box.
Fill System #2-Fill system #2 is the fill system
that is controlled by the Autoflow and loads grain
into fill system #1. Fill system #2 shuts down in
normal operation before fill system #1 to allow fill
system #1 to clean out before it shuts off. Fill
system #2 is not required for proper operation of
the Autoflow unit; however, the computer must be
TERMINOLOGY
instructed on the number of fill systems the unit
has. This is done in the set-up mode detailed later.
The motor starter for fill system #2 is located in
the Fill System Control Box.
Fill System Control Box-The fill system control
box houses the motor starters for the fill system(s)
and the aeration fan. The fill system control box
also has start and stop switches which can operate
the fill system(s) and aeration fan manually when
the dryer is not running. The fill system control
box is mounted on the bin sidewall.
Grain Temperature Setpoint-On Autoflow units
the grain temperature setpoint is the temperature
that the grain must reach before the dryer will
continue from the dry cycle to the dump cycle. On
Autobatch units the grain temperature setpoint is
the temperature that the grain must reach before
the dryer will continue to the cool cycle. The grain
temperature setpoint is set at the moisture control
thermostat on the dryer control panel.
High-Fire-High fire is the state the burner is in
when the plenum temperature is below the cycle
setpoint set on the hi-lo thermostat. When the unit
is in high-fire the plenum temperature should be
on an upward climb. When the unit is in high-fire
the gas pressures should be set around 15 lbs. for
liquid propane units and 6 lbs. for natural gas
units. The gas pressures required to obtain the
desired temperature rise may vary with ambient air
conditions.
Hi-Lo Thermostat-The hi-lo thermostat is used
by the unit to monitor the current plenum tempera-
ture. The cycle setpoint is set on the hi-lo thermo-
stat. The hi-lo thermostat is also responsible for
monitoring the plenum high limit detailed later.
The hi-lo thermostat is attached to the master
drying fan and is mounted on the bin sidewall even
with the master drying fan. In two fan units do not
mount the hi-lo thermostat between the master and
slave fan and heater units.