Farm Fans C-2120A, Руководство оператора, Страница: 20 / 68

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able limits to the full load amperage listed in the
Electrical Specification Charts.
If fans start properly, turn the Upper and Lower Burner
switches to ON position. The burners should fire after
a short purge interval and gas pressure should be indi-
cated on the pressure gauge for each burner.
Adjust Upper and Lower Plenum Temperature
Controllers on the ASC panel to approximately 200°F
to cause both burners to operate on Hi-Fire. Observe
gas pressure indicated on each pressure gauge, then
turn plenum controllers down to their minimum setting
to cause burners to cycle into Lo-Fire. As the burner
controllers are turned down, each gas pressure gauge
should show a noticeable drop in pressure, indicating
the Hi-Fire gas solenoid valve has closed and the burn-
er is being supplied with only the reduced flow of gas
through the flow control valve and the Lo-Fire solenoid
valve.
NOTE: For additional information concerning the actu-
al recommended gas pressure settings and the adjust-
ment procedure, refer to Section 3 - OPERATING
CONTROLS.
The final gas pressure adjustments MUST be made
after dryer is filled with grain.
12. Check moisture control operation.
A. Set all switches to the positions shown in chart in
step 1.
B. Start the dryer control circuit, turn the Unload
Auger Switch to ON, and set the Meter Roll Selector
Switch to the MANUAL position. Adjust the UNLOAD-
ING RATE to 30%.
C. The Moisture Controller should be reading approx-
imately the same as ambient temperature unless there
is still residual heat in the dryer from previous burner
operation. Set the Moisture Controller to match the
measured temperature displayed. See Section 3 -
OPERATING CONTROLS for setting controller.
D. Set the Meter Roll Selector switch to AUTO, paus-
ing for a few seconds in the off position. The unloading
rate should begin at the previously adjusted manual
unloading rate.
E. Increase the Moisture Controller set point approx-
imately 30°F above the current measured temperature.
The Unloading Rate should drop to approximately 2/3
the manual unload rate, or 20%. Additional tempera-
ture increase will not cause further unload rate reduc-
tion.
F. Decrease the Moisture Controller set point approx-
imately 95°F below the measured temperature. The
unloading rate will increase to approximately twice the
manual unloading rate, or 60%.
G. Set the Meter Roll Selector Switch to MANUAL
position and reset the unload rate to 60%. Set the
Moisture Control back to match the displayed mea-
sured temperature. Again switch the Meter Roll
Selector Switch to AUTO, pausing in the OFF position.
Verify that the control starts at the manual unload rate.
Note that by decreasing the moisture control set point
temperature 95°F the unload rate will not exceed
100%.
13. Check safety shutdown devices.
A. Meter roll monitor
Start dryer control circuit and turn Unload Auger Switch
to ON, position Meter Roll Selector Switch to MANUAL,
and set Unload Rate to minimum setting. Allow unload
to operate for approximately (5) minutes. No shut down
should occur.
Set Unload Rate to 100% for at least 15 seconds then
position the Meter Roll Selector Switch to OFF. In
approximately (3) minutes, the dryer should shut down
and the meter roll monitor shutdown indicator will be lit.
B. Low grain monitor and fill switch
Adjust the Load Timer to a short time period of approx-
imately five minutes or less. Start the dryer control cir-
cuit and set the Load Auger Switch to ON. The Load
Timer should not be powered and no shut down should
occur after a five-minute or longer filling time.
If the physical setup of the grain drying system permits
safe access to the fill switch (also known as the paddle
switch), located on the wet bin, perform the following
test:
CAUTION: Use care to avoid falling and
causing personal injury.
While the load auger is running, slowly rotate the fill
switch box counterclockwise by hand until the load
auger stops. The load auger should stop when the
switch box is rotated to a position 50-55° from hori zon-
tal. Slowly rotate the box clockwise and the dryer
should restart at 15-20° before horizontal. Readjust fill
switch if required. See Fig. 4-1 for switch position dia-
gram.
Position the Load Auger Switch to AUTO. The Load
Timer should begin counting down and the dryer
should shut down after five minutes of loading. The
LOW GRAIN indicator light should be energized on the
control panel. Be sure to reset the Load Timer to the
appropriate time.
C. Discharge shut-off switch
Remove the shipping screw securing the hinged cover
on the discharge box if required. Check to see that the
cover works freely and seats tightly against the dis-
charge box approx. 1/4" from proximity switch.
Start the control circuit, turn the Unload Auger Switch to
ON, and Meter Roll Selector Switch to MANUAL. Lift
the cover on the discharge auger approximately one
inch. The dryer should immediately shut down; how-
ever, no monitor indicator will be energized.
14. Stop dryer operation.