Grain Systems PNEG-1459 - Manual (Page 29)

29 PNEG-1459 L Series Operators
23. Once the moisture reading at the discharge is where you want it to be, turn the UNLOAD switch to AUTO.
24. Now that the UNLOAD AUGER switch is in the AUTO position the INTERMEDIATE MOISTURE CONTROL is active.
Now touch the M/C button at the bottom right of the Dryer Operation screen. When the Moisture Setpoint window appears set
the moisture setpoint to the output moisture you desire. Let the dryer run on these settings before trying to adjust moisture or
meter roll settings.
25. The dryer will immediately switch to the intermediate 3 speed moisture control. If you press the meter roll knob you will
now notice that there are three different meter roll speeds. The computer has automatically set the low and high speed setpoints
to 15% above and below the middle speed. The middle speed is the same as the manual speed that you had entered when staging
the grain for the correct exiting moisture content.
How the Intermediate Moisture Control Works
The controller continuously monitors the moisture coming in and out of the dryer, and the column grain temperature at the end
of the drying section. However, the control action is based on the dry sensor at the outlet of the dryer. If the moisture coming out
of the dryer is not right at the target, the controller will speed up or slow down the unload accordingly. How the meter rolls react
depends on the setpoint and the actual moisture coming out of the dryer. So long as the outgoing moisture is 3 tenths above or
below the setpoint, the meter rolls run on the middle speed. Once the moisture begins to drift from the setpoint by over 3 tenths
above or below the setpoint, the speed will automatically switch between middle and low, or middle and high speed. This is a
very fast response and will bring grain back towards the set point quickly.
The controller does not have enough information of the grain in the dryer in the first pass after the dryer is started. It controls the
dryer by using the manual speed setting as the starting point. In other words, the manual speed setting is most responsible for the
first pass of drying. Therefore, set the manual unloading speed as close as it should be for the grain currently in the dryer before
switching to moisture control mode. The manual speed setting does not have to be adjusted after the moisture control is
activated.
DRYER OPERATION - INTERMEDIATE MOISTURE CONTROL