Grain Systems PNEG-1851 - Manual (Page 45)

Chapter 5: The Drying Modes
Figure 5-4 Speed versus temperature relationship for the 5-speed temperature control scheme
Continuous Flow Based on Grain Moisture
Moisture-based control schemes in continuous flow use grain moisture as their reference parameter. As
the grain’s moisture content rises or drops, the unload speed automatically adjusts according to the
selected control scheme
How It Works
As opposed to grain temperature, the dryer’s unload rate is inversely proportional to the grain’s moisture
content—as the moisture rises, the unload rate decreases. The grain’s moisture content is monitored by
the dry sensor, which is located next to the grain discharge box.
Let’s assume a grain moisture setpoint of 15%. If the dry sensor reports a moisture reading of 16%, the
grain is one percentage point higher than the target moisture content. As a result, the selected control
scheme automatically decreases the unload speed, thereby increasing the length of time that the grain
spends in the grain columns. The opposite is also true. If the dry sensor reports a grain moisture reading of
14% (one percentage point below the setpoint), the unload speed automatically increases.
The 5-Speed Control Scheme
The 5-speed control scheme is the moisture-based scheme that is available in continuous flow. In this con-
trol scheme, you enter the following parameters:
• The reference speed
• The grain moisture setpoint
• The metering roll speed’s inner offset
PNEG-1851 Vision N2 45