9
Chapter 3
Control Components of the FBD
The DVX Fluidized Bed Dryer is an automated machine, which means that instead of
having dials or mechanical devices to control the air flow, deck speed, and other compo-
nents that have to be individually controlled in a mechanical way the entire process is
done via a Human Machine Interface (HMI) and a Programmable Logic Controller (PLC).
The HMI is a touchscreen that allows the user to input desired settings, which are then
transferred to the PLC, which then uses its internal programming to run the machine.
The PLC is like a small computer. It has a processor, memory, inputs, outputs, and a
small display for additional controls. It is the brains of the automated machine. One
additional component to the automated process is the Powerflex 40 Variable Frequency
Drive (VFD). It is what the PLC uses to give exact control over all of the fans and the
eccentric motor. It is critical to know and understand the difference between the three
when going through the guide.
Figure 3.1:
The Programmable Logic Controller (PLC) CompactLogix L2
