The AM3 - (Automatic Mini Moisture Manager) is a real-time in-line moisture monitoring and moisture control solution that is ideal for measuring product moisture at the exit of a grain dryer. The AM3 is also capable of some basic automatic moisture control.
The AM3 comes with one of Dryer Master's stainless steel fin type moisture sensors, a high performance ¼ DIN Micro PLC (available either pre-mounted in a Nema4 enclosure, or un-mounted for user configured installation), and an optional calibration button. The display panel is used to enter calibrations and display and store moisture information. Data storage is on a removeable MicroSD card but an optional printer is also available for those who would like an ongoing printed record.
Product moisture is measured by the Dryer Master moisture sensor and then displayed on the AM3 panel. The sensor is simple to calibrate against a bench top manual tester.
The AM3 is a state logic machine, with control adjustments made only when preset triggers are met. The operator inputs high, low, and target moisture triggers for each of three user settable discharge rate speeds and response time settings. Moisture control is achieved by switching between the discharge rate speeds as triggered by the settable moisture targets. This is a system intended for a more hands on style of operation as the speed set points and moisture targets will need periodic adjustments to maintain optimum performance.
The system interfaces with most modern variable frequency drives directly and usually only requires a small isolation interface to operate non isolated SCR controllers.
Operator involvement in making and changing the control parameters is important in achieving good results. In general the system performs best when inlet moistures and drying conditions are relatively stable and where dryer residence times are shorter. The AM3 can also be connected to a plant wide automation system.