MIAC (Matrix Industrial Automotive Controller) is a rugged programmable controller that provides 8 analogue/digital inputs, 4 relay outputs, 4 transistor outputs, a 4 x 16 character LCD, a 9-key keypad, a CAN bus interface, and a USB programming/communication port. All this is available in a small DIN rail and screw hole mountable enclosure with heavy duty terminals.
The latest version of Flowcode includes a MIAC programming application, USB drivers, documentation, and a MIAC component that provides the necessary control functions and full simulation.
An example of a simple industrial application is a timer relay. This produces a fixed duration output when triggered by an input signal. In most cases the input signal does not have the correct power or timing characteristics to drive the required load, and the timer relay is used to correct both of these problems. Increased flexibility can be provided by adding the ability to delay the output signal after receiving the trigger signal (on delay), and to delay the detection of the next trigger signal after completion of the output period (dead time)
To take advantage of some of the additional features provided by the MIAC, the three timing steps can be individually programmed using the keypad and LCD.
The keypad keys do not have any functions assigned to them and simply return numeric values when tested by the program, but have been laid out to represent a ring of 4 cursor/navigation keys with a central confirmation button. The remaining 4 keys are individually coloured and have helpful icons on them.
The green key has a menu icon on it and is used in the example program to enter the setup menu for the relay (when the relay has not been triggered), temporarily disabling operation. The setup menu contains a sub menu to allow selection of one of the three timing parameters for adjustment, or to return to the operating mode. Selection is made using the up and down cursor keys to highlight the required parameter, and the OK key to make the selection. The numeric value of the parameter can then be adjusted using the up and down cursor keys. The OK key completes the adjustment and returns the display to the selection menu.
The example program reads the trigger signal as a digital input. All the MIAC inputs are 24V tolerant and can be read as either analogue or digital values. Analogue conversion is linear from 0V to 12V and has a resolution of 20 counts per volt. This feature allows a range of input options to be added to the relay program (analogue threshold detection etc.) - and to all other applications.
The example program can also be easily modified to produce a complex sequence of signals on any or all of its output terminals, or to react differently to its input signal(s), e.g. produce a continuous output sequence while the input trigger condition is present.
The relay contacts are rated at 8A, 240VAC, 30VDC, and are fully isolated.
The transistor outputs (A, B, C, D) could be used as easily in this application. They are referenced to 0V and supplied from the M terminal (6V - 24V). Each output can source and sink 500mA continuously and is capable of much higher switching frequencies (40KHz) than the relay outputs (50Hz). The delay times for a transistor output version of the example program could be changed from seconds to milliseconds if required. Some of the run mode display messages could also be removed in this case.
The MIAC has been designed to work with some of the existing Flowcode components:
- The PWM component can be used with the A and C transistor outputs.
The CAN component can be used to provide a CAN bus interface on the H and L terminals (all the necessary hardware is contained within the MIAC). A terminating resistor can be added by shorting the TA and TB terminals together.