I have several TMD+1616 PLC's on which I am using the 4 x 20 LCD displays (purchased through TRI-PLC). all are wired according to specs in regards to the current limiting resistor and using the supplied interface cable.
My problem is this,all of these units will periodically have diplay problems which usually consist of a complete black (blocked out) screen or a blank diplay altogether. If On-line monitoring is done then the PC display is correct and the PLC always performs it's tasks even in this condition. A master reset function or a reset from on-line monitoring will not clear the display,the unit must be powered down. this usually occurs at least every other day on all PLC displays.
Any thoughts or suggestions?