Control of the Computermatic MK5B is based on the Eberle PLS 511-04 programmable logic controller.  All input/outputs can be    visually monitored on the front face of the PLC by LED indicators.  The PLC offers the advantage of   being a simple plug-in unit should substitution be necessary during maintenance.  It is however, true, that the reliability of these units goes a long way towards eliminating failure from TTL control electronics and therefore   enhances the already good reputation of the Computermatic as a long term reliable grading machine.







A four mark roller marker is fitted which allows grading details to be printed down the face of the timber as the piece leaves the machine.  The length of marked area is approximately 1 metre long.





All pneumatic control valves and operating solenoids are collectively mounted in a  separate panel this allows ease of access during any servicing.







A heavy duty  output drive roller is used to   ensure timber is driven out of the machine after the grading process, the output drive also ensures that the timber is presented correctly to the roller markers during the final grade marking.





A 25kN pressure transducer load cell is interfaced directly between the load cylinder and the load roller, this allows the load cell to accurately register the load being exerted on the timber by the load cylinder.







A digital display readout on the machine’s front panel allows the operator to see the load currently being exerted, the operator can then use this display to more accurately set the required load for grading in Newton’s instead of Kpa.





From the remote console the operator can completely control the grading machine. Controls for grade boundary settings, load   cylinder range selection and the machine’s speed are all located on the panel. Also there are readouts for both ‘A’ and ‘B’ transducers, photocells and grade piece and total counters.








The console connects to the grading machine via two 36-way connecting leads, these two leads carry all the signals required to run the machine. The standard length is of these is 5 metres.

The controls are cover by a transparent lockable hood, which whilst keeping the control panels free from dust and other debris, still   allows the operator to monitor the status of the machine.