Actually it is a lot easier to troubleshoot a machine that is controlled with electronics. Most new sheeters have a programmable logic controller (PLC) governing the operations of the sheeter instead of relay logic. Typically a dual motor drive with two motors, two AC drive and a motion controller takes the place of the mechanical drive train. The PLC is interfaced to operator controls and the drive system.
The electronic modules of these systems have light emitting diodes (LEDs) that are crucial in trouble shooting the sheeter. By looking at the LEDs on the input and output modules of the PLC you can verify if the signal is being transmitted to a device or not. Green lights on the modules confirm that the signal is being inputted from the PLC or outputted to the device. Red lights indicate a problem.
In the case of a PLC controlled device, if it is determined that the signal is being sent to the component ( for example, the load table motor), a trained electrician should verify that the proper voltage is being supplied to the device at the time it is being run. This is done at the device’s power infeed to insure that the fuses or motor starter is not damaged. By moving the voltmeter to the component, the electrician verify that it is grounded properly or if there is noise being generated on the line causing the problem. Our experience is a loose wire or connection is the root of the grounding problem, but you could find out that the component has failed.
The drives and the motion controller also have LEDs that illuminate for a particular fault and in most cases have a liquid crystal display (LCD) that describes the status of the drives.
On MAXSON equipment, the operator’s main console includes screen that display the cause and location of a fault, jam, or open safety interlock that prevents the sheeter from running. By using the LED, LCD, or annunciated fault information and the electrical schematics for the sheeter you can isolate the component causing the problem and initiate corrective action or provide sufficient information for the sheeter manufacturer to assist you.
