This system monitors production count and machine downtime. It also consists of an EZPLC working as a “black box” productivity monitoring control unit, the EZMarquee, and a EZTouch HMI with built-in Remote Capability. The EZPLC gets machine down signal from a machine controller/PLC. Operator is then prompted to enter a code indicating reason for machine being down. In addition the productivity monitoring control unit tracks the time that the machine remains down. Production count, downtime and the reason code are displayed on the EZMarquee.
Motion control generally means the use of servo and/or stepper systems as the “muscle” to move a given load. These motion control systems are capable of extremely precise speed, position, and torque control. Some applications require such extensive motion control, but the budget does not allow for the use of an expensive Allen-Bradley ControlLogix PLC. Hence, in this applications note the system controls the Motion and Position feedback of a Servo and/or Stepper Motor using a low cost AB MicroLogix 1400 and EZAutomation’s EZTouch I/O.
Applications that require position feedback such as in conveyors, converting, printing, metal forming, filling, stamping and many others require an encoder that ties back to a PLC typically via high-speed counter inputs, resolver inputs or DC inputs depending on the type of encoder used. This often results in having to expand the I/O modules on already expensive PLCs. For example, if using an Optical encoder, one must have a minimum of 3 high-speed counter inputs for the ‘A’, ‘B’ and ‘Z’ signals. In the case of absolute encoders, 12 separate DC Inputs are required to obtain at least 12-bit resolution (4096 PPR). Finally, in the case of a resolver encoder input on a Control or CompactLogix PLC from Rockwell Automation, one requires an expensive AMCI Module that eats up one of the rack slots.