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Emach

Machine Commissioning

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Anyone out there who could provide a rough series of events for commissioning a machine? The machine has been wired and power has been connected but not turned on. Currently I am working on the PLC program but once I’m done with the program I would like to have some steps to take to safely bring the machine online. Thanks, Emach

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It really depends on the machine. An extruder would be different from a packaging machine would be different from an autoclave, etc. In general, though, you'll want to do a thorough I/O check to confirm wiring, check your safety circuit, bump motors to make sure you've got rotation and scaling correct (I sometimes decouple the motor first), then do a low-speed dry run (no product, materials, etc) to check your sequence/process, clearances, etc. This last will often require some jumping through hoops to flag sensors, etc. Now you're ready to do a low-speed run with material and/or product and start tuning in the machine (speeds, timers, PID loops, etc.)

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JROSS low speed starts are only for old timers that have screwed up more than one machine on startup. I use to check I/O and drives then let it rip. Now not so much if possible I break the machines up into small sections and SLOOOOOOOW as possible. Side note document, document, document. I don't think you can over document. Startup notes are usually left for the maintenance guys. I make copies if the engineer wants them. But 90%+ of the time the notes don't ever get from the engineer to maintenance if I don't pas them along. Some lessons are learned the hardway.
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good topic.... in simplest form it would be something like this: inspect and power it up in stages, section by section (breakers, fuses...). depending what you are dealing with, you may want to use proper protective gear. next check safety circuits and any interlocks. do the I/O check point by point and make sure each and every one is set / calibrated correctly (before you start debugging code). also verify that signal polarity (NO/NC) matches drawings. we normally make plenty of diagnostic options with all I/Os on the HMI screen with manuals controls, overrides etc. if this is not the case, you may leave PLC in stop mode and toggle outputs for example (if there are no interlocks). be careful with forcing I/O, make sure you know what you do and how PLC and software behave. after I/O check, normally alarms are checked/simulated (this will be very handy in the next part). eventually it is time to try bigger things and anything causing motion (bump AC motors, check directions, jog servos, adjust home and over-travel sensors, verify they are working ok, verify position scaling, verify all motion outputs are controlled by safety circuit etc.). once everything is powered up and checked out, it is time to look into debugging of the software. again, start small and gradually bring up the entire system. for example after ensuring interlocks and safety is ok and everything works in manual mode, i would turn on semi or auto and use step mode to test program sequences. when that works fine too, full auto, otherwise - back to it until it's fixed (hopefully it never gets to panic mode)

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In addition to the good comments already made: Before you allow control power to any electronic equipment, isolate it from the main control power source(s) and make sure the voltage you will be applying is correct. You don't want to find out someone missed a jumper setting on a transformer after you apply 240vac to your 120v power supplies or safety relays or all of your sensors... This was mentioned already, but for emphasis: Check directions of all motors. Some equipment doesn't like running backwards so use caution, and decouple where mechanical damage from reversing could be an issue. Edited by OkiePC

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