Posted 1 Jun 2016 (edited) Hi guys, been using this site for a long time, it has come in handy alot. However I have recently taken on my first servo project, heres an overview of the project We have a filling machine that has a separate dosing system to the filler head. It used to keep the dosing in time by adjusting a 0-10v signal to an inverter to make sure that a flag makes a sensor in a set window. I have installed an encoder on the filling head and an mpl servo to the dosing. I have then used an MAPC instruction to follow the encoder, the cam is 0-360 and it follows a straight linear line. I have installed of this as a temporary set up on one of the filling machines (we have 2) and it is working perfectly. I have now installed this on the second machine as a permanent set up with a panelview plus 7, L71 cpu. However it is giving a very strange problem on first power up, the encoder is giving the exact same position as before it was powered down. however as soon as the MAPC executes the servo axis faults, giving an overspeed fault. the servo doesnt even look like its attempting to move (however it is through a 10-1 gearbox). if i then home the encoder it then runs absolutely perfectly until it is powered down again. I am beginning to think it may be to do with the master lock and cam lock position, as the cycle stop position of the two machines are different. however I just cant seem to get my head around i the difference between them. Hopefully that makes sense any help would be greatly appreciated Thanks Rhys c1_dosing.ACD Edited 1 Jun 2016 by rhys_m Share this post Link to post Share on other sites
Posted 3 Jun 2016 Me again, some more info for this imcase anyone can help. I have hooked the encoder up off the machine and slowly turned it by hand to identify where it causes the servo to trip. It turns out that when the encoder isnt homed it will try and lock the servo at 0 degrees even though I have written in the program to lock at the actualposistion of the servo. As the servos stop position is 286 degrees this then causes the overspeed/posistion error The encoder is reading the correct position before homing, but once it has been homed it will then lock at the correct position. I have spoken to rockwell via out techconnect and they wernt particularly helpful :(. Any guidance would be greatly appreciated Share this post Link to post Share on other sites
Posted 3 Jun 2016 Some bug in the forum is keeping me from downloading the program file... What is different in the hardware/software setup between the two machines that might cause it to act differently? Share this post Link to post Share on other sites
Posted 3 Jun 2016 The original is made up of the following 1756 L61 cpu version 19 1756 m03se Sercos card version 19 2094-bc02-m02-s High resolution multiturn servo and encoder The new panel has the same except for 1756 l71 cpu version 24 I have literaly just found the following on a kinetix 6000 bulletin 2094-xCxx-Mxx-S and 2094-xMxx-S CORRECTED: Loss of absolute reference status after power cycle for feedback-only axis. Sounds like it could potentially be my issue, the test rig was made of 3 year old + drives from Stores. For the new panel everything was just ordered in. Just phoned someone at work to find out the version of the drive. Not sure how to flash one of these though. o_O Share this post Link to post Share on other sites
Posted 3 Jun 2016 Hopefully that makes all things better! Have fun with the firmware upgrade. I did one maybe five years ago. I don't remember the process exactly, but it wasn't too traumatic. I had tech support walking me through. Share this post Link to post Share on other sites
Posted 3 Jun 2016 I have read that before a certain firmware you needed a Sercos adapter to be able to do it. Hopefully im after that and can use drive Explorer, fingers crossed. Thanks for the reply, il update the thread once done, heres to hoping! Share this post Link to post Share on other sites
