BR063

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Posts posted by BR063

  1. Posted · Edited by BR063
    No Brake on spindle Motor

    In this same project I control a 3HP motor that drives my spindle through a Gearbox. It now has an encoder attached to it so that the servo drive can synchronize feed rate with its RPM.

    Works great!

    I am trying to stop the VFD spindle at a radial position. I used 3.0 Hz to rotate to a proxy flag and change speed to the lowest possible setting (0.2 Hz) and stop at the next flag. It works okay 9 times out of 10. The accuracy is good enough, my deceleration and acceleration times are set to there lowest values. Is there a way to use encoder that is wired into the 0.00 and 0.01 as well as my proxy flag to accurately stop this motor? I figured the proxy setting accuracy would be enough but the motor is stiffer than usual because of the gearbox. I know the CP1L can control an inverter but extra hardware is needed and I am not sure if it can control a both a servo and inverter motor at the same time.

    At present i will try adding a second proxy to flag if it over shoots the 1st proxy edge and have the motor reverse and retry until both proxies are on after edge detection. I am pretty sure that will work but don't like seeing a spindle search for its home over and over again.

    Forgot to add the Spindle motor has no brake as it never needed one.

  2. Posted · Edited by BR063

    I did not realize that my output mode was set to Pulse  + Direction. I guess it should have read #0010 for CW/CCW rather than #10 on each of the SPED commands. That is why I thought it would work with the default settings. If so that is my mistake in the interpretation. If I change this to read #0010 it should work with the default settings. Or should it be #0000 0000 0000 for CW and #0000 0001 0000 for CCW? Not sure

  3. Posted

    I have all my components wired in. Did a Servo test run and the servo works. I see my pulse output on the PLC lights flickering but the Servo doesn't run.

    I had to wire in an output to activate the Run on the servo to pull in the brake. Servo doesn't seethe pulses. What am I missing?

    I am not sure how to monitor the high speeds Output 0, (100.00, 100.01) real time in CX-Programmer.

    I wired it up the same as the attached drawing with the exception of the fact that the PLC in the drawing is Sourcing outputs so I have:

    CP1L-M60DT-A to R88D-KT08H with R88M-K75030H-BS2 Motor

    100.00 to Pin 4-CW (Note: Not using Shielded twisted pair for these)

    100.01 to Pin 6 -CCW

    100.04 to Pin 29 RUN

    -24V to Pins 10 BKIRCOM (Do I need to connect to Pin 25?)

    +24V to Pins 1,2,7

    I am not using Origin Search so no other connections on CN1

    Would appreciate any help.

  4. Posted · Edited by BR063

    I have all my components wired in. Did a Servo test run and the servo works. I see my pulse output on the PLC lights flickering but the Servo doesn't run.

    I had to wire in an output to activate the Run on the servo to pull in the brake. Servo doesn't seethe pulses. What am I missing?

    I am not sure how to monitor the high speeds Output 0, (100.00, 100.01) real time in CX-Programmer.

    I wired it up the same as the attached drawing with the exception of the fact that the PLC in the drawing is Sourcing outputs so I have:

    CP1L-M60DT-A to R88D-KT08H with R88M-K75030H-BS2 Motor

    100.00 to Pin 4-CW (Note: Not using Shielded twisted pair for these)

    100.01 to Pin 6 -CCW

    100.04 to Pin 29 RUN

    -24V to Pins 10 BKIRCOM , 8 and 9 (Do I need to connect to Pin 25 or 33?)

    +24V to Pins 1,2,7

    I am not using Origin Search so no other connections on CN1

    I will try -24V to Pin 33.

    Would appreciate any help.

    R88M_KT08.cxp

    I571-E1-05 598.pdf

    Connecting CP1H-X40DT1-D.pdf

    I571-E1-05 135.pdf

  6. Posted

    I put that number in as a reference for now. I am not sure what it will be at this point. My encoder monitoring my spindle RPM is an Omron E6C2-CWZ6C-1000P/RM. The servo motor and drive are R88M-K75030H-BS2 and R88D-KT08H. At this point I am not even sure how many pulses per rev is on that motor and drive. 

  9. Posted · Edited by BR063
    Wiring encoder question

    Thanks alot for the help. That's a really neat instruction. I need to have  both CCW and CW rotation for the Rapid to lower the spindle when it is at 0 rpm. Spindle raise with 0 rpm will only be fast. Does this look about right? Also on wiring this up does the plc only use the A and B phase or is the Z phase also needed in this application?

    CP1L_SERVO_SPEED_CONTROL3.cxp 

  11. Posted

    I understand that I wire the encoder on my spindle into the CP1L's high speed counter. In order to monitor its frequency rather than value how do i do that. Is it through the PRV instruction? I need to monitor that value to set my pulse output in realtime. If the spindle rpm goes up or down my feed has to as well.

  12. Posted

    57 minutes ago, BITS N BYTES said:

    Correction:- IF the complete part number of the PLC is CP1L-M60DT-D then the outputs are SINKING and should interface directly with the Servo wired as Open Collector Inputs.

    Easiest way of scaling your desired speeds is to use the APR instruction. This will scale input speed from encoder to desired output speed for servo.

    If you intend to use the SPED command this suggests you are only concerned with RPM and not concerned about position. Remember that this command has no ACC/DEC associated with it. So the ACC/DEC parameters in the Servo drive will be the governing factor as to motor performance.

    The easiest way? I looked at the APR instruction and can barely understand it. I guess I have a lot of research ahead of me. This is proving to be tougher than I thought. Thanks

  13. Posted

    Thanks, 

    I am not concerned with the position when i am running at the set feed rates as long as it is synchronous with the spindle RPM. I have a limit switch at the top and bottom of the total stroke that will stop the feed at the bottom. There is a 2-hand anti tie down that activates spindle rotation so spindle rotation and feed will stop when the operator releases or it hits either limit switch. I may look at the homing function more closely in the future when i have time to play with this but for now the limit switch should be sufficient.

  14. Posted

    2 hours ago, BITS N BYTES said:

    The CP1L model you have has SOURCING transistor outputs so your selected servo must have pulse train inputs that match this specification.

    You can control the servo using either PULSE & DIRECTION or CW & CCW high speed outputs from the CP1L.

    Rather than adding an external encoder use the encoder output signals from the servo drive [a common feature of most servos] as high-speed inputs to the CP1L.

    You then have full control of speed and position of the servo within the PLC.

    Adding CW limit , CCW limit and ORIGIN sensors would enhance the operation of your system.

    Attached is excellent document from Jay Anthony at MRPLC that covers Motion using a CJ1M. Though the physical I/O connections are different, the principles apply equally to the CP1L.

    [268]Omron_CJ1M_Motion_Introduction.pdf

    I am going to use a R88D-KT08H which does have pulse train inputs. Using this, what is the proper way to issue a SPED command based on what the high speed counter reads from the spindles encoder. I figure the spindle running at 150 RPM will produce a count of 2.5 revs/sec. The 2000 ppr encoder counting 4x per pulse is = 20000 Hz. With my gear ratio and 5mm ball screw pitch I figure I need to run my servo at 6.53 RPM to get 0.002" feed rate and 13.06 to get 0.004". That is a reduction of 1: 22.97 and 1: 11.48 respectively. Not sure yet how that is done yet but that is what i am trying to achieve. For fast and slow approach with 0 RPM at spindle I will need to run 120 RPM and 1500 RPM for the slow and fast advance.

  15. Posted

    I was planning on using the external encoder to monitor the RPM of the spindle which is controlled by the VFD and potentiometer. I am not sure what the RPM of the spindle is as per the operators adjustment of the potentiometer (Spindle RPM could be 100-250 RPM). Would I not just use that data and a scale function to output the required pulse to attain a constant feedrate? Or am I missing something? I realize I need to scale the RPM pulse output from the PLC based on the ball screw pitch, drive chain ratio and spindle's current RPM.

  16. Posted

    I am using a CP1L-M60DT, which I believe to be Transistor output. 

    I am replacing the VFD with a servo so that I can have better control at low RPM. I have tried to get what I want in feeds using the VFD but without the results I want. Currently the machine is gear reduced to give me a 0.002" feed rate on the spindle RPM. The ball screw nut is geared to that feed rate. I need to add a second roughing speed. I only use the VFD to spin the Ball screw for spindle advancement. In order to get the feed rate I need with the VFD I need such a large range of RPM to control the feed rate for both cutting and 2 speed rapid advance. So the variance for feed rate is around 6 to 12 Hz for cutting feed and the Rapid advance is too slow at 120Hz. So with the slower end of the scale the RPM is not very consistent (torque and RPM)and the higher end is too slow. Rather than change all the geartrain, I figured it would be easier to remove it all and fix the ball screw nut and drive the ball screw with a servo motor.

    The encoder I am using, my intent was to add this to the spindle RPM and monitor its RPM. When I want synchronized feed I will use that to set the speed of the servo output to drive the ball screw to give me either feed rate of .002" or 0.006" per rev. When I wish to raise the spindle up and down I will just run a set Servo speed for 2 speeds regardless of the spindles 0 RPM.  Does this seem feasible?

  17. Posted

    My spindle speed is limited to a range of 125 to 250 RPM max when synchronized feed rate is required. The spindle when stopped will only need to one of two preset speed to raise and lower. At those RPM the high speed counter won't keep up? I was told it would the encoder quoted to me was a E6C2CWZ1X2000PR2M.

     

  18. Posted

    I have a spindle that has a variable speed controlled by a potentiometer and a VFD (125-275 RPM). The spindle is raised and lowered for rapid up and down via a ball screw and a motor and VFD. The ball screw nut is geared for a fixed feedrate so when the spindle rotates the spindle feeds down. I need to change this to allow multiple feed speeds. In doing so I am replacing the VFD drive on the spindle feed with a Servo motor and drive.   I wish to add an encoder to the spindle and feed this to the machines CP1L high speed input. Based on spindles RPM I would like to lower the spindle at a specific feedrate as well as raise and lower the spindle fast and slow when the spindle RPM is at 0. I have never programmed a servo drive and motor before in CX-Programmer before but it is my understanding that this possible. Any help would be appreciated.