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  1. #13
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    Than you. It was only a curiosity. I have already read all the documentation and I understand now.
    I have a confusion. If I use JP7 bit 8 to bit 15 for Step Dir(CL step) and bit 0 to 7 for encoder, Any other LVTL 3.3v can be used for home and limits? (I will use an opticall isolated board with filter for the connection of the endstop).

    Thank you very much!



  2. #14
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    Default Re: Encoder for stepper motor

    Hi ssjantonio,

    Limits, Home Sensors, and Index Pulses are handled in software so they can be connected to any spare input. Those listed are only suggestions.

    HTH
    Regards

    TK
    http://dynomotion.com


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    Hi Tom. I'm testing my encoders but I'm doing something wrong because the curve of position is displaced from the command curve. I have attached an image. The gain is ok. Do you know why happend that?. Is the same in the 4 axes. The displacement depends on the position of the motors.
    Thank you for your help!

    Attached Thumbnails Attached Thumbnails Encoder for stepper motor-20161003_110502-640x480-jpg  


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    Default Re: Encoder for stepper motor

    Hi ssjantonio,

    You need to initialize in a way that matches the Commanded Destination and the Measured Position.

    One way to do that is to Zero(X); the axis That will set them both to zero. (There is also a Zero button on the Step Response Screen).

    Another approach that allows re-initialization without loss of position is to Enable the Axis and set the Destination to the Measured Position. With (for Axis 0):

    EnableAxisDest(0,ch0->Position);

    Regards

    TK
    http://dynomotion.com


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    Quote Originally Posted by TomKerekes View Post
    Hi ssjantonio,

    You need to initialize in a way that matches the Commanded Destination and the Measured Position.

    One way to do that is to Zero(X); the axis That will set them both to zero. (There is also a Zero button on the Step Response Screen).

    Another approach that allows re-initialization without loss of position is to Enable the Axis and set the Destination to the Measured Position. With (for Axis 0):

    EnableAxisDest(0,ch0->Position);

    Regards
    I have tried the zero button in the step response screen, but nothing happend. My motors are steppers, is the same history?. Tomorrow I will to try with EnableAxisDest. Thank you!!



  6. #18
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    Default Re: Encoder for stepper motor

    Hi ssjantonio,

    Strange the Zero button wouldn't Zero the Destination and Position. It should for any Axis type. Check the KMotion Axis Screen to see what they do. You may have noise or miscounting so they drift apart.

    What do you mean by: "The displacement depends on the position of the motors"

    Also post a screen shot of your Config Screen.

    Instead of taking a photo please use Alt-Print-Screen to capture the Window and paste to a *.png file to upload.

    Regards

    TK
    http://dynomotion.com


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    Hi Tom. It is working now, I was wrong because the zero button is working fine, thank you very much.
    I have another question. I have a siemens VFD with ansyc motor. The vfd is controled by a plc with modbus and the pwm output from kflop is connected to the PLC, everthing is workin fine, the question is; with this configuration is possible to make a closed loop with the encoder connected to the spindle? I have read about CL with Kanalog ADC output, but I cant found information about pwm directly from kflop. My intention is implement rigid tapping.



  8. #20
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    Default Re: Encoder for stepper motor

    Hi ssjantonio,

    Closed loop Spindle Control may be possible. Performance will depend on how quickly the PLC and VFD respond to speed and direction changes. Can the PLC drive the spindle both directions? There isn't any direct PWM Output Type. You must use a small C Program to write the Servo Output to the PWM in the appropriate manner for your device. Set the Axis Output Type to "No Output" as the C Program will be doing the Output. I've attached an example.

    HTH
    Regards

    Attached Files Attached Files
    TK
    http://dynomotion.com


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    Default Re: Encoder for stepper motor

    Hi Tom, our kflop board was damaged, I think because of some voltage peaks. I have purchases Kflop + konnect, can you send it by another express priority service? Does not matter if it cost more.
    Thank you!



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    Default Re: Encoder for stepper motor

    Hi Tom. I want to use the Z index of the encoders for homing, but this is 5V, it is possible connect it to a LVTL 3.3V input with a resistence? wich resistence could work?
    Thank you!

    Last edited by ssjantonio; 10-14-2016 at 03:30 PM.


  11. #23
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    Default Re: Encoder for stepper motor

    Hi ssjantonio,

    KFLOP 3.3V inputs will be damaged if driven hard above 3.8V. Most 5V TTL signals do not drive that high as they are only required to drive above 2.8V. Unfortunately the maximum is not usually specified.

    You might measure the voltage with a voltmeter. JP4 and JP6 have 150ohm pull down resistors which make it more unlikely for the voltage to be above 3.8V. I have never had a case where there was a problem connecting directly.

    But to be absolutely safe you might add a 47ohm series resistor. Combined with the 150ohm pull down resistor will reduce the pin voltage to ~75% of the output voltage. You should check if the pin voltage is still at least 2.4V

    HTH
    Regards

    TK
    http://dynomotion.com


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    Hi Tom. I have checked the output voltaje of the encoder. A and B have 2.4V max. But i cant measure any voltaje in Z, but in Z- it reads 3.4V.
    I have done 2 tests:
    1.- With the konnect input common to digital GND and IO1051 connected to Z of the encoder.
    2.- Z phase connected directly to IO16 in Kflop.
    The code that Im using is this simple:
    Jog(0,100);
    while(!ReadBit(16 or 1051));
    Jog(0,0);
    In the first case it works nicely but only when the encoder is not connected to ground earth.
    In the second case it does not work in any way. I cant understand why if the digital io windows shows io16 as low, the function ReadBit(16) always return high.
    Maybe i'm not grounding correctly the encoder?.
    The machine is connected to ground and the encoder receives ground from the machine, the cable is not connected to earth, maybe that is wrong.
    The encoder is a chinesse clone of Omron e6b2-cwz1x.
    I forgott, kflop counts correctly the pulses of the encoder.
    Can you suggest what can I do?
    Thank you very much for your help!



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