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  1. #141
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    The encoder number doesn't pin down a specific motor just narrows it down some. One thing it does though, is identify that the encoder has 3000 steps. The open hole in the encoder cover really bothers me. Most have solid covers and gasket or o-ring that seals the unit.

    Your video is a bit blurry when you try to look at the terminals on the bottom of the drives, and turned sideways. However, the smaller black wires on the left set of terminals should be labeled R,S,T and are inputs. The larger black wires on the right terminals should be labeled U,V,W and ground(yellow and green wire), they are the output wires to the servo motor. Disconnect these wires from the drive and measure resistance of each of them to the cable housing and ground wire. If none of them show continuity to the cable/ground wire, then test between the wires themselves like you did on the motor pins(the readings you got indicate that the motor windings are good). Just make sure the other end of the wires are not touching anything. Anything other than infinity means there is a problem with the wires. Then you should try to test each wire to see that they are intact from one end to the other. Easiest way to do this is to jump any two wires together at one end and check for continuity at the other end. Swap jumpers around until all three wires have been tasted. Just an FYI, this cable does not normally move with motion of the machine unlike the X axis cable that moves with the carriage.

    If you look closely at the drive boards there should be a paper label with the drive part number printed on it on the mounting board underneath the RST/UVW terminals.

    Normal amount of chips behind the covers.
    Last edited by alphonso; 09-04-2018 at 08:54 AM.

  2. #142
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    Disclaimer: I have absolutely no knowledge of this machine.

    I have a question. Is it possible to swap the axis' by switching plugs, so z axis problem would then relocate to x axis problem via error code? Kind of like swapping a known good/running cdi for a no spark issue on a motor, to eliminate the cdi and point to the stator or coil? (not the best reference, but hoping you get it)

    If this is possible, it may narrow it down as to the problem. ARe the boards, encoders, and drives interchangeable?

  3. #143
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    Quote Originally Posted by Ox View Post
    You should prolly unhook the warrs from the amp too.

    Did you try the L1, L2, and L3 on the other amp at all?


    ----------------

    Think Snow Eh!
    Ox
    Power was off at the machine.

    I tried the x axis board first, as that's what the tech said was the Z axis. But didn't get anything. I went to the board in the video and was able to get ground continuity so felt fairly sure that board was the Z axis.

    Quote Originally Posted by alphonso View Post
    The encoder number doesn't pin down a specific motor just narrows it down some. One thing it does though, is identify that the encoder has 3000 steps. The open hole in the encoder cover really bothers me. Most have solid covers and gasket or o-ring that seals the unit.

    Your video is a bit blurry when you try to look at the terminals on the bottom of the drives, and turned sideways. However, the smaller black wires on the left set of terminals should be labeled R,S,T and are inputs. The larger black wires on the right terminals should be labeled U,V,W and ground(yellow and green wire), they are the output wires to the servo motor. Disconnect these wires from the drive and measure resistance of each of them to the cable housing and ground wire. If none of them show continuity to the cable/ground wire, then test between the wires themselves like you did on the motor pins(the readings you got indicate that the motor windings are good). Just make sure the other end of the wires are not touching anything. Anything other than infinity means there is a problem with the wires. Then you should try to test each wire to see that they are intact from one end to the other. Easiest way to do this is to jump any two wires together at one end and check for continuity at the other end. Swap jumpers around until all three wires have been tasted. Just an FYI, this cable does not normally move with motion of the machine unlike the X axis cable that moves with the carriage.

    If you look closely at the drive boards there should be a paper label with the drive part number printed on it on the mounting board underneath the RST/UVW terminals.

    Normal amount of chips behind the covers.
    I looked over the whole motor twice and didn't see a number, I should have gotten more pictures, but must not have been thinking at the time.

    Ok I'll try those tests next. Not sure why the video came out that way, may have been because I uploaded it from my phone while I was at the farm.

    Quote Originally Posted by woodsrider845 View Post
    Disclaimer: I have absolutely no knowledge of this machine.

    I have a question. Is it possible to swap the axis' by switching plugs, so z axis problem would then relocate to x axis problem via error code? Kind of like swapping a known good/running cdi for a no spark issue on a motor, to eliminate the cdi and point to the stator or coil? (not the best reference, but hoping you get it)

    If this is possible, it may narrow it down as to the problem. ARe the boards, encoders, and drives interchangeable?
    The tech did that and I believe the Z axis code went away.

  4. #144
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    Power may have been off, but the warrs were still hooked up.
    You can get false continuity that way.
    Especially with ground.


    --------------

    Think Snow Eh!
    Ox

  5. #145
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    Quote Originally Posted by Ox View Post
    Power may have been off, but the warrs were still hooked up.
    You can get false continuity that way.
    Especially with ground.


    --------------

    Think Snow Eh!
    Ox
    Ok I get what your saying now, I'll unhook the wires from the board and retest when I'm back at the machine.

    Is there anyway to do any basic multimeter tests on the encoder? If the motor is good, seems to be (atleast no egregious faults), encoder might be the issue.

  6. #146
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    Quote Originally Posted by alskdjfhg View Post
    Ok I get what your saying now, I'll unhook the wires from the board and retest when I'm back at the machine.

    Is there anyway to do any basic multimeter tests on the encoder? If the motor is good, seems to be (atleast no egregious faults), encoder might be the issue.
    If you get some kind of resistance in the motor wires, there may be corrosion/crap inside the cable connector at the motor end.

    About the only multi meter test for the encoder I know of is to turn the motor slowly while hooked up to the Hall effect wires and see if the continuity changes when the index passes by. This is usually easier to see by using an analog meter because the pointer will jump. On a digital meter, it usually doesn't react fast enough to get a reading.

    I think I have some info about the encoder wiring somewhere. I'll try to find it today.

    Going back over the thread, I found some better pictures of the servo motor. It appears that it is a motor with a brake. I suspect that the motor is not original to the machine.

  7. #147
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    Regarding the "index" or "home pulse", that very well may be true, but near as I can guess - not relivent to this situation.

    If the machine came "up" and faulted out during HOMING, then the home pulse would be of concern.

    The encoder very well may be bad, just saying that testing the home pulse is not likely going to help you.
    Not that he was saying that it would, but just don't want you wasting time chasing that snipe.


    --------------------

    Think Snow Eh!
    Ox

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    I realize I may not know all that much on the subject, especially for a fanuc machine. BUT, has anyone considered the possibility that there isn't actually anything wrong with it and that the turret moved during shipping E.G. it wasn't rigged properly somewhere during its travels? Enough that the turret has moved beyond the machines expected window of variation? I had this happen to mine when I moved it and it wouldn't home until I adjusted the home distance parameters to account for shift and then restored the parameter back after the initial home.

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  10. #149
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    Quote Originally Posted by TheTalman1 View Post
    I realize I may not know all that much on the subject, especially for a fanuc machine. BUT, has anyone considered the possibility that there isn't actually anything wrong with it and that the turret moved during shipping E.G. it wasn't rigged properly somewhere during its travels? Enough that the turret has moved beyond the machines expected window of variation? I had this happen to mine when I moved it and it wouldn't home until I adjusted the home distance parameters to account for shift and then restored the parameter back after the initial home.
    I don't think that is the problem as the error code indicates an over current condition. And, I think the carriage is off the travel stop dogs. May have more info about error cause after I look at the machine Sunday.

  11. #150
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    Buy a megger. A megger will show you just how useless a standard ohmeter is for testing wires and motors.

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  13. #151
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    Tom came to look at the machine Sunday.

    Now the confusing thing is that the Z axis servo is out, but were still getting an axis error and the board isnt showing an error light.

    Leading Tom to think the board may be the issue.

    Took some more pictures of the electrical stuff, but may not be of any use to anyone.

    Sent from my SM-G965U using Tapatalk


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