What's new

Search results

  1. M

    Fanuc Repair Gurus - Brain teaser of the week... 21iT tale of woe..

    We should make the distinction of hard limit switches (physical switches) that signal the control to decel the axis to 0 and display an overtravel alarm versus emergency hard limits that are wired in the E-stop string, such that hitting one causes the servo drives (and whatever else) to shut...
  2. M

    Fanuc Repair Gurus - Brain teaser of the week... 21iT tale of woe..

    Don, tried to sent PM but your box is full.
  3. M

    Fanuc Repair Gurus - Brain teaser of the week... 21iT tale of woe..

    I'm waiting with baited breath (WTH does that expression mean, anyway?) to see if it's that card. I've been suspecting that's been the problem. I hope it is, since that's relatively easy and inexpensive.
  4. M

    Fanuc Repair Gurus - Brain teaser of the week... 21iT tale of woe..

    Don, I've had to replace these type boards a couple of times, either the Axis Control or the Servo Interface modules mounted on the MAIN (I'm talking 16/18/21, not the i series, as I previously mentioned, but I suspect they are similar). They're pretty damn reliable, but anything can fail, of...
  5. M

    Fanuc Flash-RAM expansion.

    Where is the slot to mount the card? I don't think it is strictly the i series that can do what you want, but the 20 wasn't designed to be a higher-end unit, so somewhat limited compared to other Fanuc models. Your memory capacity is upgradable, if it's not at the max of the control's...
  6. M

    spindle died last night le blonde makino fnc-74

    Huh? I'm missing something here. These statements seem contradictory. If it's not a cartridge-type, what are you going to "send out"?
  7. M

    Fanuc Flash-RAM expansion.

    As you've discovered, a CF card in an adapter is not necessarily the same as a real PCMCIA memory card. On some Fanucs, the CF will indeed work, and this is most of them. But, for a few (sorry I don't know specifics), they have to have a genuine PCMCIA memory card.
  8. M

    Setting Up a Fanuc 18T

    WHAT position reads that value? You have ABSOLUTE (which shows where the tool tip is within the current coordinate system for that tool, moved by the programmed command), RELATIVE (which can be relative to anything, depending on where you zero it out) and MACHINE (the distance from home...
  9. M

    Fanuc Repair Gurus - Brain teaser of the week... 21iT tale of woe..

    Don, The i controls in my customers' base have been so reliable that I've never needed to take apart any of that stuff. I'm ignorant on what's inside. (I'm assuming you have the whole compact control right behind the display.) But, I might be able to answer one of your questions that possibly...
  10. M

    E-Stop spindle drop? Fanuc 20-F

    You didn't say, but I'll assume (I hate that) this is a VMC, because you said it was a Z motor. Many VMCs have a brake to stop the head from free-falling (more like coasting) when the servo power is removed, like pressing E-stop does. It's common for the axis to drop slightly between power...
  11. M

    On Fanuc "i" controls, how long will parameters stay with battery disconnected ?

    I think you're right, Don, that you could change it powered up. Actually, I had not run across that procedure to power it off first. However, I would want it on more than 30 seconds to let the supercap charge before I relied on it to hold the memory. Just me personally, I'd want it on 10...
  12. M

    Guess the ratio of machining centers equipped with linear encoders vs rotary only ?

    Don's question specifically asked about machining centers, not grinders, boring mills, knee mills, VTLs, etc. Surely these machines benefit from linear scales, but they're not MCs. I agree with Don that less than 5%, and I would guess 2%, are equipped with linear scales for position feedback...
  13. M

    Centripetal Force

    Spot on, Bill. Well said. (As usual.)
  14. M

    Modern CNC machine building tolerances

    Nope. Modern controls (and some 25+ years ago) can compensate for many of these misalignments. Most any control in use today would have at least pitch-error comp, which adjusts for inaccuracy of lead for each segment of a ballscrew's travel. The segment length can be defined, and would commonly...
  15. M

    Mori Seiki SL-0 Alarm code

    Hmmm, a couple? Looks like 6 to me. Can you tell us what the manual says the other alarms are? Without knowing what they all are, I'd take a WAG that this is a system corruption. Have you checked your 3volt lithium backup battery? It's about a "C" size, bright yellow. Uh, don't disconnect...
  16. M

    Which CNC controls to avoid?

    Agreed. I haven't needed to call Mits tech support very often, but they have generally been helpful and friendly, including reloading params on an old Meldas. My comment isn't toward the support, but the control itself. For instance, one I worked on had an I/O problem. The I/O was integrated on...
  17. M

    Question- How to test a Fanuc power unit?

    There are check pins along the top or bottom edge, inside the case, where you can connect scope probes or meter lead clips. The pins are labeled as to what voltage you're checking. It's in the Maintenance Manual. That mfg. number is the serial number, so irrelevant. The Type No. is the part...
  18. M

    Makino FNC 60 Servo Alarm "VRDY OFF"

    Greg, the EMG relay should always be on. When the string is broken, it will go off. The NOT READY and the alarm 401 usually are together. But, if it is in E-stop, that EMG relay wouldn't likely be energized. Perhaps it's wired differently than most other brands. On reseating chips, try to be...
  19. M

    Makino FNC 60 Servo Alarm "VRDY OFF"

    This could get ugly, Greg. Yes, an E-stop condition would usually mean a NOT READY. I have seen a 401 alarm without the NOT READY, but I don't think it was a 0 control. The control has to put out a servo-on command to the drives, then they have to turn on and answer quickly that they are...
  20. M

    Makino FNC 60 Servo Alarm "VRDY OFF"

    Check the wiring diagram for the E-stop string. A 401 is a generic "servos went off when not expected" usually due to a broken E-stop string. I would think about a dirty contact in a limit switch, E-stop switch, breaker, thermal overload, etc., anything that might be in the string. Use a meter...