mazak/hundai qt15n chuck sometimes wont open so alarms out when bar pulling - Page 2
Close
Login to Your Account
Page 2 of 3 FirstFirst 123 LastLast
Results 21 to 40 of 60
  1. #21
    Join Date
    Sep 2006
    Location
    Abingdon, VA
    Posts
    3,775
    Post Thanks / Like
    Likes (Given)
    4991
    Likes (Received)
    3779

    Default

    There is a parameter to set whether the control looks for chuck open/close confirmation from proximity switches.

    If your machine doesnít have the prox switches for chuck cylinder stroke (a lot of Mazaks donít), then you have to set the machine parameter to disregard the prox switches, and use a timer for chuck open/close instead.

    Your parameter may be set to look for proz switch confirmation, and if you donít have prox switches, the control wonít know if the chuck is clamped or unclamped ó this could cause your interlocking issue.

    Also, there is a T parameter that you can set for the chuck open/close time (after you set the correct parameter to use chuck timer instead of prox switches).

    ToolCat

  2. #22
    Join Date
    Feb 2018
    Country
    UNITED KINGDOM
    Posts
    280
    Post Thanks / Like
    Likes (Given)
    106
    Likes (Received)
    77

    Default

    Hi ToolCat

    My machine does have the 2 proxy switches for open/close and chuck over stroke error (if it completely pulls the material out when bar pulling) so it is set to see that signal before it continues

    I tried it with that parameter turned off and the chuck still errors and stays closed and the bar pull sequence carries on but obviously can’t actually pull the bar even though it thinks it Has then carries On machining fresh air

  3. #23
    Join Date
    Feb 2018
    Country
    UNITED KINGDOM
    Posts
    280
    Post Thanks / Like
    Likes (Given)
    106
    Likes (Received)
    77

    Default

    Iím not sure about the T parameter though as my books only cover the R parameters so Iíd be interred to get a copy of the full parameter list

  4. #24
    Join Date
    Sep 2005
    Location
    il.
    Posts
    6,912
    Post Thanks / Like
    Likes (Given)
    49
    Likes (Received)
    1432

    Default

    i watched that vid several times, the led on CH flashes sometimes even before it latches in
    i think weak coil action on UCH relay
    could be
    low voltage
    failed device in line with coil (i don't have an electrical so i cant hazard to what that might be)
    poor path to OV (crappy or broken wire)
    instead of tapping it
    try just pushing in steady
    this would point at bad socket
    its something right there were you are tapping i think (unless of course its improper voltage to relay coil)

  5. #25
    Join Date
    Feb 2018
    Country
    UNITED KINGDOM
    Posts
    280
    Post Thanks / Like
    Likes (Given)
    106
    Likes (Received)
    77

    Default

    So today I had 2 new sockets fitted for UCH & CH and they also repaired what they said was some bad track but it still hasnít solved the issue!

    Does exactly the same as before

    Tomorrow Iím going to give it back to them to check over the entire board for track damage

    Thanks
    Marc

  6. #26
    Join Date
    Feb 2018
    Country
    UNITED KINGDOM
    Posts
    280
    Post Thanks / Like
    Likes (Given)
    106
    Likes (Received)
    77

    Default

    Voltage to coils reads 21v dc (coil is 24v dc) Could that be enough to do it?

    I fitted 2 new 110vac coil solenoids to the chuck/unchuck directional valve and I also tried new spark killers directly wired to the chuck/unchuck directional valve connectors but that made no difference and the relays still spark when switching?

    Problem still very annoying but hopefully Having someone Look at it later this week as the other cnc repair guy let me down

    So il wait and see what they can find if anything

    Thanks
    Marc

  7. #27
    Join Date
    Sep 2005
    Location
    il.
    Posts
    6,912
    Post Thanks / Like
    Likes (Given)
    49
    Likes (Received)
    1432

    Default

    i'm assuming your talking the 24vdc control voltage on the ice cube relays
    21 volts aint right
    every mazak control i've tried to trouble shoot was 24.somthing unless it was leaking to ground
    not sure if it is just the low voltage or the fact that something in the control circuit is bleeding to something else or what ever.
    i would definitely try to figure out what that is all about

  8. Likes cnctoolcat liked this post
  9. #28
    Join Date
    Sep 2006
    Location
    Abingdon, VA
    Posts
    3,775
    Post Thanks / Like
    Likes (Given)
    4991
    Likes (Received)
    3779

    Default

    Voltage to coils reads 21v dc (coil is 24v dc) Could that be enough to do it?
    I agree with wippin', the 24v has to be within +/-5% variance, at the most! The ice cubes probably won't close reliably on 21 volts.

    And I too have always measured 24.XX volts on the 24v circuits.

    Check your 24v power supply (or supplies, often there are 2 identical ones). There is an adjustment for voltage output, see if that gets you in range.

    Virtually any power supply on any cnc machine is suspect to fail after a couple decades, and these on the older Mazaks were definitely known to fail.

    On Edit: Meter the 24v traces on the pcb(s) from the relay sockets to the board connectors, then meter the cables and other stuff on out from the pcb connectors...

    ToolCat

  10. #29
    Join Date
    Feb 2018
    Country
    UNITED KINGDOM
    Posts
    280
    Post Thanks / Like
    Likes (Given)
    106
    Likes (Received)
    77

    Default

    I did meter the + & - from the little silver AVR unit which supplies the 24v DC above the relay boards, and measured at the terminals it was exactly 24 volts but as said when I measure across the diode mounted below the relay, think it’s an Back emf diode of some sort it’s only 21.2 bolts roughly

    I can’t see anything that allows me to adjust the voltage on the little AVR box unless it’s inside under the cover?

    Thanks
    Marc

  11. #30
    Join Date
    Sep 2005
    Location
    il.
    Posts
    6,912
    Post Thanks / Like
    Likes (Given)
    49
    Likes (Received)
    1432

    Default

    you got something in that line leaking to ground i'll bet
    or a high energy (lose, corroded or otherwise) connection pulling down that circuit

  12. #31
    Join Date
    Feb 2018
    Country
    UNITED KINGDOM
    Posts
    280
    Post Thanks / Like
    Likes (Given)
    106
    Likes (Received)
    77

    Default

    I’m very basic when it comes to electronics,

    Is there any guidance on where or how I’d start to see if anything on that pcb was leaking to ground?

    Thanks
    Marc

  13. #32
    Join Date
    Feb 2018
    Country
    UNITED KINGDOM
    Posts
    280
    Post Thanks / Like
    Likes (Given)
    106
    Likes (Received)
    77

    Default

    Ok

    So The dc voltage converter was putting out 24v exactly at the output terminals so I adjusted this to 25.3v at the terminals.

    The voltage adjustment did make a difference to some relays but not at all to others?

    There is only 1 dc power converter on the machine

    Going over the relays on the relay board the voltage seemed to be exact or too low in no particular area?

    So most relays were 25.2volts so only slightly under but the chuck & unchuck relays were still 21v - 22volts but so we’re a couple of others so it’s not a particular spot so they maybe fed from different tracks etc but would need tracing

    It’s not like I can hard wire the 24v dc to test it as they are only powered when switched so it won’t work to add 24v constant

    The relays are rated at 24v pick up 80% and drop out 30% so should still work in the 21/22volt range if not ideal shouldn’t they?

    Either way when the people come to look at it I will suggest this first about finding why I’m not getting the 24v to all relays

    Thanks
    Marc

    Thanks
    Marc

  14. #33
    Join Date
    Sep 2005
    Location
    il.
    Posts
    6,912
    Post Thanks / Like
    Likes (Given)
    49
    Likes (Received)
    1432

    Default

    i'd be more inclined to think the "leak" was machine side
    pinched wire
    corroded terminal strip
    lose connection
    if i had a dollar for every pinched blue wire that ruined my day id be retired already

  15. #34
    Join Date
    Sep 2005
    Location
    il.
    Posts
    6,912
    Post Thanks / Like
    Likes (Given)
    49
    Likes (Received)
    1432

    Default

    as far as how to trouble shoot this
    i would start disconnecting things in that same stream 1 wire at a time
    after every wire i would recheck the voltage
    at some point you are going to find which device is pulling down that circuit/trace/track as you call it


    or not
    thats the suck part about machine repair
    dealing with total failure
    a quality machine tool is good for 10 million cycles
    people just don't realize how quickly those millions of cycles pass
    after that every single one of the hundreds of devices on that machine is subject to failure
    so we just keep scratchin
    because that's what we have to do
    and when we find it we shake our fist at it and say "i caught you you fuck, now your mine."



    good luck


    wip

  16. Likes cnctoolcat liked this post
  17. #35
    Join Date
    Feb 2018
    Country
    UNITED KINGDOM
    Posts
    280
    Post Thanks / Like
    Likes (Given)
    106
    Likes (Received)
    77

    Default

    It goes beyond my capabilities to start trying to trace things and in depth fault finding so i had someone come in to look at it today from an electronics repair specialist 3 units down from me,

    He traced the signal for the relays back to the main pcl card and there is 2 specific chips, 1 for open and 1 for close, he reckons the next step should be these and about 10 capacitors also on the same board that he said should be changed because there cheap and easy to do and should be done while there purely because of how old it is,

    He checked a few other things but found nothing other than these chips which he finds suspect as the 2 relays for chuck open and close are also still getting 3 volts even when they should be off hence suspecting the bad main board chips

    Only downside is the chips are obviously very old and the only source now is somewhere like alliexpress from china which will take 2 - 3 weeks and probably longer with the covid stuff going on and the delays due to the run up to christmas

    BUT.....he said its a cheap start point for what the chips, capacitotrs and labour will cost thats where we will start

    I will keep you updated as and when this gets done and tested again but expect it to be a while

    Thanks
    Marc

  18. #36
    Join Date
    Sep 2005
    Location
    il.
    Posts
    6,912
    Post Thanks / Like
    Likes (Given)
    49
    Likes (Received)
    1432

    Default

    i've got alot of junk in the shed
    what "chips" are we talking about?

  19. #37
    Join Date
    Feb 2018
    Country
    UNITED KINGDOM
    Posts
    280
    Post Thanks / Like
    Likes (Given)
    106
    Likes (Received)
    77

    Default

    On 1 of the PLC boards, the wiring diagram just calls them Y07 & Y08 as seen in this picture

    bcb2d406-3905-4e27-ba1e-3e761f3c32e9.jpg

    I don’t have the actual chip part numbers I’m afraid but they have ordered them now anyway

    Thanks
    Marc

  20. #38
    Join Date
    Sep 2006
    Location
    Abingdon, VA
    Posts
    3,775
    Post Thanks / Like
    Likes (Given)
    4991
    Likes (Received)
    3779

    Default

    Wonder if your tech could de-solder a couple of similar chips that your machine doesn't use, then re-purpose them for your chuck open/close?

    Most boards are loaded with microchips, and lots of them aren't used because they are for options that the machine does not have.

    ToolCat

  21. #39
    Join Date
    Sep 2005
    Location
    il.
    Posts
    6,912
    Post Thanks / Like
    Likes (Given)
    49
    Likes (Received)
    1432

    Default

    i belive we are talking about solid state relays
    they are individually ran through that relay board
    you can use a different path simply by changing up the inputs and outputs
    kinda,
    if you know what i mean

    in a pinch you could bypass the device and just wire up an ice cube and socket next to it in the cabinet

  22. Likes cnctoolcat liked this post
  23. #40
    Join Date
    Feb 2018
    Country
    UNITED KINGDOM
    Posts
    280
    Post Thanks / Like
    Likes (Given)
    106
    Likes (Received)
    77

    Default

    The machine is still working so it’s not the end of the world, if I can’t solve the issue I will just live with it for what the machine costs me, and plod on with it, but hopefully new chips solve it

    The other issue I have is with the turret hydraulics sticking but I’m 99.9% sure that just requires a new directional valve but I’ve only managed to find one on eBay in America so with shipping it’s £280 nearly But not too bad for a fix


Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •