Page 11 of 25 FirstFirst ... 91011121321 ... LastLast
  1. #101
    Chaz's Avatar
    Lives in Ickenham, West London, United Kingdom. Last Activity: 17 Hours Ago Has been a member for 4-5 years. Has a total post count of 973. Received thanks 69 times, giving thanks to others 42 times.
    Quote Originally Posted by Clive S View Post
    Neutral is not earth In the UK the earth is bonded to the neutral in most cases but not always.
    The ground in your case is a central point where all the screens and ground are connected together in one place (star point) and that point in connected to the general earth connection. This is to try and stop ground loops. ..Clive
    Ah, sorry, mistook 'star point' as the star of a 3 phase system which is commonly earthed. Thanks, understood what you explained.

    Out of interest, my drawings show the encoder shield only being attached on side and from speaking to a colleague this morning, that seems common practice (not to earth both sides of a shield). Would that be correct based on the collective experience here?

  2. #102
    Out of interest, my drawings show the encoder shield only being attached on side and from speaking to a colleague this morning, that seems common practice (not to earth both sides of a shield). Would that be correct based on the collective experience here
    Yes that would be correct. Clive

  3. The Following User Says Thank You to Clive S For This Useful Post:


  4. #103
    Been away for the past week (my Golden wedding aniversary celebrations?), so sorry to be harping back to one of the non technical points. If your motor is marked as 230v 3 ph you can almost certainly run that coolant pump on single phase. Set the motor block connecters to Delta and either use a vfd or trick the motor to run in quasi 3 phase using a couple of caps. I have been running 3ph motors on 230v single phase for over 20 years and have never had any problems. It may be neccessary to use a separate switched cap for starting. If in any boubt, cap values etc. you can PM me. Your project is looking great. Well done. G.

  5. #104
    Chaz's Avatar
    Lives in Ickenham, West London, United Kingdom. Last Activity: 17 Hours Ago Has been a member for 4-5 years. Has a total post count of 973. Received thanks 69 times, giving thanks to others 42 times.
    Quote Originally Posted by GEOFFREY View Post
    Been away for the past week (my Golden wedding aniversary celebrations?), so sorry to be harping back to one of the non technical points. If your motor is marked as 230v 3 ph you can almost certainly run that coolant pump on single phase. Set the motor block connecters to Delta and either use a vfd or trick the motor to run in quasi 3 phase using a couple of caps. I have been running 3ph motors on 230v single phase for over 20 years and have never had any problems. It may be neccessary to use a separate switched cap for starting. If in any boubt, cap values etc. you can PM me. Your project is looking great. Well done. G.
    Thanks. I did buy a starting cap from Maplins on the weekend. Need to get to the point that I can install it. This is what I bought,
    2.5F 440V Motor Run Capacitor


  6. #105
    You probably need a starting cap and a run cap. I actualy use a little timer that switches the start cap in for about one second, but the value of the caps you use is dependant on the motor power and if the motor is stating under load etc.. This system does not give a true 3ph, but a "quasi" 3ph, however for a coolant pump I am sure it that you will never know the difference. G.

  7. #106
    Chaz's Avatar
    Lives in Ickenham, West London, United Kingdom. Last Activity: 17 Hours Ago Has been a member for 4-5 years. Has a total post count of 973. Received thanks 69 times, giving thanks to others 42 times.
    What is the general consensus for wiring the Emergency Stop Relay. Keep this and its function (X Y Z extreme limits) or wire into the CS Labs directly and control from there?

    Currently on activation it stops all drives, the spindle, the coolant pump and the ATC. It works and I am inclined to leave it in place as it is.

  8. Keep it as is, but feed an output from the relay into an input on the controller to tell it you have an estop state.

    Quote Originally Posted by Chaz View Post
    What is the general consensus for wiring the Emergency Stop Relay. Keep this and its function (X Y Z extreme limits) or wire into the CS Labs directly and control from there?

    Currently on activation it stops all drives, the spindle, the coolant pump and the ATC. It works and I am inclined to leave it in place as it is.

  9. The Following User Says Thank You to Gary For This Useful Post:


  10. #108
    Quote Originally Posted by Chaz View Post
    What is the general consensus for wiring the Emergency Stop Relay. Keep this and its function (X Y Z extreme limits) or wire into the CS Labs directly and control from there?

    Currently on activation it stops all drives, the spindle, the coolant pump and the ATC. It works and I am inclined to leave it in place as it is.

    Well I don't agree with Killing power because Limit trip isn't an emergency situation it's a positional error so no need to Kill power just Halt movement. SO I would have limits tied to the Enable signal on drives and Inform the Controller of a Limit breach.
    This way you don't damage expensive tooling when the spindle grinds to halt inside of material because power is Cut.! Machine is just halted from continuing and you can recovery safely by lifting tooling out of material then reversing off the Switches using tempory overide.

    E-stop is an emergency situation to the operator and this is when you want power stopped but often positional errors ie: limits are not life threatening or dangerous to user only potential machine damage and the Limit's prevent this in most cases.

    I did wounce upon time think "Kill every thing" but experience as taught me it's not needed where limits are concerened and it's more a pain in the arse, esp with short travels with fast accelerating machine and expensive at times with unnecessary tool damage.
    Last edited by JAZZCNC; 22-06-2015 at 10:52 PM.

  11. #109
    m_c's Avatar
    Lives in East Lothian, United Kingdom. Last Activity: 11 Hours Ago Has been a member for 9-10 years. Has a total post count of 1,831. Received thanks 192 times, giving thanks to others 5 times.
    Quote Originally Posted by GEOFFREY View Post
    You probably need a starting cap and a run cap. I actualy use a little timer that switches the start cap in for about one second, but the value of the caps you use is dependant on the motor power and if the motor is stating under load etc.. This system does not give a true 3ph, but a "quasi" 3ph, however for a coolant pump I am sure it that you will never know the difference. G.
    One thing to be aware of when using this method, is you have to select caps that will provide reasonably matched voltages between the 3 legs when running. Achieving that with a small motor may prove to be a bit of a challenge, but you should benefit from the fact a coolant pump should have a reasonably steady load.
    My main concern would be that the coolant pump motor is running near it's rated capacity, and when running from a static phase converter you risk burning out the motor if you try running it at high loads.
    Avoiding the rubbish customer service from AluminiumWarehouse since July '13.

  12. With a servo system cutting the power to the drivers if limits are activated is for safety in case you have a servo run away due to encoder loss, but cutting the enable will also work in this situation as well.


    Quote Originally Posted by JAZZCNC View Post
    Well I don't agree with Killing power because Limit trip isn't an emergency situation it's a positional error so no need to Kill power just Halt movement. SO I would have limits tied to the Enable signal on drives and Inform the Controller of a Limit breach.
    This way you don't damage expensive tooling when the spindle grinds to halt inside of material because power is Cut.! Machine is just halted from continuing and you can recovery safely by lifting tooling out of material then reversing off the Switches using tempory overide.

    E-stop is an emergency situation to the operator and this is when you want power stopped but often positional errors ie: limits are not life threatening or dangerous to user only potential machine damage and the Limit's prevent this in most cases.

    I did wounce upon time think "Kill every thing" but experience as taught me it's not needed where limits are concerened and it's more a pain in the arse, esp with short travels with fast accelerating machine and expensive at times with unnecessary tool damage.

Page 11 of 25 FirstFirst ... 91011121321 ... LastLast

Similar Threads

  1. FOR SALE: Denford Triac CNC PC
    By ricey3 in forum Items For Sale
    Replies: 6
    Last Post: 10-01-2017, 01:39 PM
  2. Help Denford triac p.c.
    By mikeulike in forum Denford Mills
    Replies: 3
    Last Post: 02-06-2015, 03:59 PM
  3. eBay: Denford Triac with Mach3 Conversion
    By large519 in forum Items On eBay UK
    Replies: 0
    Last Post: 29-04-2015, 05:34 PM
  4. CONVERSION: Denford Triac Mach3 conversion
    By rnr107 in forum Conversion Build Logs
    Replies: 11
    Last Post: 23-10-2014, 02:44 PM
  5. WANTED: Denford Triac
    By edwardsjc in forum Items Wanted
    Replies: 13
    Last Post: 20-08-2012, 08:17 AM

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
  •