584,814 active members*
5,169 visitors online*
Register for free
Login
Page 1 of 2 12
Results 1 to 20 of 24
  1. #1
    Join Date
    Jan 2011
    Posts
    68

    Teknic Servo drive Power supply

    I thought I had already posted a thread but I guess not or maybe it was removed for some reason? Anyhow I have a Omnibeam laser machine that uses Teknic servo drives and motors. The Power supply unit for the server drivers was built by coherent and consisted of transforms, rectifiers and some caps. One of the transformers had a short and is damaged and I have not been able to find any replacement units. About the only specs I can find are that they are 240v pri and are wired up with two input and two output wires. The input is 3 phase and output seems to have been 50vac. The size and weight leads me to believe the transformers are around 200va units and there are 3 of them. If my thinking is correct a watt is a watt right? So if there are 600va total in transformers with losses the most this unit could provide would be just shy of 500 watts correct? This is confusing as this machine has 4 of these teknic motors and drives and they are rated at 9.5amp cont. and 9.5x70vdc is 665 watts which is already greater than the whole bank of transformers could even provide. Anyhow long story short, i want to remove this coherent made power unit and replace it with two 420 watt 3 phase Linmot power supplies that are designed for servo drives. If my thinking it right having 840 watts of total output would be sufficient for this system if before it only had about half that. What am I missing or is this somewhat accurate? Below is the power unit in the machine.

    Servo and drives are Teknic M-3421C-LN-20DG Servo motors with Teknic Eclipse SST-E545-RCX-4-2-D Servo Drives.

    Any help with this would be fantastic. I

    Thanks
    Mike

  2. #2
    Join Date
    Jan 2018
    Posts
    1516

    Re: Teknic Servo drive Power supply

    (copy this into google search) SST-E545-RCX-4-2-D pdf

    Should give you the data sheet for the servo drive series as top result.
    It actually shows they have 2 inputs on the drive for 24-90DC input by the looks of it.

    If this is correct I reckon I'd go 70vdc with between 800-1000w in total.
    I always go as close as safely possible to a drivers max voltage to guarantee good motor velocity.

  3. #3
    Join Date
    Jan 2011
    Posts
    68

    Re: Teknic Servo drive Power supply

    I am not seeking to improve on the machine performance just simply want to replace the damaged 3ph toroidal transformer power supply with a more available off the shelf unit of some kind. The Original toroidal transformer power supply provided 70vdc to the 4 Teknic drivers but I have no idea what the specs of the power supply other than its a 3ph setup. I was just coming up with on logic that if these are 200va transformer and there are 3 of them then I have a total of 600va available right? So if I use two 420va power supplies to replace the original unit then I should be good to go right? The Units I am looking at are 420va 72vdc out 3ph 240v input. At this point I just want to match or at least go over the original power supply VA to make sure I do not cause anything to lack the power it needs.

  4. #4
    Join Date
    Dec 2013
    Posts
    5717

    Re: Teknic Servo drive Power supply

    If it were my machine I would use one of these, not 3 phase but that is not really required. I've used these in a couple of installations with good results.

    https://www.automationtechnologiesin...pplies/kl-7220
    Jim Dawson
    Sandy, Oregon, USA

  5. #5
    Join Date
    Jan 2011
    Posts
    68

    Re: Teknic Servo drive Power supply

    I have considered using only single phase but I wonder if pulling a load off only the single phase lines would effect the voltage to the 3ph DC power supply for the laser itself. The servo drive portion on this machine is a light load compared to the load the Laser demands.

  6. #6
    Join Date
    Dec 2013
    Posts
    5717

    Re: Teknic Servo drive Power supply

    Quote Originally Posted by Mike Hall View Post
    I have considered using only single phase but I wonder if pulling a load off only the single phase lines would effect the voltage to the 3ph DC power supply for the laser itself. The servo drive portion on this machine is a light load compared to the load the Laser demands.
    Not of the wiring is large enough to prevent substantial voltage drop. A slightly unbalanced input should not have any effect, it will most likely not cause anymore unbalance than you normally see on the mains under normal conditions.
    Jim Dawson
    Sandy, Oregon, USA

  7. #7
    Join Date
    Jan 2011
    Posts
    68

    Re: Teknic Servo drive Power supply

    While reading up on this apparently with a machine like this which is high speed and accelerates and decelerates often there may be regeneration of up to 95v being sent back to the power supply. It stated that all components would have to be 100v rated to keep from being damaged. those power supplies from them have 80v caps so they would possible be damaged by the higher voltages. This original power unit has all 100v caps so it is making sense that this machine may have seen reg voltages with how it operates. The Power supplies I am wanting to use are Linmot 420VA class 3 phase units which have an RMS output of 72v 5.8amps. In my mind the logic seems to say that's not enough but two of these units should have greater capacity than the one unit that was on the machine.

  8. #8
    Join Date
    Dec 2013
    Posts
    5717

    Re: Teknic Servo drive Power supply

    Those Linmot units are spendy. But should work OK.

    Replacing the caps in the Automation Tech unit would be cheaper.
    Jim Dawson
    Sandy, Oregon, USA

  9. #9
    Join Date
    Jan 2011
    Posts
    68

    Re: Teknic Servo drive Power supply

    Quote Originally Posted by Jim Dawson View Post
    Those Linmot units are spendy. But should work OK.

    Replacing the caps in the Automation Tech unit would be cheaper.

    Yes those Linmot units are but I found some local that I could pick up pennies on the $. The thing I would like to understand is how 600va is able to supply 4 Tiknic servo motors the power they need with they are rated at 9.5amp 72v RMS. My math must be way off or I am missing something. And if in fact this machine originally had 600va of power available then 840va would work no problem. The Linmot units are designed with the high voltage generation issues, their manual is where I was reading up on that issue. So not considering cost would the two 420va Linmot units be sufficient for this machine?

  10. #10
    Join Date
    Dec 2013
    Posts
    5717

    Re: Teknic Servo drive Power supply

    Quote Originally Posted by Mike Hall View Post
    Yes those Linmot units are but I found some local that I could pick up pennies on the $. The thing I would like to understand is how 600va is able to supply 4 Tiknic servo motors the power they need with they are rated at 9.5amp 72v RMS. My math must be way off or I am missing something. And if in fact this machine originally had 600va of power available then 840va would work no problem. The Linmot units are designed with the high voltage generation issues, their manual is where I was reading up on that issue. So not considering cost would the two 420va Linmot units be sufficient for this machine?
    The dirty little secret is that for the most part servo drives operate at a small fraction of their rated power 95% of the time. With only occasional momentary excursions to max rated power under hard acceleration conditions. That's why you can get away with a power supply that is rated lower than the sum of all of the drives. Linear power supplies have an amazing momentary overload capacity.

    I have two 750W dc servos and a 6.3A stepper on my mill, and I run it all on a 70V, 5 A supply with no problems at all. I have never run out of power.
    Jim Dawson
    Sandy, Oregon, USA

  11. #11
    Join Date
    Jan 2011
    Posts
    68

    Re: Teknic Servo drive Power supply

    I figured this would be the case but I wanted someone with more knowledge to make that clear. There is a lot to consider when dealing with these drives and motors but my whole logic is 600va available from the start then 840va should be even better. haha Thank you for your input, I am about to go get these Linmot units for a steal. I will update as I get things installed.

  12. #12
    Join Date
    Jan 2011
    Posts
    68

    Re: Teknic Servo drive Power supply

    I just got home from picking up these Linmot power supplies and they are just barely going to fit with a custom bracket I will make. It will be tight but it will work. One question though, these are putting out almost 85vdc each, they are rated at 72vdc. What is the deal with this? Max voltage for the Teknic servo drivers is 90vdc and I sure do not want to run into damaging one of them. These units have 3 different inputs 220v/230v/240v. I am getting more like 248v/252v/248v out of my phase converter, is this an issue?

  13. #13
    Join Date
    Dec 2013
    Posts
    5717

    Re: Teknic Servo drive Power supply

    That is a bit high, but not uncommon. My shop voltage used to run 249 to 252 until the power company changed out the transformer, now it's down to around 238 to 242.

    Once under some load the voltage output of the power supplies will drop a bit, they tend to run on the high side until there is some load on them. I'm not sure how sensitive the Technic units are to overvoltage. Connect a 60W light bulb across the power supply output and see what the voltage is. If you can actually find a 60W light bulb
    Jim Dawson
    Sandy, Oregon, USA

  14. #14
    Join Date
    Jan 2011
    Posts
    68

    Re: Teknic Servo drive Power supply

    Ok I will give that a try. I may have an old 60watt bulb in the shop somewhere.

    I have made an aluminum bracket to mount these units to but man they are bigger than I was thinking. I really needs a single 600va unit for it to fit nicely in the original area. I may scrap using these and try to find a suitable 3phase 600va unit which would be much easier to fit. The issue is most all the 600va units are 400v + input and I do not see a way around that. It sucks being many of those units are dirt cheap and brand new....

  15. #15
    Join Date
    Jan 2011
    Posts
    68

    Unhappy Re: Teknic Servo drive Power supply

    I am curious, what happens if you input 240v 3phase into a transformer that is designed for 400v 3phase? Would the output just be less or would it not have any output at all? There are so many 400v 3 phase units for great deals it makes me sick knowing I can not use any of them..

  16. #16
    Join Date
    Jan 2011
    Posts
    68

    Re: Teknic Servo drive Power supply

    Well I have no idea how I did not come across this before. It look like the IPC-5 power supply from Teknic would support my Servo drive setup and it is only a 350 watt power supply. That being said one of these Linmot power supplies would be plenty for this machine if that is the case. I understand that like the specs say on the teknic chart that use will heavily determine what power supply is used or how many drives cane be powered off one power supply. Any thoughts on this? The linmot power supplies I have are slightly lower voltage but provide more amps than the ICP-5 from Teknic. The ICP-5 normally powers between 2-6 drives depending on setup and my drives are in the list.
    Attached Thumbnails Attached Thumbnails Teknic info 1.PNG   Teknic ipc 5.jpg  

  17. #17
    Join Date
    Dec 2013
    Posts
    5717

    Re: Teknic Servo drive Power supply

    Quote Originally Posted by Mike Hall View Post
    I am curious, what happens if you input 240v 3phase into a transformer that is designed for 400v 3phase? Would the output just be less or would it not have any output at all? There are so many 400v 3 phase units for great deals it makes me sick knowing I can not use any of them..

    It would output less voltage at the ratio of 240/400 = 60% of the rated output voltage. The power would also be derated.
    Jim Dawson
    Sandy, Oregon, USA

  18. #18
    Join Date
    Dec 2013
    Posts
    5717

    Re: Teknic Servo drive Power supply

    Quote Originally Posted by Mike Hall View Post
    Well I have no idea how I did not come across this before. It look like the IPC-5 power supply from Teknic would support my Servo drive setup and it is only a 350 watt power supply. That being said one of these Linmot power supplies would be plenty for this machine if that is the case. I understand that like the specs say on the teknic chart that use will heavily determine what power supply is used or how many drives cane be powered off one power supply. Any thoughts on this? The linmot power supplies I have are slightly lower voltage but provide more amps than the ICP-5 from Teknic. The ICP-5 normally powers between 2-6 drives depending on setup and my drives are in the list.

    As said, in most cases drives are only using a fraction of their rated power and rarely do two or more require full power at the same time. So you can get away with a smaller power supply and the raw numbers would indicate. If I were building a panel for a customer, I might go with about 60% of the sum of the power of all the drives, again depending on the application. For myself, I would go maybe a bit less, maybe only enough to power one drive at full power continuously. I use servo motors in applications other than motion control applications. So many times I know I'll only be using a small fraction of the rated power output.
    Jim Dawson
    Sandy, Oregon, USA

  19. #19
    Join Date
    Jan 2011
    Posts
    68

    Re: Teknic Servo drive Power supply

    I pulled a late one and got the new power supply and E stop contacts mounted and everything wired up. I ran the machine for a bit seeing if I could produce some very high amp draw and the highest amp draw I could manage to make it pull is 8.86 amps and that is mostly because of the Z axles which raises the bed. The Secondary output of this power supply is fused at 15 amps so I should be safe or at least I hope so. I am pleased with the install and I hope this unit proves to be enough for the machine in the long run. Thanks for the help so far.
    Attached Thumbnails Attached Thumbnails 20220107_032945.jpg   20220107_033649.jpg  

  20. #20
    Join Date
    Jan 2011
    Posts
    68

    Re: Teknic Servo drive Power supply

    Just an update with a question as well. I have been running the machine more and have run into some Servo drive errors with the Y axis motors when the gantry is moved back to the far side of the machine. I thing I have sorted this out with getting the belt tension matched better between the two but still have the issue if the machine accelerates from that rear area of the machine.

    My question is about the Linmot power supply i installed. It is putting out 82v (250v input) where it should only be outputting 72v. I have noticed that with running some files I have gotten a peak amp draw of almost 11amps which may be only a spike as I have not see it draw that continuously. I also set the meter to record the lowest voltage while operating the machine and 76v is as low as I have seen it drop. The issue is this is a 5amp power supply which I guess is RMS continuous power so should I be concerned with the spikes up above double the rated RMS output? I was looking into this thinking maybe it was a power issue causing the servo faults (with HORRIBlE vibration and noise). I see the Power supply can provide 15amp at 15% ED. I am not all that verses on motor/drive/power supply specs but it seems that has something to do with duty cycle and may need to be matched to the motors/drives I am using?

    here is a short video of doing some test cutting

    https://youtu.be/bgy-3WWN4Sk

Page 1 of 2 12

Similar Threads

  1. Teknic IPC-5 Power Supply - Fan mounting
    By bobmagnuson in forum DIY CNC Router Table Machines
    Replies: 3
    Last Post: 05-22-2018, 08:12 PM
  2. Rectifier for Ajax AC/DC Servo Drive (30 Amps) power supply
    By howanc7 in forum CNC Machine Related Electronics
    Replies: 12
    Last Post: 02-05-2014, 11:00 PM
  3. Rectifier for Ajax AC/DC Servo Drive (30 Amps) power supply
    By howanc7 in forum CNC Machine Related Electronics
    Replies: 0
    Last Post: 01-21-2014, 07:24 AM
  4. teknic sst 3000 servo drive
    By john.charles in forum Servo Motors / Drives
    Replies: 0
    Last Post: 12-20-2010, 07:28 PM
  5. Dynapath 10 replace servo drive & power supply??
    By ken fedirko in forum DNC Problems and Solutions
    Replies: 3
    Last Post: 01-13-2008, 12:30 AM

Tags for this Thread

Posting Permissions

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