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Author Topic: Just got a lathe to retrofit  (Read 183506 times)

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Hood

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Re: Just got a lathe to retrofit
« Reply #120 on: March 18, 2007, 03:05:54 PM »
Thanks Wayne, have found these ones on Rapid http://www.rapidonline.com/productinfo.aspx?kw=inrush%20current&tier1=Electronic+Components&tier2=Filters+%26+Suppression&tier3=NTC+Inrush+Limiters&tier4=High+inrush+current+limiters&moduleno=61685
They have a 30Amp one but there are no specs so I am not sure of the voltage they can handle, maybe it doesnt matter?
Hood

Offline fdos

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Re: Just got a lathe to retrofit
« Reply #121 on: March 18, 2007, 04:08:28 PM »
It probably doesn't matter.   What you running the transformer from?   Is this a 3phase transformer?


Wayne....

Hood

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Re: Just got a lathe to retrofit
« Reply #122 on: March 18, 2007, 05:01:36 PM »
Yes its three phase, its the transformer out of the Bridgeport.
Hood

Hood

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Re: Just got a lathe to retrofit
« Reply #123 on: March 30, 2007, 04:37:16 PM »
Got the transformer wired up and working properly, getting 79.7V DC which should be OK for the Teknix drives. Tried to move the axis but if I click the MPG one notch the motors take off and I have to hit Reset, E-Stop or turn the MPG a bit more.
 If I  turn the MPG more than one notch the drives will fault out and the drive shows a solid red LED indicating out of position. Tried swapping the motor wires around but that only made it do exactly the same but in the opposite direction. Have a busy weekend ahead of me so dont think I will be able to mess around with the lathe but hopefully next week I can find the problem and get it moving properly, servos are new to me as I have only ever used steppers.

Hood

Offline fdos

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Re: Just got a lathe to retrofit
« Reply #124 on: March 30, 2007, 04:45:59 PM »
Hood.

Sounds like a typical encoder signal loss problem

Are you sure your encoders are wired correctly?   What encoders have you used?

Did you get any of the inrush current limiters?   HIf so how well have they worked for you?

Cor lot of "?" there lol..

Wayne....

Hood

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Re: Just got a lathe to retrofit
« Reply #125 on: March 30, 2007, 05:06:28 PM »
I think the encoders are wired correctly but will check up on that when I can get the time. They are US Digital encoders and I have the line drivers that convert them to RJ45, the Teknix drives as you know use RJ45 and I think the pinout is the same on both. I have the encoders running through the CNC Building Blocks breakout and cant remember seeing any jumpers for enabling the encoder pass through but I will do some reading to see what I can find.
 If I dont have a wiring problem and cant find a problem I will bypass the breakout and connect the encoders direct to the drives and see if that helps.

I didnt have to get the inrush limiters, I just had to connect the capacitors up correctly the caps only had a black dot on one of the terminals which I took to be positive but as usual I was wronggggggggggggggggggg!!!!!!!!!!!!!!!!! Had to get new rectifiers as they had blown along withthe fuses but the caps and everything else were still good.

Hood

Offline Chaoticone

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Re: Just got a lathe to retrofit
« Reply #126 on: March 30, 2007, 08:07:28 PM »
Hey Hood, I agree with Wayne, sounds like an encoder problem. This is one thing that makes servos superior to steppers. When you send the signal to turn the motor a set amount, the motor will push to get to that point. If it doesn't see the signal from the encoder, it thinks it hasn't reached it yet so , it keeps on pushing.

Glad there weren't any fireworks today. ;D

Brett
« Last Edit: March 30, 2007, 08:38:24 PM by Chaoticone »
;D If you could see the things I have in my head, you would be laughing too. ;D

My guard dog is not what you need to worry about!

Hood

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Re: Just got a lathe to retrofit
« Reply #127 on: March 31, 2007, 04:29:11 PM »
Wayne you were right I think, put a scope on the breakouts encoder outputs and dont get a trace but when on the breakouts encoder Inputs there is a nice trace. Seems like the encoder signal is not getting passed through the breakout. Not had a chance to check for correct wiring properly yet but initial checks it looked fine. Will check properly tomorrow if I get a chance and in the mean time I have mailed Ed at CNC Building Blocks to see if he can shed any light.

Brett
 Still no fireworks, thats three days now, must be a record for me ;)



Hood

Hood

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Re: Just got a lathe to retrofit
« Reply #128 on: April 12, 2007, 03:06:14 AM »
Not good news, spoke to soon when I said there were no fireworks LOL
 I was still having problems with the motors running away and have found out that the encoders are faulty, one is completely dead and the other has a very weak pulse, new internals on the way. Only problem now is my drives blew and I have been talking to Pete at CNC Teknix and eventually I asked him if my motors could be the prob as they are huge motors. Seems they are, the Teknix will drive them but will have to limit my accel which is not really what I want. Should have mailed before I bought with the motor specs and saved myself some heartache (and wallet ache ;) )
 Not sure how I am going to proceed as it all looks expensive from here as big drives are not in my price range.
 Will keep this updated when and if I have info.

Hood

Offline fdos

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Re: Just got a lathe to retrofit
« Reply #129 on: April 14, 2007, 07:12:19 PM »
Hood

Thats keyboard you are using I think is one of the Silicone ones?

What height are the keys?   I was thinking of buying a couple of those.

Taking the whole month off in May to try and get ahead with the Hardinge, it was just not happening with all the work I've had on recently.  Have to work 'kin hard this month to get May clear though!

Wayne....