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turmite
08-19-2003, 09:32 PM
Hi folks. I have reading and enjoying watch all of your progress in building your machines and I have finally started gathering parts.
I just bought three of these motors and I hope I didn't mess up big time. If anyone can give me some help as to power supply etc I would apprediate it. I got 500 count encoders instead of the ones listed on this quote. I play to go with Gecko drives and a
Mach 2 controller. My machine will be considerably heavier that most on here but I need the weight for a couple of reasons. One is to hole the spindle which is to be a 10 hp Colombo with automatic tool change. The motor weighs 62 lbs not counting the z axis and the tool and holder. X axis will carry the z axis and the y axis will carry a moving table and 4th axis rotary.

My two large axis will be using 1 .125 dia by 48" .200 pitch precision ball screws with double nuts. The x axis will be a .200 pitch but I don't know if my other ball screws are large enough in dia. at .500". I intend to install an air cylinder assist on the z axis.

Any hints or thought or formulas would be greatly appreciated. If you are interested in seeing what I will be making with this;


turmite

turmite
08-19-2003, 09:35 PM
oops I for the quote:

ReLiance DC servo motor micro 100 series
Nema frame 34
Back EMF Constant ke=68 v/kRPM
Torque constant kt=5.75 lb-in/Amp
Thats per amp of motor current
at 10 amps thats 57.5 lb-in=920 oz in
Rated peak torque 1080
the original encoders were 2048 line but I got 500 count

turmite

balsaman
08-19-2003, 11:00 PM
What's the voltage of those motors? They sound nice.

Eric

turmite
08-20-2003, 12:34 AM
Eric I didn't get the voltage. These are the motors that were on Ebay for so long that were selling 3 to a set and he never posted the voltage. I will email and try to find out. Wow after going back and reading my posts I realize I am more tired than I thought but late is the only time I really have to get on for very long.

Mike aka turmite

turmite
08-20-2003, 08:17 PM
Balsaman here is what the guy sent me.


Motor Voltage:
Maximum Terminal Voltage rating is 120 Volts DC.
You don't have to run that high if you don't want to.
You'll want to run at least 60 Volts on your supply for reasonable speed capability.
I'd recommend a 72 volt supply

turmite

HomeCNC
08-20-2003, 10:28 PM
With a 500 count encoder the Gecko 340 drive will work great!

turmite
08-20-2003, 10:49 PM
Thanks Jeff. PM sent.

Now can anyone head me in the right direction for a power supply??I don't even know where to start looking. The not so funny thing is, I graduated the Air Force school of electronics way back when and it is not like riding a bicycle! At one time I could write in binary now I can barely tell if they are 1's or 0's. That should tell you something about my age.

Any help will be appreciated.

turmite

balsaman
08-20-2003, 11:08 PM
A 48 volt transformer with a rectifier and a cap will make a ~67 volt powersupply. The problem is your motors are 10 amps, which is quite a bit. Maybe its best to make 3 smaller powersupplies. One for each axis.

I am sure Gecko 320 drives will work too. I think the 340's give you the ability to multiply the encoder pulses, if I am not mistaken. My encoders are 300 pulses per rev and work great with the 320's.

Eric

HomeCNC
08-21-2003, 12:41 PM
The higher the count the more you will need the 340 drive so you can change the count and bring it back down to something usable for the drive. My encoders are 250 CPR and that means with a .200 pitch screw you will need 5000 PPI. If you run 2:1 ratio then that's 10000 PPI. You can see that the higher you go the more powerful of a PC you will need.

turmite
08-21-2003, 03:46 PM
I see I didn't include the pc info. I will be running a Amd 1.3gig processer with 512 meg of ram and a 30-40 gig hard drive. It has Win. NT 2000 Pro. for the os but I am nt sure I like it as much as I do xp. I am by no means a computer guy as I barely know how to turn one on but I sure am having fun learning. The thing I have noticed between the two computers I have, one with xp the other with 2000, is that the 2000 is way slower now that it was when I had 98 installed. I only have 256 ram currently so maybe the 2000 is enough more program that is has slowed down a lot. Help here would be appreciated too. The board I am using can take sd ram or ddr ram and currently has sd. It can hold up to 1.1gig of ram but I don't think I would need anything like that would I. My current machine old and slow has been shutting down the past two because of file sizes but we are talking dx2-66 cpu small hard drive and 128 m of ram. I am going to have to speed the process up though and may retrofit the existing machine whil build the frame of the new machine. Help!

turmite

balsaman
08-21-2003, 05:00 PM
Go with the 340 drives (as suggested by Jeff) and the mach 1 software. Anything over 500 mhz with 128 mb ram will be fine. Another option is Turbocnc (dos) with your 66 mhx machine.

Eric

turmite
08-21-2003, 08:12 PM
Jeff why the mach1 rather than the mach2?

balsaman
08-22-2003, 01:19 AM
Mach2 is a beta, when it's ready it will be a free upgrade to mach1

Eric

turmite
08-22-2003, 02:03 AM
balsaman would either of these work?


I have a 48 volt REGULATED power supply on hand. It is rated at a whopping 35 amps. Price is $249, which is a great deal.

I can get 60 volt unregulated supplies, and they are going for $159

turmite

kong
08-22-2003, 08:31 AM
It may pay you to have a look on ebay, I just scored a 24v 25Amp PSU for a mere 30 GBP. Dunno if you've looked or not already, just a thought.

balsaman
08-22-2003, 09:55 AM
No need for a regulated supply. I wouldn't go with only 48 volts. Go with the 60. A little higher would be even better (up to around 70) but not neccesary I don't think.

Eric

HomeCNC
08-25-2003, 12:24 PM
Be aware of Mach 1. Art told me that it is not programmed per standard for the USA. I guess he had many UK users telling him to change things so it does not follow the same tool change method and other things. Mach 2 has been changed to follow the controller standard for machining. mach 2 is at release canidate 2 now. I did a review of it when it was at beta 12. Look in the review area on this board.