Where to buy a 24dvc power supply with..

[cpcapace]

Where have all of you purchased your 24 vdc power supplies that can supply 6amp which I what it seems I'll at least need for my 3 axis motors.

Thanks!

P.S.

What do you think about this 3 axis board, and has any had experience. The seller seems to have a good feedback.

http://cgi.ebay.com/3-AXIS-CNC-ROUTE...3A1%7C294%3A50

[dertsap]

Originally Posted by cpcapace What do you think about this 3 axis board, and has any had experience. The seller seems to have a good feedback. http://cgi.ebay.com/3-AXIS-CNC-ROUTE...3A1%7C294%3A50

you'd be better off buying gecko rather than buying something off ebay that probably wont work , you get what you pay for http://www.geckodrive.com/products.aspx?n=764794

[amplexus]

A linnear 24 volt power supply is very easy to build, but if you think you need 6 amps design for at least 12, it is always good to have some headroom about all you need is a transformer, bridge rectifer and voltage regulator for a single sided supply, for double sided you need a tapped transformer and duplicate circutry. just search the web for power supply schematics. Switchers may be over your skill level but there are tons of them on the web. With a different choice in steppers you may be able to use an old computer power supply.
amplexus

[blue_steel]

I use this one with my L297/298 drivers. The price was right and it's at least good enough to get me going.

You might be able to find this same model on ebay for a few dollars cheaper.

http://www.mpja.com/prodinfo.asp?number=17429+PS

[cpcapace]

I was thinking about usings pc power supply, but I want a little more voltage.

I'm thinking about getting this kit from cnchobby.com

$265 for 3 Axis Package w/ (3) 305oz-in 4.2V 3A Steppers. My machine is pretty small. I've made the basic setup. 3 axis. (20" x 18"

Made from mdf and aluminum. I'm going to be using 1/20 inch rods(1/25d).

I'm going to be using my dremil.

I'll post pictures soon.

Any think the gecko drive would be better?

[dertsap]

1/2"-20 is too high a resolution , i would use at least 1/2-10 acme to move your router other than that it will be painfully slow
you can always daisychain pc supplies to get higher voltage

[radcliffe]

The link is a switching supply 24vdc 12.5A. I have two of these, one to run the hot wire stepper and the othe to heat the wire. Price $24.95
http://www.mpja.com/prodinfo.asp?number=17429+PS

Harold

[amplexus]

The gekko controllers are great but expensive. Consider building you own around this chip A3986
Dual Full-Bridge MOSFET Driver with Microstepping Translator
Features

* 2-wire step and direction interface
* Dual full-bridge gate drive for N-channel MOSFETs
* Operation over 12 to 50 V supply voltage range
* Synchronous rectification
* Cross-conduction protection
* Adjustable mixed decay
* Integrated sinusoidal DAC current reference
* Fixed off-time PWM current control

Description

The A3986 is a dual full-bridge gate driver with integrated microstepping translator suitable for driving a wide range of higher power industrial bipolar 2-phase stepper motors (typically 30 to 500 W). Motor power is provided by external N-channel power MOSFETs at supply voltages from 12 to 50 V.

This device contains two sinusoidal DACs that generate the reference voltage for two separate fixed-off-time PWM current controllers. These provide current regulation for external power MOSFET full-bridges.

Motor stepping is controlled by the two-wire step and direction interface, providing complete microstepping control at full-, half-, quarter-, and sixteenth-step resolutions. The fixed-off time regulator has the ability to operate in slow-, mixed-, or fast-decay modes, which results in reduced audible motor noise, increased step accuracy, and reduced power dissipation.

The translator is the key to the easy implementation of this IC. Simply inputting one pulse on the STEP input drives the motor one step (full, half, quarter, or sixteenth depending on the microstep select input). There are no phase-sequence tables, high frequency control lines, or complex interfaces to program. This reduces the need for a complex microcontroller.

The above-supply voltage required for the high-side N-channel MOSFETs is provided by a bootstrap capacitor. Efficiency is enhanced by using synchronous rectification and the power FETs are protected from shoot-through by integrated crossover control and programmable dead time.

In addition to crossover current control, internal circuit protection provides thermal shutdown with hysteresis and undervoltage lockout. Special power-up sequencing is not required.

. the app notes tell you everything you need and if you need more current you can always upgrade the fets, best of all no fast diodes needed if you follow the ap note plans, just pay attention to power trace and sense layout.
you can find this on another thread in the forums
very cool
Amplexus

[steve323]

Originally Posted by dertsap you'd be better off buying gecko rather than buying something off ebay that probably wont work , you get what you pay for http://www.geckodrive.com/products.aspx?n=764794

I agree that the geckos are probably the best choice, although they are a bit more expensive. I would have definately gone that route if the 540s were avalaible when I built my system.

The HobbyCNC controller is probably a better option that the Ebay controller. The 3 axis version is only $79, although you do need to solder it yourself. It has a lot of happy owners (myself included). HobbyCNC is 3A per phase unipolar only, slightly less power than 2.5A per phase bipolar.

Steve

[amplexus]

Ignre what I said about the the A3986, the documentation neglects to mention it misses steps in microstep mode and they are unwilling to fix it. However there are other chips out there that do not have this problem, look around on the forums and you will find a schematic that will work for you. Try this, the 297/98 combo. you can remove the 298 and use a 74aco8 and 4 FET,s have a look at www.pchilton.co.uk/images/stepperdriver.jpg I have used IRF50N06 plus FR304 diodes he used IRL640 as it is a 200 volt device with out diodes. i have read of people using two
298 in parallel but this is still not enough for what you want to do.
Hope this may help, Michael an eccentric English man.
P.S. or a 74HC08

amplexus