Need Help!- cnc router stepper motors

[ncrncevic]

Hello
i would build a cnc router and i bought this

http://cgi.ebay.com/3-linear-rails-S...item3a5ce19399

Can you give me some advice for a cnc stepper kit froam ebay

for a motor i would buy this

http://cgi.ebay.com/water-cooled-spi...item3a5aa000b0

i would worked with aluminum and some stainless steel timber on the cnc

[giveinfo]

KelingINC have good KIT for you

http://www.kelinginc.net/CNCNEMA23G540Package.html

I bought one from them so i recommend them.

Don't buy cheap **** electronic from Ebay because you will have just problems!

PS. imas pp na elektronika.ba

[Crevice Reamer]

This one:

G540 3 axis package (One G540 + Three
KL23H2100-35-4B (1/4” Dual shaft with a flat) 381 oz-in + one KL-
350-48 48V/7.3A 115V /230Vpower supply: $455.95

If you need 4 motors, just add another 381. This PSU is adequate for all four.

http://crevicereamer.com/Page__57.html

CR.

[Jason Marsha]

CR,
Not sure if 7.3 amps will run 4 of those motors, but I see Keling is now offering this kit with the 12.5 amp power supply

G540 4 axis package (one G540 + Four KL23H2100-35-4B( 1/4” Dual
shaft with a flat) 381 oz-in + one KL-600-48 48V/ 12.5A 115V /230V
power supply): $574.95

Jason

[Crevice Reamer]

Originally Posted by Jason Marsha CR, Not sure if 7.3 amps will run 4 of those motors, but I see Keling is now offering this kit with the 12.5 amp power supply G540 4 axis package (one G540 + Four KL23H2100-35-4B( 1/4” Dual shaft with a flat) 381 oz-in + one KL-600-48 48V/ 12.5A 115V /230V power supply): $574.95 Jason

Yes, that DOES seem logical, but the G540 has an internal 7A fuse.
http://search.digikey.com/scripts/Dk...&name=F2318-ND

That means 7A is the MAX Amps available to 4 motors regardless of PSU Amp rating. If G540 tried to draw more than 7A, the fuse would blow.

Ergo: All PSU Amps over 7 are wasted money.

CR.

[Jason Marsha]

So the G540 cannot really push these motors to max potential.
I might have to consider 4 single drives then

Thanks CR (I think I saw a comment about the 7amp fuse before but I forgot about it)

Jason

[Crevice Reamer]

Originally Posted by Jason Marsha So the G540 cannot really push these motors to max potential. I might have to consider 4 single drives then Thanks CR (I think I saw a comment about the 7amp fuse before but I forgot about it) Jason

Not true. The G540 CAN push four 3.5A motors to fullest potential. It is DESIGNED to do exactly that. You have to understand that PULSED DC is a whole different Amperage than STEADY DC.

CR.

[Jason Marsha]

Four motors at 3.5 amps = 14 amps

I remember something about 2/3 of total = approx 9.4 amps

Say the machine is cutting 3D work i.e all motors moving constantly how do the motors get the total required current to push them?

(If Mariss explained how this works post a link so I do not hijack this thread)

Jason

[Crevice Reamer]

Originally Posted by Jason Marsha Four motors at 3.5 amps = 14 amps I remember something about 2/3 of total = approx 9.4 amps Say the machine is cutting 3D work i.e all motors moving constantly how do the motors get the total required current to push them? (If Mariss explained how this works post a link so I do not hijack this thread) Jason

PULSING DC draws less total Amperage than steady DC. If you hook up an Ammeter to a 3.5A stepper, and then run it at max, The Ammeter will NOT read 3.5A, but something less.

Think of Amperage as water through a hose. At a fixed pressure, (Steady DC) a steady stream of water through the hose will fill a bucket in so many minutes.

If you then start and stop the flow of water with the valve, (pulsing) it will take many MORE minutes to fill the bucket, even though the pressure stays constant.

Same with pulsed Amperage. The G540 is designed (unlike many OTHER drivers) to reliably deliver its maximum performance. It does not need to be detuned. It is designed for max operation of four 3.5A steppers at 50V and that's what you get. Seven pulsed Amps is PLENTY for all four steppers at once. If it weren't, then Mariss would have installed a larger fuse.

CR.

[Jason Marsha]

Thanks CR, as long as I can still use the G540 I am happy, I though I had to scratch the G540 from the upcoming setup.

Jason

[ncrncevic]

One more question


if i buy this

G540 4 axis package (One G540 + Four
KL23H284-35-4B (1/4” Dual shaft with a flat) 387 oz-in + one KL-600-
48 48V/12.5A 115V /230Vpower supply): $574.95

then I have to buy this also

G540 4 Axis driver
$249


???

[brtech]

No. The G540 drives 4 axis. You need one of them. If there is one in the package, you don't need another.

You need one G540, 4 stepper motors, one power supply and 4 drive cables. Of course, you might also need things like limit/home switches and the cables for them, and possibly a relay for your spindle.

You also need a parallel port cable to connect your computer to the G540, and some wire to connect the power supply to the G540.