[Docop]

Hi

I'm looking to confirm if the power supply I choose will be ok or be too narrow to survive a 4th axis build.

I intend to build a rack and pignon with 2x 500oz Nema23 on Y and 1x on the X. All those running direct drive with 17teeth pinon, no gear reduction.
Nema spec as : 570oz 3v 5a 2.5mH calculated voltage 15x= 45 20x= 60.

I will use a 48V switchingpower supply. I see I need to plan for a bit of overhead to not fried it. Is using a value of 0.7 for the efficacy will be ok or too high for the nema amp?

As 5amp giving me = 3.5amp * 3 motor running at same time = 10.5amp
The Z should be active just alone, but on the 4th axis, the motor will spin too, at same time of 3 other.I will end up with a 14amp then.

Is a 800w 17amp switching pwr will be ok, for a 4 axis or better to go over a 20amp ?

Without going to the linear power supply route..

Thanks very appreciated, i'm quite stall over the amp rating for quite a while.

[ger21]

What type of machine is this, and what drives do you plan on using?

Generally, a motor will not draw more than 2/3 of it's rated current, so a power supply with 70% of the total added ratings should be sufficient?

What's wrong with a linear supply? They're not expensive, are more readily available in higher current ratings, and are very simple.

Now, depending on the type of machine, direct drive rack and pinion may be a very poor choice.

[Docop]

Hi

Yeah, a linear is simple, but quite a bit heavier too. And on the energy efficacity, the switched power I see will be about 86% efficient. So I prefer those a bit.. On the
price it's a bit lower around 30$. I will run on 240v, and the switched one will took about 7amp. I think the linear one could be higher.. isn't it ?

On the system, I'm inspired over RAWcnc, the rack with being supported on each end will give a pressure over the pinon under it and create a good contact.

I do see a setup as direct drive that look to work good. But, is the only difference with a gear belt setup is that you can used a more wider range of stepper with higher inductance, because of using a gear reduction.. ?
From what I see the precision could be the same. Of course, perhaps a bit more of backlash..

Thanks again.