Need help designing a 48vdc supply

[rsr911]

I'm converting my old Boss 5 over to more modern controls. I need some help in designing a power supply for 48VDC 40amp output from 220VAC single phase input. I was told it should be toroidal whatever that means.

[Al_The_Man]

It does not have to be Toroidal type but they are a recommended choice simply because they are much more efficient than a square laminate type transformer. The Toroidal transformer is wound on doughnut shaped steel core this ensures the magnetic field is contained within the windings and does not radiate wasted magnetic energy and therefore does not need shielding etc. Also the turns per volt is usually less lowering the internal resistance of the transformer. There are many previous posts in this zone on designing a PS.
Al

[rsr911]

I've searched a bunch of the old posts but I'm still lost. I did find one with a 1.9kva toroid and replied to it. My problem is I have no idea how to size the other parts I'll need. I've been searching the web for schematics as well but haven't found anything yet, maybe I'm using the wrong search terms? After reading those other threads it appears 40amps is probably overkill. I figuring somewhere between 1500-2000W.

[MikeAber]

This information should help.http://www.tormach.com/motion_products.htm

They have toroidal transformers and application sheets for 20 and 35 amp power supplies and components to build them.

I have done business with these people, they are honest and reliable.

[Mariss Freimanis]

They also sell a pirated G201 and said "tough toenails" when told that.

Mariss

[HomeCNC]

Try this place for a toroid. http://www.avellindberg.com/transfor...ange_specs.htm

[rsr911]

Well here is where I'm at.

1.5-2.0KVa toroid putting out 34-36VAC
4 70V 15,000uF capacitors in parallel for a total of 60,000
35A bridge rectifier.

I've heard of using a zener diode to clamp the voltage at a certain max but I'm uncertain how to do this. I'd like to clamp it at 55VDC. Also if I can't find a toroid big enough couldn't I use two in parallel?

[trubleshtr]

rsr911 I am looking for the identical power supply. did you by chance purchase "Ametek" motors from kevin at ebay?

[rsr911]

No, I'm trying to retrofit a Series 1 Boss 5 bridgeport. I've got a unipolar controller and need to have 7-10amps per axis.

[ViperTX]

Well, I just got my toroid (output 28VAC) in, the caps are in (2 ea. 75 VDC 47000 mf) and I just ordered my 50 Amp bridge rectifier, AC input module. By next weekend I should have assembled a 40VDC, 30 Amps bulk DC supply with about 2% ripple. So, I'll let you know how close my calculations are.

Recommendation: Rather then paralleling the toroids just make 2 or 3 smaller bulk DC supplies.

[trubleshtr]

vipertx what is the calculation for vac to vdc (rectification)? I had written it down but over the months lost it in the shuffle? if I re-call there is a constant value to multiply or divide the vac with to get the vdc?
good luck with the build and deffinetly let us know how it turns out.
oh ya, did you purchase all the components from one source? if so could you tell me your source?
thanks

[trubleshtr]

I am trying to build or purchase out right a power supply with the following required

50 vdc (or 48) with 36amps max out put. and perferably a center tap with 5-36vdc.

if I find a toroidal with 36vac, I think I will get 50 vdc after rectifing, someone please correct me if I am wrong.