and the thread title is

A simple high quality 12Volt 100Amp Power Supply- Part1

My guess is that 95% plus of those use personal computer or server supplies do so to save money.



Charles

And the other 5% of us just like the satisfaction of re-using good technology that is otherwise chucked out, and figuring out how to save everybody some money at the same time.

To be perfectly honest, a good PS is such a long term investment that personally I wouldn't resent spending several $100 on it - but where's the fun in that? These converted server supplies ARE the best you can buy - they were just built for another purpose.

Originally Posted by everydayflyer

and the thread title is

My guess is that 95% plus of those use personal computer or server supplies do so to save money.


Charles

To be perfectly honest, a good PS is such a long term investment that personally I wouldn't resent spending several $100 on it -

Problem is that one can not purchase a purpose built quality 50A 24V power supply for $100 or even $200 for that matter. Price some Meanwells or Mastech bench power supplies. On top of that it has recently came to light that these are not as clean / stable power out put wise as the server power supplies are.Well at least not when used with a specific charger.

Durability. I have had 3 nominal 12V 15A switcher power supplies to die on me over the years they all cost more and they all saw less usage than any of my server power supplies have. I have tried to kill my server power supplies but their built in safety devices are just to good. I am fairly sure that some do fail in service but it must be a very samll percentage.

If it were not for us tinkers RC would not be nearly as much fun and there would have been a lot less advancements made.

Charles

I have another question. which one is the most compact server PS that successfully converted.

Originally Posted by die4good

I have another question. which one is the most compact server PS that successfully converted.

That is likely some of the power supplies that FeatherMerchant converts for battery charging purposes. http://www.rcgroups.com/forums/member.php?u=19395

That's a slightly ambiguous question. PS supplies are like girls - they come in different configurations and everybody may have there own preference. Do you like them long and thin or short and compact?

In terms of brute Watts/cubic inch I suspect the original on this thread I started with is hard to beat. It puts out a lot of power for a very small box, the 2x12=24V version is even scarier. I personally use an old Cisco Router PS on the bench which is long and thin and fits better (as well as being lots quieter) because it supplies all the current I need most of the time.

I've seen two long thin ones put two together for 24V and put in a field box with chargers etc on top - nicely compact overall..

John

Originally Posted by die4good

I have another question. which one is the most compact server PS that successfully converted.

The 12v 47amp one shown in the link is a HP DPS-600PB measuring 55x78x280mms+handle. I just converted one using the instructions from this site as far as which pins to short out to get it to power up. They are diagonally arranged so I used 3 0.1ins pitch connectors that I bought some time ago for servo's. These are dirt cheap and the wires have to be soldered on which works out ok in practice. The connections are ground,ps kill and ps enable. I suspect the enable is the shorter pin on the central matrix of pins.

It powers up well running a few tenths of a volt over spec with no load. The fan is a little on the noisy side. Going on amateur radio posts there is a slight chance that it may slow down when a load is applied. Some supplies those guys use have no fan but they advise fitting one if the supply is to be used without a load.

One thing I'm hoping some one can tell me is what these supplies do if overloaded? Some supplies will just dump max current into the load others will fold back to a much lower current and remain like that till something is done about it. Some need disconnecting from the mains to reset them. Any one have any experience? I mainly want to run a motor with mine and it may just happen to get over loaded. ;-) Hope they don't blow up.

John

Server power supplies I have used / tested are the IBM 235 and hp ESP114 and if overloaded,shorted ,etc. they just shut down and have to be powered down for around 30 seconds then powered back up. I have read the same thing happens with several other server types.

Charles

I second Charle's advice for the ones I have played with. Given they are 24x7 supplies, it would make sense that if a fault was detected they would shut down (and the "Error" light comes on or blinks). They are probably smart enough to phone home to HP and get a replacement ordered and bill you automatically for all I know.

Also, if you start them under too high a load (such as cold light globes) they just won't power up.

John

Originally Posted by everydayflyer

Server power supplies I have used / tested are the IBM 235 and hp ESP114 and if overloaded,shorted ,etc. they just shut down and have to be powered down for around 30 seconds then powered back up. I have read the same thing happens with several other server types.

Charles

Thanks. That sounds great and all for 99 uk pence new.

I have a lathe and sometimes want to drill cross holes or mill the sides of turned parts and hope to adapt a 800kv 60 amp brushless motor and speed controller to the task. I've no idea what the motor will take at 12v hence the worry. I might also try to use it as a tool post grinder. With luck if it all overloads I will just have to turn it all off and back on again. The 47a rating of the supply might even save the speed controller.

John

John, the old "rule of thumb" suggests it will be fine. A big 1/2" 12V cordless drill would probably drill the holes and do the milling you want easily so the mechanical energy required is well within the capacity of a 12V, 25A device.

For example the "Dewalt DC940KA Heavy Duty XRP 12V Cordless Drill/Driver Specifications: Voltage 12 V Max Power 290 W"

John

Originally Posted by Ajohnw

Thanks. That sounds great and all for 99 uk pence new.

I have a lathe and sometimes want to drill cross holes or mill the sides of turned parts and hope to adapt a 800kv 60 amp brushless motor and speed controller to the task. I've no idea what the motor will take at 12v hence the worry. I might also try to use it as a tool post grinder. With luck if it all overloads I will just have to turn it all off and back on again. The 47a rating of the supply might even save the speed controller.

John

I have just bought and converted an HP Power Supply DPS-600PB and it works fine. As it is difficult/impossible/expensive to obtain the mating rear connector, I have soldered a couple of 4mm test sockets between the blades of the existing connector which makes a convenient termination.
The extra low Z capacitor is only to reduce pk - pk ripple to about 60mV at full load and not strictly necessary.
BTW I think the only real ground pin is pin 8 which pins 6 and 10 should be commoned to in order to enable the main 12V output. Full Load regulation is only 0.11V and the overload characteristic is trip off at about 56A, break input to reset.
So as I paid £9.50, I now have a good 12V, 50A psu for just over a tenner!, ($16)

Wayne

Nice one. Hard to argue value for money!

Thanks, Wayne. I have put a link to this on the summary page that starts here.

http://www.rcgroups.com/forums/showp...18&postcount=1

for folks who are converting this supply.

Can you post a picture of the PS label just to make it easy to positively identify it? There's at least two (quite different) HP "600" PS that I know of.

John

Here is the label identifying the PSU type modified in Post 312.

Wayne

PS Although it's HP, I note it's made in China - will it be reliable!! I remember buying a HP 4digit DVM in 1969 for £450, that's £5178 in todays' prices, over $8000! - how things change! - that wasn't made in China.