smps modification 24v to 12v possible???

[Rogelio]

I have several 10amp 24vdc Sola power supplies.  I dont use any 24v items.  Does anyone know if I will encounter problems with just replacing the voltage adjust resistors to lower output to 12 volt?  There is a 16v zener but I believe it is only for the 24-28v led.
Roy

[JonB256]

If you have the Sola model number, I'd search the internet for "Changing Sola power supply from 24v to 12v"

at a minimum, post the model number here. without that, we're just guessing. even with the model number, we may be guessing, but it would be a smarter guess.

[Rogelio]

actually they are 20 amp.  SDN 20 24 100C.
I already searched before I posted.  plenty of repair sites but couldn't find a modify site.
the board has empty smd resistor pads parallel to the existing voltage divider resistors.
Adding one lowers the voltage to 12v but I was wondering if it may damage the supply since it was designed for a different voltage.  there is a 110/220 select switch that also affects the resistor network, so I think I should be good.

[vairmoose]

Picture of board?

Larry

[combustionmark]

Also overvoltage and undervoltage protection circuits have to be adjusted, or they will just shut down.
There will be intermittent pulses that may cause problems.

Save them for 24V MR16 use.

Have Fun

[Rogelio]

Correction.  the switch is for parallel use.  input is 115/230, either one.  no switch needed since it is smps. 
I have already closed unit up, so a picture will not be easy. 
I went ahead and soldered a 22k resistor which bought voltage down to an adjustable range of 11 to 14.5 vdc.
also replaced 16 volt zener with a 10 volt so OK light is lit.
I will try it and see what happens.

[chrisatpsu]

just get some 24v items  : )

[Rogelio]

Or... some 12 volt power supplies! 
Being a DIY site, I am trying to use what I have.  Something I do not have a use for. 
If it works....fine.  If not, just unsolder 1 resistor and replace a zener and its back to an unused 24v supply.
Worst case I throw it away if I destroy it.
Roy

[wwwgator]

we use the same PS all over our plant. I took one apart on my bench and there are more than resistors that need to be changed.  There is a voltage regulator on the bottom board attached to the heat sink (near the label D11) as well as the monitor board( entire upper board) ......sum it up to say they are not easily converted.....

[Rogelio]

thanks