Converting 110/220V supply to autovolt

[rogfanther]

Hello,

I have a DPS-250AB with burnt, charred toroid, and while it maybe can be rewound, it will take some time, and the client decided he needs the machine.
I´ve explained the situation, and they are ok with me substituting the insides of the old supply.

I´ve located some small ones, that fit inside the dead one, but the original are automatic voltage selection ones, and the ones I found have the 110/220V switch. I cannot trust nobody will use it in a 220V outlet.

So, have anybody managed to transform some of these selectable supplies in auto-selectable ,dual voltage or however it is called ? I´m ok if I have to switch the input caps, or something like that. Also , the learning experience would be good.

Thanks for the help.

[Th3_uN1Qu3]

Re: Converting 110/220V supply to autovolt

You either need an active PFC stage like the old supply had, or some type of line sensing circuitry that switches a relay. The circuitry isn't exactly trivial to make, and it's not worth the effort.

[rogfanther]

Re: Converting 110/220V supply to autovolt

Hmm, ok, thanks. I am also spending too much time trying to be creative with this psu ....

Will try to fix the toroid, and also measure if it is possible to cut a hole in the casing for the switch ... whatever can be done first...

Thanks again .

[370forlife]

Re: Converting 110/220V supply to autovolt

I actually have an old ATNG unit that does sense the voltage input and changes itself accordingly, no PFC either.