Cheap 24v SMPS - advice needed

[ericallan]

Nuuk may be able to help here - I've found some 24v positive SMPSs for about £10 each. May be able to get some more if there's any interest. I've tested the output earth and can see no connection between it and the mains earth or chassis. Are there any other tests I might try before tying two together to make a split psu : 24/0/-24 ?
They are Power-One MAP55-1024 @ 2.5A.

 

[ericallan]

Update

- Power-One have very kindly replied to an email and said that the output earth is floating.
Anyone want some?

 

[Leolabs]

Cant do much with only 2.5A

 

[Nuuk]

Cant do much with only 2.5A

Sort of agree although I have run a GC (both channels) off one of the 8080 modules (+12 volts/6A and -12 volts/1A). But you will need efficient speakers!

 

[ericallan]

Wouldnt I have a total of 5 amps with 2 supplies in parallel?

 

[Nuuk]

Wouldnt I have a total of 5 amps with 2 supplies in parallel?

I believe so! I have not run mine in parallel though!

 

[jackinnj]

Power-One had the misfortune of orienting a large part of their business towards Cisco in the late days of the internet bubble. As a result their stuff remains comparatively cheap. They make very good supplies.

 

[wes-ninja250]

Don't forget, you can't just run any two arbitrary SMPS in parallel. FWII, there are usually synchronization issues.

Wes

 

[sagarverma]

don parallel two psu,there are compatibility issues that need to be addressed.
during low of one there can be high of other frying up whole of the system.so don,t do it in any case.serious warning

 

[ericallan]

don parallel two psu,there are compatibility issues that need to be addressed.
during low of one there can be high of other frying up whole of the system.so don,t do it in any case.serious warning

Thanks for that - I'll give them a go in series anyway, just for the hell of it.

 

[sagarverma]

ok!do what u wanna.
but lemme tell ya that psu are not like batteries,to be paralled or joined in series.
so be careful!
wear adequate protection and do post the results for all others to benifit from your daring experiment

 

[Chris Owen]

If the outputs are isolated from earth ground, then there is no problem with putting them in SERIES to make a bipolar supply.

I agree that putting them in parallel could be a problem.