Im trying to use a 18 v makita batt to power a rca projector the projector specs are 12 v 5 amps
I have a deca buck converter i set it to 12 volts (12.2) but I cant set the amps when I turn the set screw up in does go higher than 4. 3 amps if I turn it down it shuts off. Does it only takes the amps it needs and the 5 amp spec is the max? Also it say in the buck converter instructions that the input and output cannot share same ground what does that mean? The ground comes from the battery or power source where would I get another ground? Thank you
In a supply you cannot "set" the amperage. The amperage is determined by the load. What you can set it the MAX current the load is allowed to draw.
Also it say in the buck converter instructions that the input and output cannot share same ground
This sounds wrong. Can you tell us what buck converter you have? Perhaps a link (even if it is to an ebay item).
How is that article in any way related to the buck converter that the OP has? 
I'm 99% sure that's not true. If you bought from a "cheap supplier" the information may be wrong or wrongly translated.
It's not unusual to have an isolated ground that can be optionally connected. A battery doesn't have a ground, just + & - connections. Sometimes two batteries are used, one with the - connection grounded and the other with the + connection grounded and then you have positive & negative voltages available.
I have a little isolated DC-DC converter in an automotive application and I've grounded the + output in order to get a negative voltage.
It means what it says: don't connect the input ground to the output ground, however if that's true then one of them isn't really ground. While I share the doubts of the other posters I can see how that could be true, although I don't ever remember seeing it on a PSU.
These buck convertors often produce “-5v” relative to the input ground - so on the output side the -5v is then used as the gnd and the other terminaI is then + 5v . It’s a consequence of the design using inductors .
A lot of the battery packs , charged via USB , are like this - as I found out to my cost recently
If that makes any sense !!
This topic was automatically closed 180 days after the last reply. New replies are no longer allowed.