Using 2 power supplys charging 1 battery

[kidthorazine]

I have one of those emergency jump start units that I need to recharge quickly. Can I use 1 14v 850mA dc wallwort and 1 12v 1000mA dc wallwort with the positive outputs connected together and the negative outputs connected together to charge the 12v dc battery inside the unit?

 

[duke37]

I wouldn't, if it is a lead acid battery you will need 14V and the 12V supply will not be of much use if it is in fact 12V.

If the supplies are different one may be doing all the work. I would even be hesitant about using two similar ones.

 

[BobK]

You should never connect two voltage sources together. All they will do is fight each other.

Bob

 

[gorgon]

No you can't.
In addition to what's said, if the 12V Power has no protection against backfeeding, you may get some magic smoke from that one.

To parallel power supplies, always use the SAME output voltage, AND use a diode from each power's V+ to the common V+ point. For charging purposes, you then need to be able to adjust the voltages to compensate for the drop over the diode(s).

In short, this is a BAD idea, if you don't know what you are doing.