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HELP - 9V+3V=12V? Power cord

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Oct 7, 2007
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running a 12v fan on 9v

got a camera i want to test and it requires 12V. Can i get a 9V charger and 3V charger snip off the ends and SAFELY use the 2 chargers to make 12V. Or will it short and and go very black through out the house.

Added after 16 minutes:

Or can I get 12V out of a USB cable?

using 12v to power 9v

Charger ≠ Power Supply ..

Assuming that you have power supplies (not chargers) you can try to run 12V-rated camera of 9V power supply without messing around with two power supplies ..
Most of these cams will work with voltages between 9V and 15V ..

Again, if these two are power supplies (rated for similar currents >> than camera), you can connect outputs in series .. 9+3=12 ..

USB offers only 5V !!!


how to check power on 9v cord

If these are chargers to charge batteries etc: DO NOT!

using a 9v cord on 12v

i have tried the 9V plug but the picture is b&w and disttorted... i put this down to not enough juice.
Thus i got 2 power cords that plug into a)cb radio charger [9V] and b) mobile phone [3.7V]

These cord plug into mains power socket of a house...
So just twist the ends together and i have 12.7V?

Battery chargers are not like batteries or bench power supplies. You can't think of them that way.

Even if you could think of them as batteries, twisting the leads together puts them in parallel (at least the way I think you're thinking of it :)), not series, which would probably still give you around 9 volts.

But as I said, they're charging circuits and loading one with the other is not likely to have a good outcome.

Get the proper charger/PS for your camera.

This depend on the power.
Note if the 2 chargers supports the current required to charge the battery so you can use the chargers to obtain safely the 12 V.

I disagree with you. Chargers are there in very different configurations. NiCd, Lion, Lead acid. All wiht a different charge characteristic. Do you know what happenens if you put these types in series?

So don't do this with chargers unless you know the exact characteristics of them.

I have a 12v computer fan i want to run 24/7
if i hook it up to a 9.6v rc car, batterie charger...
will this cause a problem

Johnnyy said:
I have a 12v computer fan i want to run 24/7
if i hook it up to a 9.6v rc car, batterie charger...
will this cause a problem

Battery chargers are designed to supply a current to a battery. They are not a voltage source, and should not be used as one.

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