I have a device which takes 4xD batteries which I would like to instead hook up to a spare wall charger. I have looked at the voltage of the batteries and it seems most batteries are 1.5V. My device has 4 of them (seemingly in series – but with 2 down one side and 2 down the next. Ie:
simulate this circuit – Schematic created using CircuitLab
There is 1 wire (black) connected to the negative terminal on the top. A Red wire connected to the positive terminal on the top, and then an orange wire connected to the negative terminal at the bottom (although this terminal is just a plate of metal so I guess it's neither positive nor negative as they are both connected? Whereas the positive and negative at the top are separated.)
My wiring diagram seems to indicate this orange wire is ground (I guess that makes sense if both positive and negative terminals are connected then the voltage on this plate is 0 correct?
If that is the case – then am I correct in thinking 4 batteries in series this way can be substituted for a 6V dc charger? (the wiring diagram shows the terminals as -3V and 3V). Also if I substitute the batteries for a dc charger, how do I connect ground?
Best Answer
Unfortunately, just a 6 V supply won't do it. You really need a ±3 V supply. Or, you can get two 3 V supplies and connect the + of one to the - of the other. That common connection will be the ground of your circuit. The remaining + and - ends are the +3 V and -3 V ends.
The latter is probably easier to source. Basically, get two cheap 3 V wall warts.