So I have a 12 volt battery pack that comes from a TETRIX robotics kit and the wires that come off of it are very thick. Too thick in fact because they won't fit into the DC power ports on the Adafruit motorshield. Is there any way for me to downsize the wires so that they would fit?
Solder on thinner pieces of wire.
So the battery will be just as effective if I solder on the smaller wire?
Yes, the end device just won't be able to draw quite as much current. With the end device having a smaller contact size, it would appear to not need quite as much as the battery is capable of anyway.
Thicker wires have lower resistance and are often used when electricty needs to travel a distance. Using a very short piece of slightly thinner wire will have very little impact on the total resistance.
If you look up the resistivity of copper and measure the wire you can calculate the resistances.
...R
Is there a certain point at which the smaller piece of wires diameter would be to much smaller?
In simple terms, that point is reached when the wire melts (ie fuses)
As you reduce the wire cross-sectional area you increase its resistance and as the resistance increases, so does the voltage drop across the wire (assuming constant current). Since wattage developed across the wire is a function of v2 you eventually get to a situation where the heat generated exceeds the ability of the wire to dissipate it.
However, unless you are demanding substantial power (several 10s of amps)., even a fairly thin wire may suffice. Feel the wire when under load to see if it is hot; if so then you need to increase its diameter
Ok, thanks that makes things very simple 