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i mean how could there be a overload or a short, my battery always provides 12v(roughly)?

Quotei mean how could there be a overload or a short, my battery always provides 12v(roughly)?Murphy's law!There are just too many ways to create a short or overload. Here's a few I've experienced:Motor windings overheat and short together.A component fails and shorts internally, caps, ICs.A cap or IC is wired or inserted backwards.Two wires get pinched together, cutting through the insulation and shorting.Slipping with a screwdriver or other tool and shorting two contacts.Connecting the wrong wires together.Miscalculating a resistor value or misreading a resistor value that draws way too much current when the circuit is turned on.Yes the battery will try to provide 12V but at what current? What happens when the load becomes close to zero Ohms? Hint: use Ohm's Law to calculate I. Then what happens at the battery?

OK so : 12 / .... I'm not sure of the resistance, how do i calculate that? ..... = I

QuoteOK so : 12 / .... I'm not sure of the resistance, how do i calculate that? ..... = IOHM's LAW, google it.Anyway, if you tried to calculate the current you would find that with a resistance close to zero (say 0.01 Ohm) the current draw from the battery would go close to infinity (ok, only 1200Amps). This would severely overheat the battery and it could rupture and maybe even catch fire. That is if the wire didn't catch fire and burn off first.Did you look at the wire table I posted the link to?Will 18ga wire carry 5-6 amps?

Questions are good. I just try to get you to figured out the answers.Look at the wire chart again. Power transmission means a very, very long piece of wire so it is the resistance and voltage drop that limits the recommended current to 2.3A.Look at the column to the left titled "Maximum amps for chassis wiring". This is for shorter wires like on your bot. What is the max current under this condition?