Originally Posted by
phil alvirez
the guys that fly r/c planes powered by electric motors have found a way to avoid sparks when connecting the battery by soldering a thin wire to each terminal and a resistor between. there is a connector that allows current to flow or stop. when disconnecting the battery you can disconnect the wire before or after, but when connecting, you do the wire before, then the main. this way there is no spark. perhaps some1 with the knowledge could calculate the size of the resistor. just an idea-that works.
Do not put a resistor in a circuit that flows 700+ amps. You are asking for a LOT of hurt, pain, and burns. R/C planes are little itty bitty devices not a huge car battery. Don't even try this (home, shop, office, abroad).
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