Thu Dec 10, 2015 6:11 pm by AZD
Yes, it should be as simple as swapping the lamp for a new one. They have the same physical dimensions whether rated at 6V or 12V. The old wiring is fine assuming it is in good condition to start with. For a given wattage, a 12V lamp will use half the current of a 6v lamp.
Just for fun, these are the most basic and useful equations in all of electrical engineering:
- Ohm's Law: V=I*R, where V is volts, I is current (amps) and R is resistance (ohms).
- The Power Law: P=I*V, where P is power (watts), I is current (amps) and V is volts
The second is based on the first, and there are other ways to express them by re-arranging the terms. The most useful of these is P=I*I*R, and this describes what happens to the power dissipated by the wire itself.
The wire has some natural amount of resistance, which is why wire gets hot if too much current is run through it. But the interesting thing is that it dissipates power (heat) exponentially as the current is increased. The opposite is also true. When the current is reduced, the power dissipated by the wire drops exponentially. This is true even when the total power delivered to the load (like the lamp, for instance) remains the same. This means that 12V systems can use thinner wire than 6V systems, all else being equal. Or, in your case, the 12V lamp will be perfectly happy using the wire that was already used for the 6V system.