If a 24V system is better than a 12V, please school me with some learnin for my edumacation knowledge.
The operative word here is "better"; better than what? Depending on your position and perspective, better may be worse to others. But here goes:
Electrical systems have two things to deal with: voltage and current. As one or the other increases (typically both) you can get or transfer more power. So usually "better" means "more power".
For voltage, even common place insulators are good for many tens of volts; they typical cheap insulated stranded wire that is used in most automotive wiring harnesses are often rated at 300 volts maximum stress (yes, there are wires that are rated for only 20-30V dc applications, but even though they are rated that low they can really hold off hundreds of volts). So the difference between 12 volts and 24 volts is pretty inconsequential as far as insulation is concerned, and neither are a safety issue. Using 24V over 12V (all else being equal) means you can double the power that is piped around the truck. From this perspective, 24V is "better".
When current flows through a wire it creates heat. A larger wire (bigger cross sectional area) means less heat will be created. Wire area is measured and defined by AWG (American Wire Gauge) standards where a decrease of three gauges is almost a perfect doubling of the wire area (from #22 gauge to #19 gauge, for example). Decreasing another three gauges doubles the area again, so #16 wire has four times (4X) the area of #22. For the same amount of heat lost within the wire, #16 can carry four times the Amps that a #22 wire can carry. The amount of heat that can be allowed is defined by the type of wire insulation (how easily does it melt or burn?) and how many wires are bundled together (sandwiching something hot with other hot things makes the first even hotter). In house wiring, #12 gauge is allowed to safely carry about 20 amps maximum. Knowing that three gauge numbers doubles or halves the wire area, you can see that #15 wire could carry 10 amps, #18 can carry 5 amps, #9 can carry 40 amps, etc. and these are not "hard" current limits, but are a good rule of thumb.
Power (measured in watts) is voltage times current. So for the same power, if we double the voltage (from 12V to 24V) we only have to carry half the current. The wires can have half the area, take up less space, have less weight, and be more flexible. Connectors in the wiring harness carry less current. Less current is less heat, less chance of melting insulation, less chance of damage. Two batteries in series to create 24V only need to supply half the current for the same power; the batteries are not drained as fast.
So to convert a Pinz to 12V and keep all the lights, starter, ignition, accessories, blower, all that stuff at the same power level, every wire would be best replaced with a larger, thicker wire; the connections would need to be rated for the higher currents, and generally would have more wasted power (via heat) within the wiring harness unless the wires are made even larger. There is nothing wrong with doing this, but have you really gotten a big benefit from the effort of doing so?
So a 24V system is "better" due to less current which is easier on the wiring, connections, batteries, etc. The drawback is that there are not as many 24V devices as there are 12V parts; but most 12V "stuff" is fairly low power, anyway (heaters and winches are the exceptions) and can be easily powered if a 24V to 12V converter is used.
My opinion is that the 24V electrical system is an improvement over 12V; but I won't be trying to convert my autos to 24V, they are fine as they are at 12V. I'll shut up now.
Jim M.
712W and 710M
