Rationale behind 24 volt systems? (1 Viewer)

[D0g]

This is my 1980 BJ41 with a 24 Volt electrical system.

I have always wondered why Toyota used 24 volts in certain markets for their diesel models . Generally 24 volt systems are used in commercial and military applications, and the reasoning behind those is because of communications equipment that required 24 volts. I don't see a reason why a civilian vehicle would need it, does anyone know what Toyota's purpose was for doing so?

 

[tlaporte]

I thought 24V tended to be standard for colder markets, like Canada and Northern Europe, while 12V were standard elsewhere. Speaking strictly based on what little I’ve observed about the 40-series markets.

 

[Freewheel]

It seems like that's the likely answer, is your BJ from Canada? Most of the Northern Diesels are 24 volts so they have more power to start up at -20.

 

[Dprio34]

I believe it is to get the same power (watts) you only need half the amps. Aircraft use 24v to reduce the size of the wires / gauge and save weight. Probably the same reason for radios to reduce bulk / size of things.

 

[D0g]

Thanks for the replies that makes sense.

 

[BreckenridgeCruiser]

24v was also NATO spec and many large industrial operations used 24v heavy machinery. Since landcruisers in many parts of the world were used for work and not play, it makes sense they would use a heavy machinery design pattern for their electrical systems.

That said, it also greatly increased the reliability of the 24v wire harnesses as all land cruisers have the same gauge wire regardless of voltage. Essentially that makes the 24v wire 2x 'larger' than 12v when it comes to current and therefore more efficient and safer.