12S socket wiring gauge

[joebloggs2022]

Hello all

It is striking how the wiring gauge (and hence current carrying capacity) of standard 12S socket wiring is much lower than would typically be used for, say, connecting a secondary battery on-board the vehicle in a camper van. What is the reason for this? Is the assumption that a Leisure Battery on-board a caravan will rarely discharge enough to give rise to large enough current spikes to exceed the capacity of the lower gauge wire (and when it does, the fuse will blow)?. Is there a reliance on the fact that the voltage drop over the long cable runs will act to limit the maximum current that can be drawn?

Many thanks in advance
Joe

 

[UNG]

A 12S socket is only carrying a charging current to the caravans charge controller the leads to the caravan leisure battery from this have a larger CSA. A camper van setup properly will usually have a similar charge controller although some just use a split charge setup. Generally when running the largest load on the 12S socket is the fridge

 

[joebloggs2022]

Ah - that makes sense, thanks! So I assume that the caravan's charge controller limits the current that is drawn from the vehicle through the 12S socket?

Are all caravans fitted with charge controllers?

Joe

 

[UNG]

Are all caravans fitted with charge controllers?

For at least the last 20 - 25 years most if not all British built caravans have been fitted with them don't know about the European built caravans