Did you know it's illegal to do any 240 Volt wiring work on your caravan or motorhome in New Zealand.
On the other hand any one can work on 12 volts and that's the problem.
Just as many fires are caused by incorrectly installed 12 Volt wiring as anything else and still people think " its safe its only 12 Volts" NOT TRUE.
An electrical warrant of fitness issued by an electrical inspector only covers 240 Volt wire not the 12 volt system. 12 Volts can kill if not installed correctly.
LEGAL 16amp to 10 amp stepdown.
This is the only way to connect a camper or caravan to a house supply unless you plug into a certified external 10 amp plug attached to your house. Most wall plugs in NZ are 16 amp. Your main power cable must be at least 10 Mt long. You must have an Electrical Warrant Of Fitness ( E.W.O.F) every 4 years to plug into a house or camping ground. Any other method could void your insurance.
You must have an uptodate sticker.