We're off to France this year and want to know about polarity testing. Apparently some sites are the same as UK bot others are different. How do you find out without blowing something up?
The easy way is visit your local caravan accessory shop and buy a plug in tester,they are not expensive,they plug into the normal three pin socket and the lights displayed tell you what if anything is incorrect.
Also buy the bits to make up a reverser lead to fit on the mains lead to correct any reversed polarity.
You won't blow anything up if the polarity is wrong but your safety will be at stake in case you touch a wire or connection that is not or inadequately insulated.