I think the safest way is any method that is completely "contact-less" I thought about offering some advice on a shunt-based schema before, but have since decided not to. Too dangerous. Out of interest -- it's completely illegal in Australia now for unqualified people to mess around with 240VAC. It's the way it should be too. If you're on here asking questions about 240 then I'm sorry to say that you don't know what you're doing. There's no second chances with electricity.

Trent Jackson