• Firstly, get the basic facts lined up.
• Secondly, decide what level of protection you need.
• Thirdly, make sure the technical terms don't confuse you.
• Finally, get to know which type does what.

Thirdly, make sure the technical terms don't confuse you.

Like other advanced technologies voltage control tends to talk its own language. So it is important to know what the basic terms mean and especially when comparing equipment from different suppliers, to be sure that everyone is using the same definitions and applying the same performance parameters.