Quote Originally Posted by Al_The_Man View Post
That appears to a MOV, Metal Oxide Varistor and is used for absorbing overvoltage or voltage spikes, the problem with them is if the absorb more energy than they are designed for they self destruct.
Hopefully there will be a number on it, otherwise you have to go by the normal or peak operating voltage across it, and the physical size for the energy value.
Al.
Unfortunately, it has no number on it. The voltage is 240V. I have o look for the manual. This is a chinese vfd so manual does not make sense some times.