We have have a lot of issues with council transformers and equipment being tampered with, creating power surges in peoples home's. So we install surge arrestors.
The only ones available to us are the CBI ones, in 220v and 380v.
So the instructions are as follows, the line goes into the top, and the earth wire goes into the bottom. This earth goes directly onto the earth terminal in the DB.
Now how does this unit actually work. I assume when more that 230-240v occur, it shorts the live to earth and the main trips.
But how do we know this, So i have been getting g my customer to double their protection, by getting surge arrester plugs on their expensive appliances for that extra protection.
Can any one elaborate or give some other advice on the issue.