If you are really worried about protecting your equipment you should buy a decent Surge Protector, a not the cheapest unit around. The problem with cheap units is that they will give you a false safety sensation, while they are in fact not protecting anything at all. As we shown, really cheap units don’t even have a MOV, working just like a regular power cord extension.

From what we explained, you should choose a surge suppressor that has a least three MOV’s. How do you know it? If on the product box or specs page something like “L-N, L-G, N-G” shows up, this means that the surge suppressor has at least three MOV’s.

Then look for the unit with the lowest clamping voltage (330 V is the minimum nowadays). Clamping voltage is the voltage at which the MOV’s will start working. We want that they to start working as soon as a voltage peak occur, right?

Then we have response time, which is the delay the surge suppressor has between a peak occurring and the protection kicking in. Of course we want this number as low as possible, zero if possible.

We also have the peak surge current, which is the maximum peak current the MOV’s can handle without burning. The higher, the better.

And finally, we have the energy absorption level, given in joules. This is how much peak energy the unit can handle before burning its MOV’s. The higher, the better: the probability of your surge suppressor being burned by a voltage peak will be smaller.

We also recommend extra features like phone line protection and cable/satellite protection and a LED indicating if the ground and/or MOV’s are working properly.

Of course there are much more we could say about surge suppressors, we wanted to keep it simple.

If you want to test your knowledge on surge suppressors, we recommend you to take our Surge Suppressors Quiz. This is a terrific way to evaluate what you have just learned by reading this tutorial.