Belkin surge protector - repairs

[immortality]

Hi All,

I have a couple of Belkin surge protectors around the house, I noticed recently that the one in the lounge for the TV/entertainment unit no longer has the green "protected" light on.

I'm just wondering if anybody has ever pulled one apart and repaired it?

I'm thinking it's just simply a couple of sacrificial components on a PCB board that will need replacement?

Thanks in advance.

[immortality]

Well I pulled it apart. Haven't found anything wrong with it as yet. All the components seem to test ok.

The bloody thing isn't worth what they charge for em at the shops though ( I think it has maybe $15 worth of components in there), good thing the missus generally gets em thrown in for free when we purchase large items.

It has 2 sets of capacitors (looks like some sort of power smoothing), each set has it's own thermal fuse, all test OK as far as I can see.

[The1]

if it's got anything half decent in it it'l probably have some MOV's on the mains and Gas Arrestors on the phone/network plugs, they all vary with voltage usually fair high as they want them last instead of breaking within the warranty period, no good for small surges to protect equipment, ive had a few mates that had things on the belkin devices and have gotten surges through and blown up. They had the deal where it covers what's connected upto a certain amount, mates TV blew up with the board, rang the hotline and got the TV and Board replaced no questions asked lol.

[immortality]

The phone connectors just look to have 4 fuses (2 are covered with heat shrink) and 4 transistors (one for each of the four pins). It's a completely separate board.

Nothing plugged into the board has failed so if it has had a surge it seems to have done it's job.

There is one component I haven't seen before but the continuity tests OK

Edit, the un-identified component seems to be a suppression capacitor? So I guess it having continuity isn't a good thing. Need to do a little more research.

[The1]

they look like a capacitor but are MOV's, usually across the mains, they help filter voltage spikes back to earth, they wont help with continuous over voltage though, eventually they fail, most powerboards have it factored in so they will last the warranty period at least.

http://en.wikipedia.org/wiki/Varistor

[Holden202T]

most powerboards have it factored in so they will last the warranty period at least.

yeah usually a week after warranty expires I've found with anything!

[immortality]

So what would you expect to see when you test a MOV?

It does indeed look correct as it does include a thermal fuse with each cluster but it all seems OK. Both thermal fuses are good.

No signs of heat or burning anywhere either.

[The1]

from the wiki link above, Read the middle paragraph in "Background" section

A varistor remains non-conductive as a shunt-mode device during normal operation when the voltage across it remains well below its "clamping voltage"

So using a multimeter testing the device by itself should read no resistance in ohms mode. If it's short or looks damaged from overvoltage then it's no good. I would htink to test it further from there it would need to have a voltage run through it gradually upto it's rated voltage to where the point it starts to open, which will show how degraded it might be.