Surge Protector

Does anyone here know how surge protectors work? Woke up yesterday to no phones, internet or tv. Had a storm over night. Telephone repair man found a DSL filter blown apart. Phone line running the internet goes through a surge protector. We had to bypass the surge protector to regain phone and internet connection. Indicater light on the surge protector still shows protection working. AC power outlets on surge protecting are still working but tv that was pluged in to it will not turn on. We found a blown fuse in the tv. This does not make sense to me. Can anyone explain this? Surge protector obviously did not protect and indicator light is not correct.

Most of 'em (the little strip kind, anyway) do their job by committing suicide.

If it has ever blown before, they can be reset to give power, but the surge protection feature is gone. That's why the darned things should be replaced after they once trip.

Allan

A lightning strike can destroy the best surge protector.Heres how surge protector works in a fence charger.A device called an MOV Is rated at 130 volts.If the voltage goes over 130 the mov short circuits and blows the chargers fuses.Many times the mov is destroyed and the charger has no damage.A surge protector on our phone protected the computer but I had to do repairs on the surge protector.I have seen fence chargers blow to small pieces by a strong lightning strikes.

I no longer trust any of them. About 3-4 years ago, we had a lot of computer and router parts hooked into a surge protector with a $60,000 guarantee on it. In other words, the strip manufacturer would pay out up to $60,000 if the surge went through their strip and destroyed electrical devices that had been plugged into it. We had lightning hit our house one night and just about everything appliance in our house THAT WAS PLUGGED INTO AN ELECTRICAL OUTLET failed, including all of our equipment on the electrical surge protector. Everything in our house that was NOT plugged in was fine. So we sent the electrical surge protector back to the factory for them to "inspect" it and they told us that it was fine and had no problems. When I talked to them on the phone about it and said that the surge went through their protector, they just told me that sometimes it's the static electricity in the air that kills the appliances and electrical devices, not necessarily the surge itself.
Hmmmmm.....funny how all the appliances that were not plugged into an electrical outlet survived. We had no recourse and had to pay for all repairs out of pocket.

They are zener diodes which are "open" up to a set voltage then conduct above the set voltage.
Be glad the surge unit was there.
Diodes and semi conductors are not made of 4/000 copper conductor. Exceed the rated voltage, current, pressure, force, temperature of anything and it's going to fail.
As for those who can't understand everything failing after receiving a DIRECT lightening strike? Do you have any clue of the peak DC pulse in current and volts in a lightning stroke?
What do you expect for something purchased at Walmart?

Surge protectors are like a hanky over your mouth in a dusty environment. They will clean off static charge pulses into the thousands of volts, but of no consequential duration. They do this (cheaply) with a choke (coil of wire tuned to non 60 cycle higher frequencies, and capacitors that can suck up voltage temporarily, then feed it to a resistor. THey are only good for casual static buildup from shoes on wool carpet and nylon jackets on wool sweater type issues.
UPS (uninteruptable Power Supplies) are a step up in the sense that they consist of a 1:1 isolation transformer that separates the power out from the power in. The power is then rectified and filtered to DC charging a storage device (usually a battery) the battery output is then inverted into regulated AC for use by the device plugged into it. They are much less prone to passing destructive spikes, and will work even with 30 volts on the input at wild frequency variation.
The more over 250$ you spend the better these perform. Some cost thousands and can handle a room full of equipment. They are also capable of running the equipment for a set time while it shuts down (usually because the equipment is digitally interlinked (smart) so it shuts down when the power is interrupted. Though better, these are not lightning protection.
Remote disconnected backups are your only protection. USB HDD with an unplugged status works well One terabyte for about 100 bucks at sams club. The best policy is unplugging and moving all wires 12 inches from the outlets and cable jacks/modems, A pain, but what is the value of the content you have on the equipment.
Jim

Tom surge protectors do not protect you from lighting stricks. They are designed to stop the power surges . Like when power goes out and comes back on there is a surge at first and these protectors help to prevent damage.

Gamblles the surge protectors are not desigened to stop lighting stricks. I have been hit twice over the last 30 years and my insurance company picked up all the damages.

To understand what a protector does, well, first let's review what a lightning rod does.

Lightning seeks earth ground. So a cloud connected to earth via a church steeple. A wooden steeple struck because wood is an electrical conductor.

But wood is not an ideal conductor. The 20,000 amp lightning current through wood (a poor conductor) creates a high voltage. 20,000 amps times the high voltage means high energy dissipates in the wood. The church is destroyed.

Franklin put a lightning rod on the church. Does a lightning rod do protection? Of course not. The lightning rod is only part of a connection to earth that does not go through wood. That 20,000 amps down a wire to the earth ground rod creates a near zero voltage. 20,000 amps times a near zero voltage is near zero energy. No damage.

Nothing stops or blocks a surge. Any protector that claims to perform that myth is quickly destroyed. Then the naive recommend that useless protector.

The effective protector does what Franklin"s lightning rod did. Connect lightning harmlessly to earth. So that nobody even knew a surge existed.

A lightning rod is part of a system that protects the ‘building’. Lightning striking AC wires down the street is a direct lightning strike to every household appliance. Earth one "whole house" protector as part of a system that protects ‘appliances’. In both cases, protection is provided by what harmlessly absorbs hundreds of thousands of joules.

So what does a protector do? Two completely different devices are both called protectors. One adjacent to an appliance must somehow stop, block, or absorb the surge. Another and well proven device (also called a protector) connects to earth BEFORE lightning enters a building – like Franklin’s lightning rod.

Which solution has been used for over 100 years to have no damage from lightning? The properly earthed "whole house" protector. Facilities that cannot have damage always install the ‘whole house’ type protector. Why does lighting strike munitions dumps and not cause explosions? ‘Whole house’ protectors are that well proven.

Some protectors are so grossly undersized as to fail. So that naive consumers will make assumptions only from observation rather than first learn well proven science. Informed consumers earth only one "whole house" protector so that direct lightning strikes cause no damage - even to the protector.

A direct lightning strike is typically 20,000 amps. So the minimal "whole house" protector starts at 50,000 amps. These are sold even in Lowes and Home Depot for less than $50.

But again, that is only a protector. Also upgrade your earthing to both meet and exceed National Electrical Code requirements. Because earthing (not a protector) does the protection. As Ben Franklin demonstated even back in 1752.