Quote:
Originally Posted by
valoidr 
check out Belkin, Tripplite also -IMO over a C-note is too much to pay.
This post seems to be very credible, and based on facts. It's old, but still valid:
(I couldn't figure out how to just copy a link to the post, so here's the whole thing)
Posted by Doug Deacon (7-11-03)
There are only two technologies widely available for surge/spike protection. Once you understand the differences between them, the decision about which technology to buy is trivially easy.
Metal Oxide Varistor (MOV) surge suppressors
MOV's are used in products sold by Monster, APC, Walmart, Radio Shack and nearly every other surge suppressor and UPS on the market. MOV's have three features you need to know about:
1. They all have a finite clamping speed, some of the surge gets through before the rest is shunted to ground. Your "protected" equipment takes a constant series of mini-spikes. Nothing you'll notice, nothing to invoke the $5MM equipment replacement warranty, but not good for delicate circuits either.
2. MOV's work by shunting excess voltage to ground, which contaminates the ground of all circuits that share the same ground. Electrical grunge and screwed up voltage for the whole system.
3. MOV's are all designed to fail. They are a consumable. Every spike they shunt, whether large or small, degrades them. That's what "joules ratings" are for, they indicate how many joules the MOV can shunt before failing.
Once an MOV fails, and they all will, they provide no more protection. Zero. If your unit doesn't have some kind of warning indicator (most don't, unfortunately) you'll find out when the next spike comes through and fries your equipment.
UPDATE: a few lucky users will find out immediately when their MOV takes its final hit, since they've been known to ignite. That's right, a fire in your HT rack! To be honest, this is fairly rare... feel better?
Not interested in MOV-based "protection"? Keep reading.
Series Mode (SM) surge suppressors
These were originally designed for the Dept. of Defense, which wasn't happy with the limitations of MOV-based protectors. They are far more reliable and robust than MOV's:
1. SM suppressors have virtually instantaneous reaction speed, nothing gets through above the threshold.
2. Excess voltage is never shunted to ground where it can contaminate the system. When a spike comes in the SM device just opens the circuit. No circuit, no surge.
3. A SM suppressor will probably not wear out in your lifetime. They are not designed-to-fail consumables. SM surge suppressors have no joules ratings because, realistically speaking, they have no capacity limits. There is no practical way to measure the total joules these devices can handle. It would be like trying to measure the amount of water you can pour into a bottomless cup.
For more details about SM surge suppressors:
http://www.digitaltechonline.com/surgeprotect.asp
AFAIK, they are available from just four commercial sources. Compared with the value of your equipment they're not very expensive. I have one on the dedicated circuit that runs my entire HT setup. Cost me about $250 plus an electrician to wire it in. If you prefer a unit that you can just plug into the wall, or even a whole-house unit, they make those too.
Sources for SM surge suppressors:
ZeroSurge (the inventor of the technology)
BrickWall (good value and a sponsor of this forum)
Surgex (wall-based units like mine)
Adcom (audio components with SM protection)
NOTE: your coax lines (cable/sat/antenna) are also pathways for electrical surges. No matter how well-protected your AC lines are, a nearby lightning strike could reach any equipment connected, directly or indirectly, to these other paths. The Adcom units linked above already include coax protection of a kind similar to the units described below. If you chose a ZeroSurge, Brickwall or Surgex you should get one of the following...
AVSForum member jkhome found a $5 coax surge suppressor. Like an MOV, this device apparently takes a limited number of hits before dying but, here's the key, when it does reach its limit it stops passing signal. This is the opposite of what MOV's do, and is much safer for your equipment. Product details are at:
Surgender coax surge suppressor
Video321 adds that, "Radio Shack has an add-on coax surge protector for $10. The model # is 15-1110. The surge life is 5x that of the Surgender and also lists a frequency range of 5 to 2050MHz."
Either of these seems like a good investment if you choose a SM line protector other than an Adcom.
Disclaimer: I don't have trouble changing light bulbs, but I am not an electrician or electrically qualified in any way. The above is based on a lot of careful research when looking for my own surge protection devices.