Overvoltage (not a surge) killed all my electronics (How to prevent this???)

[bwithers]

Recently my power company "decided" to send waaay too much voltage to our whole block. The power transformer for our block failed, but before it died it looks like it was sending a constant 220V AC to our house. This fried my big screen TV, Tivo, new receiver, powered sub, VCR, digital cable box, garage door opener, and cordless phone (along with some other misc. stuff).

Yes, they were all plugged into a decent quality surge protector and no they were not even turned on! I'm an EE (a chip guy, not a "real" EE ) and I got a good review (lesson) on how a surge protector and fuses work. Even the best surge protector will only protect again voltage spikes of 330V and above (not constant 220V). Fuses will only blow due to excess current. The only thing that would help in this case seems to be either a UPS or some kind of power conditioner that would electrically isolated the components from the wall power.

The good news is it looks like the power company will reimberse me to have the stuff repaired. The form says they will pay the repair cost or fair market value (whatever is lower). However, the claims agent says they may pay replacement costs on a case by case basis.

Anyways, It seems like it would take a pretty beefy UPS to be able to handle all the power required for my home theater. The one's designed for computers will likely not cut it (although I admit I haven't researched this). Any suggestions out there?

[edtyct]

PS Audio manufactures protection for situations like yours. I recall that some of their units have an adjustable voltage peak to automatically shut down your system, and they are advertised as dealing with overages. One site where at least some of the PS Audio power conditioners, and others, are described and sold is audioadvisor.com. Unfortunately, they aren't cheap, but if you can afford one, and it saves your neck down the line, it will have been money well spent.

Ed

[Boltergeist]

Tripp Lite makes some reasonably priced power conditioners. Here is one that will maintain 120v from 89-147 volt range. I think i saw it for about $100.
http://www.tripplite.com/products/pr...productID=2010
I've been looking at some of these, but haven't made a purchase yet. An under voltage can cause problems too. also, if you have homeowners coverage, that coverage is typically replacement cost, in case you have older gear that may get overly depreciated. good luck.

[PAT.P]

Here are a few site www.energyon.com , www.apc.com and there a discontinued items at http://factoryoutlet.apc.com ( USA ) .There is a product they sell called RESIDENTIAL SURGE SUPPRESSION it is connected at fuse or breaker box .Pat.P

[Glen B]

Furman Sound makes a range of voltage regulators with overvoltage protection. See the link I have provided below. Take a look at the information on their products and you are sure to find a model to suit your needs and wallet. There are many Internet dealers that sell Furman products at significant discount.

Furman voltage regulator: http://www.furmansound.com/products/pro/reg/reg2.php

[bwithers]

Thanks for all the responses. I now have some leads to research.

I have a $1000 dollar deductable on my homeowners insurance and a claim will cause the premiums to go up. My stuff really isn't that high end so I'm better off going the power company route first. Luckily everything major was able to be repaired so far (except the VCR and garage door opener which I have replaced).

[bwithers]

Tripp Lite does seem to have a good price for what I need on their LCR2400.

http://www.tripplite.com/products/pr...productID=2832

Can anyone think of any reason not to get this one?

[edtyct]

I'd forgotten about Tripp-Lite. It was one of the first companies to offer heavy protection. I seem to remember their products being much more expensive than they appear to be now. The LCR2400 looks good to me. It does everything that I can imagine being necessary. If it handles your load, your number of components, your geography, and your budget, it looks good to go.

[Glen B]

Tripp Lite does seem to have a good price for what I need on their LCR2400.

http://www.tripplite.com/products/pr...productID=2832

Can anyone think of any reason not to get this one?

There is nothing in the Tripp Lite specs to indicate that the unit shuts power off at any point when experiencing a high line voltage. Check before you buy. The Furman units shut power off at any line input greater than 150 volts, protecting your equipment. When you factor in the voltage reduction in the Furman units, your equipment should see no voltage greater than 130V (within safe operating range) at the point of shutdown.

[bwithers]

You're absolutely right Glen! I had to reread it again. It claims overvoltage protection, but nothing about out of range voltage power shutoff like in the Furman units. That would be a key feature. I feel silly for overlooking that!

[bwithers]

I'm looking at getting the Furman AR-1215 after Glen pointed out the key missing feature of the Tripp-Lite.

http://www.furmansound.com/products/pro/reg/reg1.php

[edtyct]

My understanding is that the Tripp Lite does have a power shutdown circuit breaker. In fact, I thought that just about all power line conditioners did. Hmmm.

[Glen B]

My understanding is that the Tripp Lite does have a power shutdown circuit breaker. In fact, I thought that just about all power line conditioners did. Hmmm.

A circuit breaker by itself will not protect against overvoltage (as evidenced by the fact that in bwithers' case, fuses/breakers in his components and household branch circuit breakers did not open to prevent damage). A circuit breaker is an overcurrent device (opens in the presence of excessive current flow -- which may range from instantaneous to several minutes depending on its ratings and the duration of the overcurrent). Apparently, the Furman voltage regulators have circuitry that will sense "continuous" input voltage above 150V and shut the unit down.

[Boltergeist]

A question i had on the Tripp lite was whether it could handle the load. The Tripp lite is rated at 5 amps, 600 watts. The Furman is rated at 15amp, and i did not see watts listed, but i think their units are out of my price range. Anyone have experience in this regard on whether the Tripp lite should be able to to handle the load of a basic HT set up?? Big screen tv, hk avr 235 (which states is has high instantaneous current capacity of +/- 35 amps??) 50 watts x 7 but the specs say 890 watt max power consumption. Nameplate on my sub says its 230 watts. some i'm not sure how these specs translate to real world power needs???

[edtyct]

Glen, a question: Presumably, the Tripp Lite and other conditioners will stabilize low or high voltage, bringing it back within a certain range as necessary, though it may reduce current (amps). Will not that kind of circuitry, in combination with a good circuit breaker for extraordinary surges, do the trick? I'm asking because I don't know.

Ed

[Boltergeist]

Here is a faq from Tripp Lite. They state their conditions do protect against surges, which is sort of what I thought. The unit i looked at has 700+ joule rating, which the faq says is exceptional surge supression. so it does not look like you need to put surge protection on top of the conditioner.
http://www.tripplite.com/support/faq/surges.cfm

[bwithers]

Reading the FAQ actually helped:
http://www.furmansound.com/products/.../faqpower1.php

I don't believe I need a power voltage regulator. The PST-8 ($150 MSRP) has power conditioning, surge protection, and extreme voltage shutoff. It looks like this will *protect* against just about anything including the overvoltage situation I had.

The power voltage regulators will keep the voltage right at 120V if the input is withing a certain range. While this may have some performance improvements it won't offer any more protection.

Can anyone else confirm my conclusion?

[edtyct]

I don't know enough to confirm, but I'll keep this alive because there may be other issues. Low voltages can be harmful, too, right? And what about sustained overages that might not qualify as genuine surges--say, at 150V or so? Wouldn't voltage regulation be a valuable way to keep them in line? Another issue is the audiophile/videophile question of how noisy the signal from the power conditioner is--not just whether it can isolate the various connected components from each other but whether its own circuitry negatively affects the signal of, say, DVD players and microdisplays, which apparently are more sensitive than telephones, printers, etc. I've read reviews that have characterized some of these devices as noisier than others, in ways that affects A/V performance. As I said, I don't know enough about them myself, but maybe someone who does can address these issues.

Ed

[Glen B]

Reading the FAQ actually helped:
http://www.furmansound.com/products/.../faqpower1.php

I don't believe I need a power voltage regulator. The PST-8 ($150 MSRP) has power conditioning, surge protection, and extreme voltage shutoff. It looks like this will *protect* against just about anything including the overvoltage situation I had.

Can anyone else confirm my conclusion?

You are correct. The PST-8 should be all you need since all you're looking to protect against is extreme voltage. I did not look at specs for every single Furman conditioner so good for you that you found an inexpensive model that will do what you want.

[Glen B]

Glen, a question: Presumably, the Tripp Lite and other conditioners will stabilize low or high voltage, bringing it back within a certain range as necessary, though it may reduce current (amps). Will not that kind of circuitry, in combination with a good circuit breaker for extraordinary surges, do the trick? I'm asking because I don't know.

Ed

The TrippLite and Furman units compensate for the undervoltage/overvoltage by switching taps on an autoformer. The autoformer is limited in its voltage boost/cut capacity so obviously when the AC line voltage exceeds that capacity, it is necessary to disconnect power to the plugged in components to prevent damage. Circuit breakers protect against excessive current draw only. MOVs or avalanche diodes protect against (momentary) surges. None of the above will protect against longterm overvoltage (likely a second or longer). The only way to accomplish this is to have special circuitry that will detect the overvoltage, open a relay and disconnect power to the plugged in components.

[Glen B]

A question i had on the Tripp lite was whether it could handle the load. The Tripp lite is rated at 5 amps, 600 watts. The Furman is rated at 15amp, and i did not see watts listed, but i think their units are out of my price range. Anyone have experience in this regard on whether the Tripp lite should be able to to handle the load of a basic HT set up?? Big screen tv, hk avr 235 (which states is has high instantaneous current capacity of +/- 35 amps??) 50 watts x 7 but the specs say 890 watt max power consumption. Nameplate on my sub says its 230 watts. some i'm not sure how these specs translate to real world power needs???

The TrippLite at 5 amps does not have enough capacity for an entire HT system. Do you really need voltage regulation ?

[Boltergeist]

i'm not sure. i did lose my power supply to my tv about 8 mos ago, and my receiver died (although it was about 10 yrs old) about 2 mos ago. since then i found a loose connection on a hot leg in that circuit, so i dont know if that was related to any problem or if these failures were just coincidence. anyway, i was only looking to spend about $100, so i was looking for the most sensible protection. i thought maybe volt reg would be better than a power condition/surge protector. i currently have an isotel ultra surge protector, but its old and due for an upgrade. tripp lite does have a 10 amp 1200 watt line conditioner that was $100. http://www.tripplite.com/products/pr...?productID=208
or do you think i would be better off with a surge supressor like this, about $80. http://www.tripplite.com/products/pr...productID=2813.
i appreciate the advice.

[bwithers]

Boltergeist,

Based on my research and my knowledge of electronics, if you want just protection I would go with the Furman power conditioner (PST-8 $100) over the tripp-lite voltage regulator. This is because of the Furman has the extreme voltage protection. If you get an overvoltage with the tripp-lite you are *not* protected. I verifed this by emailing the company. I don't believe that voltage regulation is necessary for the safety fo the equipment. All the equipement should have their own voltage regulators which should work fine.