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cvt
13-09-2005, 01:47 AM
The following posts

i dont have a surge protected powerboard... so i turned mine off cos i really cant be fucked replacing fryed hardware :/

rY*']never had that problem cause of circut breakers ;)


make me sad :(
advertising sells.. and unfortunately the truth is rarely heard...

so read this full post.. and take attention, if you don't beleive me, then eat broken glass and die.



Surge Protected Powerboards

surge protecting powerboards are pointless...

they work by having a MOV (Metal-Oxide Varistor) built into them to snip the tops of small spikes off..

how they work in more detail

240v = nominal
270v = mov threshhold (anything above this gets absorbed)
but they don;t absorb forever.. constant over 270 is instant death
about a 800v spike or more is also instant death to them (and most baords with a light don;t truly indicate whether they are working or not)

ok.. so they filter out 90% of the spikes.. that would stop your computer from crashing... right?
wrong..

most compuet killing spikes are right over 1000v... but why so high?

ALL computer PSU's have MOV's built into them, and in most cases (even with generic and shit brands), a better quality one than you will get in the best powerboards there are.


thinking a powerboard is protecting you is a false sense of security, and if you are thinking it will save your computer from a surge... think again.

there is no true protection from a huge surge.. the best you can get is by using a REAL UPS.. by a real ups, I mean ones like APC's Smart-UPS range..
they actually work by converting the 240v down to the battery voltage, then forming a true sine wave output whenever volatge is not perfect.
they monitor and react quicker than the spike can get through, same with power going out, the moment volatge goes nasty, they switch to battery, wether it be constant high voltage or low voltage, but in those cases, it still runs of 240v (charging batteries), just its not direct from power, but forming a true 240v sine wave output from its 24v/48v batteries.

if a surge biggenough and longenough came thru, it could also kill the ups, first thing that happens is the input fuse blows.. and those batteries absorbed more of the surge than any amount of MOV's ever could..
the equivelent on your computer would have been certain death.
it is still possible to fry all the way thru and kill the computer.. but one that bad.. I've never heard of.

so simply.. don't think that surge protecting powerboard is doing any more than giving you a warm comforting glow of false beleifs.

note: it will save some things.. like mouse chargers, or power packs (most notebook ones are the same as desktop psu) so they arn;t entirely pointless...


last note.. and take attention: a brownout (dropped phase or dullened lights) is more likely to kill your pc, powerpacks, and alike, than a surge a mov would actually save. mov's are used for making power more reliable, absolutly pointless against the true damage dealers!

btw.. 280v constant can kill a PSU, then possibly a PC, the MOV will not last, only small and insatnt spikes are clipped..
by instant, I mean on a 1/4 waveform you could have 20 500v spikes and lift the average voltage 10v.. they arn;t big, any bigger than that and the MOV is dead...


Circuit Breakers / RCD's

circuit breakers don't protect from spikes either.. only over-current, and they typically react in 30->250ms (180ms typical)
so even if the surge has caused overcurrent, by them everything is dead.

RCD's are no different to a circuit breaker under these circumstances.. except that the RCD would probably be dead and need replacing to be effective any longer.

how an rcd works, and what it does

The purpose of RCD'd is to save your life from electric shock.. when a device fails, or save your dogs life when they bite thru the extension cord.
by law they are not required unless.. blah blah blah legal bullshit.. but if you do have them. or are interested, this is how they work
all power going down the active is the same as returning through the neutral, correct? (yes mr. cvt)
so what has happened when this is not the case?
the power has dissapeared somewhere else.. either thru your ugly arse, or alike, or down the earth.
result.. dead/dangerous equipent, tripped/tripping rcd.
it works by 2 small coils, one on the active and one on the neutral, when these become imbalanced, the rcd trips.
brownouts are #1 cause for killing rcd's, and it is quite possible for an RCD to die within 6 months, or last for years and years..
to test them, push the test button, if it doesn't immidiatly switch off, its dead





now please... read and learn.. and if you want real protection, act uppon it properly.
__________________

please don't think doing thos will stop all your computer troubles or make you 100% safe.. it will make you >1000% safer than you are now... but it won't remove all risk..


think about it..

$2000+ PC...
+ you upgrade it how often?!?!

is it really that unreasonable to spend a few hundred protecting your investment (when its a once off)... when it may need $80 of batteried replaced every 4 years for upkeep ?!

plus a good chance your computer will seem more stable... it probably will be if you have bad power (wether you notice it or not).


if you are considering the smart path.. do ask before buying the first one you see.. cos I don't want to see you guys go and buy a battery backup thinking its doing anything more than a extension lead and immunity to blackouts.

Moo
13-09-2005, 01:58 AM
Yeah you shit cunts. USE FUCKING SURGE FUCKING PROTECED BOARDS FUCKING.

I have 6 in here running off each other and all the4se have been working fine.


Whats that smell? BRB.

cvt
13-09-2005, 02:06 AM
tl;dr = eat broken glass and die
__________________

if it eas really that hard to read..
overview =
powerboard = less protection for you pc than the PSU has built into it.. and if you think its protecting you... your about as smart as that smelly shit I dumped into the toilet this morning.
and even dumber than that if you cbf reading the above post.

Moo
13-09-2005, 01:42 PM
tl;dr = eat broken glass and die
__________________

if it eas really that hard to read..
overview =
powerboard = less protection for you pc than the PSU has built into it.. and if you think its protecting you... your about as smart as that smelly shit I dumped into the toilet this morning.
and even dumber than that if you cbf reading the above post.


TLDR.

*NoN*Da]rY*
13-09-2005, 01:46 PM
i never said i didnt use a UPS aswell as breakers ;)

cvt
13-09-2005, 03:46 PM
i know you said you used a UPS earlier.. ;)

dominatrix
13-09-2005, 04:15 PM
good job cvt. im gunna check out maybe gettin a ups.

cvt
13-09-2005, 06:51 PM
just make sure you ask me before buying one if you go something other than APC's Smart-UPS series.. as most UPS's are actually SPS's (or glorified SPS's), and offer no protection oher than battery backup (power goes out)

and make sure you get one biggenough.. 600va+ would be a minimum for a decent PC with a CRT monitor.


I run a 3000va, off of it I have 2 normal pc's (lcd's), a server, 2 printers, and my desktop (and lots of periphials).
it runs a 8 battery system (with a plug for adding up to another 32 batteries on it) and I get about 45min runtime after power goes out and everything is turned on.
don;t be scared buying second hand, unless the issue is something other than 'only lasts a few min on batteries'

batteries are cheap if you know where to go (I pay $18-$28 a battery, for brandless to panasonics, most electical hobby shops charge about $40 ea for no brandys.. so shop around for batteries if going second hand, but a 600va usually only has 1 battery.

va is not watts.. so research or ask if unsure what you need.
if your monitor consumes 80w, and you have a 250w psu. and nothnigelse.. smaller thank 600 would do..
but if you have,and need taht 550w psu, and have a monitor that draws 80w..
well, if I plug my computer into a 700va UPS, it shuts down from overload on startup.
yet I used to run a std computer, server and printer off it (before I got the 1 tonne rackmount)
__________________

reccomended for a single average computer

http://www.apc.com/resource/include/techspec_index.cfm?base_s ku=SC620I

if you want power out runtime, get bigger.
if 390w isn't enough, get bigger.

Elitest_McDenial
13-09-2005, 08:17 PM
I have a couple of q's
What causes a surge to be so long that the protector has to kick in or the wire burns out(old houses have fuse wire)????
second are you talking about the sine wave peak being 800v or the RMS being above 800v?

cvt
13-09-2005, 09:57 PM
surges are usually around 1.5s, causes are many reasons..

the most common reason for a surge is if your on the same line as a large workshop (or smetering plant for best example) and they shut off.
also its common for people on lines which are mainly industrial to get constant voltages around 260v (rms) after business hours.

i was saying that a circuit breaker/fuse wire was no protection at all, not that it would blow from a surge, but that if it did, then everything, as in, everything would be fried.
circuit breakers are like fuses.. in that a 10A fuse may run at 11 amps for hours, and if its sitting at 11A, and a surge (for we'll say the std 1.5s) was to increase it 50v (rms), depending how ohmic the equipment is connected, the current draw will go up, hence, the fuse would blow/circuit breaker trip..
also under lightning strike and a hige voltage down the lone can burn house wiring, is that then not possible to blow the fuse wire simply because it wasn't longenough?
I was pulling examples of extreme cases..

when I mentioned 800v spike.. I was meaning exactly that...
you are confusing surges with spikes.

a single wave is what? about 17ms
a surge may last for several full waves, or even seconds
a spike is under a millisend.
__________________

and don't go and quote exact numbers of spikes.. if your getting that perticular your indeed mcdenial.

spikes can be any size...
there arbitry figures, go check the datasheets on a MOV and see what there limits are..
there are MOV's out there capable of 10,000v or more spikes, but same deal, 280v RMS for 1/2 a second would destroy them.

when we did the study on mov's we looked at the mov in an arlec powerboard, and its specs were along the lines of most of them.
huge volates (over 1000) thay can catch, but a series, or long spike, 800v and they cark it.
270v is the threshold of most MOV's you will come across in devices, and they can arrest a small amount of a surge before burning out.


funny thing is you know how hard it is to burn a fuse wire..
that lovely MOV is active light is on a fuse.. the fuse haves to burn out for it to go out.. nothing to do with wether the MOV is alive.

Elitest_McDenial
14-09-2005, 06:06 PM
ty
and the reason I ask is I had a surge pretector on my old compy and it still got fried so I know they can be just show

cvt
14-09-2005, 07:01 PM
np,
Unfortunately they are just show.. there like any other gimmick that they think will sell more of thee items at an extremely inflated price.

One almost as effective was the crystal holden put in there cars...
Less fuel,more power, more reliable, more responsive.. :o
and it sold (for a very short time)

just the surge protecting powerboards never dissapeared and never got bad named like they deserve :(



*price of a MOV's, 40c -> 1.90 when buying 1 of's
price is way under half that when buying 1000's

your getting a 10c neon, 30c mov, and extra plastic for your extra spent money. :(