Welcome Guest.   Make a donation to an author on the site April 23, 2014, 11:45:07 AM  *

Please login or register.
Or did you miss your validation email?


Login with username and password (forgot your password?)
Why not become a lifetime supporting member of the site with a one-time donation of any amount? Your donation entitles you to a ton of additional benefits, including access to exclusive discounts and downloads, the ability to enter monthly free software drawings, and a single non-expiring license key for all of our programs.


You must sign up here before you can post and access some areas of the site. Registration is totally free and confidential.
 
Read the Practical Guide to DonationCoder.com Forum Search Features
   
   Forum Home   Thread Marks Chat! Downloads Search Login Register  
Pages: Prev 1 [2]   Go Down
  Reply  |  New Topic  |  Print  
Author Topic: Battery Backup - Get One  (Read 11194 times)
westom
Participant
*
Posts: 19

View Profile Give some DonationCredits to this forum member
« Reply #25 on: June 07, 2009, 03:48:24 PM »

In Holland any electrical installation you can think of has to be grounded...by law. Insurance companies don't even pay if your house burns down because of an electrical failure if no proper grounding is in place.
Earthing has long been required everywhere.  However surge protection in the US required earthing that both meets and exceed post 1990 National Electrical code requirements.    A date that suggests how many homes still have woefully insufficient earthing.

  An example.  One FL couple had lightning repeatedly strike an outside bathroom wall.  They installed lightning rods.  Lightning again struck that bathroom wall.  Why?  Lightning rods were only earthed in sand with 8 foot (3 meter) ground rods.  Bathroom plumbing made a better connection to deeper limestone.   Lightning avoided ightning rods to obtain a better connection to earth.

  For surge protection, earthing also must be single point (as demonstrated why in a previous post).  Ufer grounding or equivalent is routine in FL due to poorer conductive sand and the higher frequency of surges. And then all incoming utilities are earthed short, no sharp bends, etc to that single point earth ground.  If the cable enters from the other side, then the house has been setup to have surge damage.

  Circuit breakers never stop damage.  A circuit breaker's function is to disconnect power after something has failed.  Protection of human life from fire created by already existing damage.

   Now put numbers to it.  A circuit breaker takes tens of milliseconds to respond.  A surge is done in microseconds.  300 hundred consecutive surges could exist and the circuit breaker still never trips.

  A circuit breaker would stop or block what three miles of sky could not?  Of course not.  Never happens.  That damning fact defines the difference between effective protection (ie a 'whole house' protetor or why nothing inside the church was damaged) verses a protector that magically absorbs surges.  The one factor that defines even how good a protector is – earth ground.  No earth ground means no effective protection.  A protector is only as effective as its earth ground.

  This is not popular in retail stores where such protectors (and earthing) are not sold.
« Last Edit: June 07, 2009, 03:50:58 PM by westom » Logged
Shades
Member
**
Posts: 1,553


see users location on a map View Profile Give some DonationCredits to this forum member
« Reply #26 on: June 07, 2009, 04:28:30 PM »

@westom:
After taking a look you were more or less right about reaction times, however I found a schematic (near the bottom of the page) which explains better what I meant. The page I link to is translated by Google, the original is in Dutch.

If you don't want to read, the best reaction time is 1.2 µsec, which is a lot faster than the values you suggest. Then again, in that region of Holland there were only two ways you were without electrical power:
1 - because of your own stupidity (creating a short)
2 - failing/forget to pay the bill

The electrical grid over there is great and is one I sure miss here in Paraguay (where the grid still uses 110 volt and people stare at you sheepishly when talking about grounding and 'noise-free' power without fluctuations). 
Logged
westom
Participant
*
Posts: 19

View Profile Give some DonationCredits to this forum member
« Reply #27 on: June 07, 2009, 05:13:42 PM »

After taking a look you were more or less right about reaction times, however I found a schematic (near the bottom of the page) which explains better what I meant. ... the best reaction time is 1.2 µsec
  Your citation is more commonly known as a GFCI or RCB.  If the outgoing current does not match the incoming current, then the breaker assumes a human is being shocked – and cuts off power.

  Will a switch stop a surge?  Of course not.  Surges are currents whose voltage increase, as necessary, to blow through any blocking device.  Why do surges find no problem conducting through 3 miles of the most non-conductive material – air?

  Furthermore, switches always take milliseconds.  Even fast blow fuses take milliseconds.

  To do 1.2 usec, the power must be controlled by semiconductors.  That means the blocking ability is even less.

  Appreciate what it is blocking?  A constant voltage of 240 VAC.   Surge voltages typically go to 6000 volts when something tries to stop the surge.  Your source says the electronic device must withstand 6000 to 8000 volts. That is not stop it.  That is survive a current pulse that, if stopped, could generate those voltages.  The standard solution – to not block those currents so that a massive voltage is not created.  Not block as in let the surge go where it wants to.  Don’t try to do any surge protection.

  GFCIs, et al have become standard in the industrial world since first demonstrated in the 1960s.
Logged
Stoic Joker
Honorary Member
**
Posts: 4,880



View Profile WWW Give some DonationCredits to this forum member
« Reply #28 on: June 07, 2009, 05:39:31 PM »

  A nearby utility pole strike is discharged through all routes to ground (e.g. houses on the block). Being spread out lessens its impact on any one individual dwelling. … If however the strike hits (a tree towards the back of the house (opposite the service entry point) the system is effectively back fed which puts a rather different spin on the proverbial ball.
  Exactly.  Slowly we are working towards reality.  Apparently you don’t realize the ground rod must be the single point earth ground.   Again, you are too quick to challenge rather than learn the significance of what you have just posted.    Failure to install the single point earthing means a struck tree is also a direct connection to household appliances if the building earthing is performed incorrectly.

  So why would you have damage?  Follow the current from cloud to earth.  Down to the tree, through earth, up the ground rod, into the building through appliances, out the other side of the building via improper earthing, then miles to those distant charges.  That is why homes are routinely built or upgraded with Ufer grounds or equivalent.

You can’t have it both ways… You are saying the a strike (which in your world is a single focused point) hit a (soaking wet) pine tree (which has a 30-40 foot tap root), but decided to completely ignore its already being deep underground and decided to come back up through a ground rod which is on the (lengthwise) opposite end of the house (next to the supply line) … and exists for the sole purpose of directing surges downward?

You insist on assuming I’m sitting on a sandy “bad ground” but given the prevalence of lime rock mines in the area that’s not actually so much the case. Not to mention that being a fan of Power-Line networking, which is dependent on a good system ground I’ve taken the time to go over (e.g. reseat & tighten) all of the grounds in the panel for the purpose of creating a good performance baseline when testing equipment (which is part of my job). And no (before you go off on a tangent) I was not using any of that type of equipment at the time.

Quote
  Moving on, you are confusing big with effective.   All that AC mains conditioning equipment has little involvement with surges.  It mostly addresses other problems including harmonics, brownouts, blackouts, and noise.
Hm… Strangely, that’s not what the engineer giving the tour said … but hay it’s your story.

You I gather work with antennas & communications equipment (given the nature of most of your links). In that environment any hit is always direct because you’re dealing with a 100’ tall metal stick poking out of the ground which makes for a single point of contention. Residential areas aren’t quite that neat. It’s generally more of a ground swell that culminates in two cones (one point up, one point down) meeting in the sky. Who gets how much of what becomes rather random at that point.

Once again I’ll refer to my airbag analogy in simply stating that a UPS can help.
Logged
westom
Participant
*
Posts: 19

View Profile Give some DonationCredits to this forum member
« Reply #29 on: June 07, 2009, 06:42:56 PM »

You can’t have it both ways. You are saying the a strike … hit a … pine tree (which has a 30-40 foot tap root), but decided to completely ignore its already being deep underground and decided to come back up through a ground rod which is on the (lengthwise) opposite end of the house … and exists for the sole purpose of directing surges downward?
Again you are making assumptions rather than read what was posted.  Did you see the phrase about earthborne charges miles away?  Apparently not.  Without understanding the principles, then you misrepresented what was posted; did not grasp what was posted.  What was posted has been understood for most of the last 100 years.  There is no contradiction.  But there is a reader who is having difficulty dismissing and forgetting the myths he once believed.

  In one location, surge protection was properly installed.  Damage occurred.  Why?  In earth were veins of graphite.  Since earth was not monolithic, protection system (earthing) needed upgrading.  They had what you have described – pockets of more conductive earth.

  Tightening grounds is nice.  And does little for better earthing.  For example, how does the 6 AWG ground wire connect to a ground rod?  Up over the foundation and down to that rod.  Sufficient to meet code.  And insufficient for surge protection.  That ground wire must go through the foundation and down; to be shorter, no sharp bends, separated from other wires, etc.  

  Meanwhile a lightning strike to the tree could have also forked off into AC electric, buried power line, etc.  Most all strikes leave no apparent indication.  With questions, we eventually discover they had no idea where lightning struck.  They assumed  - then converted assumptions into fact.  Same problem is repeated often in this thread.

  I provided only a sample of reasons why you had damage from a struck tree.   As a novice, you might finally begin to learn this stuff in highly regarded application notes from Polyphaser:
  http://www.polyphaser.com/technical_notes.aspx
Warning: this may be tough reading if too attached to many erroneous myths.  Too many make assumptions and therefore need to reread it more often.  You see contradictions only because you have not grasp some basic concept.

  From information provided, your had damage because and the solution begins with earthing.  If earth has pockets of more conductive earth (lime rock mines) or if a major pipeline passes nearby, then your earthing needs additional improvements.  If at the end of a AC distribution system approaching from the west, then frequency of damage would be even higher – more corrections required.  How to do this is more complex.  But the description of your damage is typical of bad earthing and no ‘whole house’ protection.

  Most homes are still built as if transistors do not exist.  Surge protection starts when footings are poured.  Many supplement a weak protection system with compromises.  Some foolishly think a cold water pipe entering on the other side of the basement is good earthing.  Wrong – for so many reasons posted previously.

  Bottom line in any facility: if damage results, then corrections start with a study of earthing.
« Last Edit: June 07, 2009, 06:44:46 PM by westom » Logged
Stoic Joker
Honorary Member
**
Posts: 4,880



View Profile WWW Give some DonationCredits to this forum member
« Reply #30 on: June 07, 2009, 07:53:35 PM »

Enough is enough, Judging by your joined on date & first post you joined this board for the sole purpose of launching a rather highhanded & condescending attack on me. For the “crime” of sharing the events of my day with fellow members. Your imperialistic attempts at making me look stupid have only succeeded in impressing me with your arrogance.

Feel free to enjoy your “win”, as I will not be returning to this thread.
Logged
4wd
Supporting Member
**
Posts: 3,222



see users location on a map View Profile Read user's biography. Give some DonationCredits to this forum member
« Reply #31 on: June 07, 2009, 10:20:48 PM »

@bob99 - We're on the same page man, just different paragraphs... You're talking about a proper surge device that actually has power conditioning circuitry. I'm talking about one of those Cheap-O power strips (that most end users seem to end up with) that only has a breaker in it.

Almost all 'cheap-o' surge suppressors I've seen, (or have), use MOVs because they're cheaper than circuit-breakers.

A typical cheap surge suppressor circuit is, (taken straight off one I just pulled apart):



If a sufficiently large surge gives the MOV a hard time, it will, generally, go short-circuit thereby turning on the LED and thus giving a failure indication.

If your strip has a circuit-breaker then I'd take a pretty fair guess that the circuit-breaker is there for output current overload protection.  A thermal circuit-breaker is just too slow for surge suppression use.

If you open it up I'm sure you'll find a MOV is across the line to do the actual suppression.

In Australia, I believe it was regulated that all power-boards, (power-strips), have a circuit-breaker to guard against output current overload.  Previously they didn't and there were some reports of fires starting by people plugging too many things into power-boards, IIRC.  I'd be surprised if America didn't have a similar regulation.

Enough is enough, Judging by your joined on date & first post you joined this board for the sole purpose of launching a rather highhanded & condescending attack on me. For the “crime” of sharing the events of my day with fellow members. Your imperialistic attempts at making me look stupid have only succeeded in impressing me with your arrogance.

Feel free to enjoy your “win”, as I will not be returning to this thread.

Your reply to westom came in while I was typing away at this and I was then in two minds as to whether to continue or not.  As it is, maybe someone will find my post relevant - so here it is.

EDIT: Stupid me, I got my circuit round the wrong way  embarassed
« Last Edit: June 07, 2009, 10:27:23 PM by 4wd » Logged

Four wheel drive: Helping you get stuck faster, harder, further from help...........and it's no different on this forum Evil
westom
Participant
*
Posts: 19

View Profile Give some DonationCredits to this forum member
« Reply #32 on: June 07, 2009, 10:24:30 PM »

Enough is enough, Judging by your joined on date & first post you joined this board for the sole purpose of launching a rather highhanded & condescending attack on me.
 You have assumed attacks.  I have been trying to get you to stop thinking failure is acceptable.  I have been trying to explain why you had damage that was never acceptable.  That the battery backup did not protect the computer – just like the manufacturer specs state.  And I have been trying to get you to install what is all but required in every FL building.  Required but not always installed especially in pre-1990 buildings.

  I have not attacked you - ever.  But I have been bluntly honest.  How many engineers have provided a solution AND explained why that solution works – with numbers?    You have taken information that is too new to grasp (for now).  Then assumed that was an attack.  No.  You have a bias as entrenched as the many who just knew Saddam had WMDs.  Many take personally what is only the fact when that fact contradicts what was always assumed.

  Hopefully you will appreciate what has just happened here.  I am trying to demonstrate why the popular myths are wrong.  How protection is routinely installed to not have damage even from direct lightning strikes.   You had damage.  That is a completely failure of any protection you thought you had.  And the effective solution costs less money.   A majority routinely deny this reality, in part, because the concept is just too new - even if these principles have been well established and routine for over 100 years.  Deny for the same reasons why so many *knew* Saddam had WMDs.

  Notice how many posts are based in radio communication.  That is where most of the original research was conducted AND where the best experience is learned that applies even to munitions dumps and homes.  Either you can aggressively deny what has long been the well proven technique.  Or you could ask for further clarification and assistance.  Why?  Because the effective solution means no damage no matter what lightning strikes.  And that solution also means others lesser surges are irrelevant – do not cause damage.

  Your choice.

   Meanwhile, others can either learn from your denials or learn from your curiosity.
Logged
westom
Participant
*
Posts: 19

View Profile Give some DonationCredits to this forum member
« Reply #33 on: June 07, 2009, 10:44:33 PM »

Almost all 'cheap-o' surge suppressors I've seen, (or have), use MOVs because they're cheaper than circuit-breakers. A typical cheap surge suppressor circuit is, (taken straight off one I just pulled apart):
That circuit is incorrect.  View MOV datasheets.  Leakage currents are well below 1 ma.  An LED requires at least 10 ma.  Furthermore, 1 milliamp through an MOV is a test current for its threshold voltage - a voltage well above what should be on AC mains.

  Circuit breaker does nothing for surge protection for so many reasons.  CB is a device required for every power strip – with or without protector circuits. Installed only for human safety.

 Thermal fuse is required so that a failing (grossly undersized) MOV does not create fire.  Thermal fuse disconnects MOVs long before an MOV conducts anywhere near what might be its maximum protection.  Sometimes the fuse does not work which is why most fire departments have been called for protector fires.  Problems detailed in so many previous examples and in Norma’s quoted experience.

  MOV is effective if it has something to divert surge energy into.  That means a low impedance (ie ‘less than 3 meter’) connection to single point earth ground.  No earth ground means no effective protection.  No earth ground means a protector may divert that surge destructively inside the building – maybe destructively though some appliances.

  Meanwhile your circuit is incorrect – is missing other critical connections.  Your assumption is that the MOV can fail catastrophically.  As repeatedly noted, that is not an acceptable failure mode.  Again, read page one of every MOV datasheet.

  How is the light connected?  See the picture where all MOVs are removed – and the light says that protector is still good:
  http://www.zerosurge.com/HTML/movs.html
Logged
Shades
Member
**
Posts: 1,553


see users location on a map View Profile Give some DonationCredits to this forum member
« Reply #34 on: June 07, 2009, 11:51:08 PM »

@westom:

Maybe you can shed a light on this matter for me as well (at least if you don't mind explaining). But first I should thank you for the tip of the ground line through the foundation instead of cornering around it. I know for a fact that this happens a lot on construction sites.

Ok, the question. I was always told that you will improve grounding tremendously by creating a diamond (similar as in playing cards) with grounding poles. The distance between poles should be calculated because the type of earth has an effect on the calculation as well as the angles from the diamond shape.

Is the diamond also a myth?

Oh, you would likely understand it already but I should mention that the connecting lines between the poles also are in the earth and not "switched" in the electric closet. Each house in Holland has a special closet inside the house that holds the meters for energy consumption (electricity, gas and water), circuit breakers, grouping switches and main water valve. Most of the times the land based telephone line and cable (TV/radio) are also coming into the house through that closet.
Logged
4wd
Supporting Member
**
Posts: 3,222



see users location on a map View Profile Read user's biography. Give some DonationCredits to this forum member
« Reply #35 on: June 08, 2009, 01:05:16 AM »

Almost all 'cheap-o' surge suppressors I've seen, (or have), use MOVs because they're cheaper than circuit-breakers. A typical cheap surge suppressor circuit is, (taken straight off one I just pulled apart):
That circuit is incorrect.  View MOV datasheets.  Leakage currents are well below 1 ma.  An LED requires at least 10 ma.  Furthermore, 1 milliamp through an MOV is a test current for its threshold voltage - a voltage well above what should be on AC mains.
Aaargh!  You're right, next time I'll grab some glasses - corrected circuit:



Quote
Circuit breaker does nothing for surge protection for so many reasons.  CB is a device required for every power strip – with or without protector circuits. Installed only for human safety.

ummm, yes - as I stated.

Quote
Your assumption is that the MOV can fail catastrophically.  As repeatedly noted, that is not an acceptable failure mode.

No offence but while it may not be an acceptable failure mode, it is a fact of life.  Everything is subject to catastrophic failure no matter how well engineered or designed it is.  The fact that something hasn't failed catastrophically is simply due to not having the right circumstances in place for it to occur.

EDIT: And as a side note, it shows you how cheap they make these things because that really isn't a good way to power an LED from 240V - the resistor dissipates for more power than is necessary all because they don't want the added expense of a mains-rated capacitor.
« Last Edit: June 08, 2009, 01:20:08 AM by 4wd » Logged

Four wheel drive: Helping you get stuck faster, harder, further from help...........and it's no different on this forum Evil
westom
Participant
*
Posts: 19

View Profile Give some DonationCredits to this forum member
« Reply #36 on: June 08, 2009, 01:45:06 AM »

No offence but while it may not be an acceptable failure mode, it is a fact of life.  Everything is subject to catastrophic failure no matter how well engineered or designed it is. 
And airplanes don't crash.  Why is an airliner crash international news?  Because the event is so close to zero as to be virtually zero.

  Catastrophic failure is unacceptable because house fires are unacceptable.  Still, they happen.  So we installed things that 'virtually' do not suffer catastrophic failure - ie 'whole house' protectors.  And locate them where failure is less likely to create fire - ie service entrance.  Plug-in protectors have a (relatively) high failure rate (which is why another international standard is forthcoming) and get located where fire risk is higher.

  Why is that failure rate so high?   Failures promotes sales.  "My protector sacrificed itself to save my computer."   Some protectors are designed to maximize profits - not protection.  Take a $3 power strip.  Add some $0.10 parts.  Sell it for $25 or $150.

  Anything they can do to make that fuse trip faster means less fire threat - and even more promoting the protector.  But limits exist. If the fuse blows too easily, then it does not even quality as a protector in UL or equivalent 'human safety' testing.

  Meanwhile, your fuse must be in the wrong spot. That thermal fuse must extinguish a light when it blows. More often, that light is a Neon glow lamp.  Easier to power on 240 volts.


Logged
OldElmerFudd
Charter Member
***
Posts: 181


Bite-sized trouble

see users location on a map View Profile Read user's biography. Give some DonationCredits to this forum member
« Reply #37 on: June 30, 2009, 02:05:58 AM »

Truly interesting discussion. Thanks, everyone!

I've been using a Cyberpower CP1500 with the LCD screen for the home office machines, and an APC BR1500 for the server. Both have been running without problems for the last couple of years. I keep an older APC 850 to use with a machine dedicated to audio work; there's seldom any load on it. I've had battery backups since I built my first 486 machine, and yes, surge protectors as well.

Lightning isn't the issue here in Los Angeles; I'm more concerned with having equipment bolted down when the ground shakes!
Logged

Always code as if the guy who ends up maintaining your code is a violent psychopath and knows where you live.
Tinman57
Charter Member
***
Posts: 1,697



Duck! It's another MicroSoft Patch!

View Profile Read user's biography. Give some DonationCredits to this forum member
« Reply #38 on: July 01, 2009, 08:28:37 PM »

  Let's see, my electric goes through three fuse boxes, my computer system is on a battery backup plugged into a voltage regulator to prevent the battery backup from constantly switching from online to offline while on generator power.  I think I'm pretty well protected...  Wink
Logged

((((TINMAN))))
westom
Participant
*
Posts: 19

View Profile Give some DonationCredits to this forum member
« Reply #39 on: July 02, 2009, 05:40:08 PM »

  Let's see, my electric goes through three fuse boxes, my computer system is on a battery backup plugged into a voltage regulator to prevent the battery backup from constantly switching from online to offline while on generator power.  I think I'm pretty well protected...  Wink

  You may be protected.  But your electronics are not.  Fuses do  not protect electronics or appliances.  Fuses only stop fires from happening after the damage has been done.  Fuses, circuit breakers, etc are only for protecting human.  Even the UPS does not provide and does not claim to provide appliance protection.

Logged
Stoic Joker
Honorary Member
**
Posts: 4,880



View Profile WWW Give some DonationCredits to this forum member
« Reply #40 on: August 27, 2009, 10:40:14 PM »

So, having it on the highest of authorities that only a pristine ground is needed to heal all woes. I refrained from replacing the derisively referred to as a "Plug-in Protection" device with its evil hollow claims to defend my server from anything ... Even tho I am well aware that the hicks around here just love to flick the power on & off now and then; not to mention letting the line voltage crawl around like a moth on crack. Just to see what would actually happen (as if I didn't already know...).

Completely ignoring the fact that my previously flawless (5 year running) 99.995% uptime record immediately plunged to 70 something. I waited until I had a better more conclusive looking number, which I've attached below:


Hint: The Zero Byte .vhd file used to be an 8GB Windows 2003 Mail Server. Now a through diagnostic of all hardware clearly shows that there is absolutely nothing wrong with any of the hardware. It is all in perfect (physical) working condition. Unfortunately the excessive number of soft errors caused by (randomly) power cycling the box while under load had a rather adverse effect on the file system.

Hence I will at this point happily concede that with "proper grounding" no physical harm can or will befall ones computer. Which IMO would be an absolutely flawless conclusion, except for one minor detail ... The damn thing ain't decorative. Having a large chunk of ones data completely trashed is (sadly...) just not an acceptable outcome.

So thus ends my do servers really need clean power experiment...
Logged
Pages: Prev 1 [2]   Go Up
  Reply  |  New Topic  |  Print  
 
Jump to:  
   Forum Home   Thread Marks Chat! Downloads Search Login Register  

DonationCoder.com | About Us
DonationCoder.com Forum | Powered by SMF
[ Page time: 0.051s | Server load: 0.02 ]