View Full Version : OG&E Power Surges and Outages



JayhawkTransplant
07-21-2013, 10:15 AM
Hi guys,

My neighborhood has been experiencing upwards of 5 power outages per day for the past few weeks. Dozens of us have reported this to OG&E, and when one neighbor actually talked to a human there earlier in the week, they said they would send someone out to assess the problem.

This morning, the electricity has been going out more than once a minute. My brand new air handler, less than 2 months old, started making loud noises that made me think that the power surges had fried it, so I completely turned off power to everything in my house.

So, I have a few questions:

1) Is this happening to those of you who live outside of the 23rd and May area?
2) If these power surges did indeed fry my compressor, do I have any recourse with OG&E? I have personally reported power surges to them for the last 4 days.

kevinpate
07-21-2013, 10:36 AM
Not to the same level of severity, but OG&E sometimes stands for Oh Gee Power is out again; wonder when it will [wait for it ... dang, call it in, again] in Norman as well. It's usually not spread across the day here. There might be one, or two, sometimes 3+ but it tends to fall within a few hours time span when it happens.

Most common live answer when we have asked ... wind messing with lines. Not that the lines are down, just wind being disruptive. It would probably make more sense to me if I really thought it through, but all I ever get is the mental image of a transmission lines going Yikes! Wind Gust!!?! .. Whoa, scared the juice right outta me. You ok over there Bob? Yeah, scared me too though.

Never had it fry anything, knock on wood.

bandnerd
07-21-2013, 10:52 AM
Power goes out occasionally here, too. I'm not normally home when it happens, but when I turn on the TV or look at the oven clock, it tells me there was a power outage. A few weeks ago, around lunchtime, it went out in the neighborhood for about 45 minutes. It was about 80, sunny, with a light comfortable breeze. There was absolutely no reason for it.

Back home, my house was on the local REA. We didn't lose power as often as the OG&E people. There was, however, one evening when the power went out, and browned-out, repeatedly. We were trying to watch a movie and finally gave up. The next day, word spread around town about what had happened: a snake had gotten into something and was touching things it shouldn't have been touching.

I've also known squirrels to fry out the power by touching the wrong thing. Flaming squirrel, no power.

I am sorry if you have any losses, though, because of the surges. I don't know if you have any kind of case with them, though. That's a question for an attorney.

WilliamTell
07-21-2013, 05:29 PM
Our power went out, we are in NW once north of Hefner

stick47
07-21-2013, 06:00 PM
We have power blinks during the day sometimes here. A friend and neighbor warned me to expect it before we moved in. Most of the events are of such short duration that they'd be easy to miss.

bluedogok
07-21-2013, 08:28 PM
I had power issues when I lived on Independence just south of NW 50th, the issue was the service line that came up the back fence on our little strip (50th-48th, west side of Independence, east side of Woodward). Our power would be out but everyone else around us had power. Never really had a problem with OG&E anywhere else in town, we had many more power issues in Austin.

BBatesokc
07-23-2013, 05:06 AM
We suffered very brief (1-2 seconds max) power outages on a fairly regular basis at our old house - SE 44 Sooner.

It was just enough to reset the DVR and shut my computers down.

We ended up buying some of those battery backup units you can get at Sam's. We then plugged the TV/DVR, computers, etc. into those so they never go off unless the power remains off for about 40+ minutes (which never happened). Plus, it is a power surge blocker so my electronics don't get fried.

Has already come in handy at the new house as the high winds tend to make the power also go off for a second or two on occasion.

bombermwc
07-23-2013, 06:48 AM
OG&E won't pay for issues that come from surges/outages. And if you put WattsDog on your house...it's sort of a waste because they still say they don't cover. They even tell you it's not a whole-home surge protector but isn't that the whole point of the stupid thing? Ugh.

Surge protectors (not just power strips and yes there is a difference) are definitely your friend. But I'll caution you a bit too. Companies like APC (for battery backups) do not cover "acts of god" in their warranty. So you have to be careful in how you discuss the issue that cause the damage. Storms don't count for them.

In the storms last week, we had a flickering outage that finally took everything out. It was rather creepy to see the whole house out, but the TV still trucking away on the battery backup for 40 minutes. At first my wife didn't realize the power was out because it was during smart hours and we had the lights off anyway...lol.

ctchandler
07-23-2013, 11:40 AM
Bombermwc,
I have to question you on this one, the APC warranty does cover your equipment if damaged through their surge protector for all types of power problems, even "acts of god". I am a big user and have used their warranty, and I just got off the phone with them to make sure all of their surge protectors covered equipment damage the same way and they verified that they do. If I misunderstood your point, I apologize.
C. T.

Companies like APC (for battery backups) do not cover "acts of god" in their warranty. So you have to be careful in how you discuss the issue that cause the damage. Storms don't count for them.

old okie
07-23-2013, 01:59 PM
We live in the SW part, south of 104th; power "glitches" here all the time; usually just for less than a second or two, but enough to "blow" some of the clocks, etc. It happens so often in our neighborhood that our HOA sent out a message to be certain to call OG&E EVERY time it happens, as that's what the customer service rep told the HOA folks to tell us to do.

BTW, you can reach a real person by dialing the 272-9595 number and waiting through the computer options to #5, which has always allowed us to reach a customer service rep.

SoonerDave
07-23-2013, 02:31 PM
Bombermwc,
I have to question you on this one, the APC warranty does cover your equipment if damaged through their surge protector for all types of power problems, even "acts of god". I am a big user and have used their warranty, and I just got off the phone with them to make sure all of their surge protectors covered equipment damage the same way and they verified that they do. If I misunderstood your point, I apologize.
C. T.

I think you'll find the APC warranty is against "transients" or "spikes" in the normal course of operation. If you're talking about a direct lightning strike that infiltrates your home wiring (rather than going to ground), there's not a $150 "surge protector" made that will do any good. That's when you get into proper whole-house grounding, which is a subject unto itself that is barely touched around here as far as I can tell.

EDIT: Sure enough, found a PDF copy of their basic warranty and they explicitly exclude "Acts of God." Pretty typical exclusion. Have to suspect similar language is in any of their extended power warranties.

Link: http://www.apcmedia.com/salestools/CFOT-7PVJLF/CFOT-7PVJLF_R0_EN.pdf

ctchandler
07-23-2013, 04:42 PM
SoonerDave,
The way I read it, it has to do with their SmartUps products, not their surge protectors. I have the SmartUps and it has several plugins for the uninterruptible power supply and several that are surge protection only. Regardless, I am going to call them again and verify that. I have already been reimbursed for an "act of god", so it's obvious that there is something strange about this.
C. T.

I think you'll find the APC warranty is against "transients" or "spikes" in the normal course of operation. If you're talking about a direct lightning strike that infiltrates your home wiring (rather than going to ground), there's not a $150 "surge protector" made that will do any good. That's when you get into proper whole-house grounding, which is a subject unto itself that is barely touched around here as far as I can tell.

EDIT: Sure enough, found a PDF copy of their basic warranty and they explicitly exclude "Acts of God." Pretty typical exclusion. Have to suspect similar language is in any of their extended power warranties.

Link: http://www.apcmedia.com/salestools/CFOT-7PVJLF/CFOT-7PVJLF_R0_EN.pdf

Jim Kyle
07-23-2013, 05:29 PM
Here's another clip from the APC web site at http://www.apcmedia.com/salestools/KBOK-77ZRQH/KBOK-77ZRQH_R0_EN.pdf (emphasis added):

If your electronic equipment is damaged by power line transients on an AC power line (120 volt) while directly and properly connected to a standard APC 120 volt product covered by the Equipment Protection Policy ("connected equipment"), and if all of the remaining conditions specified below are met, APC will, at APC’s sole option, during the period specified below, replace the APC product and either (a) pay for the repair of the equipment or (b) reimburse you for the fair market value, as determined by the then current price list of the Orion Blue Book (or equivalent), of the connected equipment, in an amount not to exceed the dollar limits stated below, if APC determines that the damage was caused by the failure of the APC product to protect against power line transients, (telephone line, network, or CATV transients, if applicable).

Power line transients that APC products have been designed to protect against, as recognized by industry standards, include spikes and surges on AC power lines (not designed as protection against swells as defined by IEEE 1100-1992).

There's quite a bit more than I've quoted, but no more exclusions, just details about phone lines, CATV lines, network cables, and so on. The limited warranty on the surge suppressor described at the site to which I link above is also "lifetime" rather than the times shown on the UPS warranty page.

bluedogok
07-23-2013, 10:17 PM
I have battery backups on most of my electronics, most of those are APC and haven't had an issue with them. Some UPS systems work better than others, some have the devices isolated from the plug, always running off battery and the plug charges the batteries, those are the type to buy because of the isolation. I still haven't had an issue with the cheaper APC units and Austin Energy wasn't exactly reliable in our neighborhood.

Prunepicker
07-23-2013, 11:15 PM
Okay, I'm ignorant on this thread. What is APC?

ljbab728
07-23-2013, 11:27 PM
Okay, I'm ignorant on this thread. What is APC?

Hand over mouth, LOL.

bombermwc
07-24-2013, 07:24 AM
Bombermwc,
I have to question you on this one, the APC warranty does cover your equipment if damaged through their surge protector for all types of power problems, even "acts of god". I am a big user and have used their warranty, and I just got off the phone with them to make sure all of their surge protectors covered equipment damage the same way and they verified that they do. If I misunderstood your point, I apologize.
C. T.

I say this from experience in calling in for warranty service on them over 10 years of use with APC small battery backups at my office....hundreds of them. Fortunate for me, wheni was first told about the "acts of god" thing, i hadn't yet given the serial number of the device so i just hung up, and called back with an altered story. I had originally called because after a storm, one device had failed and went Red with a beep = bad battery. It was only a month old, so the storm definitely killed it. When i called back in, i just said, "it's not working right. red light and beeping"...just failed to mention the storm.

Personally, i feel like they should have been responsible for it. Especially given how many we own....come on. On the same hand, i can count on 1 hand, the number of times i've needed to use their warranty support. And the things last for YEARS. I've replaced the battery in my 3 at home (2 on computer equipment and 1 on the TV) over the years. They just keep trucking along. Good hardware...something that's sometimes hard to fine here these days.

SoonerDave
07-24-2013, 07:29 AM
Okay, I'm ignorant on this thread. What is APC?

They were originally created/founded under the name of American Power Conversion corporation, and I think under their current ownership they've just become known as "APC." They are a very present manufacturer of all manner of battery back-up and surge protection equipment for electronics.

SoonerDave
07-24-2013, 07:35 AM
I say this from experience in calling in for warranty service on them over 10 years of use with APC small battery backups at my office....hundreds of them. Fortunate for me, wheni was first told about the "acts of god" thing, i hadn't yet given the serial number of the device so i just hung up, and called back with an altered story. I had originally called because after a storm, one device had failed and went Red with a beep = bad battery. It was only a month old, so the storm definitely killed it. When i called back in, i just said, "it's not working right. red light and beeping"...just failed to mention the storm.

Personally, i feel like they should have been responsible for it. Especially given how many we own....come on. On the same hand, i can count on 1 hand, the number of times i've needed to use their warranty support. And the things last for YEARS. I've replaced the battery in my 3 at home (2 on computer equipment and 1 on the TV) over the years. They just keep trucking along. Good hardware...something that's sometimes hard to fine here these days.

Bomber,

Keep in mind we're talking about a couple of different things - the warranty on the UPS device itself, and then the warranty or "insurance" offered on the connected equipment. APC (and other manufacturers) offer extended coverage against transients on the power network, and the discussion here has been at what point they decline to pay for damage related to surges arising from things like lightning strikes, which very typically fall under "force majeure" (Acts of God) exclusion clauses.

I suspect that if someone has been paid arising from a storm-related hit, that such a payment was a goodwill payment rather than an explicit warranty coverage issue. A deviation due to a transient is a far different thing from a voltage spike arising from a lightning strike.

Jim Kyle
07-24-2013, 08:18 AM
Bomber,

Keep in mind we're talking about a couple of different things - the warranty on the UPS device itself, and then the warranty or "insurance" offered on the connected equipment. APC (and other manufacturers) offer extended coverage against transients on the power network, and the discussion here has been at what point they decline to pay for damage related to surges arising from things like lightning strikes, which very typically fall under "force majeure" (Acts of God) exclusion clauses.

I suspect that if someone has been paid arising from a storm-related hit, that such a payment was a goodwill payment rather than an explicit warranty coverage issue. A deviation due to a transient is a far different thing from a voltage spike arising from a lightning strike.Note, also, that their coverage for surge suppressors is very different from that offered for their UPSes. Bomber's experience was with UPSes (and I agree with his endorsment of these products; I'm running three of them here right now) and I suspect that C.T. was referring to their surge suppressors. The clip I quoted above was for surge suppressors; the one cited by Bomber was for a UPS.

However, I suspect that the surge suppressors are used by many more folk than are the UPS lines. Most people are concerned about the possibility of lightning strikes and aren't even aware of the usefulness of battery backup systems in preventing power-glitch problems. And most, unless they've experienced it personally, are blissfully unaware of the huge amounts of power in even the tiniest lightning bolt!

SoonerDave
07-24-2013, 09:46 AM
Most people are concerned about the possibility of lightning strikes and aren't even aware of the usefulness of battery backup systems in preventing power-glitch problems. And most, unless they've experienced it personally, are blissfully unaware of the huge amounts of power in even the tiniest lightning bolt!

Absolutely.

One of the things that is (or should) become an increasingly important aspect of new home design considerations is whole home grounding. I've read some rather interesting (and, at times, rather intense) discussion on some engineering forums about the advent of power-sensitive microelectronics should increase the attention given to comprehensive home grounding design. The whole discussion about the (in)ability of a surge suppressor to even begin to handle a lightning strike tends to work backwards to the idea that if a home is properly grounded, a lightning strike should never really make it that far into the house in the first place, obviating the need for a surge suppressor. Such discussions are usually supplanted by the strong suggestion that new homes should also include some kind of power conditioner - again, all things we never thought of thirty or forty years ago, because we didn't have houses full of electronics that might be reduced to doorstops given the right kind of electrical line fluctuation.

As an adjunct to the APC discussion, the wordsmithing on their warranty language was not intended as any kind of slight on the company - I've used APC UPS products and have no problem with them. In fact, I'm pretty close to picking up (at least) one of their newer units for my office, as I just hadn't replaced the one I had in there that died quite some time ago...

Jim Kyle
07-24-2013, 10:19 AM
While I agree that proper whole home grounding is important, I don't think it's really practical to try to ground a whole home adequately to take the power of a direct hit and have any electronics inside survive. Many years ago, back in the days of 1200-baud modems, I had the on-off-hook relay contacts in my modem welded together in the off-hook position by a ground strike that was at least a quarter of a mile away from my home, but which put enough of a power surge into the phone wiring to weld that relay in one position. It did no other damage to the modem, and I continued using it until 14,400-baud units became available, but it made a significant impression on me. I have no idea whether a proper surge suppressor would have prevented the damage or not, but in those days they weren't available like they are today...

A close friend did take a direct hit on his ham radio tower once, and the power travelled down the outside of his coax feed line, jumped through open air from there to the house wiring, and incinerated his computer system as well as his radio equipment. I've been lucky in never taking a direct strike, but I did see a huge cottonwood tree about 150 feet from my back porch get split lengthwise by a relatively minor bolt a half-dozen years ago. It gives one a lot of respect for lightning, to see its aftermath.

ctchandler
07-24-2013, 11:41 AM
I committed to calling APC but at this point it doesn't seem to be necessary with all the research and comments since. I'm happy with APC's products and will continue to use them.
C. T.

bluedogok
07-24-2013, 10:06 PM
While I agree that proper whole home grounding is important, I don't think it's really practical to try to ground a whole home adequately to take the power of a direct hit and have any electronics inside survive. Many years ago, back in the days of 1200-baud modems, I had the on-off-hook relay contacts in my modem welded together in the off-hook position by a ground strike that was at least a quarter of a mile away from my home, but which put enough of a power surge into the phone wiring to weld that relay in one position. It did no other damage to the modem, and I continued using it until 14,400-baud units became available, but it made a significant impression on me. I have no idea whether a proper surge suppressor would have prevented the damage or not, but in those days they weren't available like they are today...

A close friend did take a direct hit on his ham radio tower once, and the power travelled down the outside of his coax feed line, jumped through open air from there to the house wiring, and incinerated his computer system as well as his radio equipment. I've been lucky in never taking a direct strike, but I did see a huge cottonwood tree about 150 feet from my back porch get split lengthwise by a relatively minor bolt a half-dozen years ago. It gives one a lot of respect for lightning, to see its aftermath.
We took a direct hit one night at Benham, fried a board (literally) in one of our Computervision CADDS/4X servers (Sun based server, this was in 1989). After that hit to a $200,000 server they decided to invest in a UPS, we had one of the UPS units as large as a small car installed and had them at all the desktop boxes which were about $40,000 a station at that time....which was why we had a night shift as well.

bombermwc
07-25-2013, 06:36 AM
And that's why i always tell people, unless you're willing to toss it in the trash after a surge, then you need to use a surge protector. Am i going to plug my coffee pot into one? Nah. But probably anything that's more than $50-60 or so because that $13 investment in the surge protector can make a big difference.

Unfortunately, our company has a few homebase people that were bit by the bug. The company owned equipment used our surgr protection gear and was saved. Everything else in their house....fried. One lady even had it happen twice. You'd think she would have learned after the first time. Very sweet lady, but apparently not the sharpest knife in the drawer.

ctchandler
07-25-2013, 07:16 AM
Bombermwc,
I have my coffee pot plugged into an APC. Of course it's not a cheap unit. I have at least one surge protector in each room and more than one in my family room along with my uninterruptible power supply units. By the way, my APC units were quite a bit more than $13. I think I have paid about $40 each. I don't know why the difference, but I am loyal to the brand I use, so I'm not sure it's any better than a cheaper one.
C. T.

Am i going to plug my coffee pot into one? Nah. But probably anything that's more than $50-60 or so because that $13 investment in the surge protector can make a big difference.

SoonerDave
07-25-2013, 09:25 AM
Bombermwc,
I have my coffee pot plugged into an APC. Of course it's not a cheap unit. I have at least one surge protector in each room and more than one in my family room along with my uninterruptible power supply units. By the way, my APC units were quite a bit more than $13. I think I have paid about $40 each. I don't know why the difference, but I am loyal to the brand I use, so I'm not sure it's any better than a cheaper one.
C. T.

I don't have a link handy, but I did see a video once that illustrated the fact that there is a distinct difference in the $10-range surge suppressors versus the $40 ones. As I recall, the cheaper ones are made in such a way that the disconnect across the switch can, itself, fuse, if a transient comes through, and can (in extreme cases) actually cause the suppresor to heat rapidly or even ignite. The better ones are constructed differently with better quality switch, but the components and construction are correspondingly more expensive.

If I can find that or a comparable link, I"ll post it, as I don't remember the details. Just know that the extreme end of the spectrum of cheap surge suppressors can almost be dangerous to use.

JayhawkTransplant
07-25-2013, 10:49 AM
This is great info, guys. So far, I have lost my modem, router, and microwave from the surges, so I will definitely be buying more surge protectors soon.

BBatesokc
07-25-2013, 01:48 PM
Sam's (at least the one in MWC) has an APC surge protector with battery backup (smaller unit) marked down to around $50 from $60 something.

I use their larger $150 dollar unit on my computers and office equipment and those smaller ones on my TV's, etc.

bluedogok
07-25-2013, 08:29 PM
Sam's (at least the one in MWC) has an APC surge protector with battery backup (smaller unit) marked down to around $50 from $60 something.

I use their larger $150 dollar unit on my computers and office equipment and those smaller ones on my TV's, etc.
I bought a bunch of those units years ago when they were around 35.00

Servicetech571
07-26-2013, 08:31 PM
Hi guys,

My neighborhood has been experiencing upwards of 5 power outages per day for the past few weeks. Dozens of us have reported this to OG&E, and when one neighbor actually talked to a human there earlier in the week, they said they would send someone out to assess the problem.

This morning, the electricity has been going out more than once a minute. My brand new air handler, less than 2 months old, started making loud noises that made me think that the power surges had fried it, so I completely turned off power to everything in my house.

So, I have a few questions:

1) Is this happening to those of you who live outside of the 23rd and May area?
2) If these power surges did indeed fry my compressor, do I have any recourse with OG&E? I have personally reported power surges to them for the last 4 days.

Install a time delay on your system so it won't restart for 5 minutes after loosing power. If you have a digital thermostat powered by the system common wire (not AA power) this feature is normally built into the thermostat. BTW the free OG&E Smarthours thermostats have this feature built in.

SoonerDave
07-27-2013, 12:54 PM
I'm by no means an electrical expert or electrician, but this thread prompted me to do a bit of "catch-up" reading, and I came up with a few of notes on surge protectors that might foster a bit of discussion.

There's a pretty good case to be offered on what's called "whole house protectors" that connect directly to your main power panel. These protectors tie directly to an earthed ground and can prevent big shocks from ever getting inside the house wiring through the AC lines, and are rated for upwards of 40-50kA. These devices kinda in the vein of what large computer centers and businesses do for lightning protection - just keep the zap from ever getting into the building. I've read about devices for as little as $50 that I think would be worth considering, although I must admit I have not undertaken to get one myself. They are somewhat DIY if you're comfortable working with electricity, but the safest route is to contact an electrician to ensure its installed correctly. An example of such a beast is here, (http://www.homedepot.com/p/Leviton-120-240-Volt-Residential-Whole-House-Surge-Protector-R00-51110-SRG/202993881#.UfQId41QF8E) but there are others. Such a device protects against AC line surges coming from the inbound power panel. Has anyone ever used a device like this? Any feedback? It looks very appealing to me as a good possible choice.

Whole house protectors don't guard against the other kinds of surges, which is where point-of use surge protectors come into play. Desktop "suppressors" (which really don't suppress, they redirect) work by detecting overvoltage conditions (ideally at no higher than 330V) and routing any such input back down through the safety ground on the outlet plug. Now, most ground plugs are not immediately earth-grounded, but are tied off to the neutral wire at the breaker box and then to ground. The kicker is that some other potentially earth-grounded items, such as satellite dishes, can afford the possibility for what's called a "ground bridge" that could create a shorter path to ground (eg through the coax) that then goes right through any connected devices. In that vein, a surge protector can actually increase the risk of surge-related damage that doesn't come in over your AC lines. Someone better versed in the details could probably explain it better than I did, but at least the idea's there. Its just that electricity is going to find a path to ground somehow, even if its not the ground you think it is :) Keep in mind that as the physical distance from the safety ground to "earth" ground increases, so does wire impedance, meaning that if there's a shorter (or less resistive) path to ground, that's what electricity will take.

Also, most (but not all) suppressors employ a gadget called an MOV (Metal-Oxide Varistor) that performs the essential shunting function. These little gadgets have a finite capability to redirect electricity - each overvoltage it detects reduces its lifespan. After a time, and enough overvoltages, the MOV no longer operates as a shunt, and the suppressor strip is no longer protecting - its just a straight power strip. Most higher-quality suppressor strips have separate indicators for ground and protection, but the fact that the "Protection" light is on doesn't really tell you how much of a hit the thing can take. It's generally a good idea to replace any MOV-based surge suppressor that's been in service for a few years.

Last, older MOV-based suppressor strips are at risk for overheating and causing a fire as the epoxy coating on the MOV overheats and deteriorates. A change the specifications used by UL in certification of theses devices required the use of what amounts to a "thermal fuse" that essentially shuts the thing down if it gets too hot. The key here is to avoid using any really old suppressor strips for this reason.

Jim Kyle
07-27-2013, 02:47 PM
Someone better versed in the details could probably explain it better than I did, but at least the idea's there. Its just that electricity is going to find a path to ground somehow, even if its not the ground you think it is :) Keep in mind that as the physical distance from the safety ground to "earth" ground increases, so does wire impedance, meaning that if there's a shorter (or less resistive) path to ground, that's what electricity will take.Standard 110-volt (more accurately 117 volts and often called 120) distribution in the USA comes from the power mains through a stepdown transformer that provides 220-240 VAC across its full secondary, but is center-tapped to allow two different circuits into the house. That's why older drops from the "pole pig" transformers had three wires to the house instead of just two. This center tap is connected to ground at the power pole, so that both outside wires are at a potential of 110-120 volts with respect to ground. Its wire, called the "neutral" by electricians, should also be connected to ground at the breaker panel, to protect the house.

This grounding of the neutral wire is why ungrounded appliances can be so dangerous, since metallic plumbing is almost always connected to ground (simply by being buried in it), and a breakdown of insulation in an appliance can made its metallic case take on full line potential if the case isn't grounded. If it is, then the breakdown usually blows a fuse or trips a breaker since it appears as a dead short across the line.
Also, most (but not all) suppressors employ a gadget called an MOV (Metal-Oxide Varistor) that performs the essential shunting function. These little gadgets have a finite capability to redirect electricity - each overvoltage it detects reduces its lifespan. After a time, and enough overvoltages, the MOV no longer operates as a shunt, and the suppressor strip is no longer protecting - its just a straight power strip. Most higher-quality suppressor strips have separate indicators for ground and protection, but the fact that the "Protection" light is on doesn't really tell you how much of a hit the thing can take. It's generally a good idea to replace any MOV-based surge suppressor that's been in service for a few years.The MOV is effectively simply a fuse that instead of opening the circuit, closes it when the voltage rises above its trigger point. "Varistor" is a term coined from "variable resistor" to indicate that the device's resistance varies according to some operating condition; in the MOV, that condition is the voltage applied across it. In the simplest form of surge suppressor (now long obsolete) the MOV was simply connected between the hot and neutral power lines, inside the device. At normal voltage levels, its resistance was so great that it had no significant effect at all. However when voltage rose high enough (usually more than triple the normal value) the resistance dropped low enough to effectively short out the circuit and effectively prevent the surge or spike from getting through to the connected equipment.

If the overvoltage lasted long enough, or was high enough, the poor MOV would simply melt under the load; ideally the main fuse or breaker would trip before this happened, but the tiny MOVs usually burned out long before a fuse or breaker could react. Thus the overvoltage would have nothing keeping it from getting to the equipment. That's why such suppressors usually included a warning light that would glow green so long as they were in good condition, but turn red if the suppressor was damaged. This usually happened the very first time the suppressor did its job!

Today's suppressors are, I suspect, much more sophisticated that what I've described. The best-of-breed varieties have additional sensors in them to detect faulty house wiring and such things. However the MOV is still the active element, and suppressors that have been hit once by a spike or surge ought to be replaced ASAP.

Incidentally, any structure that's subject to a building code, or is insured against fire, should never have any work on its power lines done as DIY -- virtually all codes and insurance policies require that the electrical systems be maintained only by licensed electricians. I'm not one, although I've dealt with electronics for more than 50 years now (and written a number of books on the subject). While in the past I've done some of my own wiring, I'd not consider it any more -- for legal reasons if nothing else.

Servicetech571
07-28-2013, 09:49 AM
That's why older drops from the "pole pig" transformers had three wires to the house instead of just two. This center tap is connected to ground at the power pole, so that both outside wires are at a potential of 110-120 volts with respect to ground. Its wire, called the "neutral" by electricians, should also be connected to ground at the breaker panel, to protect the house.
Actually ALL houses have 3 conductors going from pole to house, sometimes the extra conductor is insulated or twisted with the 2 hot conductors. Grounds from outlets, ground to grounding rod and Neutrals for outlets/power pole are all connected together in the breaker box. The Nuetral bus bar and grounding bar are connected together in the breaker box. With an ohmeter you can measure ground ot neutral of any outlet and it should read less than 5 ohms (the resistance of the wire back to the breaker box). If itreads higher than you have a bad ground or bad neutral.
4200


This grounding of the neutral wire is why ungrounded appliances can be so dangerous, since metallic plumbing is almost always connected to ground (simply by being buried in it), and a breakdown of insulation in an appliance can made its metallic case take on full line potential if the case isn't grounded. If it is, then the breakdown usually blows a fuse or trips a breaker since it appears as a dead short across the line.
The water pipe has nothing to do with why an ungrounded appliance shocks. Water pipes are typically NOT metal on homes built in the past 30 years, although older homes did use the water pipe as the "groundign rod". The ungrounded appliance simply has a power line shorted to a metal cabinet.

Jim Kyle
07-28-2013, 10:07 AM
The water pipe has nothing to do with why an ungrounded appliance shocks. Water pipes are typically NOT metal on homes built in the past 30 years, although older homes did use the water pipe as the "groundign rod". The ungrounded appliance simply has a power line shorted to a metal cabinet.But the water itself does offer a conductive path to ground, and the danger to which I referred often strikes when a person touches the hot cabinet and the water faucet at the same time.

My current residence has a few feet of non-metallic pipe connecting the water softener to the main house pipe network, but I'd bet there is still a path to ground from the kitchen faucet or any bathroom fixture. The GFCI offers pretty good protection, though; it sometimes trips when a hair dryer and other appliances are in use at the same time!

My previous residence had severe grounding faults; when built in the late 1920s, it used knob and tube wiring. A previous owner had replaced most of that (the detached garage still had knob and tube when I moved in, in 1967) but did not use 3-conductor Romex; it was still 2-conductor, with not a single 3-prong outlet in the place and no protective grounds. The family from whom I bought the place had added a (not very well built) second story, so I suspect that they were DIY folk and did the rewiring themselves.

I would get a slight tingle whenever I touched the refrigerator and the range hood at the same time; never did determine which had the problem, and since it was barely enough current to feel, it could have been simply inductive leakage and a ground loop. When I remodelled the kitchen, I had Harrison Electric handle proper grounding and put 3-prong outlets in the kitchen area.

Servicetech571
07-28-2013, 11:26 AM
Crappy electrical remodel/work is all too common. I saw a house where they ran the Dryer and Stove off the same 50A wire/breaker, aluminum wire at that...
Was a "flip house" and those seem to be the worst about fixing mechanical systems. Make it look pretty, leave all the old HVAC/Plumbing/Electrical.
IMHO flippers should be held to the same standard as contractors when it comes to remodel work, and should require permits/inspections.
First time home buyers are normally the ones who don't spot the mechanical system problems until it's too late.

Mel
07-28-2013, 09:56 PM
The Sam's APC battery/surge protectors are good. It pays to protect your pricey electronics. Money well spent. My computer is protected by a APC product. two external hard drives, a .357 and a attack ferret.