OG&E Power Surges and Outages

[ctchandler]

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]

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]

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]

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]

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]

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]

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, 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]

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]

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.

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]

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]

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]

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.