Fixing Static Electricity Issues: Tips from an Electrician

AI Thread Summary
Static electricity is causing repeated damage to garage door openers located in a pole barn, particularly after electrical storms. The barn is grounded, but the effectiveness of this grounding is in question, as well as the potential for static charge accumulation. Suggestions include installing a lightning rod to dissipate static electricity and ensure proper grounding of the barn's wiring. Concerns about attracting lightning with a lightning rod are addressed, emphasizing that it can help prevent static discharge. Overall, improving grounding and considering external static dissipation methods are critical to protecting the electronics from damage.
WHS SHOCKED
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I have a problem that is costing me lots of $'s. I built a pole barn seven years ago that is about 50 feet from my house and garage. I am on my third garage door opener due to logic boards being destroyed by static electricity. I have had a second electrician check out my wiring and he says he can't find anything wrong. We did add a ground for the pole barn where before it was grounded through the house where the power originates. I have a surge protector on the garage door opener itself. These are Chamberlain garage door openers sold by Sears. All have been the same model since I had to add a extension for the rail because of the oversize door. It's the only model that Sears sells that will use an extension. I have been told by Sears / Chamberlain that static electricity is the problem and the logic boards are susceptible to static electricity. All of the problems have been after electrical storms. I have never had a direct hit to the barn or house. ( Knock on wood!)

I am trying to come up with a way to arrest the static electricity. My thought is if I ran some light wire around the top of the barn above the garage door opener and connected it to the direct ground wire that I had installed that this would be the best attraction for the static electricity. My concern is that I don't want to create an attraction for a direct lightning strike.

Before you give me your lofty answers let me tell you I know about as much about electricity as I know about quantum physics or women or ... well you get it, I'm an idiot about electric. So please explain to me like you would to let's say a Cocker Spaniel.

Thanks!

Bill
 
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Welcome to PF WHS SHOCKED.

What type of roof does your pole barn have? If it's a corrugated steel one, you could put up a lightning rod connected to it.
 
dlgoff said:
Welcome to PF WHS SHOCKED.

What type of roof does your pole barn have? If it's a corrugated steel one, you could put up a lightning rod connected to it.

It has an asphalt shingle roof and vinyl siding. All wood framing.
 
Well, my parents house has a lightning rod on the composite shingle roof and the house has never "attracted" lightning. It has a steel cable leading to a ground rod.

If you do put up one, the ground must be very good (depends on soil condition and how well the ground rod contacts the earth).

433px-Lightning-rod-diagram.svg.png


http://en.wikipedia.org/wiki/Lightning_rod"
 
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Would a lightning rod on the outside of the barn arrest static electricity on the inside of the barn? There are no signs that the barn has ever been hit by lighting. Just static electricity caused by lighting?

Thanks for the reply.
 
The idea is, the static build-up on the building would be shunted to ground preventing discharge surges which may be what's killing your electronics. A lightning strike isn't necessary to get discharges. From the wiki link:

Diversion is a misnomer; no modern systems are claimed to divert anything, but rather to intercept the charge that terminates on a structure and carry it to the ground. The energy in a lightning strike is measured in joules. The reason that lightning does damage is that this energy is released in a matter of microseconds (typically 30 to 50 microseconds). If the same energy could be released slowly over a period of many seconds or minutes, the current flow would be in milliamperes or a few amperes at most. This is the intent of charge dissipation.
 
dlgoff said:
The idea is, the static build-up on the building would be shunted to ground preventing discharge surges which may be what's killing your electronics. A lightning strike isn't necessary to get discharges. From the wiki link:

Ok now. Please remember to explain like you would to a Cocker Spaniel.

Are you saying yes, a lightning rod would get rid of static electricity inside the barn? If this is correct then why wouldn't a wire inside the barn attached to my ground wire do the same thing?
 
Cocker Spaniel? Nope. :wink:

Yes. The charge build-up will accumulate on the building with the highest charge on the roof. So the lightning rod should discharge (equalize the charge with Earth over time) of the whole building. Check out this explanation of how the charge builds up. i.e. how positive and negative charge build-up.

http://hyperphysics.phy-astr.gsu.edu/hbase/electric/lightning.html

From this animation, you can see that you don't have to have a direct strike to [STRIKE]be[/STRIKE] have discharges that can cause electronic component damage.

Leaderlightnig.gif
 
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So why wouldn't my inside "do-it-myself" system work? Does the suppression have to be on the outside of the building roof?
 
  • #10
WHS SHOCKED said:
Does the suppression have to be on the outside of the building roof?

This would be best; where the charge density is largest.
 
  • #11
Would my system be better than nothing at all? Would it possibly create any more problems like attracting static electricity?
 
  • #12
Without seeing your system (which doesn't sound like it would do too much), it would be hard to tell. As far as "attracting" static electricity; probably not.

Why not just put up a simple/cheap rod on the highest point of the roof? You must consider the cost between installing a lightning rod/ w good ground and the cost of replacing the electronics.
 
  • #13
Well beside being an electrical idiot, I'm cheap!

But replacing Garage Door Openers isn't cheap either so I am going to have to do something. Are there systems for "do it yourselfers" out there? Or is this something that is best left to the pros?

Thanks for your indulgence with me. I appreciate it much.
 
  • #14
There are DIY lighting protection suppliers. For example (note: I'm not endorsing any particular supplier. I just googled.):

http://www.lightningrod.com/"
 
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  • #15
It's the only model that Sears sells that will use an extension. I have been told by Sears / Chamberlain that static electricity is the problem and the logic boards are susceptible to static electricity. All of the problems have been after electrical storms.

What does this mean? "extension"?? How does the wiring get from your house to the barn? Above ground or buried? Even buried cable can require lightning protection. Power and communications companies do that all the time on their underground and sometimes above ground cables.

If lightning caused the problem, "static electricity" is hardly the issue unless you mean
"lightning". Try talking with someone else at Chamberlain..you might get a different answer.

Exactly how was the barn wiring "grounded" at the barn. What wires were connected to ground? Is the wiring from the house to barn "grounded"...a three wire cable for 120 volts, with a bare wire??

Are you positive your house is properly grounded??

Was this inspected and approved? If not, find out how it was grounded and go down to you electrical inspectors office and ask how it should be done.

You should to talk with someone who is expert in (practical) grounding issues not a run of the mill electrician who likely does not understand all the issues.
 
  • #16
Naty1 said:
What does this mean? "extension"??

I'm fairly sure he means a mechanical extension of the door hanger.

All have been the same model since I had to add a extension for the rail because of the oversize door. It's the only model that Sears sells that will use an extension.
 
  • #17
Naty1 said:
What does this mean? "extension"??

Extension of the rail for an 8' door





How does the wiring get from your house to the barn? Above ground or buried?


Buried cable in conduit.





If lightning caused the problem, "static electricity" is hardly the issue unless you mean
"lightning".

I have been told that lightning strikes in the area will fry the logic board.


Exactly how was the barn wiring "grounded" at the barn. What wires were connected to ground? Is the wiring from the house to barn "grounded"...a three wire cable for 120 volts, with a bare wire??

There are 4 wires all the same.


Are you positive your house is properly grounded??


I haven't had any problems with anything else inside of the house. I even have an attached garage with the exact same model garage door opener that has worked fine for over ten years.




You should to talk with someone who is expert in (practical) grounding issues not a run of the mill electrician who likely does not understand all the issues.


That's why I'm here. I am looking for answers!

Thanks
 
  • #18
Is the circuit board inside a metal box?
Is the metal box connected to the green (or bare) wire that goes back to Earth somewhere, hopefully to panel in your house??

Take your voltmeter and check voltage from black wire to that green (or bare) wire
you should get 115 volts or whatever the electric co is delivering you that day
and you should read exactly same between black and white wires.
If not, something is not right in your wiring out to the opener..

next take your 75 ft extension cord .
Plug it into a good outlet in your house and carry the other end out next to your garage door opener.

Using your multimeter on lowest ohms scale,
read the ohms between your garage door opener frame and the round safety contact hole in your extension cord plug. You may have to insert a nail or something to get contact there.
If it's more than an ohm or so find and fix the bad connection.
Now you've verified that you have a decent Earth ground at your door opener -

is the circuit board protected from electric field ?
If it's inside a metal cover that's grounded (i prefer term "earthed"), that should do the job.
If the cover is plastic, well, get your pop-riveter and some aluminum flashing and give it a metal skin, and Earth that with a screw to the frame or a short ground wire to a nearby frame screw.

I once had a Sears water softener that was sensitive to the power surges that come in when lightning strikes power line. You said you had a surge protector on the opener - close to the opener i assume.
it is important that the surge protector have good connection to earth. Hence those first checks. Your wire to Earth should be about as large as the conductors,
and run directly without splices.
Lastly routing is important. The Earth wire should be run physically with the other two wires to make a threesome.
If it is not physically close to the other two wires you have a loop antenna.
The wires define the loop and the larger the loop's area the more effective it is at extracting energy from nearby lightning strokes. Google Biot-Savart.

Same applies to the black and white wires - be aware that if they are not run together and a loop exists, that is a setup for your kind of troubles.

just guessing, but it's always good to rule out the simple stuff.

Hmmmmm what about those wires that go out to the photocells looking acrossbottom of door for tiny feet?
Don't build a loop antenna around the door, run both wires together even though it might take some extra.

old jim
 
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  • #19
WHS SHOCKED said:
But replacing Garage Door Openers isn't cheap either so I am going to have to do something.
A direct lightning strike far down the street to AC wires is a direct lightning strike to every appliance in the house. Why are only some or no appliances damaged? A surge enters on one wire, does damage and stops? Of course not. That violates what everyone was taught in primary school science.

First and electric current must have an incoming and a completely different outgoing path. The electricity exists simultaneously everywhere in that path. Long later, something in that path is damaged - ie the garage door controller.

Again, the surge is incoming to everything. But only some things also have the outgoing path to earth. Those are the damaged appliances. This important concept taught in elementary school science is forgotten to create myths.

Static electricity can be so massive as to make the hairs on your arms or head stand on end. And that still must not cause any appliance damage. Protection already inside each household appliance is so robust as to make trivial static irrelevant.

Lightning rods only Earth static when myths are promoted. Either lightning uses something conductive to connect to Earth - ie wood. Or lightning is given a more conductive and therefore not destructive path to Earth - ie the wire and Earth ground wire that connects to a lightning rod. BTW, lightning rods do not do protection. Lightning rods only connect to what does protection; what absorbs hundreds of thousands of joules. That is Earth ground.

Earth ground explains why your garage door controller is damaged. For example, how many AC wires enter that garage? Two? Three? Four? If any wire does not connect direct to Earth before entering the garage, then the controller has zero protection. A best path to Earth is incoming on a 'hot' wire, through the controller, then out to Earth via the wooden garage. Why does lightning strike wooden church steeples? Wood is an electrical conductor.

Remember how damage happens. First, an incoming and another outgoing electric current path exists. Much later, electronics fail. That controller must be in a path from cloud to earth. Or it is not damaged. That explains what you must do to have no more damage.

You have at least one wire entering the garage without a short (ie 'less than 10 foot') connection to single point Earth ground. So that garage has no effective protectors. A protector adjacent to the controller (and too far from Earth ground) might even make damage easier. But again, protection begins when you first define the incoming and outgoing current path from cloud to earth. A surge seeking Earth (destructively) exists even when lightning strikes far down the street.
 
  • #20
So westom since I know nothing about electricity as I explained in my initial post, and therefore mostly what I read was blah blah, blah blah blah, blah, are lighting rods a good idea or not?

No offense intended.
 
  • #21
I think the lightning rods are a good idea, but I don't think it will solve your problem. I would guess your wiring is fine if you had it done professionally, you don't have any other issues, and you have had it inspected.

Is your opener plugged into a standard outlet mounted on the ceiling?

Is the logic board mounted on the wall, or is it in the lift assembly on the ceiling?

You said this is your 3rd opener; so you have replaced the complete opener assembly (the motor on the ceiling as well as the wall units)?
 
  • #22
gtacs said:
I think the lightning rods are a good idea, but I don't think it will solve your problem. I would guess your wiring is fine if you had it done professionally, you don't have any other issues, and you have had it inspected.

Is your opener plugged into a standard outlet mounted on the ceiling?

Is the logic board mounted on the wall, or is it in the lift assembly on the ceiling?

You said this is your 3rd opener; so you have replaced the complete opener assembly (the motor on the ceiling as well as the wall units)?

Opener is pluged into a standard outlet at the opener. The logic board in inside the opener itself. I am on the third opener. It's cheaper to replace the whole opener than replace the logic board. I have had at least two logic boards replaced under warranty. So actually this is about the fifth or sixth time I have had a logic board fail.

I have been told by Sears / Chamberlain that the surge protector they sell will take care of the problem. I have bought one of theirs to install after I get the thing fixed. Their surge protector is different in that it protects the electric eye control wires that go to the logic board and also the control panel where the door button is located. The electric eye wires go directly into the surge protector and then on to the opener. The control panel wires go to the surge protector and then on to the opener. And then there is the regular outlet for power for the unit itself. It makes sense that it would work if the static it reaching the logic board from the wires from the control panel or the electric eyes.

We'll see!

Thanks!
 
  • #23
Sounds like you got it! Good Luck!
 
  • #24
gtacs said:
Sounds like you got it! Good Luck!

Would you go ahead with lighting rods anyways?
 
  • #25
WHS SHOCKED said:
So westom since I know nothing about electricity as I explained in my initial post, and therefore mostly what I read was blah blah, blah blah blah, blah, are lighting rods a good idea or not?
Lightning is a connection from cloud to earthborne charges. So that lightning does not make that connection through a structure (ie wood), then Franklin connected that electric current to Earth via a better conductor: a wire that connects the rod to an Earth ground. How often does that problem exist in your venue? One needs at least a decade of history to begin to make that decision.

So that lightning does not make that connection through appliances, homeowners connect that electric current to Earth via a low impedance conductor: either a hardwire or a 'whole house' protector. How often does that problem exist? More often because a conductor network highest on poles down the street connects lightning directly to all appliances. This occurs maybe once every seven years. A number that varies with each venue depending on factors including geology, how utility wires connect to the building, and other environmental factors.

Are you protecting the structure or appliances? Two solutions for two different problems.

Static electricity: if typically destructive, then 18,000 or 20,000 volts generated by a human would routinely destroy computer keyboards, iPads, and mobile radios. Appreciate the threat. A long wire radio antenna intended to maximize an E-M field might have many thousands of volts. So an NE-2 (neon glow lamp also found in lighted wall switches) might connect to that antenna's lead. Single digit milliamps conducted by that glow lamp cause thousands of volts to be reduced to tens. The massive voltage created by nearby lightning strikes or static electric discharges are made irrelevant by things trivial such as a neon glow lamp. Many will cite that thousands of volts. But forget to mention how trivial protection is from such voltages.

Start by addressing what you want to solve (current through a structure or current through appliances). Appreciate how other anomalies (ie static electric discharges and EM induced voltages) are so easily averted.

Nothing stops or absorbs surges. A protector adjacent to electronics will somehow do just that because a salesman said so? Protection always means diverting/bonding/connecting/conducting a surge current outside a building, away from electronics, and harmlessly to earth. Effective protection means a lightning rod or 'whole house' protector does that earthing on a path that does not use a building and does not use appliances.

If every wire entering that building does not first connect to single point Earth ground, then all protection is compromised. How many AC wires connect a garage to the house? Is each wire earthed? Effective protection means no surge current is anywhere inside that garage. Obviously, you have a wiring fault that all but invites surge currents to seek Earth ground destructively via the opener. Any 'not earthed' AC wire is one example of why that destructive current exists. And why protectors adjacent to the opener do too little too late.
 
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  • #26
westom,

I'm sure you know what you are talking about and I am sure many on this forum will be as physically excited reading your post as I get reading Dear Penthouse. However, all I got from your post was blah blah, blah blah blah, effective protection means a lightning rod or 'whole house' protector do that earthing.

I think you are agreeing that lightning rods would be a good idea for me.

No disrespect to you or anyone else intended. Just trying to make light of my ignorance of electricity.
 
  • #27
WHS SHOCKED said:
Just trying to make light of my ignorance of electricity.
Is that light as fleeting as lightning?

If you understand something in a first reading, then you already knew most of that. Did not learn something new. If that post contains new concepts, then at least three rereads are required to comprehend it.

The post contained many questions. None are rhetorical. In one of the rereads, provide answers to every question so that many solutions can be narrowed down to the few relevant ones.

If a surge current is given a path to enter the garage, then the resulting damage is traceable to human failure. Best learning comes from mistakes. For example, one question asked how many wires connect house to garage. An answer was required. How many of those wires connect to earth? Again, an answer is essential for a solution. Did lightning connect to that closer by conducting through "2 by 4's"? Then a lightning rod is needed. Did lightning not conduct through wood? Then a problem solved by a lightning rod does not exist.

What was a destructive current path from a cloud to earth? Only effective solutions will also answer that question. Any solution that does not answer is probably wasted money. Your every solution starts by finding the current path into the garage. And how that current then goes to earth. To understand a paragraph like this, to me, always meant rereading it multiple times.

Your every solution starts by learning how lightning connected to Earth via the controller. One place to begin is by answering every posted question even if you do not have an answer.

I think you are agreeing that lightning rods would be a good idea for me.
First you must say if lightning connected to the controller via 2x4 wood.
 
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  • #28
I'd wager the problem is from those "electronic eye" wires and a surge suppressor that protects them will cure it. That Sears offers one says you are not the first to have trouble.
[Good ol' Sears. Try getting support at Walmart...]
The eyes need to go into a logic input for the microcomputer and are a likely "soft spot" in the electronic design.

Also is the door metal?
If so, it's hanging out there like a giant flat plate antenna.
You might examine your car hood for an example of "how to" -- there is some electrical connection from hood to car chassis when closed. Sometimes a flexible cable, sometimes a flat spring with teeth that engage the sheet metal when hood is closed.
Purpose of that connection is to shield your radio antenna from the sparkplug wires. A shield does no good if it's not "grounded" and the hinges often have a nylon anti-friction bushing that unfortunately insulates too. .
Look closely at the garage door to see if the factory made provision to ground it to the track when closed.

What part of the world do you live in? I came from S Florida, the world's lightning capital.

You said there's four wires going to garage - that sounds good probably two black hots, a white neutral and a green or bare safety ground.



old jim
 
  • #29
jim hardy said:
I'd wager the problem is from those "electronic eye" wires and a surge suppressor that protects them will cure it. That Sears offers one says you are not the first to have trouble.
[Good ol' Sears. Try getting support at Walmart...]
The eyes need to go into a logic input for the microcomputer and are a likely "soft spot" in the electronic design.

Also is the door metal?
If so, it's hanging out there like a giant flat plate antenna.
You might examine your car hood for an example of "how to" -- there is some electrical connection from hood to car chassis when closed. Sometimes a flexible cable, sometimes a flat spring with teeth that engage the sheet metal when hood is closed.
Purpose of that connection is to shield your radio antenna from the sparkplug wires. A shield does no good if it's not "grounded" and the hinges often have a nylon anti-friction bushing that unfortunately insulates too. .
Look closely at the garage door to see if the factory made provision to ground it to the track when closed.

What part of the world do you live in? I came from S Florida, the world's lightning capital.

You said there's four wires going to garage - that sounds good probably two black hots, a white neutral and a green or bare safety ground.



old jim

Actually I have the electric eyes mounted up near the opener itself to more or less by-pass this safety. So there is only a few feet of wire for the electric eyes. However, the wires for the control panel where the button is to open & close the door are probably about 20 - 30 feet long. I'm guessing since it's the longest run it's coming from there. Either way though, the surge protector should help, I'm hoping anyways. The people from Chamberlain / Sears seemed to be well aware of the problem.

The door is metal clad so yes I can see where I have a huge antenna looking for static. I wonder if I grounded the door track if that would offer some protection? I don't want to attract lightning though and I wonder if grounding the door if it would?

I have four wires going to the barn. Two hot, neutral and a ground. All are coated wire in conduit.

I'm in central Ohio. We get some dandy storms sometimes. The funny thing is the house is just 50 feet from the pole barn and I have never had any trouble with anything in the house. We have a lot of electronics and nothing at all. I even have the exact same garage door opener in my atttached garage. However, the barn does sit higher by a few feet than the house.

Thanks for the reply and the plain English.
 
  • #30
" However, the wires for the control panel where the button is to open & close the door are probably about 20 - 30 feet long. "

look around that panel for anything unusual - a nicked wire touching metal, or a mounting screw that's come loose and laying against a PC board. Hand over hand that thirty foot wire looking for nicks or where it lays on something sharp. Probably won't find anything but if you do it's a jackpot.

Grounding the door track ought to ground the door through the bearings in rollers.
But only change one thing at a time...
I'd probably run a piece of bell wire from each track to frame
that'll give you a drain for static and nearby induced charge.

lightning strokes are interesting

typical one is only a few amperes
but they get huge
30 kiloamps is a whopper and not really uncommon
biggest I've seen referenced is in 200kiloamp range
when those big'uns get into an electric power system stuff gets blown up

study the wires on poles in your area.
In S Florida the electric company puts the bare and grounded neutral wire along the top of the poles so it'll act as a lightning rod and keep lightning out of the three phase conductors below.
Here in Arkansas i see the neutral run BELOW the phase wires.
You can tell the neutral - its insulators are the smallest, if it is insulated at all.

Just curious.

I'm still thinking about the layout of your stuff.
Is your garage between the house and power pole?
Inspect the bare copper wire down side of your utility pole. It is IMPORTANT that wire be intact - sometimes kids will cut a piece out of it for some project and power company won't know until they are on the pole for some reason.
And look at the grounding rod near your meter box, everything inplace and tight not oozing green corrosion?

old jim
 
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  • #31
WHS SHOCKED said:
Would you go ahead with lighting rods anyways?
I would wait to see if the surge protector is going to work. You may have to wait until you get a couple of those thunder storms.
 
  • #32
jim hardy said:
" However, the wires for the control panel where the button is to open & close the door are probably about 20 - 30 feet long. "

look around that panel for anything unusual - a nicked wire touching metal, or a mounting screw that's come loose and laying against a PC board. Hand over hand that thirty foot wire looking for nicks or where it lays on something sharp. Probably won't find anything but if you do it's a jackpot.

Grounding the door track ought to ground the door through the bearings in rollers.
But only change one thing at a time...
I'd probably run a piece of bell wire from each track to frame
that'll give you a drain for static and nearby induced charge.

lightning strokes are interesting

typical one is only a few amperes
but they get huge
30 kiloamps is a whopper and not really uncommon
biggest I've seen referenced is in 200kiloamp range
when those big'uns get into an electric power system stuff gets blown up

study the wires on poles in your area.
In S Florida the electric company puts the bare and grounded neutral wire along the top of the poles so it'll act as a lightning rod and keep lightning out of the three phase conductors below.
Here in Arkansas i see the neutral run BELOW the phase wires.
You can tell the neutral - its insulators are the smallest, if it is insulated at all.

Just curious.

I'm still thinking about the layout of your stuff.
Is your garage between the house and power pole?
Inspect the bare copper wire down side of your utility pole. It is IMPORTANT that wire be intact - sometimes kids will cut a piece out of it for some project and power company won't know until they are on the pole for some reason.
And look at the grounding rod near your meter box, everything inplace and tight not oozing green corrosion?

old jim

I'll go over the wire to the panel to make sure.

I don't understand the bell wire from track to frame comment. Can you explain what you mean?

The power pole is seven hundred feet away. From there it is undergraound. I had the electric company out to check the above ground transformer which is right next to the barn. It all checked out and the ground on the transformer was good.

There is a ground rod at the meter and seems to be ok.

Thanks
 
  • #33
dlgoff said:
I would wait to see if the surge protector is going to work. You may have to wait until you get a couple of those thunder storms.



Thanks for your answers. Unfortunately, if the past is any indicator of the future it will be until next August before I will know. All three openers have been bought in August and all around the third week of August. Perhaps there was someone that was killed in the area of my barn in August?

We do have some pretty good storms in late summer but we have some dandys in the spring too.

At this point I could believe anything!

Thanks!
 
  • #34
"I don't understand the bell wire from track to frame comment. Can you explain what you mean? "

Sorry, i was just seconding your opinion about grounding the tracks.

"Bell wire " is that cheap solid wire usually 20 or 22 gage that you get in hardware stores. It's used for dooorbells.

A piece of that from each track to opener frame should provide a minimal ground.
You could use the bare wire from some leftover Romex, or whatever you have.
Just route it so it won't get tangled in the mechanism - i don't know if yours is shaft with spring wound around it or what.

hmmmm... several hundred feet between pole and transformer, transformer adjacent garage...
actually your nearness to transformer sounds like a good thing.

You said you added a ground rod at barn entrance...

how far fron transformer ground is it? no ideas here, just musing here.
I really think you'll be good with the protector from Sears/Chaimberlin.

old jim
 
  • #35
jim hardy said:
"I don't understand the bell wire from track to frame comment. Can you explain what you mean? "

Sorry, i was just seconding your opinion about grounding the tracks.

"Bell wire " is that cheap solid wire usually 20 or 22 gage that you get in hardware stores. It's used for dooorbells.

A piece of that from each track to opener frame should provide a minimal ground.
You could use the bare wire from some leftover Romex, or whatever you have.
Just route it so it won't get tangled in the mechanism - i don't know if yours is shaft with spring wound around it or what.

hmmmm... several hundred feet between pole and transformer, transformer adjacent garage...
actually your nearness to transformer sounds like a good thing.

You said you added a ground rod at barn entrance...

how far fron transformer ground is it? no ideas here, just musing here.
I really think you'll be good with the protector from Sears/Chaimberlin.

old jim

Got you on the bell wire. I was actually thinking of grounding the tracks to the Earth ground next to the barn. Any ideas there?

My Earth ground to the transformer would be about 30 feet.
 
  • #36
WHS SHOCKED said:
... if the past is any indicator of the future it will be until next August before I will know.
Dang. I hope I don't have to wait that long here in Kansas. We need the rain; let is storm. :approve:
 
  • #37
"Got you on the bell wire. I was actually thinking of grounding the tracks to the Earth ground next to the barn. Any ideas there?"

i think that'd be fine.
 
  • #38
WHS SHOCKED said:
Got you on the bell wire. I was actually thinking of grounding the tracks to the Earth ground next to the barn.
Will only make damage easier as explained in previous posts that also said why.

Stop wasting time with myths about damage due to E-M fields. That was also explained with an example of how trivial that surge is. E-M fields even from lightning only feet away do not harm anything. Are made completely irrelevant by an NE-2 neon glow lamp. Please read that post multiple times to appreciate how silly that E-M field myth is.

Another example. Lightning struck the building lighting rod. Maybe 20,000 amps connected harmlessly to earth. Only four feet from that earthing wire was an IBM PC. All 20,000 amps from a direct lightning strike only four feet away is a 'largest' E-M field. That computer did not even blink. No hardware damage. No program crash. Damage due to nearby strikes is mythical due to superior protection already inside all appliances.

Now, listed are four wires from house to barn. All four have no earthing - two hot wires, safety ground, and neutral wire. A direct lightning strike to AC wires far down the street enters that barn via the house. What does a surge seek? Earth ground. Incoming on those two 'hot' wires. Through the opener. Out via the sensor. To Earth via the already grounded metal door tracks.

Your damage (in this example) is directly traceable to wires entering the building without first connecting to earth. Again, if any wire enters that barn without first being earthed, then nothing inside that barn can do any protection.

Not yet described is what can avert this. In part, because that is futile until you understand why damage is happening. What is lightning? An electrical connection from cloud to earth. A cloud is connecting to Earth via that Sears closer. If anyone wire enters the barn without first being earthed, then only protection is already inside the closer. In this example, a surge, so massive as to overwhelm that superior protection, is using a sensor wire to connect to Earth via the door tracks.
 
  • #39
"""Now, listed are four wires from house to barn. All four have no earthing - two hot wires, safety ground, and neutral wire. ""

Safety ground and neutral are tied together (bonded) in the breaker panel and both are solidly earthed near the meter and again at the transformer, and i think he said at the barn too.

the em pulse from a nearby lightning strike is not trivial.

it can get into house wiring by two mechanisms -

direct connection : If lightning strikes top of a power pole, it gets into the bare copper earthing wire, and that's connected to the transformer center-tap and neutral, so your house safety ground and neutral wires are all connected directly by wire to the bottom of a lightning bolt.
That makes the whole system inside your house elevate well above "earth" potential for the duration of the lightning stroke. It doesn't hurt anything because all the wires "float" together like surfers riding a wave.
I know this first-hand because i was once using a properly grounded Sears metal electric drill when lightning hit my power pole outside. Earth i was standing on was at lower potential than Earth over at my power pole, to which i was connected by my safety ground wire. Quite a shock! A lightning bolt lasts long enopugh for you to say "GAAAHHHH" and throw the drill.
that's why your PC survived - it's a closed box so its internals saw no potential difference.
My drill was fine, it was i who saw the potential difference.

Note that a surge suppressor will see no potential difference either in that scenario.
Fortunately he has underground feed to his transformer, no house-side connection to pole. Unless there's an Earth ground on primary side of his transformer.

it can also get in via induction and there's two flavors of that:
1. if lightning throws a pulse across the electric company's mains it can come through your transformer, inductively coupled, as a stepped down but still high voltage pulse and blow stuff up from simple overvoltage. Surge suppressors are good at arresting those.
2. Old fashioned induction - this is the sneaky one ..
a loop is as i described, an antenna. Being a loop it has inductance. A lightning stroke has fast current rise times hence its magnetic field does too. Any sizeable loop nearby will have voltage induced in by the flux from the lighniing bolt it according to Biot-Savart. This effect tripped my power plant one day. But it requires a close hit. So something at the end of a long safety ground wire can get shaken by induction in that length of safety ground wire between the device and the system earth.. fix is to Earth both exremities, hence the door frames.


that's why i asked about layout, trying to get a feel for size of area enclosed by his ground loops. He has thirty feet of loop completed by Earth between his barn groundrod and his power transformer ground rod.

I wonder how close the barn feed runs to the house feed? That defines area of that loop.

Probably his problem is much simpler and the suppressor will fix it.

old jim
 
  • #40
"I wonder how close the barn feed runs to the house feed? That defines area of that loop."

Not sure what you are asking here. Can you explain further?
 
  • #41
""Not sure what you are asking here. Can you explain further?""

Well if you took a surveyor's sketch of your lot showing house, barn, power transformer etc

and drew in where the power lines are

starting at the power transformer, the line going to house, then the line back out to the barn, then closing that polygon back to transformer by a straight line from barn's ground rod to transformer's ground rod (30 feet you said?)

you should drawn have a closed loop.
is it a long skinny one ( small area)
or a big fat one ( lots of area)
?
Any nearby trees show lightning damage?
Amount of inductive coupling into that loop is in proportion to its area.

Really it's pretty much just an academic question, for were anything significantly out of ordinary i think you'd have noticed other strange electrical happenings by now.

but it's good to be aware of what sort of electrical "antenna" we have constructed with our house wiring.

old jim
 
  • #42
The line from the transformer passes about 10' in front of the barn and into the back of the house. That run is about 75'. Then it comes out of the house about the same place and runs back to the barn crossing over the original line about midway to the barn which is about 50' from the house. There wouldn't be much of a looped area. No trees in the area. There is a well fairly close to both runs. And no, there hasn't been any other problems in the barn or house. Knock on wood!

Thanks for the reply.
 
  • #43
jim hardy said:
""" Unless there's an Earth ground on primary side of his transformer.

Isnt the return on the primary side hard wired to the neutral of the secondary, and then directly to ground at the pole? (At a typical house transformer)
 
  • #44
gtacs said:
Isnt the return on the primary side hard wired to the neutral of the secondary, and then directly to ground at the pole? (At a typical house transformer)
Yes. His claims may apply to certin unique situations not found here. Those grounds must exist as you describe for many reasons - including surge protection.

Meanwhile. the OP describes damage because Earth ground does not exist for that barn. (A wire grounded in the house is not earthing for the barn.) A surge is destructively using the garage door opener to connect to earth. He should be asking how to eliminate that earthing problem. His earthing is sufficient to meet code - for human safety. But insufficient for electronics safety. The OP has an electronics safety problem.
 
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  • #45
WHS SHOCKED said:
We did add a ground for the pole barn where before it was grounded through the house where the power originates. Bill

In the OP he said they added a ground (im assuming and Earth connection). On a typical, professional, installation the barn would be fed from the main DP to a sub-DP via a 100A (mine) breaker. The sub-DP would then be earthed.

Something I am interested in exploring is, you said the "earthing at the house would not suffice for earthing at the barn" do you think the path of least resistance to the Earth would not be via the return on the receptacle it is plugged into? I had never considered this. I believe the OP'er said he had a 50' run to the house panel. I am interested in your thoughts on this.
 
  • #46
gtacs said:
The sub-DP would then be earthed.

Something I am interested in exploring is, you said the "earthing at the house would not suffice for earthing at the barn" do you think the path of least resistance to the Earth would not be via the return on the receptacle it is plugged into?
As I kept saying in most every post. That barn is not earthed. It is earthed to meet code. Code only cares about human safety. It is not earthed for transistor safety.

The expression was posted repeatedly. "low impedance (ie 'less than 10 foot')" . Or "short (ie 'less than 10 feet')". That is why the barn has no earthing. Impedance - not resistance - is important. A low resistance wire can have high impedance.

A similar example. A 200 watt transmitter is broadcasting on a long wire antenna. Touch one part of that antenna to receive a well over 100 volt shock. Touch another part of that wire to feel zero volts. Why two different voltages on the same wire? Electrical concepts that an electrician would not and need not understand. Code is why he is not trained in these other relevant concepts.

That barn must have its own single point Earth ground. Every incoming wire - no exceptions - must connect low impedance (ie 'less than 10 feet') to those earthing electrodes. Four AC wires enter. All four must connect short to earth. One might connect directly (but that is not described). Others must be connected via a 'whole house' protector. Since WHS SHOCKED does not have this, then surges are inside the barn finding Earth destructively via the door closer.

Earthing must both meet **and exceed** code. That Earth ground 30 feet away at the house means the barn is sufficient to meet code - but not provide surge protection. Impedance is only one reason. If the necessary concepts are understood, then zero volts and 100+ volts on two different antenna wire locations also is obvious.
 
  • #47
his wire lengths are insignificant compared to wavelength of 60 hz, so i see no standing wave issue.

Electricity wants to get back to where it came from. (KCL)
Lightning wants to get back into earth.
Power surges want to get back to the transformer winding (which has been checked by power company to be well earthed) .
If that ground rod at barn goes deep enough it should do a pretty decent job for both.

i would think.

That garage door opener has a design flaw and that's why there is a "protector" made specifically for it.

old jim
 
  • #48
jim hardy said:
his wire lengths are insignificant compared to wavelength of 60 hz, so i see no standing wave issue.
You are assuming a surge from the wrong source. Destructive surges are microsecond events. Protection installers are gnarly even about sharp wire bends, ground wires not inside metallic conduit, no splices, separation from other wires, etc. Low impedance is not about a thicker wire. Lower impedance is about shorter wire - ie 'less than 10 feet'.

Safety ground in receptacles can not perform effective earthing due to those and other requirements. For example, a 50 foot wire from a receptacle to breaker box might be well less than 0.2 ohms resistance. That same wire may be 120 ohms impedance to a surge. Code worries about resistance for human safety. Impedance and equipotential are critical factors in protecting that door closer.

One of many reasons why a house Earth ground does not Earth all wires entering the barn. Yes it does Earth for 60 Hz power. But a surge current typically is not 60 Hz power.

If 60 Hz power was on that antenna, then same voltage would be everywhere. Electric concepts to understand surge protection involve factors well beyond what a typical electrician learns. I was not talking about standing waves. I was discussing why a good electrician would not understand nor solve the OP's problem. And why others must appreciate the significance of low impedance (ie 'less than 10 feet').
 
  • #49
westom said:
A similar example. A 200 watt transmitter is broadcasting on a long wire antenna. Touch one part of that antenna to receive a well over 100 volt shock. Touch another part of that wire to feel zero volts. Why two different voltages on the same wire? Electrical concepts that an electrician would not and need not understand. Code is why he is not trained in these other relevant concepts.

Westom, could you expound on this please, I like, Jim, thought you were referring to standing waves on the wire, and could not relate that to the problem. I looked for info. on long-wire antennas and could not find anything of value.

As far as the whole house protectors you mentioned, I did read a fair amount on those. It seems to me to be a good idea; apparently you can have your electric company install one for a nominal monthly fee. However, you still to use point of use protection as the whole house protectors handle higher spikes but react slower than the point of use
 
  • #50
""I was not talking about standing waves. I was discussing why a good electrician would not understand nor solve the OP's problem. And why others must appreciate the significance of low impedance (ie 'less than 10 feet').""


You seem to feel OP's problem is a simple common mode pulse
and i feel it's a simple normal mode overvoltage

his surge protector sounds like it attacks both problems

so we'll probably never know

but i respect your opinion.
 
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