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Posted

Crossy, sorry for your loss, but as a wild consideration I'm wondering if your MOV's (I think they're the red colored ones) are a bit cheap and nasty, and the specs are not as quoted.

I remember when looking at the price you paid from AliExpress (I think) was a lot less than the price of the brand I bought. I bought the Schneider brand. Wonder if you buy one of these as a replacement and compare what happens between MOVs on your next hit.
Just a guess, but specs don't seem to be specs these days.

Also with the gate controller PCB, I know you said all the power supply OPs are OK, but have you checked any zener diodes?



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Posted

@carlyai indeed, although mine didn't come from AliExpress, I got them retail in Shanghai (is that any better).

 

Like I noted earlier:-

 

On 5/6/2018 at 11:45 AM, Crossy said:

Like many preventative measures you never know if they are working, you only know when they don't.

 

I hang out my used socks to keep the tigers away, I've never seen a tiger so they must be working :smile:

 

I may try to test one of the big MOVs trigger voltage (I have a spare cartridge), the small blue MOVs have been checked for trigger voltage and they are good.

 

For the controller, I've checked all the components I can, a lot of it is surface mount and with no diagram it's really a non-starter. To be honest, if I were to charge myself my normal rate I've already paid for a new one.

 

EDIT I may bite the bullet and invest in a Citel front-end unit, they are one of THE names in surge protection, but the $$$ is a bit scary. http://www.citel.us/

 

 

Posted

@Crossy . More wild guesses.

When electrical storms start hitting near our place, the 3 phase SafetyCut trips. I can suppose that with a lightning ground strike the earth potential at that point rises for a poofteenth of a second and the phase and neutral currents are not the same, therefore the trip. Whatever causes the current imbalance, the trip removes power to the house.

I'm just wondering if your mains earth leakage breaker trips as well.

Your area seems to be prone to lightning strikes.

You could go radical and set up an outside UV detector and calibrate it for close lightning strikes. Then using the IoT disconnect your power and restore it after the storm has passed.


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Posted (edited)
3 hours ago, carlyai said:

Your area seems to be prone to lightning strikes.

You could go radical and set up an outside UV detector and calibrate it for close lightning strikes. Then using the IoT disconnect your power and restore it after the storm has passed.
 

Lightning produces an electromagnetic pulse which can be detected using a radio receiver. The old Marconi spark gap transmitters (RMS Titanic) used the same principal and explain how it all works.
 
Some transmission towers use radio receivers to detect the unique signal generated by nearby lighting strikes and reduce risk by switching to battery power.
 
To this day lightning still remains a mystery and many theories surround how some areas suffer more lightning strikes than others. There are simple explanations how lightning starts as rising charge in the clouds that eventually reaches a point where it overcomes air resistance. What is not clearly understood is how charges manage to jump large air gaps when the charge measured is not high enough to do so. This is where magnetic field and cosmic ray theories attempt to explain the mystery.
 
Edited by Fruit Trader
Posted

I think we can add the photo-switch that controls our outside lights to the list, it went bang last night, I'm assuming something internal got weakened.

 

Apart from the gate controller we are now all back up and running although "something" caused the lights to flicker before the breaker opened last evening (not the photo-switch). The breaker reset ok but there's the smell of burning electronics in my workshop (ok, stronger than it is usually) the source of which I've not been able to identify as yet.

 

Evidently the Magic-Smoke has come out of some device that I've not tried using yet.

 

  • Like 1
Posted (edited)

last night we had a storm with many nearby lightning strikes.
after that some power circuits did not work anymore and I will

have to have to replace a few broken breakers. the wierd thing is, 
the breakers did not tipping ... (why?) 
(i replaced one breaker, and it worked again ... now i need to buy 
a few more to replace all broken ones)

one of my nighbor has the exact same problem ...

280516.pdf

Edited by motdaeng
Posted
1 minute ago, motdaeng said:

last night we had a storm with many nearby lightning strikes.
after that some power circuits did not work anymore and I will

have to have to replace a few broken breakers. the wierd thing is, 
this breakers did not tipping ... (why?) 

4

Try turning the "dead" breakers off then back on again. They are simple beasts and a lightning surge shouldn't kill them (a direct hit will).

 

Posted
6 minutes ago, Crossy said:

Try turning the "dead" breakers off then back on again. They are simple beasts and a lightning surge shouldn't kill them (a direct hit will).

 

thank you for your reply. I did it already (more than once!), also i did put

the test button an the safe-t-cut ... I am glad having not more damage,

only replacing a few breakers ...:smile:

Posted
1 minute ago, johng said:

Ants "Kill"  lots of breakers and switches !

Yeah, the little itsy-bitsy ones really like the electric fields for some reason. They bite like the devil too.

 

Most of our exposed electrics has ant killer or moth balls inside to keep the beasties at bay. 

  • Like 1
Posted (edited)
8 minutes ago, Crossy said:

Yeah, the little itsy-bitsy ones really like the electric fields for some reason. They bite like the devil too.

 

Most of our exposed electrics has ant killer or moth balls inside to keep the beasties at bay. 

the cause in my case is definitely the thunderstorm with the lightings ...

not only me, also my neighbor thinks we all had some direct hit!!

(who knows who is right?)

this seems the reason. but only 5 of 21 breakers need to be replaced :saai:

at my house ... it is just very strange and a new experience for me!!!

 

Edited by motdaeng
Posted

'Ants "Kill"  lots of breakers and switches !'
If nothing adds up electrically and strange things are happening with the power and lights, good chance it is the ants.

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Posted

 

Our first Issan fuse box was just a big knife switch and a buss fuse. During a thunderstorm, I opened the knifeswitch thinking, I'm all set now.  Then we got a close lightning hit. The lightning jumped right across the knife switch and blew out a couple of lights. 

 

Now we have a real fuse box and so far we've had a few close strikes that tripped the main breaker and no damage. 

 

I now know a direct hit can fry everything, so I'm wondering, would it be possible to put a big plug in the line before the fuse box. Then just unplug that instead of unplugging every appliance during a thunderstorm?

Posted

Anything that conducts can/will carry a surge caused from lighting.  That is likely to be your mains but could also come from the cable running to the garden lights or the steel in your roof.  

Posted
2 hours ago, zlodnick said:

I now know a direct hit can fry everything, so I'm wondering, would it be possible to put a big plug in the line before the fuse box. Then just unplug that instead of unplugging every appliance during a thunderstorm?

Yes you could make an isolation loop using suitable plug and socket but a ground isolator might be a better solution. These isolate you from the power line and put your side to a solid ground.
 
If you have expensive stuff to protect there are lots of expensive solutions to reduce risk. Paying for local power line arrestors at a transformer is one example.
 
And lets not forget the thousands of spikes dancing around the grid not created by lighting.
 
Posted
Am I missing something or would it not be easier to install lighting rods?
Then you've got to make the lightning strike the rods.
I've seen lightning strike a tree in a small valley, even though there was a 300' TV tower very close.
Darwin amphitheatre.

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Posted
Then you've got to make the lightning strike the rods.
I've seen lightning strike a tree in a small valley, even though there was a 300' TV tower very close.
Darwin amphitheatre.

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See? I’m sure the tower had lightning rods...;o)
Posted

Rods wouldn't have saved us in this case, the hit was on / very close to the supply cables.

 

We did have a direct hit to the roof a few years back which blew off a couple of ridge tiles and fried a bunch of electronics.

 

Cost of fixing the roof was minimal. At the time I did consider installing rods, but the cost was going to be silly and with a hit that close I'm not convinced they would have made a lot of difference to the electronics that died.  

Posted

Our insurance compels is to have rods every 10m along the ridge-vent at the plant. We’ve been hit at least once that I know about without incident.

Not sure why the cost would be prohibitive, basically a ground-rod on the roof to a ground rod in the ground.

I travelled with a carnival back in the ‘70s & ‘80s. Five of us were setting the track on a “Himalaya” ride in Buffalo when the ride got hit. Big spark from the track we were holding to the jack-stands. We all got shocked, one guy shat himself...

Posted

They recently replaced all the lightning rods where I'm staying  (90 buildings)  the old ones had thick copper cables running all along the roof ridges and it was stolen from almost every building..no idea how much this new setup cost, but I would imagine significantly less as there is no copper on the roof ridge now.

 

lightning.thumb.jpg.87514be1489bf2c79b3a7cc1d60ca44b.jpg

Posted (edited)

In the next two days i'm planning on putting some protection up.

It will run from a ground rod up to air rod on top of shed cable pole(left of house)

over house to pole on tank stand on otherside with air rod then down to another ground rod.

16 sq mm copper cable.(costs all up 4500 baht)

Just want to know if that's enough to give peace of mind if sitting under it in a storm.

Cheers

 

20180516_163554.jpg

20180521_181248.jpg

Edited by farmerjo
Posted
1 hour ago, farmerjo said:

In the next two days i'm planning on putting some protection up.

It will run from a ground rod up to air rod on top of shed cable pole(left of house)

over house to pole on tank stand on otherside with air rod then down to another ground rod.

16 sq mm copper cable.(costs all up 4500 baht)

Just want to know if that's enough to give peace of mind if sitting under it in a storm.

Cheers

 

An old quote for fitting ridge line conductors to our work shed shows 35mm copper connecting cable. I originally specified the whole setup but cant remember whose standard I used. Our rods are solid copper 5 spike made in China.

 

Use Google to find conductor size from various standards. 

  • Thanks 1
Posted

Out of interest, if one had a wi net tower about 10 metres from the back of the house, is it advisable to bang an earthrod into the ground at it's base and clamp onto the tower, any safety advantage to doing this? The house main earth rod is at the front of the house so about 25 metres away from the wi net tower?

Many thanks.

Posted
9 minutes ago, tdm said:

Out of interest, if one had a wi net tower about 10 metres from the back of the house, is it advisable to bang an earthrod into the ground at it's base and clamp onto the tower, any safety advantage to doing this? The house main earth rod is at the front of the house so about 25 metres away from the wi net tower?

2

If your tower is steel it will be pretty well grounded anyway, adding a rod (and a lightning conductor at the top) may be an idea (how tall is it?), see what ToT say.

 

Our WiNet antenna was on a concrete (power) pole about the same distance from the house when we took a direct hit to our house roof. Fried the router comprehensively.

 

Posted

Hi Crossy, yes the tower is steel, about maybe between 10 and 14 metres high by my loose estimate, the base sits on the grassy ground, can't remember if it actually goes into the ground much though I put some concrete around the base to stabilise it alongside the three wire supports which are held in place by metal pins banged into the ground, no conductor at the top but if the earth rod may help then that's easy enough to instal. Thank you.

Posted

My 1st bit of peace of mind.

This is the highest point of all adjacent buildings.

I doubled up the 16mm copper wire to make 32mm and the ground rod is in 3 metres.

For now as i don't have the correct copper cable(what i read they say it should be braided),i will put another single one up on fatherest side of the house on the tank stand.That would put the two rods approx 25 metres apart which they say is a bit far but as they say,better to have something than nothing. 

It's not to save appliances,hopefully just the family

 

20180601_105204.jpg

  • 1 month later...
Posted (edited)

We had an incident in our village last night that readers here might find interesting...

 

About 8pm with moderate rain, an extremely loud BANG occurred seemingly directly above.  The lights went out immediately.  I hadn't seen a flash and my hair didn't get frizzy so I thought it must have been a cloud to cloud strike.  I started out to fire up the genset but then noticed that my garden lights were on.  FYI: I have two CU - one for upstairs and one for down.  The garden lights are on the up CU.  Everything down was dark.  So, I went upstairs where the mains enter and I have two AVS (for up and down) as well as watt meters to show what's going on.  The mains showed normal (high) voltage and the up AVS showed normal adjusted voltage and the normal 2 amps or so.  The down AVS had tripped.  I turn on and it started with a bang as usual and then showed the normal 218v but with no amps.  So, I went down to check that CU and found the main tripped and a also a circuit that includes the pump along with several outside outlets.  I turned those back on and everything came back on.  I thought for sure I would find my TV's gone and/or the inverter refrigerator but everything looked normal.  FYI: I don't have any surge suppression but whatever happened tripped a 40a breaker.  I checked other things that were plugged in at the time - like a phone being charged - and everything was fine. 

 

Now, I just find out that I am the only house in a circle of about 20 that did not suffer damage.  Everyone else has a dead TV.  Some have a dead refrigerator.  And several have outlets that "blew up" where something was plugged in.  A friend who had her phone charging says her phone got fried.  One neighbor reports looking outside at the time of the strike and saw a fast moving fire ball going down the street.  I'm pretty sure the only protection the neighbors have is a Chang switch that might be fused but more likely just a piece of wire.

 

Why did my breakers open in time to save everything?  I don't know but very happy they did.  Why didn't it affect my upstairs.  I don't know but we are at the edge of the damage circle and the down CU  and pump are closest to that where the up CU is on the other side.

 

There you go.

Edited by bankruatsteve
Posted

I think it may have had something to do with your 2 stabilizers.

TV etc were damaged in houses in our village, except our place, when PEA reconnected the power after an outage.

I have stabilizers on the incoming 3 phases.

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  • Like 1
Posted
3 minutes ago, carlyai said:

I think it may have had something to do with your 2 stabilizers.

TV etc were damaged in houses in our village, except our place, when PEA reconnected the power after an outage.

I have stabilizers on the incoming 3 phases.

Sent from my SM-J700F using Tapatalk
 

Could be I suppose.  Both AVS are together along with mains entry and up CU.  Again, what tripped are the AVS for the down CU, a 20a breaker for the pump, and the main 40a breaker.  Nothing else in my home was bothered and there was no power outage.  Forgot to mention, almost everyone else had their F-lights burst also.  

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