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Inside an African lightning protector - and candy
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- Опубликовано: 13 июл 2024
- It's cheap - it does work - but would you trust this in your home?
This voltage transient shunting device was sent by Frankhe for our exploration. He also sent some candy and some combined metal oxide varistor and gas discharge tube devices.
I'm used to seeing surge protection devices that have a thermal safety device, as the varistor disks gradually break down and can start to pass current continually at lower voltages, resulting in heat.
The internal construction makes me wonder if the MOV/VDR disk was supposed to be sandwiched between the two copper electrodes. Or if those electrodes were designed to go into a ceramic ring to act as a spark gap.
If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:- www.bigclive.c...
This also keeps the channel independent of RUclips's algorithm quirks, allowing it to be a bit more dangerous and naughty.
#ElectronicsCreators
That laugh when testing the "copper" disk made my day.
Same! The "Maaagnet!" was the best.
TRUST NOTHING!
And he proved himself correct with that mindset instantly
Maybe they're bimetallic for a reason!
@@abitofabitofabit4404 possibly, but for what reason?..
..thay was pointed aginst eachother anyway, that makes a litte sense, tha fact its magnetic is interesting... its possibly at high enugh current those two will separate (magnetic separation), but thecurrent need to be darn high .. high enugh to make it useless as aprotection device i belive, and as a lighetning protecton, well, thay will weld together long before thay can separate likely, and as its desiged, the 'shims' are alot larger than the varistor and the lead thats clamped to it, so u have a gap beteen conductors that marginally larger than the with of the varistor, any lightening strike would jump it like it waseent present...
...but as a protection against surges, starting/stopping lager electric motors etc it probably work.. I def wouldent trust it doing any lightening protection
@@Patrik6920 Well, if directly struck by lightning, even if it were actual copper, it would still blow itself apart. Eddy currents get weird when current is really high. Everything that carries current tries to escape from everything else that carries current. Very violently. But if that happened, you have already failed to save your devices from the lightning.
In my younger days I used to install temporary IT systems for diplomatic conferences all over Africa. This meant planning and doing everything from electricity supply, local network, Internet, Wifi... Cheap Chinese stuff was everywhere. Half the time we were lucky if at least the toilets worked.
By planing do you mean woodwork?
My theory was we got all the parts that other countries rejected
That's a very racist view😡
@@TheCatLady65 No that is just reality.
Funny, in my younger days, I setup connections to diplomatic missions in 3rd world countries using serial connections over normal phone lines & UUCP...... There was no internet, WiFi or cheap Chinese anything. Often not even electricity. It was a good connection if the latency wasn't over 300ms (aka not a satellite connection)
When I see really cheap stuff, I'm reminded of John Glenn's comment:-
"As I hurtled through space, one thought kept crossing my mind - every part of this rocket was supplied by the lowest bidder. "
😂😂
I think you will find it was Alan Shepard and the quote was "The fact that every part of this ship was built by the lowest bidder." It was from Gene Kranz in his book Failure Is Not an Option. I don't know of any other sources but have heard it attributed to Shepard many times. Anyway it's still a bloody good quote.
And did you know that the space suits were manufactured, at least in part, by Platex, the bra/girdle company? It’s because their stitchers are the most precise!
I think the original quote also mentions the tons of fuel involved.
This makes the requirements your safety net?
That mischievous chuckle when the "copper" clacked into the magnet was priceless
Perhaps they have made an error in the assembly? Maybe the MOV should be sandwiched between the "copper" plates, so they could also act as a spark gap?
Yup, I immediately though the same thing. The shim must have been intended to uniformly clamp and spread current across the MOV slug's surface on both sides instead of letting the puck only make contact with the other terminal's spring. Definitely looks like an assembly error to me too.
Same, that is why that batch was sold to Africa
I dunno, I'd go with parallel for MOV and gas discharge. As the MOV begins to fail and eventually open due to vaporization, the gas discharge would engage and continue protecting at higher energy levels.
Yes, vaporization, I've had MOV's fail a foot away from my face, nice ball of plasma as they short and vaporize.
@@spvillano The normal failure mode for MOVs is increasing leakage current. That is why they should always have some sort of thermal fuse to disconnect them once they get too hot.
If a MOV explodes, it was either defective, got damaged by a gross overload or was worn well beyond its service life.
Could be slightly quicker to assemble with the "copper" disks together then the MOV. Who would ever find out?
They Hymag unit is meant to be used after a breaker, not direct across the line, though there it will be protected by the 100A incoming breaker anyway. As a matter of interest it likely was made at one of the highest factories in the world, as Hy Mag has assembly plants in Lesotho, a land locked country, which is entirely made from mountain ranges. they are needed, because the mains here can be rather rough, and there is a good chance of the incoming supply rising to high levels because of loss of neutral, because that copper got stolen in your substation, or a phase was lost upstream. Or you could have what a friend has, and no power since Friday, because some somewhat drunk person parked their car in the local substation. They and the 4 passengers in hospital, and still awaiting a new transformer to be connected up, after the car totally demolished the brick and concrete substation, plus the fence and road barrier that was in the way.
I had to replace "in" with "into" to make sense of the phrase "...parked their car in the local substation". 😂
Ouch though. 😯
@@DerMarkus1982 Yes they put the car into the substation, and sort of took the area out.
I can't be the only one who saw the title and thought "in Africa, lightning protectors double as candy?"
Enjoy your treats! Thank you for the video.
The components inside the big surge protector are more chunky than I expected. I was anticipating a much smaller MOV and maybe some rudimentary thermal protection, but clearly a fuse was completely omitted.
As you pointed out rightfully so, the screw terminals are exposed and therefore not up to our western standards. A good thing about people in African countries is that they generally don't poke around in electrical installations. They are told electricity will kill them and they are not wrong about that.
I did however see many occasions where people in places like Zambia and Zimbabwe stuff a type C (CEE 7/16 Europlug) connector in a type G (BS 1363) British style wall outlet. And in order to make that happen they poke something in the PE (earth /ground) hole to defeat the shutters that shield the L and N holes on the socket.
A connector rated at 2.5 A stuffed in a socket that is able to provide 32 A. What could possibly to wrong?
I took a couple of type F (CEE 7/3 Schuko) extension cords from home, fitted each with a fused type G (BS 1363 UK) connector and gave them away to my friends in Zambia. Making things a little bit safer.
Regarding the GMOV, a combined MOV and GDT. The company Bourns claim in their sales pitch that this hybrid component ages less quickly and therefore has an extend life expectancy compared to a standard MOV. The added GDT does however results in a 300 ns slower response, but it seems that most component downstream can absorb this energy.
Regarding the Europlug: apart from the mechanical and contact problems of stuffing that in an UK outlet, I don't see a problem here. Europlugs are made to be plugged into outlets which provide much more than 2.5A (usually 16A).
@@moe.mThe problem would be the cable, not the plug. The fuse in the plug should be chosen to be appropriate for the cable. A 2.5A cable protected only by a 32A circuit fuse is most certainly a problem.
@@chrishartley1210 This doesn't seem to be a problem, as there is no other way to use an Europlug. E.g. in Germany, you always plug them into an 16A outlet, 2.5A outlets do not exist.
@@moe.m Which is why the UK plug is regarded as the safest in the world.
@@chrishartley1210 True, but why is it so incredibly clunky while only supplying 13A?
I would much prefer the Swiss T12/T13 plugs, there are versions with an integrated fuse.
Yes. I lived Johannesburg on the “highveld” 6000’ above sea level in South Africa. This is a place that has one the highest number of lightning strikes in the world. I got tired of having my electric gates, microwave, tv etc etc destroyed by lightning. Even a strike near the mains feeder cable absorbed the emp. and after consulting with an expert I installed a set of MOVs in our main switchboard. Many people had plug tops with a mov inside. Apparently if you have a strike you should replace the mov. Was never sure how I could test them.
A proper surge protector will have a circuit that measures the leakage current across the MOV. When it increases to an unacceptable level indicating damage, a "protected" light will extinguish and in switchboard/installed applications, an annoying buzzer will sound. It also needs a thermal fuse, because in cases of catastrophic damage, the leakage current will increase to the point the MOV will heat and burn. You shouldn't use plain MOVs for this reason.
Which is why you need made in South Africa ones from CBI for example. Your solar panels will need DC ones too to protect them and your inverter\charger 🌚
@@straightpipediesel It was about 30 years ago & I no longer live there. The company that supplied them were consultants for lightning protection on a big steel mill upgrade and expansion project that I was working on. The main problem was that the incomer switchboard & meter was at our gates with a cable running underground for about 60m (we had a long drive way) up to the house. They seemed to solve the problem at the time and the house is still standing .😀
@@andrewallen9993 The company that supplied them were our consultants for lightning protection on a steel mill project (Middleburg) I was working on - pretty sure they were upto spec at the time but it was 40 years ago.
Dunno why, I suddenly had to pause the video and go get myself some chocolate.
Ditto...😅
The Tony's chocolate is quite nice
"Trust nothing." 😂
Every time I watch one of your vids, Clivey Boy, my eyes are always drawn to the burn in the table you made with the plastic stapler thingy.
They have to have special lightning stuff there... for the rains... down in Africa.
Mouth is watering profusely upon seeing humoungous african chocalate bar - lucky you! Had to shut down and make a junk food run immediately if not sooner.
South African house supplies are on average 240V. Incoming supply from utility comes into the house DB board via a combined earth leakage and over current circuit breaker. The surge arrestors are connected between Live and Earth, Live and Neutral, and in some between Neutral and Earth. The arrestor relies on the earth leakage unit to clear the fault if any of them goes short circuit. Earth leakage units operate around 25mA difference between Live and Neutral currents in the earth leakage unit.
Nicely informed. Thanks. I think our standards and discipline is sometimes unfairly judged based on Hollywood perceptions...
Talking about lightning here, look at the shape of the copper discs. They trap a volume of air between them. If an extreme amount of current is coming for a brief moment the intent may be to heat and expand that trapped air "explosively" and blow the discs apart within the housing, creating a temporary self-sustaining spark gap.
It may not save any sensitive electronics but I gather the idea here anyways is to prevent house fires.
The thing is that a fuse or breaker is specifically supposed to extinguish arcs, not sustain them. A "self sustaining" spark gap would pass almost as much current as the breaker would while closed, since the entire point of a spark gap is to act like a closed switch when there's an arc across it. Those are almost certainly just some locally available washers that are about the right size to act as shims
There would have been a spark gap if the MOV puck had been between the copper-plated shims. That would also have provided more even clamping force and current distribution across the puck too. Looks like an obvious manufacturing error to me.
I have inspected dozens of household fuse panels after lightning strikes. The black device would be great protection and worth its cost 100's of times over after a direct hit. Fitted behind a 100A breaker it will not save the latter but likely everything downstream. Nothing wrong with copper coated steel discs. The skin effect makes most electrons travel on the surface anyway even at 50Hz. The steel plates would also act similarly like crunch zones on cars, slowly dissipate the resulting heat. Overall the product enjoys great corrosion protection and good longevity.
Skin effekt does not really come into effect at 50Hz when talking about the scale we have in typical homes as the skin depth is over 9mm in Copper. So this would only be relevant for beefy bus bars etc. you typically do not see in home installations ;)
But you are still right: when talking about lightning stikes effective frequencies are much higher then the 50Hz of the grid. So the current of these impulses (not of the normal operating current!) is carried mostly on the surfaces.
The skin effect depth at 60Hz is 8mm. As a rule of thumb, if a device fits in your hand, the skin effect at mains frequency is not relevant to its operation.
I reckon, there was a MOV that has the correct size that sits in between those plates that then leaves a flashover gap. In this case it looks like if you put it in between the resulting gap would be too big. Perhaps someone buying the parts at the factory has done a switcheroo to a cheaper, wrong part without understanding what it's about.
Such “switcharoo” is a serious violation against plenty of internal (and external) departments including the clients, higher management and electrical engineering. Even by third world standards. I feel like i’d like to refute that.
@@BritishEngineer maybe in Britain, luckily. But I guess in some areas it would be considered the fault of the company selling the finished device, or the importer if sold abroad, for not regularly auditing what they are getting from the external factories...
@@BritishEngineerTHis is China we're talking about.. You think they give two flying fluffs about violations?
@@BritishEngineerThe fact that it's wrong to do a thing doesn't in any way prevent the thing from being done. There's thousands of examples of people taking shortcuts they shouldn't, many of them resulting in worldwide infamy through catastrophic incidents, and despite how well known these sorts of incidents are we keep getting more of them so the shortcuts are clearly still being taken. Plenty of people will push the boundaries until something breaks, and this device hasn't completely broken yet.
Strobe Whoofles! Of all Dutch sweets, licorice (especiually when soft and salty) is by far my favorite thing.
I haven't seen a combined gas discharge / MOV either.
I had some liquorice in a small tin, just tiny bit but really tasty. It was years back I was still at school. and Im 60 now. not sure it they still sell it. and RUclips no doubt will say something the sweets name was S p u n k 🤣🤣🤣🤣
Interesting configuration. The dimensions of the GDT element suggest a pretty low flashover voltage, yet probably enough to protect the MOV element from lower-energy "nuisance" trip events that would impact its lifespan. I'll be sticking to my DIN rail cartridge style arrestors (with clear failure indication) for the moment. Incidentally, Mr C - remember doing a video on those plastic KAM press-studs, seven years ago? My overalls have finally passed the "point of no return", yet those cheap plastic press studs were still working just fine!
Yeah, the plastic studs are surprisingly tough.
I'd have never thought that HD videos of color still photos would be such great content but you somehow manage to make it work. ;)
Littlefuse makes MOV's with series thermal fuses or PTC's integrated into the package. Very useful.
A CR2032 looks like it would fit in there nicely. You should try it!
If the varistor is sandwiched between the copper plated steel plates, the outer edges of the plates could serve as a gas discharge gap in the ambient air. The breakdown voltage would be unpredictable, but for a lightning strike it should react fairly well and limit the spike to perhaps a couple kV. To really test it may require a large capacitor charged to perhaps 10kV and a current limiting inductor of very low value simulating the feed from the service drop's transformer.
The advantage of the integrated gas discharge tube on the MOV, my guess: MOVs are aging during normal operation, without ever clamping, just exposed to normal mains voltage. With that gas discharge tube in series, the MOV won't see any voltage across it, only during a transient event, when the voltage reaches the brekadown voltage of the gas discharge tube. So this arrangement was probably created to prolong the service life of the MOV. That super tiny gas discharge tube probably has a very low brekdown voltage, it is intended to break down just above the nominal mains voltage.
Interesting fact, the earth leakage circuit breaker was developed in South Africa by Fuchs Electronics.
Mr. C. J. Fuchs was of course a licenced and certified plumber and drain layer 😀
Well as someone from South Africa I can say I have more faith in South African (not other African countries) electrical installations than I do in Some British installations. When I moved to the UK in the mid 2000's I was surprised by the lack of earth leakage switches on most domestic installations. its only in the last 10 years or so I've seen RCD switches appearing in residential installations. I'm not going to say i'm an expert on UK electrical systems, I did study partially in South Africa for domestic electrical installations but I did give it up and switch to electronics instead as I had more of an interest in radio at the time, probably not my smartest move.
@marcofixit
Sounds like the safest move☺👍
If by 'earth leakage switches' you mean ELCBs, then they have been out of favor for a long time due to false tripping caused by a bunch of reasons. RCDs are installed nowadays.
You think some of that might be related to how old the electrical systems are in cities/entire countries? My theory (at least here in The States) some of our large northeast cities were among the very first places to be electrified, but the updating of those systems and grids were never really mandated unless there was a major change to the buildings housing them. What you can then observe are buildings that are structurally quite old, but have undergone multiple "face-lifts" to their facade. However the improvements were just shy of requiring upgrades to the mechanical systems. These appearance updates were deliberately planned to avoid an expensive mechanical retrofit. So we see newer looking buildings with ancient and very deficient plumbing and electrical - with no legal requirements to update. Same with the cities infrastructure. Lots of patching to save money maybe?
RCD protection became a requirement (BS 7671) for most circuits in U.K. installations in 2008. Before then, in 2001, RCD protection was supposed to be provided for any sockets that may be used to supply outdoor equipment. In between these dates there were various amendments to the regulations, each time extending the requirements for RCD protection.
And RCDs suitable for consumer units (breaker boards) or as separate units have been available in the U.K. for over 35 years.
Where individual circuit protection is wanted, a RCBO can be fitted replacing a MCB and a RCD with a single unit.
However, there is no retrospective requirement to update existing installations unless either a new consumer unit is being installed, a new circuit is being provided or there is a significant amount of rewiring being carried out. Or the rewiring is for a circuit where RCD protection is now a requirement.
As the existing U.K. systems are seen as a safe system by home owners and landlords, often an installation is only upgraded when it has to be or the property is being completely rewired.
@@markcohen4599 yep. My old SW Philadelphia row home had indoor plumbing added along its history, originally not having much more than a water closest and outdoor outhouse. Originally had gas lights, some pipes terminated in the basement and left in the walls and the greatest fun...
Knob and tube wiring, cloth covered of course, that all still in use in the foot tall space between the upper floor ceiling and flat roof.
This thing was engineered by that famous Nigerian prince who's always trying to give me money.
9:41 _"MAAGNET"_
Brass ... -ISH! 😄
@@DerMarkus1982 haha
My childish mind immediately responded to the term lightning arrester with the sentence, "Oi! You got a license for all that banging and crashing araahhhnd mate? People are trying ta sleep and you're lighting up the night sky? What's wrong wiv you Son? You're nicked. Get 'im in the van Steve... BONK! (just in case 'e was finking about gettin' lively Sarge)"
I wonder if those "copper plated steel" disks are actually bimetallic. If so, they might flip to their alternate stable position when they get hot, creating a gap.
I was thinking along similar lines. But instead of the discs being bi- metallic maybe the c shaped arms holding it might release when they heat up. Time to fire up the de-solderings station.
@@ThorMccammon A paint stripper heat gun can help to warm things up.
no way there is a bimetallic effect with the geometry that solid, it would be beyond their yield strength
@@ThorMccammonThat's exactly how they work, my families company build specialised commercial vehicles,the pumping stations and desalination plants are fitted with similar self resetting arresters for lightning strikes. Although theirs are about the size of a car battery,very heavy and fully waterproof,being potted and sealed into a plastic and pressed galvanised steel housing,but their functional construction is almost identical.
I made a spike buster a awhile ago the fast nature of spikes actually passes through the mov protection for e first few ns and blew up the TVS diode which was further down the circuit.
I lived in South Africa in a suburb of Jo'burg which had lots of low grade iron ore surrounding the town, rusty red soil everywhere. During the summer there were massive electrical storms with strikes everywhere. It was prudent to unplug any critical equipment in the house when you were not at home, in my case a QUAD amp tuner and deck. If you were at home listening to music or watching TV during a storm, wise men unplugged ! At that time lightening protectors were not fitted to household fuse boards (and I wouldn't have trusted them if they were !). Any local strike, and there were many, travelled a long way to your local earth and cooked whatever it came upon. A friend of mine got a significant jolt taking a shower during a storm. Out in the countryside, many of the local African farmers used a traditional method of lightening protection, a long thin pole about 25ft high with a red flag on the top next to their houses...........
Those tall poles are often near houses that have a thatched roof. Although every house in the open field could do with two or three of those poles.
The Johannesburg area is notorious for its lightning strikes. To unplug is the best advice you can give a friend. Even with the best lightning arrestors I wouldn't trust my devices to be connected during a storm.
"pure chinese copper"
The MOV/spark gap combo is a nice idea, both being used at the same time on protection circuits. So having just one component is pretty neat.
That chocolate bar was just screaming "come on snap off a piece, you know you want to".
Edit: I thought it was to lower clamping voltage but the gas discharge tube is actually in series with the MOV, so it’s there to stop leakage currents. Might also potentially protect the MOV when it goes low resistance, but the tube can do the same thing if there’s a lot of sputtering inside. Actually kind of a cool concept of using the gas discharge tube to stop low level leakages that degrade MOVs over time, but I’d still want the thermal fuse just in case.
They can also get the clamping voltage down closer to line voltage, becaus the GDT has a sharper knee than the MOV.
@@aniragraham3077 That’s what I thought as well but the GDT is in series with the MOV instead of parallel. According to Eaton that makes these it’s to use its sharp knee to add some hysteresis to the MOV so it only conducts for larger transients. Saw this when Clive tested it in that the trip voltage was higher than the clamping voltage. It looks to be geared towards industrial applications where noise from equipment can prematurely age the MOV.
Some comments on this video remind me of something very unusual that happened years ago where I live:
The lightning might have struck very close to the house because it made a loud bang like I had never heard before.
And at the same time a bright flash appeared at the electrical panel, where there is top to bottom the consumer unit, a box with fuses that only the utility company is allowed to access then the main breaker, which also popped right after the flash.
But the weirdest thing in this event is that there's got absolutely no damage left afterwards.
We switched the breaker back on and it worked just like if nothing had happened before.
No scorch mark or soot to be found anywhere either.
So to this day I still wonder where the flash actually came from and also why the main breaker popped.
I mean, it's not designed to open in case of overvoltage or lightning strike, right ?
But many of the power strips in the home have built-in surge arrestors, with some of them featuring a spark gap in addition to the usual MOVs.
Could it be because of the surge arrestors that the main breaker popped ?
We had a similar event at the family cottage a few years back. Heard a 'tink' and saw a flash by the electrical panel door simultaneous with the lightning strike, but nothing shut down, no breaker was tripped, and no signs of scorching at the panel. Total mystery.
That's interesting and just as mysterious as my story.
I did a fair amount of high voltage (0 - 1MV+) protection of instrumentation in a previous life - GDTs, VDRs - even down to fast silicon transient diodes. If you can't stop it at first try to delay it a bit until you can. (Lots of energy in 1nF capacitor at 500kV)
I did wonder if the two 'copper' discs should have been each side of the transient disc such that a small gap would be left to form a crude spark gap. I couldn't tell from the video whether this was a goer.
I think someone else suggested this device would need to be placed after a breaker because the fail mode is often to short.
I was lucky that I was not in power distribution and my requirements were usually only for the instrumentation to survive the occasional breakdown.
Also gas discharge tubes do not respond instantaneously - fast but not immediate. They are good because they can usually handle large currents when triggered but pretty low leakage before. (Also low capacitance compared to semiconductor devices)
I've not seen the GDT in series with a VDR before - interesting.
Really like the Tony's chocolate bars but sharing them is a nightmare.
Sorry for the ramble.
no schematic of the chocolate bar , "ShakingMyHead" :-P
those shims looks suspiciously like end caps for a d cell battery
"D batt caps" exactly what I was thinking.
That little yellow wedge that fell out when you drilled the rivets... it should be what gives the unit a variable gap.
I thought that yellow plastic "wedge" is the DIN rail lock /release clip that fell out. :-)
The copper discs go on either side of the MOV and the spark gap is provided by the outer ring of the disc and free air (so the breakdown voltage depends on local weather conditions). You use it downstream of a fuse or breaker so when the MOV fails into a short as they do, the fuse pops. If this is properly assembled it's an effective if crude protection device for a single-phase single-leg system where the ground is bonded to neutral at the panel.
I'm using a bourns GMOV in one of my designs. They also have an isomov which is similar but I think the GDT is formed between two pieces of MOV material rather than just slapping a traditional MOV disc and GDT together.
Eaton also has similar devices
And here I am watching this during a lightning storm.
About TN-C-S in ovearhead lines: In Hungary we have 2 or 4 wires going from poles to houses(3 phase service is common). The PEN is separated to PE and N at the meter box or the breaker box, where it is mandatory to connect a grounding system with an impedance under 10 Ohms. Ideally it should always be a single digit number. It it easy to get it under 5 Ohms with just 2 3m long electrodes 6m apart. Several decades ago TT systems were common and sockets were sometimes grounded to water pipes.
Those waffles with the caramel are amazing! I love those things. Used to work with someone from the Netherlands and she was a fan of licorice and brought real licorice candies to our meetings. She was also big on the licorice tea which was a bit questionable given licorice can differentially deplete potassium levels.
That Toni's chocolate bar is great. If someone has been an arse with you, they get a little chunk and if they've been nice they get a bigger chunk.
My experience with DIN rail SPDs is they start to conduct at about 50% above their rated voltage so a 600V DC SPD conducts at little over 900V and a 275VAC unit at 600VDC.
I watch the video from my hotel in zambia - nice to hear from the country haha.
I just have vacation here, maybe I should explore a hardware store tomorrow
Cool to hear you are actually there. How is the drought in the area where you currently are. From friends in Zambia I hear it is still very bad. A lot of power cuts due to shortage of hydro power due to having not enough water. You should definitely pop to a hardware store, it is fun. Enjoy your stay!
@@Frankhe78 I was first at Livingstone and currently I am in Lusaka. The drought is very bad the people say, food has gotten expensive because the feed for the animals is more expensive than in the past.
Here in Lusaka we have load shedding every evening, luckily my hotel has solar power off grid and I don't notice it.
@@johan-wh5qt Oh wow, my friends are in Livingstone and they have it bad with constant power cuts, even the city water company was out of electricity so there was no more running water. People have to queue for the supermarket to buy one 25 kg bag of maize flower which is the staple food for the people in Zambia. Limited to only one bag per person due to shortage. Things are not going well at the moment. Here in Europe we have absolutely no reason to complain.
Made for making the consumer believe they have protection, albeit the very minimum. It is akin to selling condoms which 1 in every 7 has a pinhole in it. Why 7 I hear you ask, it was the 5th number that I thought of. Keep safe and well Clive 👍
Ta the video.
Ex Africa semper aliquid novi!
All the best from Namibia.
Out of Africa, always something new. Yes.
@@markiangooley Pliny the Elder could not have provided a better translation.
Lots of useful suggestions so far... adding the minor detail that the failure mode for the varistor ceramic disk can be an explosion. Less likely with a very high but short duration voltage spike, but a sustained over voltage condition will lead to very high current, overheating, and rapid self disassembly. The steel discs might be there to contain the most violent parts of the disintegration.
"Zuikervrij" means sugarfree, and the J is not pronoounced as in the beginning of a word (like "Journal"), but rather the -IJ as a gliding sound, a bit like "-ay" in English, b ut more towards the IPA:[i] open vowel. My two cents as a non-native non-speaker😄of that language (but I know it's reasonably close to Dutch).
The IJ vowel started out as a Y, pronounced as EE as in "sugarfree" in really old Dutch. Some Dutch big city dialects do indeed pronounce it close to AY which makes some people's ears bleed. The correct modern pronunciation is unique to Dutch, I think, and a bit closer to EY but still off by a lot. Maybe just type IJ in Google translate and have it pronounce it. IJ is by the way also the name of a lake just above amsterdam. The lake was also called Y a few centuries ago. Quite a few historic waterways in other parts of the country also go by long vowels. Mostly AA or EE.
In Afrikaans the ij in words were replaced with y.
I don't have in faith in lightning arresters. I'll unplug if I hear thunder and see lightning. I would call them surge protectors, because a direct hit could jump the gap. Also, if you use an outside antenna, the lightning can hit it and destroy everything it's connected to. I've had that happen. Fried the cable, antenna, VCR/DVDR combo, the digital tv converter box and the TV. But, it was plugged in to the power receptacles, too. I saw the lightning shoot sparks out of my tv.
Well, a SPD (surge protection device) is only designed to dissipate transient voltage surges due to grid overvoltage or indirect lightning strikes. An additional spark gap can dissipate higher voltages, but theres no device that would protect from a direct lightning strike. A lighning rod on the roof can redirect the current, but this stil causes indirect overvoltage. The best protection is a good type I SPD (MOV + spark gap) and lightning rods on a larger house in your neighbourhood (You dont want to be the one with the lightning rod).
For anttena and data lines, there are special SPDs too, but again they will only protect from overvoltage or induced current from a nearby lightning, not a direct hit.
A fallen line from a 11kV overhead line does enough damage, let alone a direct lightning strike...
Had something similar a year and half or so ago. Coming back home, last few meters, I hear and see a flash instantly. As if I had just avoided lighting striking my damn head by the sheer fact there were buildings around, coming home I see that my living room TV is dead, so is the cable box that killed it, and the freaking Nintendo Switch dock as well that was plugged into the HDMI.
Nothing else failed here, but that one cable TV box that was on the 1st step on that coax before the Internet/phone modem (that one has another splitter down the line, which likely saved it) died and took everything remotely related to it's HDMI together. Freakin thank you cable TV provider...
Antennas should be always connected to grounding blocks. Preferably with surge protectors/arrestors at both ends of the coax or other line.
If the coax is disconnected on the inside side, lightning may find a connection to ground via an unpredictable route, via some other appliance or a human for example.
Proper bonding allows for a safer more direct path for lightning and ground.
I’d be both terrified and mesmerised to have an indoor cumulonimbus cloud spark up a storm… a dehumidifier may be in order…
Thanks Clive.
I've seen Disks like those, in stacks of 4 or 5, but I don't remember where.
Being one of the RF crowd, it would have been a refit of a Telephone Exchange, or a Television/ Radio Station demolition.
I'm really good at breaking stuff...😉
They're used in stacks inside overhead line lightning arrestors.
The combined gdt mov is good because they complement the behavior of one another.
MOVs clamp by reaching their break over voltage at which point a pseudo diode breakdown starts to occur and the resistance drops. But the clamping voltage is always above the operating voltage. But they always have finite resistance and have a leakage current.
GDTs, rely on dielectric breakdown of gas between two plates at which point it becomes basically a short circuit. These devices clamp at some minimum holdover voltage much lower than their nominal rating set by the physical parameters of the device (maybe 100V for example). Because of this they will blow themselves up without current limiting in unlimited power scenarios
So what you do is put a GDT on your MOV because the GDT has no leakage current during normal operation saving power. In surge clamping the GDT breaks down and the MOV sees the full voltage and begins to conduct. Once offensive input reaches below roughly Vmov+Vholdover it can no longer sustain the current necessary to produce an arc in the gas.
African Lightning Detector?! I've now given my glasses a much needed clean.
GDTs are usually only involved in SPDs where the earthing system impedance / distance is high enough, for example in a TN-C / TN-C-S setup the N/E linkage is more than 10 wire meters away from the SPD. Clamp phase to neutral with a MOV and then neutral to earth with a GDT. The GDT prevents continual leakage current onto the earthing system. If the SPD is closer to the N/E link clamping neutral to earth with a GDT is pointless so the GDT is omitted.
From What I Can Tell This Was Made By CBI (Circuit Breaker Industries) Which Is A South African Company, They Are A Well Known And Trusted Company In South Africa And There Products Are Extremely Good Quality And Reliable, I Believe That This Is Either An Older Protector Or A Clone Of A CBI Product As They Do Not Use Those Screws Nor Connectors At The Top And Bottom.
Amazing Video Regardless Clive!
There is no guarantee that this is a 'gin you wine' unit. There is a chance that it could be a Chinese clone / counterfeit.
@@Frankhe78 Most Definitely A Chinese Clone
@@redneck-ryan That is also my feeling.
Yes it looks like they took the CBI samite breaker type and made a cheap clone. The CBI surge arrestor comes with the indication if it is still functional.
It's so hot here now that if I open a chocolate like you did in the video by the time you broke a piece it would have been more liquid than solid.
Hmm. If those two springy plates are magnetic, perhaps they are bimetallic? And once the MOV gets hot they pop and essentiallt crush it, making it a dead short? I was hoping you would try to heat the coppery things up to see if they respond to heat.
If the center of the shims is lower than the outer and that dark ring around the varistor is an insulator then maybe there's actually a small air gap there, but if that's the case I think each steel shim should be on each side of the varistor, unless they designed it to use the same parts to make arrestors for different voltages by swapping the position of the shims, like one way for line to neutral and the other way for line to line.
Really interesting , thank you for sharing this video
6:11 this is a technical data sheet
10:13 this is someone barely proficient in Microsoft Word 2004
I think the metal-oxide varistor should be in between the copper-plated steel disks. Then there'd be a spark gap between the rims of the disks , around the circumference of the MOV. Spark distance the thickness of the MOV plus a bit. That would also convert the linear contact point of the brass spring contacts into a nice gentle ring contact on the MOV.
Stroopwafels sounds like Scabwaffles in my language.
love how you pronounce my language Clive :) the IJ is one sign and sounds a bit like Y
I have once found those Tony's weird chocolates here - not bad, at least the salted variety. And no, I'm not saying they are unobtainable or even necessarily rare here, but I don't see them very often, which may be partially due to my inattention.
Chocolate 🍫 for breakfast. Great minds think alike. I am munching on Jacquot Dark Chocolate from Dollarama.
"One moment pleeeeez" 🤣🤣🤣🤣
Good video Clive of course.
The worst locations in the world for lightning (irrespective of human infrastructure) are south east Asia and central Africa. So even if their country’s standards are low they have lot more lightning than Europe and the like.
Probably phosphor bronze springy clips. I am surprised that the MOV was not between those copper plated pieces to allow more uniform current distribution. This would leave a spark gap in parallel with the MOV around the edge...
I don't think it would take much to protect you, as in my 64years walking this planet I've never encountered any indoor lightning. 😊
251 means 25 with 1 zero, and I think it's the nominal voltage where it's guaranteed not to turn on.
I use Eaton brand ones here in Nova Scotia. And they work! I know first hand lol
Wouldn't need a strike on the line to cause a surge, a lightning strike close to the line could still cause surges due to the magnetic field cutting across the overhead lines.
The roof being neutral earthed may simply be a precaution against the overhead wiring falling on the roof or the means of anchoring the overhead wiring to the building becoming live. Such items can become live indefinitely without the neutral earthing, just waiting for someone to get themselves between it and the physical ground. Lean a ladder on the roof and you are dead more or less. Of course, this assumes fuses or like upstream in the network which there probably is even if it is only on the primary side of the transformer.
Anchoring equipment (P.O.A.) is often neutral earthed in Australia, varies based on the age of the installation and which state / territory it's in.
Dutchie here. That's indeed the most popular brand of chocolate in the Netherlands. It was created by Teun van de Keuken, an investigative journalist. He wanted to make a chocolate brand that was completely slave free start to end after doing a story on chocolate production in the program _Keuringsdienst van Waarde._ He was fined afterwards because you're not supposed to advertise products on public television, let alone your own. But it garnered a lot of support and sympathy because the company genuinely was trying to make a change, it wasn't just buzzwords and marketing. All ingredients are traceable. The uneven division symbolizes the income inequality in the normal supply chains.
No it's not. It's overpriced commercial bs.
I'm not sure it's the most popular brand, but it's indeed a well known one.
@@mjouwbuis because it's a marketing brand it's not about real chocolate.
Maybe the MOV was supposed to go between the two copper-ish shims. Then a large strike could arc between them bypassing the soon to be smoking MOV. ?????????
Can't really test it, you don't get African Lighting in the IoM.
More transient stuff please.
Thanks. I've a few surge arrestor videos.
Thank you, keep working.
Scary the over voltage module does not have over current or over temp protection. I expect much excitement if it fails.
Because it is SUPPOSED to trip the circuit breaker on the feeder to isolate the installation. The voltage limit function is only supposed to last long enough for the breaker to trip.
Lightning is jumping an air gap often miles long. I don't think anything that fits inside a house is going to do jack squat to stop it. :\
"I don't think anything that fits inside a house is going to do jack squat" No. But there are near-misses. Electricity does not 'take the shortest path', it takes ALL paths; more on the better paths, less on the long/skinny paths.
We once had a huge tree hit, can't stop that many-thousands-Volt strike. We also had fried modems and microwave-brain every year, hundreds-Volt side-strokes from a main stroke a ways away. Little MOVs and similar greatly reduce damage from induced current.
It also seems wise to have layers. I have massive dirt-grounding along my overhead line and underground feeder. I have a big MOV unit in the main breaker box. And I have "surge strips" on any precious load.
You said gas discharge tube.
Now I wanna see it light up 😂
Thanks
That's more than what I actually payed for that device when I purchased it in Zambia. It was ridiculously inexpensive, but than, you get what you pay for.
I think that black device was assembled incorrectly, I think that there should have been one of those copper plated discs either side of the ceramic disc so that an extremely high voltage would jump from one to the other the two discs forming the spark gap.
We had a few of those installed at some point and didn't trust them. Mostly, here in South Africa , strict on code and pedantic about safety, we prefer the GE or ABB or such brands. I imagine north of our border, some places dont have access to those brands and have to settle for whatever is available. Also, relying a lot on the surge arrestors mounted on the pole transformers which you never really know if they are still viable or not. 😅Was a bit shocked to see what's inside the arrestor. Thanks Clive
Guess I won't need one of those. We don't get African lightning where I live. :)
Branching out into confectionery analysis now, are you? A second channel, maybe? Sweet!
As a Dutch person i still find it super interesting how African people also speak Dutch but slightly different. It's kinda the same as UK English and the world language English.
Some duch words mean the exact same in Africa and vice versa.
Very very interesting.
Africa is a continent and the only place where people talk similar to Dutch is in South Africa
@powertechnical incorrect, I know friends who don't live in south Africa who use similar words.
@@-never-gonna-give-you-up- I am sure Africa is a continent 😬 Which Dutch words are you referring to? Many words are loan words
@powertechnical oh, no you are correct with the continent but not so much with the dutch similarities only being noticeable in Sout Africa.
A lot of words are indeed loan words but there are quite some words
Here are some words that are not bound to the south.
Vriend (Friend)
Koffie (Coffee)
Kind (Child)
Huis (House)
Water (Water)
Meneer (Sir/Mr)
And there are lots more that actually mean the exact same in both languages. But those up here are specifically not bound to the South.
Sure there are much more words that are the same in the south but you'd be surprised how many are not bound to the south :)
@@-never-gonna-give-you-up- that is all normal words in the Afrikaans language. Many black people can speak Afrikaans in South Africa and some uses Afrikaans and English words as a substitution if it is considered as better word to describe something such as lekker or braai. In other parts of Africa I think languages such as French and Portuguese had a much bigger impact.
I have seen some words such as piesang, baadjie and baie to be common words used in Afrikaans which comes from Malay. I believe Dutch also adopted some of these words.
For some reason, I'd have thought the GDT would be in parallel with the MOV, rather than in series - such that it would shunt/dissipate a larger portion of the energy around the MOV in a surge event instead of forcing ALL of it to go through both devices...
Copper plated "steel springs" used to maintain a constant tension, that copper alone cannot do. Ron W4BIN
Wait, no leakage testing of the chocolate?!
The GMOV; Different African here, this is for me a dumb idea, but a very common circuit form. The why, is the gas arrestor and Varistor characteistics, the GA is slow and shorts very large currents, and the MOV is nanosecond fast and can only short a few decade Amps. And they put them in series.
A number of devices I work with internationally, have this circuit, and they seldom fail, but the protected circuit does...
Tony's is or was a Dutch company started by a presenter called Teun van de Keuken who presented a Dutch TV program about the food industry. He tried to make 'honest' cocoa chocolate bars but I don't like them. They are way too sugary and lots have weird fillings. He sold the company later on.
The copper plated iron/steel wafers might be used to retain the rigidity since copper is pretty soft.
Just watching you apply the high voltages I can smell the result.