What causes Voltages to sometimes cycle many times a minute?

[Foozool]

4 hours ago, Crossy said:

 

You may wish to explain how a capacitor can stabilise an AC supply.

 

Oh, and Google "variac" whilst you're at it.

 

 

Capacitor works just like a battery. Depends on working voltage of capacitor it can keep the woltage steady at the time of source voltage drop. 

[Crossy]

 

5 hours ago, Foozool said:

Capacitor works just like a battery. Depends on working voltage of capacitor it can keep the woltage steady at the time of source voltage drop. 

 

Are you suggesting that those of us who have spend upwards of 20k Baht on AVRs could have simply gone to NPE and bought a 200 Baht capacitor?

 

What value of capacitor would you suggest? How would I connect it? A reference to an engineering text would be useful, I have "Electrical Engineering" by Edward Hughes (ISBN-10: 0132060116) to hand, it is the 1979 edition mind but I doubt the laws of physics have changed much since then (yes, I still have my uni. books, "The Art of Electronics" by Horowitz and Hill (ISBN-10: 0521231515) is still a particularly good reference.).

 

Remember, we are talking about stabilising a 220V AC supply capable of providing something like 10kW (50A).

 

We have a saying in the engineering world, "When you are in a hole, stop digging".

 

[Naam]

10 hours ago, billd766 said:

17 hours ago, tryasimight said:

3 phase transformer to single phase...really??

When they built the resort there was no 3 phase available so it was wired up as a single phase. Now it is hooked up to the 3 phase and in turn down to a single phase.

a 3-phase transformer delivers 3-phase via three single phases which can be used by 3-phase gadgets as well as by single phase gadgets. our home has a 3-phase supply but only two gadgets use 3-phase.

 

sounds complicated? not at all!

[Naam]

6 hours ago, Crossy said:

We have a saying in the engineering world, "When you are in a hole, stop digging".

some eggsburts who shout nonsense from back benches are born sore losers 

[Crossy]

For fun, and ignoring the fact that capacitors can't store AC, let's see just how big a capacitor would be needed to bridge a 1 cycle brownout at say 10A load and an acceptable voltage droop of 10V.

 

If my memory is OK:-

 

10 Amps for 0.02 seconds (1 cycle) = 0.2 Coulombs (charge).

 

Assuming a linear voltage decay on the capacitor initially charged to 220V we use 4.5% of the energy stored in discharging by 10V, so the actual total charge needed to be stored is 0.2 / 0.045 Coulombs =  4.44 Coulombs

 

Q (charge) / Voltage = Capacitance so

 

4.44/220 = 0.02 Farads = 20,000 uF

 

A 1uF X rated capacitor is about 32mm x 22mm x 13mm and you would need 20,000 of them. Practical?

 

E & O E. (it has been a very long time)

 

IMPORTANT even if you get all these caps together it won't work anyway because capacitors can't store AC. Actually connecting that across the mains would give you a very satisfactory bang as even at 50Hz a 20,000uF capacitor is pretty close to a dead short.

 

[tryasimight]

On ‎28‎/‎06‎/‎2017 at 10:58 AM, Naam said:

 

 

a 3-phase transformer delivers 3-phase via three single phases which can be used by 3-phase gadgets as well as by single phase gadgets. our home has a 3-phase supply but only two gadgets use 3-phase.

 

sounds complicated? not at all!

Not complicated at all....3 phase to 3 phase with 1 or more phases used. Pretty standard worldwide. But please describe a 3 phase to single phase transformer as the poster suggested.

 

Transformers aren't that complicated.

 

Perhaps a zig zag transformer...not that complicated either? Earthing transformer? reactor?

 

Rectify to DC and then transduce back to single phase AC? 

 

Rectiformers are quite interesting.

 

But I've yet to see a 3 phase to single phase transformer as such.

Edited July 2, 2017 by tryasimight

[tryasimight]

On ‎28‎/‎06‎/‎2017 at 0:45 AM, billd766 said:

 

I guess so.

 

When they built the resort there was no 3 phase available so it was wired up as a single phase. Now it is hooked up to the 3 phase and in turn down to a single phase.

 

How do I know?

 

Simple my mate paid for the place to be built and I have been there quite a few times as it is only about 60 metres away if I go through my neighbours place.

 

Also if the single phase has a power cut, but not the 3 phase, the resort still has power while we don't. If the 3 phase is down, which means the street lights are out, but the single phase stays up, we have power while they don't and the new street lights are out.

 

Must be the Thai 4 phase system then......

[bankruatsteve]

What is the 3-phase to single phase transformer about?  Why would there need to be a transformer for that?

[Crossy]

16 minutes ago, bankruatsteve said:

What is the 3-phase to single phase transformer about?  Why would there need to be a transformer for that?

 

It's actually a single-phase to single-phase, but the HV (25kV) side is connected between two of the HV phases (there's no neutral). The other side is just a bog standard 220V winding.

 

There seems to be the idea that 3-phase and single-phase are different animals, indeed in some countries (the US for example) they are, but in Thailand 3-phase is effectively three single-phase supplies with a shared neutral.

[billd766]

4 hours ago, Crossy said:

 

It's actually a single-phase to single-phase, but the HV (25kV) side is connected between two of the HV phases (there's no neutral). The other side is just a bog standard 220V winding.

 

There seems to be the idea that 3-phase and single-phase are different animals, indeed in some countries (the US for example) they are, but in Thailand 3-phase is effectively three single-phase supplies with a shared neutral.

 

Thank you for that explanation.

 

I am not a sparky but that makes perfect sense to me.

 

The single phase dropped out once again this evening for about 30 minutes.

Edited July 2, 2017 by billd766
Added extra text

[Crossy]

7 hours ago, billd766 said:

The single phase dropped out once again this evening for about 30 minutes.

 

it's quite common (and annoying) for one of the three phases to drop out leaving 30% of single-phase customers without power whilst the rest of the village is just fine.

 

Rest assured the three-phase customers also have a failure, you just may not notice it because the other 60% of their supply is still on.

[carlyai]

It's also quite nifty to have 3 phase, because you can wire lights, air, pumps, fans, tv's onto different phases, so you don't lose everything when you lose 1 phase.
Also, if one of your phases is a bit on the low voltage side, you can rearrange to supply your pumps from a better 220 V.
We have one phase that seems to drop out a lot, and on the low side. I found this out when my pumps, protected by over and under voltage thingy, sometimes wouldn't switch on, so I just swapped to another phase. All sweet.

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[billd766]

5 hours ago, carlyai said:

It's also quite nifty to have 3 phase, because you can wire lights, air, pumps, fans, tv's onto different phases, so you don't lose everything when you lose 1 phase.
Also, if one of your phases is a bit on the low voltage side, you can rearrange to supply your pumps from a better 220 V.
We have one phase that seems to drop out a lot, and on the low side. I found this out when my pumps, protected by over and under voltage thingy, sometimes wouldn't switch on, so I just swapped to another phase. All sweet.

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It most probably is quite nifty to have 3 phase but it was not available when we built the house 13 or so years ago.

 

To convert the house to 3 phase would entail a lot of rewiring, plus I would have to pay for a PEA 3 phase transformer to connect to the overhead power supply.

 

If I should think about a standby generator then it will be more expensive than a single phase model.

 

Though the 3 phase tends to stay up longer than the single phase, the ROI for going to 3 phase really isn't worth it, nor is the disruption of the rewiring of the house.

[gdhm]

Hi, back to my original OP. A few minutes ago the cycling Voltages started again after a pretty stable week between 208V and 218V and no obvious voltage cycling, 

 

Here are the results of ONLY a  15 second period from 14:14:05 to 14:15:10 (5 Jul 2017) NO Air Cons are on in our house.
 

218V - 196V - 218V - 196V - 200V - 192V - 216V

 

*Note*  Had one Air Con been on the above readings would have been approx. 5V lower which would put the lower readings well outside the + or - 10% of 220 V acceptable range. 

 

The situation currently is still ongoing since then for around 5 minutes but since  14:20 (now 14:40)  is cycling a little slower and in a smaller range of mostly of 208V to 216V. Could sudden cycling be an effect of authorities stepping down Volts to cope with demand or maybe transformer (or whatever) struggling to meet demand (load). I ask coz I note the maximum now is 216V (218V before the fluctuations started).

 

This behaviour over months seems far normal to me.

 

[Crossy]

There is evidently a cyclic load somewhere, if it's not in your installation then look for a factory or something similar on the same transformer. A thought, is someone welding nearby, our supply goes all over the place when I'm welding?

 

Of course it could be on the HV side, good luck with finding that.

 

BUT. If it's not causing problems for equipment don't worry.

 

Are you using a digital meter? If so see if you can find a cheap analog one, you may find the the dips are actually a lot lower than your meter is showing which could cause issues and also PEA may be interested in addressing.

 

EDIT A 5V drop on a 5A load (your aircon) is significant. Where are you measuring the voltage? Can you get to the meter terminals (not sealed) and check there. We just need to eliminate your installation before moaning at PEA.

 

[carlyai]

Yes, could be welding. Well thought.
Anyone building a new house or welding near you? Or a tractor fixer shop near by? Those small repair shops usually do a lot of repairing for farmers and have lathes and arc welders on the go at odd times.

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[gdhm]

3 hours ago, Crossy said:

There is evidently a cyclic load somewhere, if it's not in your installation then look for a factory or something similar on the same transformer. A thought, is someone welding nearby, our supply goes all over the place when I'm welding?

 

Of course it could be on the HV side, good luck with finding that.

 

BUT. If it's not causing problems for equipment don't worry.

 

Are you using a digital meter? If so see if you can find a cheap analog one, you may find the the dips are actually a lot lower than your meter is showing which could cause issues and also PEA may be interested in addressing.

 

EDIT A 5V drop on a 5A load (your aircon) is significant. Where are you measuring the voltage? Can you get to the meter terminals (not sealed) and check there. We just need to eliminate your installation before moaning at PEA.

 

4

Hi Crossey, thanks for your input and suggestions

 

 Further up our road someone about 5 years ago built a storage warehouse and as far as I know, that's all it's used for (hate the way people can just put up a commercial build in a residential soi).

Just across our soi (one house further down) the son opened a small "home shop" Motorbike repair business (real racket when he is testing their engines as he rev tests or goes up and down the soi). 

When we had out last power cut his place was NOT affected so even though on same transformer he must be on a different power line. I don't know if that exonerates him as a possibility for the cycling.   Even further down the soi there's a small place that washes stage costumes (we often see dancing costumes hanging out on the fences).  I assume he has a few washing machines.  A little further down on the junction of our soi and another soi, there is another Motor Bike repair shop (a bit busier than the one opposite our house but neither very busy). Both have air compressors for blowing up tyres but I cannot think they are the cause as only on a few seconds at a time.  I have no idea if either having welding equipment.

 

I am currently using my APC UPS PowerChute software which reports voltages constantly and it is within 1 Volts (or same) as my old, and still used Digital Multimeter.

 

What in my house wiring could cause Voltage to drop 5Vs when switching on an Air Con? 

The wiring is only 10 years old and I had no issues for several years after the PEA added the extra line for BUT I BELIEVE Air Cons would still lower the voltages, water heaters do as well (anything with high wattage). Just tested 2000W iron seems to drop Volts around 10 -12V (Water heater more). Of course when the extra line was providing 230 -235V most of the time (without Air Cons on, and never below 212V with 2 Aircon on at night. Certainly, extra loads from others who have been added to our line or increased their demands have reduced the 230-235V in our house to an absolute maximum of 222V usually common max is 218V (with Air Cons OFF on low peak weekday daytime periods.

 

OK Crossy, I have just tested outside as suggested and ran my multimeter across my house's Roadside Meter terminals that cables go to my house from (not cable terminals going into the meter (I assumed either were OK for test). I had my son plug in and unplug our 2000W Iron from a nearby power socket in our garden. I can confirm when he plugged in the iron there was a drop of 8-10V and when he unplugged it increased by a similar amount.  Hopefully, this confirms the Voltage drop in the power lines to our house (and not an issue inside) and if so, that is what I expected because the cycling and sometimes sudden drop and a short while later increase by similar amount has always suggested to me someone's Air Con on my power line has just kicked in and later off when temp reached. Additionally, ups and downs (not cyclic ones) occur when our home has no variable electrical usage with no Air cons, water heaters, iron or washing machine running.  I accept the fridge freezer and freezer could be involved but their activity never changes.  I personally am convinced the Powerlines/transformer is operating at near total capacity and any biggish lad appliances being engaged has an immediate hit. If any of my logic is flawed Crossey please tell me is flawed in this para please tell me.

 

Many Thanks

 

 

 

 

 

 

[gdhm]

25 minutes ago, carlyai said:

Yes, could be welding. Well thought.
Anyone building a new house or welding near you? Or a tractor fixer shop near by? Those small repair shops usually do a lot of repairing for farmers and have lathes and arc welders on the go at odd times.

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2

 

 

Thanks carlyai, 

 

Although in city suburbs so farming equipment unlikely, welding equipment seems a good suspect and I had not realised these could have this effect. They would also explain inconsistent occurrences (sometimes days or more apart) and length of each period  Even we have had people come to our house to weld gates and drainpipes etc.

 

Kind regards

 

[carlyai]

My stabilised gets all excited when welding around the place. You can hear it hunting up and down.

As you're probably aware, when they arc weld here they they fiddle around with up to 5 small strikes of about 1 sec or less, then draw the arc for about 2 secs, then off for about 2 secs then on again. If they don't break the arc they blow holes in the metal or the leads catch on fire.

 

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[gdhm]

22 minutes ago, carlyai said:

My stabilised gets all excited when welding around the place. You can hear it hunting up and down.

As you're probably aware, when they arc weld here they they fiddle around with up to 5 small strikes of about 1 sec or less, then draw the arc for about 2 secs, then off for about 2 secs then on again. If they don't break the arc they blow holes in the metal or the leads catch on fire.

 

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No not aware as I have never used or personally worked with welding equipment, so thanks for the explanation 

 

 

 

3

 

[RichCor]

A Cautionary Tail...

 

Last year we had the roof replaced. Lots and lots of arc welding as we had to replace whatever dust was holding the old roof up and metal beams put in place. 

 

Months later we started having power issues. Voltage drops and short outages. As we're about 75 meters from the nearest neighbors, I can't tell if it's a transformer issue, or just a drop coupling going bad. When I go out to check who else has lost power, it's inconclusive and the power's back on at the house anyway. But the voltage fluctuations continue, and the outages last a bit longer each time. 

 

Then I notice a small 'nick' in the covering of "Al" neutral incomer wire near the CU. Every time I notice it, the wire appears to be even more 'bent', showing just a bit more metal, from the last time I looked at it. I tell myself I really should tape it up but I DON'T like to touch live incomers. The wire still looks solid, tapped it with a stick to verify. Seems solid and no flickering lights. I'm just getting old.  

 

A few more months go by and then a long outage. I'm beginning to wonder it there's something up with this wire and the odd 'bend'. Hit it with a stick again and the power returns. Odd coincidence? No sparks, not even a noise. A few more days and the odd little bend starts taking on the shape of a 'dog leg' and when the power goes out I can hit is with a stick and it comes back. This has to be 'it'. Really?

 

I get an village 'electrician' to come over and pull enough slack line out or the ceiling to clip the line and reconnect to the CU. 

 

Inspecting the clipped section of the 'Al' incomer cable close up, the jacket is melted and the strands either 'fused' apart or melted. I've only ever seen this effect with very-high voltage power supplies, not 220v. But then I'm not used to using Aluminium. 

[Crossy]

12 hours ago, gdhm said:

I personally am convinced the Powerlines/transformer is operating at near total capacity and any biggish lad appliances being engaged has an immediate hit.

 

Your tests with the iron and measurements at the meter pretty much exonerate your internal wiring, which is good, no fizzing breaks like RichCor had (could still be a poor connection on the dropper to the meter).

 

As to where to go now. It may be worth talking to PEA but in reality they're only really interested if the the supply is outside the limits (or off) for long periods. They may change you to an alternate phase (an easy change) to keep you quiet, but, of course, that phase may be worse.

 

The volt-drop on load may be a better route to take with PEA, check and record the drop with about 5kW (kettle and water heater) and take that result to them, assuming you have a 15/45 meter that should be more than capable of 20A or so.

 

You could live with it as a fact of living in sunny Thailand or get an AVR, but I'm not sure it would react fast enough.

 

EDIT Just did a quick test with our 6kW (27A) water heater, supply at the main breaker (where we have a digital voltmeter) dropped from 217V to 207V, with a barely noticeable flicker of the CFL light in the bathroom.

 

EDIT 2 Nearly 4V of the 10v drop seen in my test is accounted for by the 120m (60 each way) of 16mm2 running from our meter to the distribution board where the voltmeter lives. So our from at the meter on a 27A load is 6V, quite acceptable.

 

[carlyai]

As always, good one Crossy. As I said, my AVR reacts to arc welding. It did not react to large base notes from a band playing down the road, but the LED lights on that phase dipped in time with the music. I suppose that could raise another question: are you near a music shop or Temple?

 

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[Ace of Pop]

There is evidently a cyclic load somewhere, if it's not in your installation then look for a factory or something similar on the same transformer. A thought, is someone welding nearby, our supply goes all over the place when I'm welding?
 
Of course it could be on the HV side, good luck with finding that.
 
BUT. If it's not causing problems for equipment don't worry.
 
Are you using a digital meter? If so see if you can find a cheap analog one, you may find the the dips are actually a lot lower than your meter is showing which could cause issues and also PEA may be interested in addressing.
 
EDIT A 5V drop on a 5A load (your aircon) is significant. Where are you measuring the voltage? Can you get to the meter terminals (not sealed) and check there. We just need to eliminate your installation before moaning at PEA.
 

We have 4 Aircons and aHeavy Welder.
An Egat Chap got us a 3 phase meter ,and put much thicker cable the house 27 years ago ,we don't weld now, when we did the Aircons cut off, or slowed a bit.. Thesedays only prob is dimming caused when the big Wat sells the juice for Amplified Festivals. EGAT Chaps and PEA are most helpful iv found Even found us A team to do a total re wire last year.Cant be too safe with Electric.??


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[gdhm]

9 hours ago, Crossy said:

 

Your tests with the iron and measurements at the meter pretty much exonerate your internal wiring, which is good, no fizzing breaks like RichCor had (could still be a poor connection on the dropper to the meter).

 

As to where to go now. It may be worth talking to PEA but in reality they're only really interested if the the supply is outside the limits (or off) for long periods. They may change you to an alternate phase (an easy change) to keep you quiet, but, of course, that phase may be worse.

 

The volt-drop on load may be a better route to take with PEA, check and record the drop with about 5kW (kettle and water heater) and take that result to them, assuming you have a 15/45 meter that should be more than capable of 20A or so.

 

You could live with it as a fact of living in sunny Thailand or get an AVR, but I'm not sure it would react fast enough.

 

EDIT Just did a quick test with our 6kW (27A) water heater, supply at the main breaker (where we have a digital voltmeter) dropped from 217V to 207V, with a barely noticeable flicker of the CFL light in the bathroom.

 

EDIT 2 Nearly 4V of the 10v drop seen in my test is accounted for by the 120m (60 each way) of 16mm2 running from our meter to the distribution board where the voltmeter lives. So our from at the meter on a 27A load is 6V, quite acceptable.

 

My meter is a Single Phase  2 -wire,  220V,  30 (100) A meter and it connects to 2 consumer units. PEA told to fit a thicker gauge cable than normally used on lesser A meter systems, to run from Meter to our house to cater for the Meter being 30A and our anticipated usage (min/max range mostly 700 to1050 per month depending upon monthly heat and Air Con usage) 

 

I would estimate our meter across soi to our consumer units would be approx. 35m to 40m long (not sure if relevant).

 

Normally only Air Cons kicking in/off seem to make a noticeable flicker on the lights. I sometimes am suspicious our Microwave  (using  850W) cycles fan speeds slightly.

 

I feel based on all you and others have said that contacting PEA at this stage would probably be unproductive. I will consider doing so if things worsen and Voltage levels more consistently fall below and stay beneath acceptable 10% drop range from 220V at night (currently they do not).  As you said Crossey, initially if they do anything they may decide to switch my connection to a different line, which then would be a case of Russian Roulette whether better or "jumping out of the frying pan into the fire" so to speak.

 

My only concern is if the water pump gets too low Voltage because of all our appliances we know it does not like sustained low level approaching 180V. I also know Air Cons and Fridge/Freezer Compressors do not like low voltages.

However I feel currently most of the time my lows are not less than 200V usually and my PCs UPS kicks in if there is a drop below 175V and that has not happened since 25/07/2017 at that level. 185V at night did result in several kick-ins most nights and so did 180V  to lesser degrees. (I hasten to add before our 2 bedroom Air Cons were on (but to be fair sometimes the PC room Air Con WAS being used at the time) . It set to Low sensitivity which is not APC's recommendation for PCs  (which would be High or Medium) but if on those sensitivities there are too many interventions in early to mid-evenings in Hot or Monsoon seasons.

 

I still possess my readings that I went to PEA with, back in 2008, so I can easily see if things start to close in on those levels at some time in the future.  Personally, I think it is only a matter of time as new homes may be added to my line (or if my line is better than the others in the soi houses may be transferred to balance the lines loads.

 

Thanks for all the advice from you and others.

Kind regards

 

 

 

 

[Litlos]

On 6/28/2017 at 1:50 AM, Crossy said:

 

What value of capacitor would you suggest? How would I connect it? A reference to an engineering text would be useful, I have "Electrical Engineering" by Edward Hughes (ISBN-10: 0132060116) to hand, it is the 1979 edition mind but I doubt the laws of physics have changed much since then (yes, I still have my uni. books, "The Art of Electronics" by Horowitz and Hill (ISBN-10: 0521231515) is still a particularly good reference.).

 

 

That is interesting as I am pretty sure I have those two texts stored away somewhere from my days of obtaining a certificate in Electronic Engineering in Australia.  Probably explainable by 70% of the course being the same for the electrical/electronic streams and the senior lecturer being an English migrant.  From memory the Hughes book was particularly good reference material.  Might have to look for it when I am back that way as I seem to be getting involved in more of the power generation/distribution side of things at the moment.

 

For OP- Do you have any inverter type air conditioners installed?  We have a lot of inverters at work and they can really mess with our power supply if they start acting up.  If you do have inverter type AC's might be worthwhile switching off and see if the voltage stabilises.

 

Cheers

[gdhm]

Today Fri 7 June '17 at 11:48 AM, I experienced two massive cycles in a 5 min period (nothing notable in the 20 mins since). Our Voltage during that period ranged between 216V to 220V (mostly on 218V) which is fine. Something, however, during that 5 min period made the fan next to me slow right down for a moment and although I did not catch the first Voltage drop reading, I did just catch the second one a few mins later, which was ONLY 202V. Can anybody tell me what electrical item could draw a massive 16V in one go, lasting no more than a second? 

 

I am beginning to think I need to check out that warehouse at end of the rod that is "only used for storage" and its the only thing I can think of between our transformer and end of our soi that could use electrical equipment unknown to other in the sois  and its main tall doors are always closed which may mean it is only used for storage BUT a business could be easily running from it.  I have asked my wife to ask her friend who lives 2 houses from it if she has noticed anything or heard electrical equipment being used.  Not sure if she is on our line but IF it would be interesting if she does her heavy sounding electrical equipment being used if her fans slow at the same time being used.

 

Wish I knew the Thai and/or  City laws here about warehouses being erected in a residential soi and if permitted if there are any usage restrictions. Currently, we and I assume others in our soi have no idea if dangerous or combustible stuff is stored there as well as safe stuff.

 

Thanks

 

 

[gdhm]

13 hours ago, Litlos said:

EXTRACT

For OP- Do you have any inverter type air conditioners installed?  We have a lot of inverters at work and they can really mess with our power supply if they start acting up.  If you do have inverter type AC's might be worthwhile switching off and see if the voltage stabilises.

 

Cheers

1

Thanks for question and info.  No, our 10 - 12 years old Panasonic Air Cons are the older NON Inverter type (still using the older type of gas that new Air Cons no longer use).

[RichCor]

2 hours ago, gdhm said:

Can anybody tell me what electrical item could draw a massive 16V in one go, lasting no more than a second? 

Most any starting motor.

If you have longer power draws, those might indicate a seizing motor or one with a failing starting cap somewhere on the line.

 

Outside of some device drawing down the voltage, I'd also suggest doing a 'walking' visual inspection of the entire line from the transformer to your CU and note any connection points.

 

Oh no, another story:

When I was doing a meditation stay in Myanmar, the housing units each had two stories with an electrical phase feeding each floor separately. The upper floor was reserved for visiting Monks and has a washing machine and a on-demand water heater. Neither was working. Curious, I started diagnostics with only a voltage pen in hand. Voltage good. But engaging either large appliance and the power would go out. I doubted *both* where in a fault state, so started visually tracing back the lines and eventually found a very rusted out glass fuse connection outside. Swapping the glass fuses between circuits allowed the appliances to function, but any heavy draw on the rusted fuse caused that circuit to brown out. I notified the staff, but they said no-one could fix it. So I used that as my meditation muse for the next week.

 

tl;dr  --  look for corrosion.    

[gdhm]

Thanks RichCor. It's extremely difficult to follow the powerlines line because there are so many cables in our soi and they do not tend to follow the same height connection on each post, making it even more difficult to follow. At the road juncture where our soi meets another soi. The mess of cables is absolutely unbelievable (maybe not here in LOS ) Sun does not help either.