Inverter blowout.

[DarrenNock]

Good Day,

I have installed an Axpert 5kva inverter with 4x100ah gel batteries with a changeover switch, fuses for the batteries and a 2 breaker for the supply to the inverter at a customer. I got a call from the customer saying the inverter was smoking and this was when there was still normal utility power coming into the customer house. There wasn't a surge from utility either. The supplier has turned around and said it's a 'sudden oveload' and it has burnt the overload protection on the into and is now not will to replace it even though it is still under warranty. 

My question is, If there was a 'sudden oveload' then why did the inverter not alarm for a couple of seconds (as I understand and seen them do) and then switch off to protect itself and the load going into the customers house. 

Your help on this will be greatly appreciated. 

Darren

[Coulomb]

10 hours ago, DarrenNock said:

I have installed an Axpert 5kva inverter with 4x100ah gel batteries

200 Ah is recommended for 5 kW models. I don't immediately see how this would be connected to the overload failure though.

I don't know how robust overload protection is.

[JustinSchoeman]

13 hours ago, DarrenNock said:

The supplier has turned around and said it's a 'sudden oveload' and it has burnt the overload protection

Huh?  The Axperts are marketed as having overload and short circuit protection.  If the overload protection fails, then that is a feature of the inverter, that was sold to you, which has failed.

If the supplier refuses to replace/repair it, then you can try either the small claims court, or the NCC.

Just make sure you have met all the warranty conditions. Many Axpert suppliers have fine print in their conditions stating that you must have SPDs on AC inputs and outputs, or other such junk.  They may try to deny the claim as your installation does not meet the minimum recommended requirements (100Ah instead of 200Ah batteries), but I am not sure a recommendation is a legal limitation (unless such a clause was included in the warranty).

[___]

On 2020/09/04 at 7:53 PM, DarrenNock said:

the inverter was smoking

Something to check: It could be a poor connection or a hot wire that is smoking and not the inverter. As a rule, if electronic components start smoking, things stop working pretty soon after that. If things continue to work, then it's probably a conductor that is smoking. Check all your connections. I've had some cases where I accidentally clamped the tip of the insulation of the cable in the terminal instead of the copper, causing a poor connection, some oxidisation and some generated heat.

[PaulinNorthcliff]

Earlier this year I had a major lightning strike on the koppie across the road from my office. It hit me through the earth and blew EVERYTHING, Main DB, electric fence, cameras, pretty much anything plugged in... also my two (two month old) Kodak 4.6Kw direct inverters (through the connection to mains). Blew them internally beyond repair. Insurance (eventually and reluctantly) replaced everything.

I had a long chat with the technical manager at Segen Solar and the only thing that can apparently arrest a lightning spike coming through the earth cable is a piece of equipment that can sense the impending wave form rise and instantly sever the connection. Ordinary overload protection is too slow.

[___]

1 hour ago, PaulinNorthcliff said:

instantly sever the connection

I would be incredibly impressed with anything that can do that. The trouble with opening a circuit is extinguishing the arc. The arc of lightning.... which has already proven its capabilities just up the cable from here...

I think the best thing I've seen is a type of air-gap arrester used in some security systems. Literally a small array of correctly spaced plates that will arc over at a few thousand volts. Still kills a bunch of stuff, but the stuff furthest away from the arrestor has a slim chance...

[PaulinNorthcliff]

I'll try remember the name of the product again. My mind is a huge pile of unordered factoids. They occasionally pop up at the most inopportune moment. The way the product works (as I alluded to) is by monitoring the waveform of the incoming power and when it identifies a certain pattern of buildup it opens the circuit before the voltage surges.

Malcolm at Segen told me about it.

 

Edited September 7, 2020 by PaulinNorthcliff

[Coulomb]

7 hours ago, PaulinNorthcliff said:

Earlier this year I had a major lightning strike on the koppie across the road from my office. It hit me through the earth and blew EVERYTHING, Main DB, electric fence, cameras, pretty much anything plugged in... also my two (two month old) Kodak 4.6Kw direct inverters (through the connection to mains).

Wow. I used to think that we had strong lightning in Queensland, with some researchers at a local university specialising in it.

But I think South Africa blows us away! 🌩

[PaulinNorthcliff]

11 minutes ago, Coulomb said:

Wow. I used to think that we had strong lightning in Queensland, with some researchers at a local university specialising in it.

But I think South Africa blows us away! 🌩

I sit on a mound of dolorite with thick iron veins running through the rock. One of the highest points in Jhb with crisp, dry air. The lightning here is epic.

[PaulinNorthcliff]

A neighbor tells me that he once had a chunk of  concrete about the size of a 5l paint can lying in the bottom of his pool (with a corresponding hole about a meter below the normal, now drained, water level). It looked for all the world like a cannon had blown a hole in his pool, from inside the earth! Eventually they figured out that there was a major lightning strike on the Berario side of the koppie, and the current had travelled through the ground and decided to pick his steel reinforced concrete pool shell to reappear through.

Bizarre.

I had a tall silky oak in my driveway literally explode a few years ago when it was hit. About 5m off the ground a large junction in the stem blew apart as if someone had strapped ANFO to it. Blew meter-long shards of wood through my tiled roof. Serious stuff.

[Johandup]

The best protection is really a poor municipal reticulation system as it would trip early into a storm. Lol

Surge protection systems can be horrendously expensive or you can go the ACDC way. Which I did. 
My house had 5 scary surges in an hour last season and I came out unscathed But it was a horrible experience which I don’t want to repeat. The first was a flash from the kitchen tap as my helper was walking towards it. Then two loud noises from the db which made me go cold.  The last two were bright flashes hanging in the air 2m high just outside the glass doors where I was sitting. My wife also observed this. First time ever that I’ve seen a thing like this. 
After my borehole got hit last year I upgraded my system with surge suppressors and additional earth spikes of which I have now 6 installed. 
Hopefully this will keep the strikes at bay. 
But living on a koppie with iron inside it is not good news. You really need high lightning rods and a buried copper boundary to contain nature. On the coal mines the surface explosives magazines are protected this way. 
Dolerite is magnetic btw and is magma from the earth’s centre. So it makes an excellent target. It is also very hard and makes up the infamous dykes in a coal mine. 

Edited September 8, 2020 by Johandup

[Johandup]

5 minutes ago, PaulinNorthcliff said:

A neighbor tells me that he once had a chunk of  concrete about the size of a 5l paint can lying in the bottom of his pool (with a corresponding hole about a meter below the normal, now drained, water level). It looked for all the world like a cannon had blown a hole in his pool, from inside the earth! Eventually they figured out that there was a major lightning strike on the Berario side of the koppie, and the current had travelled through the ground and decided to pick his steel reinforced concrete pool shell to reappear through.

Bizarre.

I had a tall silky oak in my driveway literally explode a few years ago when it was hit. About 5m off the ground a large junction in the stem blew apart as if someone had strapped ANFO to it. Blew meter-long shards of wood through my tiled roof. Serious stuff.

When I arrived home in Secunda 33 years back I found my tv scattered across the living room. 
Fortunately my baby daughter and myself had to fetch my wife from hospital at the time it happened. 
She was always fiddling with the tv’s coloured lights. 
This town is infamous for lightning damage. 

[___]

19 hours ago, PaulinNorthcliff said:

when it identifies a certain pattern of buildup

Aaah, so it's pre-emptive, not reactive. I bet it is expensive..

[PaulinNorthcliff]

2 hours ago, plonkster said:

Aaah, so it's pre-emptive, not reactive. I bet it is expensive..

Yep. About 5 or 6K a unit. At the end of the day still cheaper than blown inverters.

[PaulinNorthcliff]

OK. Found the info. The product name is SineTamer. Speak to Marius at Adriatic power 082 889 3663.

 

https://adriaticpower.co.za/sinetamer-electricians/

[Gnome]

3 hours ago, PaulinNorthcliff said:

OK. Found the info. The product name is SineTamer. Speak to Marius at Adriatic power 082 889 3663.

 

https://adriaticpower.co.za/sinetamer-electricians/

I can confidently say this product is snake oil.  There are two types of lighting damage.

Direct strike, which is lighting connecting directly to your electrical supply, which frankly is billion+ volts so there is absolutely nothing that can save you there.  We had one of these when I was a child and the TV, fridge, phone, amplifier etc. literally exploded into pieces from the amount of power.  Forget about protecting against that with electronics, the power coming in was so much it ripped apart the plastic & metal housings throwing things around.  The same can be seen when lighting strikes the ground.  It burns a hole in the ground and rips the ground open.  And soil isn't even a conductor.

Indirect strike, the most common where high voltages flow, typically through an earth wire into the house wiring (due to the high voltage current is flowing through multiple paths including back into the house wiring).

Indirect strike can be protected against by a combination MOVs, GDTs, TSVs and transformers.  But there is no way you can monitor a line for a lighting strike then disconnect.  Current moves at very close to the speed of light.  By the time any software sees the spike it is already moving through.  MOVs, TSVs. GDTs etc. work by clamping at a specific voltage (they have a response time, TSV being the fastest).  These response times don't work on the principle of monitoring, it is an intrinsic property of break-down caused by voltage, thus it can occur at the speed quoted in the datasheets.

So yeah, that sinetamer can help you deal with continuous brown-outs and voltage spike that lasts multiple milliseconds, but lighting doesn't fit into that category.

Also they don't state the terms and conditions in their "warranty".  If you have a R100m piece of equipment connected I guarantee they don't have an insurance policy that will cover that.  That is exactly why surge protectors have very, very strict terms and conditions regarding their warranties.

Edited October 7, 2020 by Gnome

[PaulinNorthcliff]

On 2020/10/07 at 4:06 PM, Gnome said:

I can confidently say this product is snake oil.  There are two types of lighting damage.

Direct strike, which is lighting connecting directly to your electrical supply, which frankly is billion+ volts so there is absolutely nothing that can save you there.  We had one of these when I was a child and the TV, fridge, phone, amplifier etc. literally exploded into pieces from the amount of power.  Forget about protecting against that with electronics, the power coming in was so much it ripped apart the plastic & metal housings throwing things around.  The same can be seen when lighting strikes the ground.  It burns a hole in the ground and rips the ground open.  And soil isn't even a conductor.

Indirect strike, the most common where high voltages flow, typically through an earth wire into the house wiring (due to the high voltage current is flowing through multiple paths including back into the house wiring).

Indirect strike can be protected against by a combination MOVs, GDTs, TSVs and transformers.  But there is no way you can monitor a line for a lighting strike then disconnect.  Current moves at very close to the speed of light.  By the time any software sees the spike it is already moving through.  MOVs, TSVs. GDTs etc. work by clamping at a specific voltage (they have a response time, TSV being the fastest).  These response times don't work on the principle of monitoring, it is an intrinsic property of break-down caused by voltage, thus it can occur at the speed quoted in the datasheets.

So yeah, that sinetamer can help you deal with continuous brown-outs and voltage spike that lasts multiple milliseconds, but lighting doesn't fit into that category.

Also they don't state the terms and conditions in their "warranty".  If you have a R100m piece of equipment connected I guarantee they don't have an insurance policy that will cover that.  That is exactly why surge protectors have very, very strict terms and conditions regarding their warranties.

Can't say. Was recommended to me by Malcolm Koertzen from Segen. They don't supply Sinetamer so would appear to be neutral (groan) in this.

 

[Gnome]

3 hours ago, PaulinNorthcliff said:

Can't say. Was recommended to me by Malcolm Koertzen from Segen. They don't supply Sinetamer so would appear to be neutral (groan) in this.

 

More elegant than me, but the facts are there: https://stormhighway.com/surge_protectors_ups_lightning_protection_myth.php

[PaulinNorthcliff]

5 hours ago, Gnome said:

More elegant than me, but the facts are there: https://stormhighway.com/surge_protectors_ups_lightning_protection_myth.php

OK, so I'm imminently unqualified to enter into a technical discussion on this... but...

As Malcolm explained it to me... the Sinetamer monitors the incoming sine waveform and as soon as the waveform starts to trend upwards (ahead of the coming spike - I'm led to believe that this is measurable) beyond a set parameter, it cuts the link!