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SPD success stories

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Rumast21

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Anyone have stories about SPDs saving their system? Everyone says use them, but little discussion of success.
 
No lightning strikes but a few times drunks have folded trucks into 33kv power poles along the stretch of road outside my farm and the SPD fitted to our main breaker has tripped, not sure about saving anything but it took me 15minutes to reset out neighbours AC unit because of their lack of spd.
 
ThaiTaffy said:
No lightning strikes but a few times drunks have folded trucks into 33kv power poles along the stretch of road outside my farm and the SPD fitted to our main breaker has tripped, not sure about saving anything but it took me 15minutes to reset out neighbours AC unit because of their lack of spd.
Click to expand...
It's those types of stories that are unexpected and an interesting read
 
During an experiment last month feeding open a neutral voltage into the generator port of my 18Kpv I caused a power surge from unbalanced load on my system leading to upwards of 200 V on one leg supposedly and fried some equipment (LED lighting clock radio refrigerator's condensing fan motor's cap and fuse 3 Battery Minder's and main board in a microwave) I just thought I would share this in this thread because a SPD saved a good portion of my equipment sacrificing it's self in the process.

I know I'm gonna get a bunch of crap about this but that's okay we can all learn from our dumb mistakes right.

20240716_160920.jpg Equipment in background was saved by this device
20240716_161349.jpg20240716_161349.jpg20240716_162109.jpg20240716_162145.jpg
Last picture you can see where low voltage MOVs took the hit
20240716_162203.jpg Microwave transformer definite blown capacitor I suspect more damage haven't got into that one yet.
20240715_150729.jpg20240715_150706.jpg This is how I cause a surge next time I think I'll experiment with a resisted load like a waterheater.

Point to be taken cascading level of protection is very important and surges can come from within the home not just from lighting.

On another note I was impressed with the construction of the Belkin Surge Master II power strip.
 
It's possible you'll find very few "stories of success", because most folks assume an electronic device died from old age or was prematurely faulty, and just throw them away and buy another.

Surge protection is protecting your electronic devices & appliances from a silent killer ... micro-surges from nearly every electronic device in your house, larger surges from a large appliance in your house, and even larger surges from a grid-connection, if you have one. It's a silent killer in that nearly all of electronic devices and appliances are lacking a "I just died from a surge" LED on them. They have to be "autopsied", and hardly anyone will do that (for you).

A direct lightning strike is the 4th kind, and requires a special (very expensive) Lightning Protection System, so I'll leave that out of this discussion.

If you do research on power quality, you'll understand that all 3 of these surge types exist and are well-documented, so the problem is present in your home. It's easy to buy these 3 levels of spd's and get them into your house wiring, and you can then check that problem off of things to worry about. You can have your electrician do this for you, as well.

Hope this helps ...
 
Lightning is weird, took out the audio amplifier on my original taito space Invaders LM377 and a single switch multiplexed input line on a pinball machine but nothing else was affected. Neighbors house some 20 yards further away from the strike lost absolutely everything electrical, tell me mother nature ain't playing us.
 
Can't say I've figured out where this should go.
 

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That is my humorous commentary on lightning protection. It is a ground. I have well over a hundred MOV sitting on the shelf, some the size of hockey pucks. Pretty sure I used to be a sales agent for Delta. Thats been sitting there since before my last lightning strike. I'll get around to it.
 
It did something. Did it save the system? Can't say for sure.

O

Thread 'MidNite SPD before and after'

Thought I'd post something I found today.

Customer called to say thier SunnyBoy inverter hadn't been producing for a few days and the breaker feeding the inverter feeding the was tripped... Uh-oh. I get there and find the Midnite SPD looking like it had some unplanned fun. Pulled it off the circuit feeding the inverter and the SunnyBoy fires right back up.

Shown next to new one for reference.

1676502790765.png
  • Like


1724020716491.png
 
OzSolar said:
It did something. Did it save the system? Can't say for sure.

O

Thread 'MidNite SPD before and after'

Thought I'd post something I found today.

Customer called to say thier SunnyBoy inverter hadn't been producing for a few days and the breaker feeding the inverter feeding the was tripped... Uh-oh. I get there and find the Midnite SPD looking like it had some unplanned fun. Pulled it off the circuit feeding the inverter and the SunnyBoy fires right back up.

Shown next to new one for reference.

1676502790765.png
  • Like


View attachment 237431
Click to expand...
thats what I want to see! after investing into midnite solars owners grand childrens college fund just for SPD's, I want to see them work! (for others of course) :ROFLMAO:
 
Did you take it apart and see the fried electronics?

I never met any piece of electronics that could stand up to a lightning strike, die, then work again..... die, burn open and do nothing - yes- work - no.
 
The clear top is SERIOUSLY connected to the base.

Several times I thought about taking a die grinder to it but each time I did I remembered an acquaintance of an acquaintance.

He darn near lost a his thumb and several other fingers while using a die grinder to separate to steel from aluminum. Countless surgeries, PT, about $40k out pocket plus 3 months off work without pay to try to get 50 cents of aluminum cut off a 5 cent piece of steel. No thanks. He wasn't the smartest guy in the world but I sure learned a lot from him.

Apparently, you've never met a Midnite SPD. LOL Feel free to take up their self healing SPD with Midnite. All I can say it that I've seen it.

Perhaps you could drop "self healing surge protector" into your favorite search engine. Pages of results.

 
robbob2112 said:
Did you take it apart and see the fried electronics?

I never met any piece of electronics that could stand up to a lightning strike, die, then work again..... die, burn open and do nothing - yes- work - no.
Click to expand...
It is my belief after watching vids of people taking a direct strike walking on the street and doesn’t die that Zeus gets to decide when he throws the bolt whether it hurts, kills or destroys …
We have nothing to say or do about it…
Let’s jus say Zues is moody , whimsical and gets to do as he wishes in that moment…

I don’t have any bad things to say about Zeus… he’s a cool guy in my opinion..👍
 
OzSolar said:
It did something. Did it save the system? Can't say for sure.
Click to expand...

This is the problem with many protection devices, you don't know that it's protecting you until the day it doesn't, then maybe you (or your kit) die!

Most of our surge arrestors use MOV (Metal Oxide Varistor) devices https://en.wikipedia.org/wiki/Varistor .

These chaps present a high resistance until the voltage across them reaches their trigger voltage at which point they very rapidly (sub-microsecond) clamp that voltage to a "safe" level thus protecting whatever is downstream from them.

Of course, you don't know that they've actually done anything, they look exactly the same in their "before" and "after" photos.

One thing with MOVs is that they "wear", each time they capture a surge the trigger voltage decreases slightly. Eventually the trigger voltage reaches the operating voltage of your circuit and the beasts turn on, permanently. This is not good as a lot of energy gets dissipated. The result is either that the built-in fuse or thermal protection opens or the beast turns into two connectors and a rather blackened area (fires have been caused!!).

I suspect that the device pictured either suffered a massive surge and suicidally did its job, or it's been quietly absorbing surges over the years and eventually wore to the point that it never turned off.

We've had two experiences where I "know" a device "saved" us.

The first was way back in 2012, not long after we moved into our shiny new home. We took a direct strike to the roof; our steel roof structure is actually a very good ground (measures better than our rod) and the only damage other than very frayed nerves (it was LOUD) was two ridge-tiles and a lump out of Madam's (rather expensive) solid teak barge board. I noticed later that the SPD on our incoming supply was showing the red indicator marked "replace". So, it had evidently done something.

The other more recent incident is solar related.

In 2020, after a night's flash-and-bang we awakened to a rather annoyed beeping from the solar inverter accompanied by the "GFI" and "Alarm" lights. I unplugged one panel string and reset the inverter and it started OK, plugging the string back in got the error again.

OK maybe the damp got into the wiring somewhere, it shouldn't as the connectors are "weatherproof" but it did rain a lot. Insulation test to ground at 250VDC measured zero at the inverter plugs. The same string was 650M at the roof connectors, phew, no mountaineering needed.

The only thing between the roof and the inverter is my DC MCBs and the surge suppression. None of the surge arrestors were showing the red indicator. Wrestled the surge arrestors out of their holders, one read zero at 500V (they are 1000V units), the other was about 800k. The units from the other string read 100 & 125Megs. So, we have MOVs that have expired without going red. I suspect they did actually do their job and absorb some nasties, I also suspect that the inverter leakage detection is a bit enthusiastic.

As noted above, MOVs reduce their threshold voltage as they absorb surges. Eventually the trigger voltage goes below the normal circuit voltage and they stay triggered, get hot and melt the solder on the indicator flag which drops into the window and opens the circuit to the MOV so we don't start any fires.

When the new MOV cartridges arrived, I checked them. One measured 1,700 Megs @ 500V (2,000 Meg range) the other measures open circuit on the same range.

Evidently even the remaining "good" units had done their jobs and degraded somewhat.

Those same units are still doing their thing, I did check them when we replaced the inverter, there is certainly some wear showing but the inverters are not objecting. yet.

EDIT I just counted our SPDs. We have a total of 12 double-pole units of various flavours (mostly on the solar) along with an uncountable number of little ones scattered around the "sensitive" kit.
 
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JRH said:
It is my belief after watching vids of people taking a direct strike walking on the street and doesn’t die that Zeus gets to decide when he throws the bolt whether it hurts, kills or destroys …
We have nothing to say or do about it…
Let’s jus say Zues is moody , whimsical and gets to do as he wishes in that moment…

I don’t have any bad things to say about Zeus… he’s a cool guy in my opinion..👍
Click to expand...
you just trying to butter him up i think!
 
As a solar installer, I have a very high belief in Midnite's SPDs! 10+ years ago whenever there was a lightning storm in the area we would expect to go change a few Magnum inverter circuit boards. (We install a lot of off-grid systems locally for Amish homes. "Amish Electric" we call it. 😁 )

When we started using Midnite SPDs we seriously completely stopped having those "after-the-storm" service calls! Now the only time we have to fix inverters from a lightning strike, is if someone has a very serious, very direct lightning hit! I could probably count on one hand how many inverters I have seen with lightning damage, that had a Midnite SPD!

I should also mention that before using the Midnite SPDs, we were using Delta "cans". Don't bother wasting your time on those. After one strike on a system with a Delta can, we cut open the can. Inside we found the 3 wires (L1, L2 and Ground) just terminated a very short distance from each other inside sand. The sand was baked pretty good from the strike. Basically, in those units, when the voltage potential gets high enough, it jumps the gap to the ground, since that is the most direct route to ground. But these are really not effective in most cases!
 
Cmiller said:
As a solar installer, I have a very high belief in Midnite's SPDs! 10+ years ago whenever there was a lightning storm in the area we would expect to go change a few Magnum inverter circuit boards. (We install a lot of off-grid systems locally for Amish homes. "Amish Electric" we call it. 😁 )

When we started using Midnite SPDs we seriously completely stopped having those "after-the-storm" service calls! Now the only time we have to fix inverters from a lightning strike, is if someone has a very serious, very direct lightning hit! I could probably count on one hand how many inverters I have seen with lightning damage, that had a Midnite SPD!

!
Click to expand...
Boom! this describes me exactly.... one charge circuit card, and one main card. (Plus shipping back and forth to the US from Japan) that is exactly what made me go out and but a lot of midnite SPD's. Shut off all of the lights in the shop at night where the inverters, battereis, and SCS are setup and you can see just from the blue glow of all of the SPD's :p
 
crossy said:
One thing with MOVs is that they "wear", each time they capture a surge the trigger voltage decreases slightly. Eventually the trigger voltage reaches the operating voltage of your circuit and the beasts turn on, permanently. This is not good as a lot of energy gets dissipated. The result is either that the built-in fuse or thermal protection opens or the beast turns into two connectors and a rather blackened area (fires have been caused!!).
Click to expand...

A chart on Phillips SP1, commonly used on lighting.

1724163842725.png
 
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