What will happen if my SPD activates?
- Thread starter Vicario
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From what (little) I know of these things, my personal answer to those two questions would be "You almost certainly won't know" and "Who knows?" respectively. Others may have more useful answers!
As I repeatedly say, at least from my personal point-of-view I am still looking for the problem (in the real world, not theory) for which these things are an alleged solution
Kind Regards, John
I assumed they eventually change colour and some you then just plug in a new module
If it has some sort of 'indicator' one could do that, but do they all (have indicators)? Even if they do, I would also imagine that it might well be possible, in some circumstances, for them to 'blow up' without the indicator 'indicating'?
Kind Regards, John
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Do you feel that there is a chance they could "Blow up", John.
You won't.
No.
However after 1000s of transients have been absorbed it will be degraded to such an extent that it becomes permanently conductive, it will heat up and melt a fusible link inside which will disconnect the device and show a red indicator in the window. It then needs replacement.
Well, I wasn't necessarily thinking of bangs and smoke, but rather sufficient internal damage to mean that they no longer cable of functioning as intended.
Have we yet seen 'SPD testers' appearing on the scene? (if so, maybe they would represent a solution to the problem of knowing whether a solution to problem which might not significantly exist was still providing that solution satisfactorily?
)Kind Regards, John
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John Ward did a video why here what is in it here
To cut it short what he says is switch mode power supplies and the like have semi conductors before the transformer where in the old days it was after the transformer and the transformer reduced the effect of spikes.
The problem is we are guessing as to if they help or not, we hear some people complain LED lights don't last long, others say they last for ages, in this house I have lost 2 LED lamps in two years, and old house 2 LED in 5 years, and this house has SPD and old house does not.
So at first glance seems they do not help, but son now lives in my old house, and he has last 15 LED lamps, he blames it on cheap toolstation GU10 lamps, but it also could be due to spikes.
Be it a RCBO or a SPD had to say if they pay for themselves, could be luck, or bad luck, or could be the RCBO does not trip as often due to less on each device, and the SPD is stopping spikes.
For the home owner he pays or does not pay for RCBO and SPD and he takes the chance of component failure or freezer failure as a result of not having the extra protection.
Where the problem arises is where one person is paying or not paying for extra protection, and some one else picks up the bill if the protection is not fitted, as with the landlord - tenant situation.
Also if every home has SPD fitted each home will assist in removing the surge, so in a street with all new builds each with SPD one odd home without it is less likely to have a problem to where yours is only home in the street with it fitted.
So if we did a survey of people on here if they have a SPD and if they have lost LED lights for example if may give a warped result. There is an even longer talk here here one point brought up was insurance and it seems some insurances require SPD to be fitted.
It seems however for single dwelling SPD is not required, elsewhere a risk assignment is required if not fitted.
I don't think the insurance issue is there with domestic.
So the big question to me is what must a landlord do, as home owner it is up to me, but as soon as we go landlord tenant then really a different question.
To cut it short what he says is switch mode power supplies and the like have semi conductors before the transformer where in the old days it was after the transformer and the transformer reduced the effect of spikes.
The problem is we are guessing as to if they help or not, we hear some people complain LED lights don't last long, others say they last for ages, in this house I have lost 2 LED lamps in two years, and old house 2 LED in 5 years, and this house has SPD and old house does not.
So at first glance seems they do not help, but son now lives in my old house, and he has last 15 LED lamps, he blames it on cheap toolstation GU10 lamps, but it also could be due to spikes.
Be it a RCBO or a SPD had to say if they pay for themselves, could be luck, or bad luck, or could be the RCBO does not trip as often due to less on each device, and the SPD is stopping spikes.
For the home owner he pays or does not pay for RCBO and SPD and he takes the chance of component failure or freezer failure as a result of not having the extra protection.
Where the problem arises is where one person is paying or not paying for extra protection, and some one else picks up the bill if the protection is not fitted, as with the landlord - tenant situation.
Also if every home has SPD fitted each home will assist in removing the surge, so in a street with all new builds each with SPD one odd home without it is less likely to have a problem to where yours is only home in the street with it fitted.
So if we did a survey of people on here if they have a SPD and if they have lost LED lights for example if may give a warped result. There is an even longer talk here here one point brought up was insurance and it seems some insurances require SPD to be fitted.
It seems however for single dwelling SPD is not required, elsewhere a risk assignment is required if not fitted.
I don't think the insurance issue is there with domestic.
So the big question to me is what must a landlord do, as home owner it is up to me, but as soon as we go landlord tenant then really a different question.
All true, but 'the old days' were a long time ago. Although SMPSUs are undoubtedly proliferating, they have been around for decades, and countless (millions) of them have been around for very many years.
We (at least I) are not only guessing about whether SPDs will 'help', but also about whether the theoretical effects of 'spikes' arev actually mirrored by a significant real-world problem (that needs a 'solution'). As you will be aware, I am personally far from convinced - although I would be happy to change if someone could provide me with some 'convincing evidence'.
I have a lot of respect for flameport. However, as I sometimes point out to him, he seems to have a tendency to assert strongly something as being 'a requirement' on the basis of a theoretical 'problem', without there necessarily being much, if any, evidence that there is, in practice, a significant real-world manifestation of that 'theoretical problem'.
The cheapest serious SPDs seem to be about £30, with some costing well over £100. For (very conservative) 30 million or so electrical installations, in the UK that therefore probably amounts to at least a billion pounds. I personally feel that one probably needs a bit more than theory to justify such a cost.
Kind Regards, John
Kind Regards, John
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I have to agree with you @JohnW2 I watched the video about need for type B RCD and SPD and in both cases not convinced.
However not convinced on the need for all the 30 MPH speed limits either, because some does 80 in a 40 limit and has an accident is not reason why it should be reduced to 30.
But the SPD goes across the supply, so if your neighbour has one, it can also protect you, and if you all have them there will be very few spikes so if required should it be the supply authority or the home owner providing them?
Same goes for earth electrodes, to my mind the DNO with a TN-C-S supply should have enough earth electrodes so even with loss of PEN the voltage variation is within limits.
But where do you draw the line? and if the consumer fits SPD and/or earth electrodes will this mask a fault which otherwise would have been detected?
Some of the devices used today I question about where fitted. For example with an EV charging point on a TN-C-S supply the unit can auto disconnect if the supply voltage falls out of the range of 207 to 253 volt, sounds a good idea, but why only the charging unit? If there is a loss of PEN, then would it not be better to disconnect whole house? The smart meter has a disconnect device built in, so why not have it so with loss of PEN it disconnects whole house?
Talking it to next step, end of supply line could have a wireless link to step down transformer and disconnect whole supply with loss of PEN. Or even better scrap whole idea of TN-C-S.
We could as when the water mains were changed from cast iron and lead to plastic, tell all that TN-C-S supplied are to be made into TT supplies for domestic supply, and all domestic users must have all RCD protection, as the ELI from the supplier can no longer be relied on.
OK most of the losses of PEN are due to copper theft, but not all, the one I was involved in was due to road works, but big question is who is responsible for the quality of the supply?
However not convinced on the need for all the 30 MPH speed limits either, because some does 80 in a 40 limit and has an accident is not reason why it should be reduced to 30.
But the SPD goes across the supply, so if your neighbour has one, it can also protect you, and if you all have them there will be very few spikes so if required should it be the supply authority or the home owner providing them?
Same goes for earth electrodes, to my mind the DNO with a TN-C-S supply should have enough earth electrodes so even with loss of PEN the voltage variation is within limits.
But where do you draw the line? and if the consumer fits SPD and/or earth electrodes will this mask a fault which otherwise would have been detected?
Some of the devices used today I question about where fitted. For example with an EV charging point on a TN-C-S supply the unit can auto disconnect if the supply voltage falls out of the range of 207 to 253 volt, sounds a good idea, but why only the charging unit? If there is a loss of PEN, then would it not be better to disconnect whole house? The smart meter has a disconnect device built in, so why not have it so with loss of PEN it disconnects whole house?
Talking it to next step, end of supply line could have a wireless link to step down transformer and disconnect whole supply with loss of PEN. Or even better scrap whole idea of TN-C-S.
We could as when the water mains were changed from cast iron and lead to plastic, tell all that TN-C-S supplied are to be made into TT supplies for domestic supply, and all domestic users must have all RCD protection, as the ELI from the supplier can no longer be relied on.
OK most of the losses of PEN are due to copper theft, but not all, the one I was involved in was due to road works, but big question is who is responsible for the quality of the supply?
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Every house having an SPD will not have any perceivable effect on surges which appear on the LV ring. Everyone seems to forget transients are high frequency events exacerbated by the parasitics of each LV drop to the house.
Think of it more like an impedance matching problem.
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To forget I need to know in the first place, and unless one has an oscilloscope connected to the supply one really has no idea what transients there are, I think last house had them, as every so often we would get repeated tripping of RCD then it would remain in for a few years, I would assume some one in the street was doing some welding, or a bad connection on the supply some where?
I have SPD in this house, and today lost one LED bulb which could have been a transient, but question is why only one? If on the same day I loose 5 bits of electronic equipment I would say maybe transient caused it. But odd one here and odd one there, seems unlikely caused by transient.
But years ago we have filters on the supply, and these caused a slight leakage to earth, so too many and the RCD would trip, so the filters seem to be used less, so can see how they need replacing by the SPD which is before the RCD.
I have SPD in this house, and today lost one LED bulb which could have been a transient, but question is why only one? If on the same day I loose 5 bits of electronic equipment I would say maybe transient caused it. But odd one here and odd one there, seems unlikely caused by transient.
But years ago we have filters on the supply, and these caused a slight leakage to earth, so too many and the RCD would trip, so the filters seem to be used less, so can see how they need replacing by the SPD which is before the RCD.
It is extremely annoying when an acronym (such as SPD) is posted without any explanation as to that which is meant.
From the context of this thread I have deduced that SPD may mean "Surge Protection Device".
Fortunately, sites such as https://acronyms.thefreedictionary.com/SPD are also of some help in this regard !
From the context of this thread I have deduced that SPD may mean "Surge Protection Device".
Fortunately, sites such as https://acronyms.thefreedictionary.com/SPD are also of some help in this regard !
Unfortunately due to the current Uk regs this term is going to be used a lot from now.
For electrical ones the Definitions are usually in the Uk regs book.
I see your point though, but more when certain posters use a certain few letters instead of typing the words, I recall Bas did it frequently and i often googled it to see what he meant, Ie AIUI and FWIW etc
As has been said, it's unfortunately the case that anyone with an interest in 'electrics' who is appropriately participating in a 'UK Electrics' forum will very soon, if they don't already (which many/most do), know only too well what "SPD" means - and I imagine that the same will become true in your country if/when the "it is technologically possible, so let's make it a requirement" brigade show their faces nearer to your home.
Are you really suggesting that we should stop using abbreviations such as MCB, RCD, RCBO etc, without 'explaining their meaning' every time they are used?
Kind Regards, John
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