SPD what does the team think?

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ericmark
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SPD what does the team think?

Post by ericmark »

There seems to have been a lot said about SPD, even to point of giving a code C2 when missing, yet others seem to think not required.

I don't have latest edition of BS 7671 but am told single occupancy homes do not need SPD fitting in them, not sure what single occupancy is? This house old garage turned into granny flat, no used as such, but does the house still come under that rule? same with semi-detached houses.

But the big issue seems to be spikes taking out electronic equipment where there is no transformer before the electronics, i.e. switch mode power supplies, LED lights, smoke detectors, PEN loss detectors used with EV charging, solar panels, fire alarms and smoke alarms, and emergency lights.

In other words damage to safety equipment due to a surge.

On my old fusebox CU the SPD has no MCB, latter versions there is a MCB before the device, seems wrong, as an MCB has some resistance so the device will not work as well, when I bought the board was asked if I wanted it, they offered to remove it, but for £30 may as well have it. I have lost 2 LED lamps in this house, one I know was dry joint as I corrected it and put back into service.

So have you got a SPD fitted? And how many LED bulbs have you lost? And where you live
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seems some areas have more of a problem to others.

And what are your thoughts about the device.
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SPD what does the team think?

Post by Neelix »

The SPD is simply the reflection that manufacturers have too much influence over the regulations.

BS 7671 writers want to issue updates every 3 years. There aren’t enough real changes, so things like SPDs get added, along with really poorly written regulations.

Just wait to see AMD 2 coming up ….. the IET haven’t disclosed the final content, nor when it’s going to be released.

Talk about a farce in the making

I’ve just had enough of the muppets who write and approve the regs

Then there are the increasing numbers of DIYers and Bob the builders who don’t give a toss about the regs

At a time when the regs need to be simplified and written clearer, they do the absolute opposite

I’m near to the point where I’ll throw in my towel
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SPD what does the team think?

Post by kellys_eye »

I would imagine that SPD might become 'essential' if we're going to have intermittent supplies and/or fluctuations due to over-reliance on green sources of energy?

But most well-designed equipment has either filtering or other forms of protection built-in that can cope with 'most' problems.
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Post by Someone-Else »

Correct me if I am wrong, but an SPD is just a MOV (maybe two or three)
If this is true then I think they are just a rip off.

For those that do not know an MOV is Metal Oxide Varistor. It is mounted across L-N But you can also have them L-E, E-N to be sure. If they detect a mains spike the resistance of the MOV drops to an almost dead short killing the spike. They work faster than you can blink, they are self-sacrificing and the cost.................one costs less than 20p
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SPD what does the team think?

Post by ericmark »

This is rather long, some people seem to think lack of SPD in some circumstances should get code 2 with a EICR. I must admit I was of same option as @Neelix but after watching now not so sure.

I have a SPD and I have only had one LED fail, but I read about people who had loads of LED bulbs fail, so maybe lack of SPD is cause.
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SPD what does the team think?

Post by kellys_eye »

ericmark wrote: Sat Nov 20, 2021 12:28 am who had loads of LED bulbs fail, so maybe lack of SPD is cause.
That's why we invented filament bulbs!
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SPD what does the team think?

Post by Neelix »

It’s the cheap sourced LED bulbs which fail …… buy branded and the problems go away
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SPD what does the team think?

Post by OnlyMe »

Neelix wrote: Fri Nov 19, 2021 2:04 pm The SPD is simply the reflection that manufacturers have too much influence over the regulations.

BS 7671 writers want to issue updates every 3 years. There aren’t enough real changes, so things like SPDs get added, along with really poorly written regulations.

Just wait to see AMD 2 coming up ….. the IET haven’t disclosed the final content, nor when it’s going to be released.

Talk about a farce in the making

I’ve just had enough of the muppets who write and approve the regs

Then there are the increasing numbers of DIYers and Bob the builders who don’t give a toss about the regs

At a time when the regs need to be simplified and written clearer, they do the absolute opposite

I’m near to the point where I’ll throw in my towel
The draft proposal is on line for AMD 2

AFDD for all socket circuits

Fuc$ing joke.
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SPD what does the team think?

Post by Neelix »

OnlyMe wrote: Sat Nov 20, 2021 6:18 pm
Neelix wrote: Fri Nov 19, 2021 2:04 pm The SPD is simply the reflection that manufacturers have too much influence over the regulations.

BS 7671 writers want to issue updates every 3 years. There aren’t enough real changes, so things like SPDs get added, along with really poorly written regulations.

Just wait to see AMD 2 coming up ….. the IET haven’t disclosed the final content, nor when it’s going to be released.

Talk about a farce in the making

I’ve just had enough of the muppets who write and approve the regs

Then there are the increasing numbers of DIYers and Bob the builders who don’t give a toss about the regs

At a time when the regs need to be simplified and written clearer, they do the absolute opposite

I’m near to the point where I’ll throw in my towel
The draft proposal is on line for AMD 2

AFDD for all socket circuits

Fuc$ing joke.
Actually it’s worse than that. AFDDs on all circuits except lights
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SPD what does the team think?

Post by OnlyMe »

FFS it is all circuits but lighting - cheers pal

SPDs are cheap enough to install than perform a made up calculation to satisfy men in suits.
AFDDs are not worth the money.

Electrical deaths per year went up after part P was introduced.
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SPD what does the team think?

Post by ericmark »

OnlyMe wrote: Sun Nov 21, 2021 8:50 am SPDs are cheap enough to install than perform a made up calculation to satisfy men in suits.
This is why I fitted them, since using FuseBox brand, cheap enough.
IET wbsite wrote:In the previous edition of the IET Wiring Regulations, BS 7671:2008+A3:2015, there was an exception for some domestic dwellings to be excluded from surge protection requirements, for example, if supplied with an underground cable, but this has now been removed and it is now a requirement for all types of premises including single dwelling units. This applies to all new build and properties being rewired.
Seems we have no option with new build.
Neelix wrote: Sat Nov 20, 2021 11:56 am It’s the cheap sourced LED bulbs which fail …… buy branded and the problems go away
That has not been my experience, I had problems with G9 bulbs
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it was the cheap one which cured my problems of flicker, i.e. the big one, which breaks all the rules with no watts or lumen marked on bulb.
kellys_eye wrote: Sat Nov 20, 2021 9:06 am That's why we invented filament bulbs!
That is true, filament bulbs also give off inferred heat so reduce air temperature required to make the room comfortable, so save energy, although not money as electric more expensive than oil or gas. And likely help absorb surges, the same applies to using extra low voltage with a toroidal transformer, the transformer with likely not pass the surge, but could cause a surge, not the case with electronic transformers however.

But the claim seems to be because we use semi-conductors connected direct to mains today, rather than have a transformer first which tended to remove surges, we have more equipment likely to fail because of a surge, (I would have called it a spike rather than surge) and with RCD protection the filters do not connect to earth like they did, so the filters do not protect equipment as well as they did years ago.

Main worry it seems is safety equipment, mains powered smoke detectors for example, seems easy option is use battery powered! But be it the smoke detector, lights, or less important like the TV we clearly don't want to loose them, and with washing machine, freezer, fridge/freezer, TV, etc now being switch mode or inverter powered we have much more equipment both likely to be damaged with a surge, and if damaged likely it put DC on the mains, although the latter really where items generate or have batteries, like solar panels and EV charging.

So we see conflicting reports on if we can use type AC RCD's and need for SPD. Personally I am not sure if we even "Need" a RCD never mind if type AC is good enough, we do see reports like the death of Emma Shaw where we can say a RCD would have saved her, but very few such reports before we had to fit RCD's other than with TT installation, and the loss of a freezer full of food is not funny, more to point is when we don't realise a freezer has part de-frosted, my freezer went bang, so I knew it had failed and when, I had a spare used to brew beer, so turned it on for an hour to cool down before opening the failed freezer door to transfer food, it had clearly failed at end of defrost cycle, so food above the back plate had defrosted, food below plate was OK, but I had thought I had much longer before food defrosted. My new freezers show the highest temperature reached before power returned, but cheaper single phase freezers without inverter drives tend not to have this feature, and once door opened it resets anyway.

So a balance or as we call it today a risk assessment between dangers of having and not having RCD protection. Also financial implications of having or not having or even how many circuits with RCD and SPD use. But in both cases there seems to be a lack and also conflicting data. To the extent of some countries outlawing type AC RCD's.

So we as electricians need to tell the customer you need SPD or RCD or RCBO because other wise this or that may happen, and in real terms we have no idea if this or that can really happen or not. We may watch video by John Ward or Big Clive among others who tell us why, but I watched the John Ward video on type AC and type A RCD's and the way DC was passed through the RCD for test would never happen in real life. Also although we say 40 mS for a RCD to trip, in most cases they trip before we touch anything live, which is likely made live due to water ingress, so even if it took 5 minutes it would still in most cases protect us.

So on RCD's the big question, how many serious injuries or deaths were there in TT installations with type S 100 mA RCD's before the rules asked for 30 mA at 40 mS? Is type A really required? And how much is lost due to surges both before and after SPD were fitted?

If we loose the aerial booster likely it is due to near miss, or a surge, but the SPD in the consumer unit will not stop that, same applies to telecommunication equipment, (phones) they may be damaged, but a SPD in the consumer unit will not help, and since the master socket belongs to OpenReach or Virgin etc, we have no option anyway. Same in a way applies to DNO, if the SPD is with the meter in an outside meter cupboard that is far safer or better place for it to being built into the consumer unit which is normally indoors. So better if built into the smart meter in areas where required, i.e. over head supplies.

But as it stands we as electricians need to tell the customer they need some thing which we are not really sure they need anyway.
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Post by Neelix »

ericmark wrote: Sun Nov 21, 2021 10:56 am But as it stands we as electricians need to tell the customer they need some thing which we are not really sure they need anyway.
Absolutely correct.

Just wait until AMD 2 is released ............. then the fun will start big time.
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Post by ericmark »

Back in 1990 I returned from working in the Falklands for 5 years to hear nothing but "16th edition says". Also to a UK where we had started to use RCD's, and with a son who decided to follow dad and become a radio ham, in his case at 14, I wanted to protect him, so fitted RCD's to my own house, before they were built into consumer units, well before consumer units, still had distribution units then, so I have had RCD protection since around 1992.

Not without problems, lost a freezer or two full of food, but those old RCD's were semi conductor free, so no real worries about spikes damaging the RCD.

Today we have semi-conductors everywhere, and so a spike can take out things we would not have dreamed of being a problem in the past, so I can see the SPD may be even considered as a safety item.

But the word is "MAY" we don't know, we just think it may be. The LED light is the major consideration, to loose a chunk of lighting due to a surge is clearly a problem, but that would involve multiple bulb failures at the same time. I have not seen this.
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Post by Neelix »

The problems with items getting damaged that far too much cheap tat is sold in the uk now.

Built to poor standards and nobody cares:
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Post by ericmark »

Low quality and cheap are not the same. Philips Dubai lamps are it seems good quality, but not available in UK.
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