Are CU SPD's worth it?

[Gigagator]

Hi all,

I have quite a bit of electrical kit at home that I would be gutted to lose in the event of a mains surge - a high end gaming PC, a server and some old games consoles from my childhood that I would be devastated to lose.

I have a couple of plug in surge protectors like this but I have been wondering lately if an SPD in the consumer unit would be a valuable addition to our installation.
Wouldn't have to panic then when I forget to use the plug in surge suppressors.

Seems like a good idea, but are they reliable and do they offer the same level of protection as one of those plug in ones?

Finally, is the installation of these devices appropriate to be undertaken by a competent DIYer or should I get an electrician out?

For reference, here is the Hager branded CU from 2016 when the house was built:


I assume this would be the correct part for my CU?

Thank you all in advance for the advice. Also keen to hear the opinions of those on here who are sparks by trade.

 

[JohnW2]

I have quite a bit of electrical kit at home that I would be gutted to lose in the event of a mains surge ......... I have a couple of plug in surge protectors like this but I have been wondering lately if an SPD in the consumer unit would be a valuable addition to our installation. Wouldn't have to panic then when I forget to use the plug in surge suppressors. Seems like a good idea, but are they reliable and do they offer the same level of protection as one of those plug in ones?

You'll find very varying opinions about this.

For what it';s worth, it's only a small number of years ago that any mention of 'surge protection devices' (usually plug-in ones in those days) in a forum like this resulted in a barrage of responses talking about 'wastes of money', 'snake oil' and suchlike - but some of those who used to make such comments are today advocating (or stronger) the use of SPDs in CUs !

My personal view is that the benefits are theoretical, and I'm far from convinced that SPDs (of any type) really offer any significant benefit. For what it's worth, for many years I have lived with what is almost certainly an 'above-average' amount of theoretically 'susceptible' electronic equipment (probably much of which has been more 'susceptible' than modern stuff) and have experienced extremely few (if any incidents of 'premature failures' which might possibly have been the consequence of 'mains surges'.

I'll be interested to hear what others have to say - and, as above, I suspect you'll get a whole spectrum of opinions!

Kind Regards, John

 

[jurassic sparkk]

As above, but if your really keen into getting 1 i suggest getting a risk assesment done.

 

[ericmark]

I have to agree with @JohnW2 my thoughts were and surge protection required should be built into the equipment requiring it.

However most the old filters in some way connected to earth, and going back pre-2008 it was a problem running 20 PC's in a room as the earth leakage combined together could cause the RCD to trip. So the filters fitted today may be as not as good as they use to be. But only guessing.

But expensive equipment still seems well protected, the items at risk are more likely to be cheap items, so the question is did they fail due to spikes, or poor manufacture?

I have 2 x SPD's fitted, in the last 4 years I have replaced around 6 LED lamps, my son has no SPD's and has lost around 20 LED lamps, most GU10, and he claims using cheap bulbs, but I also use cheap bulbs.

However I never fitted SPD's to save equipment, they came with the consumer units, and I left them in. Other than LED bulbs, only items lost have been VCR's which were likely due to atmospheric storms and surges down the aerial lead, and a SPD in the supply would not have helped.

 

[JohnW2]

But expensive equipment still seems well protected, the items at risk are more likely to be cheap items, so the question is did they fail due to spikes, or poor manufacture?

... or even just because 'things sometimes fail', even if well manufactured.

Kind Regards, John

 

[flameport]

, but are they reliable

Designed to last for many years in a typical installation.
They could fail after some massive transient event, but that's the whole point - they fail, other things do not.

do they offer the same level of protection as one of those plug in ones?

No.
Those intended for consumer units (T2) deal with much higher energy levels than the plug in / extension lead variety. However by doing that, they can't deal with all of the energy, and some will get through.
The extension lead / plug in devices (T3) deal with most of what's left after the T2.

If you use T3 devices on their own, there is a very high possibility of them not removing all of a transient or being destroyed in the process.

If you have T2 on it's own, then most devices probably won't be damaged, particularly if they have their own T3 or equivalent internally. However it may be desirable to still have T3 for certain pieces of equipment.

 

[flameport]

I assume this would be the correct part for my CU?

That is the correct part, but installation involves moving the whole internal assembly to the left by 2 modules, which also involves moving the incoming tails and main switch.
Unless there is an external isolator, this is NOT something that should be attempted by DIY.

Even with an external isolator, all of the connections inside the consumer unit will need to be checked afterwards, as moving things will inevitably result in loose connections.

 

[ebee]

I look at it this way.
Historically, in most areas, this has not been a big problem
Telephone lines have, for a long time now, had surge arrestors in them.
More relatively recently, people tend to use extension leads etc with surge arrestors built in.
Relatively, even more recently, people are getting more and more expensive hi tech stuff in their homes so having an SPD might give you an extra chance of saving from destruction some expensive equipment.
I would say the cost benefit of having them is probably worthwhile.
They will not save equipment from every possible event and not from lightning (much) getting into the mains supply or telephone lines.
However I would tend to recommend having them.
Yesteryears equipment and appliances did not care as much about nasty spikes and we did not have anywhere near as much of it in our homes.
Today is different. At worst, it might be a small amount of money that you did not really need to spend.

 

[SUNRAY]

In my opinion the way we wire them into the system they are unlikely to have much effect, chances are the MCB would trip if it did do anything and then be unprotected...
Absolutely appalling method of installing a dubious device. But an excellent way of getting people to spend money.

 

[JohnW2]

..... Relatively, even more recently, people are getting more and more expensive hi tech stuff in their homes so having an SPD might give you an extra chance of saving from destruction some expensive equipment.
I would say the cost benefit of having them is probably worthwhile.
Today is different. At worst, it might be a small amount of money that you did not really need to spend.

Experiences will obviously vary and, as with any sort of 'insurance', it is all inevitably probabilistic (i.e. a gamble').

I can speak only of my personal experiences, and the experiences of those close to me but, as I've said, despite having lived with a large amount of electronic equipment (probably more than most) I would probably struggle to think of any 'losses of equipment'; in the past 50+ years that I might reasonably suspect might have been caused by mains spikes/surges/whatever.

So, if it had been possible for me to have SPDs in every new CU I've had installed during those 50+ years, I strongly suspect that, personally, I would probably be ('overall') 'out of pocket' as a result.

One of the difficulties is that it is (for fairly obvious reasons) almost (or completely!) impossible to get any data ('chapter and verse') about how many items of equipment really are damaged or destroyed by supply voltage issues - which means that the arguments (and decisions) are necessarily primarily 'theoretical'.

Kind Regards, John

 

[ΩΩΩ]

Surge is pretty much a requirement on all new installs.
The company Surge devices have some good content and advice, which may help in you decision, and they are very helpful.
You have the space in the board. The actual surge kit would be about £60, with Labour £200 would be a ball park amount.
Peace of mind, possibly.

 

[JohnW2]

Surge is pretty much a requirement on all new installs.

Although we are moving in that direction, regulatory-wise, that certainly doesn't mean that SPDs are wanted,or regarded as 'cost-effective', bu everyone

Peace of mind, possibly.

That's what insurance salesmen always say.

I find this development in BS7671 to be rather worrying. Hitherto (as with the Wiring Regs before it), it has always been essentially, directly or indirectly, about ('personal') safety. We are now seeing it starting to move in a different direction, which seems to be at risk of representing an unwelcome intrusion on 'freedom of personal choice'.

If that's the direction in which we are moving, what will be next, I wonder? Will we perhaps see 'compulsory' insurance of (buying ';extended warranties' for) almost everything we buy (washing machines, boilers, cars ..... etc. etc.) - again, no doubt sold as "for peace of mind"?

Kind Regards, John

 

[FrodoOne]

Hi all,

I have quite a bit of electrical kit at home that I would be gutted to lose in the event of a mains surge - a high end gaming PC, a server and some old games consoles from my childhood that I would be devastated to lose.

I have a couple of plug in surge protectors like this but I have been wondering lately if an SPD in the consumer unit would be a valuable addition to our installation.
Wouldn't have to panic then when I forget to use the plug in surge suppressors.

Seems like a good idea, but are they reliable and do they offer the same level of protection as one of those plug in ones?

Finally, is the installation of these devices appropriate to be undertaken by a competent DIYer or should I get an electrician out?

For reference, here is the Hager branded CU from 2016 when the house was built:
View attachment 322854View attachment 322853

I assume this would be the correct part for my CU?

Thank you all in advance for the advice. Also keen to hear the opinions of those on here who are sparks by trade.

Your CU seems to have a SPD similar to one of the two installed in this Australian "Switchboard".

If you live in a "Built-up" area of a UK city, you may not need one.
However, if you live in an open area (such as is normal in Australia or North America) (or in the UK "Countryside"), such SPCs would be a good investment.

The SPCs shown were installed after a "Nearby" Lightning Strike caused certain Garden Lighting devices to become "inoperative".

 

[ebee]

Although we are moving in that direction, regulatory-wise, that certainly doesn't mean that SPDs are wanted,or regarded as 'cost-effective', bu everyone

That's what insurance salesmen always say.

I find this development in BS7671 to be rather worrying. Hitherto (as with the Wiring Regs before it), it has always been essentially, directly or indirectly, about ('personal') safety. We are now seeing it starting to move in a different direction, which seems to be at risk of representing an unwelcome intrusion on 'freedom of personal choice'.

If that's the direction in which we are moving, what will be next, I wonder? Will we perhaps see 'compulsory' insurance of (buying ';extended warranties' for) almost everything we buy (washing machines, boilers, cars ..... etc. etc.) - again, no doubt sold as "for peace of mind"?

Kind Regards, John

My thoughts exactly, I could not have put it better myself.
People (Cusutomers and Traders alike) believe that the life of something is legally limited by the length of the manufacturers/sellers gurantee.
It is not - as I`ve mentioned in the past, some years ago, I advised a potential customer to seek help from trading standards following their cooker failing after 18 months (12 months guarantee, extended warranty declined) result rapid success after TSO telephone call.
Similarly, which magazine a legal services customer, took on a huge national chain, which intervened in letter to the firm, no result , digging in.
The firm was trying to take a similar stance to the previous example. Which advised the customer to take it to court, the judge confirmed that white goods have automatic 6 years guarantee without extended warranty or manufacturers warranty etc .
Since that time it bacame a bit more clarified in law that other items had legal life expentances way beyond these puny guarantees and warranties. A TV, for example, might well have a 3 year or 5 year effective guarantee for instance, irresepective of any guarantee thrown in at the time of the sale and any offer of buying an extended warranty.

That`s why I baulk at a trade orginisation stating "Our tradesmen are so good that they give a full 12 months guarantee" or some such wording in the advert .
I read it as "Our tradesmen are so crap that it will be expected that they will attempt to limit some liabillity so you might need to take them to court in order to enforce your rights as a consumer". Most people do accept the sellers/manufacturers/installers false statements and just roll over but some of us do not.

 

[JohnW2]

My thoughts exactly, I could not have put it better myself.

'Like minds', again!

I agree with everything you say, with one caveat (in relation to SPDs) ... the protection provided by law ('fitness for purpose for a reasonable period of time) presumably does not relate (in terms of manufacturers'/retailers' responsibilities) to failures of products due to factors beyond the control of the manufacturer/retailer.

Hence, if the proponents of SPDs manage to convince people (including Courts) that SPDs are an important factor in preventing premature failure of products, then the Courts might at least take the absence of such protection in mitigation when assessing the degree of a manufacturer's responsibilities (as they presumably would in any case in which it seemed that the buyer has not 'taken reasonable steps' to ensure the product didn't come to harm') - or, at worst, dismiss the claim completely for that reason?

Kind Regards, John
Edit: confused wording rectified!