UK Is an SPD required for a loft conversion?

[nicebutdim]

Out of interest, has anyone ever had to replaced an spd because of a surge or seen one that’s done its job?

I've seen one with red flags on 2 of 3 phases. Who knows how long it had been like that? Mad that I've also seen them in new industrial installations with no link to BMS.

 

[mainline]

Out of interest, has anyone ever had to replaced an spd because of a surge or seen one that’s done its job?

Seen one that seems to have done its job on a housing estate that had a mains surge.
Quite a few houses were fitted with the same make combi boilers.
All failed except the one that had an spd board recently fitted.

 

[mainline]

No regulatory body is going to force an Electrician to not fit surge protection.

It’s more to do with trying to force the electrician to sign off his work.
The installer has no right for not doing so.

 

[oscar21]

You're surely not expecting the SPD manufacturer to replace your TV whenever it goes faulty? Am I missing something?

I'm playing devils advocate, what I was trying to say is, if you don't have a surge protector then your TV will break, possibly because of a surge (unlikely but possible) but probably because its made of crap. If you do have an SPD fitted your TV will still break because its made of crap, no surge protector will stop that, but you are down £250.

Surely the most sensible thing to do with £250 is buy some sort of insurance policy that protects electronic stuff against damage.

And how come this wasn't a problem a few years ago, metal oxide varistors have been around since adam was a lad, there was never any need to fit them 10 years ago to anything. Are TV sales going to fall off a cliff now we are getting surge protectors, if that was true the tory mates that own big electronic business would never allow them.

 

[DPG]

I'm playing devils advocate, what I was trying to say is, if you don't have a surge protector then your TV will break, possibly because of a surge (unlikely but possible) but probably because its made of crap. If you do have an SPD fitted your TV will still break because its made of crap, no surge protector will stop that, but you are down £250.

Surely the most sensible thing to do with £250 is buy some sort of insurance policy that protects electronic stuff against damage.

And how come this wasn't a problem a few years ago, metal oxide varistors have been around since adam was a lad, there was never any need to fit them 10 years ago to anything. Are TV sales going to fall off a cliff now we are getting surge protectors, if that was true the tory mates that own big electronic business would never allow them.

Too many conspiracy theories in that for me.

You could say the same thing about many things. As an example, RCDs were around for years before they were enforced in the regs.

I'm from an electronics background, and I think I might have mentioned before a story about a company that tried to cut costs by removing surge protection components from a product. Guess what happened - product return rates went up, especially in regions more prone to storms. Nothing to do with some imagined 'built in expiry time' by the manufacturer.

It's not that there was 'never a need to fit them'. And it's nothing to do with the Tories!

 

[oscar21]

Too many conspiracy theories in that for me.

You could say the same thing about many things. As an example, RCDs were around for years before they were enforced in the regs.

I'm from an electronics background, and I think I might have mentioned before a story about a company that tried to cut costs by removing surge protection components from a product. Guess what happened - product return rates went up, especially in regions more prone to storms. Nothing to do with some imagined 'built in expiry time' by the manufacturer.

It's not that there was 'never a need to fit them'. And it's nothing to do with the Tories!

Doesn't most of the electronic stuff have surge protection built in anyway, a lot of the stuff Big Clive takes to bits has those blue MOV inside already. and of course stuff has a built in expiry time, even the original humble light bulb

 

[DPG]

Doesn't most of the electronic stuff have surge protection built in anyway, a lot of the stuff Big Clive takes to bits has those blue MOV inside already. and of course stuff has a built in expiry time, even the original humble light bulb

Some stuff does, some stuff doesn't. Some decent quality items usually have good surge protection, but a lot of things have the bare minimum to keep costs down. But I would always recommend a decent SPD be fitted at the consumer unit to be on the safe side. Especially with the amount of electronic equipment people have these days.

 

[nicebutdim]

I'm playing devils advocate, what I was trying to say is, if you don't have a surge protector then your TV will break, possibly because of a surge (unlikely but possible) but probably because its made of crap. If you do have an SPD fitted your TV will still break because its made of crap, no surge protector will stop that, but you are down £250.

Surely the most sensible thing to do with £250 is buy some sort of insurance policy that protects electronic stuff against damage.

And how come this wasn't a problem a few years ago, metal oxide varistors have been around since adam was a lad, there was never any need to fit them 10 years ago to anything. Are TV sales going to fall off a cliff now we are getting surge protectors, if that was true the tory mates that own big electronic business would never allow them.

Better playing devil's advocate in a letter to the IET as it is they who write the regulations you're generally obliged to work to.

I see the point you're making and understand it, but you lost me with the pointless politicisation of your argument. Unless you know how the people responsible for writing BS7671 vote, then this seems like agitation for agitation's sake and would be better left at the door.

 

[pc1966]

Doesn't most of the electronic stuff have surge protection built in anyway, a lot of the stuff Big Clive takes to bits has those blue MOV inside already. and of course stuff has a built in expiry time, even the original humble light bulb

All reputable electronics will meet the relevant EU (now UK) standard for conducted immunity which includes such mains borne surges. All of that came in around 1996 with the EMC directive as before that time it was down the the manufacturer's ethics if they would meet any given immunity requirement or not (emissions were regulated way back due to impact on radio/TV).

Not that the EMC directive seems to matter much as it is largely self-policed so you can see where that is going...

But...the levels involved to meet that are quite low, off hand I don't know what is current but it used to be in the 1-2kV sort of region. How you achieve it is not specified, it might be MOV added to dissipate/clamp the surge, over-rated parts to survive it, or LC filters to reflect the high frequency part, etc, etc.

The purpose of the mains incoming SPD is to deal with the "big stuff" where you get tens of kA peak and energies of dozens of Joules, those would fry the protection built in to most end-use products. Hence the Type 1/2 at the CU (depending if direct/induced lightning rating) and Type 3 at the product (if needed).

Having SPD fitted does not guarantee that stuff will survive, nor does it deal with crap eBay-level imports, but it improves your chances!

 

[nicebutdim]

Ought to be a disclaimer posted for any newish member posting a thread, to warn them of the likely outcome of their actions

 

[pc1966]

I've seen one with red flags on 2 of 3 phases. Who knows how long it had been like that? Mad that I've also seen them in new industrial installations with no link to BMS.

Indeed, most of the better quality SPD have the switch for an indicator but rarely used. We did, using the wonders of diodes and the diode-action of the LED indicators, to have 3 'fail' lights and one 'good' light that was logical AND of the status:

The SPD on the left is the 'DB' one, there are others at the incoming points for mains and for backup generator.

 

[Mike Johnson]

The three phase surge protector I had on my board in France had separate plug in modules for each phase after replacing them for I think the third time at a not inconsiderable cost, I removed them and just remembered to switch everything off when a storm approached, once had the living room lit up by a lightning ball travelling through the house most interesting.

 

[pc1966]

The three phase surge protector I had on my board in France had separate plug in modules for each phase after replacing them for I think the third time at a not inconsiderable cost, I removed them and just remembered to switch everything off when a storm approached, once had the living room lit up by a lightning ball travelling through the house most interesting.

Clearly not rated for the job!

Fit Type 1 SPD if you have a rural site / overhead line / high lightning incidence situation.

 

[Mike Johnson]

Probably right, when I installed the SPD about ten years ago, I knew nothing about them, not much has changed since then.

 

[nicebutdim]

Indeed, most of the better quality SPD have the switch for an indicator but rarely used. We did, using the wonders of diodes and the diode-action of the LED indicators, to have 3 'fail' lights and one 'good' light that was logical AND of the status:
View attachment 109777

The SPD on the left is the 'DB' one, there are others at the incoming points for mains and for backup generator.

I'm guessing someone pokes their head in that room on a regular basis. Imagine high value processes being protected by an SPD which remains locked away in a switch room where no one might check its status for weeks on end. Power won't ever be interrupted, but SPD could be taken out today and equipment by a later surge and no one would understand what went wrong. Everything in buildings monitored to within an inch of its existence, yet this fairly critical piece of kit gets overlooked. The odds of two surges are probably remote, but linking surge protection back to BMS would be a relatively trivial cost.

 

[mainline]

Clearly not rated for the job!

Fit Type 1 SPD if you have a rural site / overhead line / high lightning incidence situation.

If you are in a rural environment it’s most likely to be TT earthing so more than likely neither would a type 1 spd.

 

[mainline]

I'm playing devils advocate, what I was trying to say is, if you don't have a surge protector then your TV will break, possibly because of a surge (unlikely but possible) but probably because its made of crap. If you do have an SPD fitted your TV will still break because its made of crap, no surge protector will stop that, but you are down £250.

Surely the most sensible thing to do with £250 is buy some sort of insurance policy that protects electronic stuff against damage.

And how come this wasn't a problem a few years ago, metal oxide varistors have been around since adam was a lad, there was never any need to fit them 10 years ago to anything. Are TV sales going to fall off a cliff now we are getting surge protectors, if that was true the tory mates that own big electronic business would never allow them.

A high percentage of fails in modern stuff is usually down to the use of smps power supplies.
A decent spd can only help to iron out the incoming supply and increase the chances of its survival.

 

[mainline]

Doesn't most of the electronic stuff have surge protection built in anyway, a lot of the stuff Big Clive takes to bits has those blue MOV inside already. and of course stuff has a built in expiry time, even the original humble light bulb

Bird rental video recorders had a time fuse in

If you don’t want to fit spd,s then don’t fit them.

 

[davesparks]

And how come this wasn't a problem a few years ago, metal oxide varistors have been around since adam was a lad, there was never any need to fit them 10 years ago to anything.

There was a real-world need for them 10 years ago, and even longer ago than that. The need for them has been increasing as the amount of sensitive electronics in the world increases.

 

[MJPD29]

I've seen one with red flags on 2 of 3 phases. Who knows how long it had been like that? Mad that I've also seen them in new industrial installations with no link to BMS.

I’ve never seen one activated. After some sites I’ve seen recently that have suffered from lighting strikes I’m starting to wonder how useful some of them are.