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It’s applicable to all installs no matter whether in a commercial or domestic setting.

I think it’s a very brave move to not install SPD’s as standard

With AFDD’s you can make a case in some circumstances to leave them out but given the detail for SPD’s in regs I simply can’t see anyone has the same ability not to install them given the detail required to assess the need
 
The Hager 18th seminar chap basically said when it comes to single dwellings then if it’s TT/overhead or has PV install a SPD.....If it doesn’t then you don’t really have to worry about it.
 
I fitted an spd in the CU in my flat when i changed it over to all rcbo's Hager SPD's not that big compared to some. has a type c 125A MCB then SPD modules the size of standard mcb, its a sort of carrier where the spd part can be popped out and replaced if required.
Back when I fitted it, it came to £68.
the mcb links to spd via a piece of 6mm brown.
Fitted it as the people who wired my flat (new build) didnt fit one, the risk assessment said one was needed and coincidentally they came back to fit them in other flats after i raised it with freeholder!
 
Has anyone actually carried out the calculation assuming a few figures that you aren’t going to know like the length the supply cable to the DNO TX? Unless your bang on top of the TX I can’t see it ever being above 1000.

CRL = Fenv /(Lp x Ng)


Fenv is an environmental factor selected according to Table 443.1
Lp is the risk assessment length in kilometres, and
Ng is the lightning ground flash density measured in flashes per square kilometre per year relevant to the location of the power line and connected structure.

Unless you can get all the above info then your going to fitting them on commercial jobs..

For domestic a get-out-clause is given for ‘single-dwelling units’ where the ‘total value of the installation and equipment therein does not justify such protection”.


For someone with just a sky box and tv, doesn’t really justify such protection. For someone that has multimedia setups, intelegent lighting controls, smart heating controls and so on it probably does justify having one fitted.

For the cost of them which aren’t massively expensive then it would be worth having a chat with the customer about having one fitted. Last house I done spent 7K on a HDMI matrix so I don’t think he would be bothered about an extra 60 quid for a SPD.
 
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I don't have a position on the changed requirements for spd as yet. But what I do know is I've not seen one in a single dwelling and I'm not had any complaints from my little band of Customers that any equipment has ever suffered. Hmmm
 
Hey guys
This is Napits take regarding SPD’s in domestic single dwellings
I’m going to an niceic tech talk the 6th December and will report back what their guidance/ stance is regarding the matter
Note that the lack of need of the CRL is not required for domestic dwellings or necessarily the need of SPD’s according to their advice Spd & 18th..............,,,,,, E102E8AB-D7F4-407E-8125-911B6D605906 - EletriciansForums.net Spd & 18th..............,,,,,, 3BB0DC3D-9DA4-4D9B-92E5-C9EF9FE5F615 - EletriciansForums.net
 
Has anyone actually carried out the calculation assuming a few figures that you aren’t going to know like the length the supply cable to the DNO TX? Unless your bang on top of the TX I can’t see it ever being above 1000.

CRL = Fenv /(Lp x Ng)


Fenv is an environmental factor selected according to Table 443.1
Lp is the risk assessment length in kilometres, and
Ng is the lightning ground flash density measured in flashes per square kilometre per year relevant to the location of the power line and connected structure.

Unless you can get all the above info then your going to fitting them on commercial jobs..

For domestic a get-out-clause is given for ‘single-dwelling units’ where the ‘total value of the installation and equipment therein does not justify such protection”.


For someone with just a sky box and tv, doesn’t really justify such protection. For someone that has multimedia setups, intelegent lighting controls, smart heating controls and so on it probably does justify having one fitted.

For the cost of them which aren’t massively expensive then it would be worth having a chat with the customer about having one fitted. Last house I done spent 7K on a HDMI matrix so I don’t think he would be bothered about an extra 60 quid for a SPD.
So you think we can only realistically install type 2 and type 3 in non domestic installations as with a type 1 you would require an LPZ in place which I understand would require a risk assessment done for lighting strikes on the building, something that I couldn’t advise on and would struggle to put across to a client to justify needing one.
Normally larger new build commercial jobs where the design aspect is out of the installers duties as when done by a consultant it would be specifie (lighting protection)
 
So you think we can only realistically install type 2 and type 3 in non domestic installations as with a type 1 you would require an LPZ in place which I understand would require a risk assessment done for lighting strikes on the building, something that I couldn’t advise on and would struggle to put across to a client to justify needing one.
Normally larger new build commercial jobs where the design aspect is out of the installers duties as when done by a consultant it would be specifie (lighting protection)

From what I’ve read a type 2+1 SPD for TT overhead.

Type 2 if underground

type 1 or type 2+1 if lightning protection in place

https://www.hager.co.uk/files/download/0/4540_1/0/Surge_Protection_Guide.pdf

Page 17 quick selection guide of SPD’s
 
if only applies to commercial only .
wait until the Chinese get their act together the price will drop.

That is not correct. In single dwellings then if the value of equipment protected is less than the cost to install an SPD then no SPD required. However; if the dwelling had medical electrical equipment in then it would require SPD protection.
 
So am i correct than reg 443.4 means unless we provide a risk assesment that states why we are not using a spd in consumer unit changes then we must fit one??

The reg does not say you need to provide one. Just that one needs to be carried out.
 
That’s how I interpret it.

Not sure how you can carry out a risk assessment however because it states that you have to do a calculation with the different lengths of each element of the distributions various cable lengths.

Lpal, Lpcl, Lpah & Lpch

Other than asking the DNO not sure how these can be determined.

So I guess the only real way is to add type 2 devices to each CU adding £200+ to each job?

Table 443.1 tells you what to do when the distance of the network cable is unknown.
 
The Hager 18th seminar chap basically said when it comes to single dwellings then if it’s TT/overhead or has PV install a SPD.....If it doesn’t then you don’t really have to worry about it.

Sounds like they are talking crap. No mention whatsoever of supply arrangements in the regs.
 
Has anyone actually carried out the calculation assuming a few figures that you aren’t going to know like the length the supply cable to the DNO TX? Unless your bang on top of the TX I can’t see it ever being above 1000.

CRL = Fenv /(Lp x Ng)


Fenv is an environmental factor selected according to Table 443.1
Lp is the risk assessment length in kilometres, and
Ng is the lightning ground flash density measured in flashes per square kilometre per year relevant to the location of the power line and connected structure.

Unless you can get all the above info then your going to fitting them on commercial jobs..

For domestic a get-out-clause is given for ‘single-dwelling units’ where the ‘total value of the installation and equipment therein does not justify such protection”.


For someone with just a sky box and tv, doesn’t really justify such protection. For someone that has multimedia setups, intelegent lighting controls, smart heating controls and so on it probably does justify having one fitted.

For the cost of them which aren’t massively expensive then it would be worth having a chat with the customer about having one fitted. Last house I done spent 7K on a HDMI matrix so I don’t think he would be bothered about an extra 60 quid for a SPD.

I think not to install them would be a non-conformance. Personally I won’t be giving an option. If they need them then my quote will have them in or I won’t be doing the works.
 
all I know that is you have a LPZ then a type 1 is required at the origin to protect against lightning strikes.
As regulation 543.4.1.1 refers an spd installed at the origin shall be a type 1 or 2.
Regulation 534.4.1.4 says that where the structure is not equipped with an external lightning system or doesn’t require protection against lightning strikes,type 2 SPD’s shall be installed as close as possible to the origin.

So by that I conclude that SPD’s of a type 1 nature are not required if you have no LPZ
 

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