Was talking to my cousin on the w/e.

He used to be a BT engineer (GPO trained), took the
Voluntary redundancy package in 2000 and got a job at
local college setting and testing the gear used on the
electricians courses, so is effectively Part 17 in
all but piece of paper.

He says part 18 will require all properties that are
within 1 Km of a church or tower block with lightning
rods, will need to be fitted with surge protection devices.

Seems a bit extreme.

Who is going to measure that 1Km ?.

Also problems for people with electric cars parked
on the drive of the premises. These will (he thinks)
need more earth rods than will be practical to fulfil
some other new requirement.

Andrew wrote:

He says part 18

IET 18th edition?

will require all properties that are within 1 Km of a church or tower
block with lightning rods,

Not heard the "within 1km of a church" wording anywhere else, sounds
like bollox

will need to be fitted with surge protection devices.

In any case, SPDs don't apply to single dwellings

https://the-regs.co.uk/blog/?p=492

On Mon, 21 Jan 2019 20:26:57 +0000, Andrew wrote:

He says part 18 will require all properties that are within 1 Km of a
church or tower block with lightning rods, will need to be fitted with
surge protection devices.

No,he is reading it wrongly. There is a risk assessment that needs to be
satisfied. TBH, not much has changed, but the IET are making people aware
of the changes to the Regs, and increased the scope of the chapter on
lightning etc.
The local Church tower is not relevant, it states : 'this section deals
with direct strikes to the supply systems .... it does not specify
protection against...direct or nearby strikes on the structure'.


Who is going to measure that 1Km ?.

The RA goes into some detail, and gives a map of strikes per year per
km/2., the figure for which is used in the calculation.
Overhead supplies are more at risk than underground. It also has 4
examples that should be protected, all of which make sense -
'protection.. shall be provided where the consequence .. could be..1,
injury or loss of life.2, interruption of public services or damage to
cultural heritage, 3, interruption of commercial activity, 4, affect a
large number of colocated individuals.

The course I went on went into some detail about this. 1 is self
explanatory,but it is hard to see how to mitigate it, unless you do the
RA. 2, government/council buildings/museums that could have their electic
systems damaged by a lightning strike in the area, 3, self explanatory, 4
blocks of flats. But what is a large number - 10? 100?
Typically, the above should all be designed to make sure the people are
safe, and little damage will occur if there is a strike on the feed
cables.

It then says 'protection shall be provided.. except for single dwelling
units where the value of equipment does not justify such protection'.

OK, this came up on the IET forum, with a solid argument that the
majority of houses will not need it. There is a one in a 50,000 chance of
a strike in your area (just an example). 50000 houses at £100+ each to
fit an adequate SPD will be £5million. Then what is the cost of a few
electical appliances being burnt out by a strike? Far less overall than
the total cost of fitting the devices. So, on a purely risk based
assessment, you would not fit one in a typical house.

Also problems for people with electric cars parked on the drive of the
premises. These will (he thinks)
need more earth rods than will be practical to fulfil some other new
requirement.

That is still being debated. Many say they should be TT, others says you
then have earth gradients to the house TN system. Say you are using a
hoover plugged into the house to clean the car while it is plugged into
the charger.Different earth voltages, and the risk of a shock when
touching metalwork between the 2 devices. No easy solution, but, the
present situation of a mixture of earthing hasnt led to multiple deaths
yet.

No, it will not be done. Its another one of those pie in the sky things that
are impractical to achieve and in any case, I have yet to see proof that
any kind of surge protection is going to stop problems from lightening.
Remember I was almost struck by it twice, but the buildings nearby were
trashed from all wiring and electronics points of view, however many others
nearby were not affected, so its a variable feast indeed and trying to
achieve some utopia here is crap.
Brian

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"Andrew" wrote in message
...
Was talking to my cousin on the w/e.

He used to be a BT engineer (GPO trained), took the
Voluntary redundancy package in 2000 and got a job at
local college setting and testing the gear used on the
electricians courses, so is effectively Part 17 in
all but piece of paper.

He says part 18 will require all properties that are
within 1 Km of a church or tower block with lightning
rods, will need to be fitted with surge protection devices.

Seems a bit extreme.

Who is going to measure that 1Km ?.

Also problems for people with electric cars parked
on the drive of the premises. These will (he thinks)
need more earth rods than will be practical to fulfil
some other new requirement.

Brian Gaff wrote:

Its another one of those pie in the sky things that
are impractical to achieve

The equipment manufacturers seem to have realised that leaning on the
IET to force adoption of arc fault and surge protection products is more
fruitful than trying to convince people to buy them.

taking their lead from the "eco" central heating pump manufacturers.

In article ,
Andy Burns writes:
Brian Gaff wrote:

Its another one of those pie in the sky things that
are impractical to achieve

The equipment manufacturers seem to have realised that leaning on the
IET to force adoption of arc fault and surge protection products is more
fruitful than trying to convince people to buy them.

taking their lead from the "eco" central heating pump manufacturers.

I've seen this more and more in the last few IET regs.
Used to regard them as a excellent document, but less so nowadays -
too much industry just trying to push their products into the regs.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

In article , Andy Burns
scribeth thus
Brian Gaff wrote:

Its another one of those pie in the sky things that
are impractical to achieve

The equipment manufacturers seem to have realised that leaning on the
IET to force adoption of arc fault and surge protection products is more
fruitful than trying to convince people to buy them.

taking their lead from the "eco" central heating pump manufacturers.

Looking after some radio and comms sites earthing and lightning
protection is more to do with 'eff off size earth conduction and shunts
rather than surge devices..

sounds like someone had nothing better to do that to spout some bollix
to sell more devices that are questionable in effect anyway..
--
Tony Sayer