On 17/03/2012 00:24, John Rumm wrote:

as an aside, I added some details to the end of the flex article the
other day for breaking down those harmonised codings:

http://wiki.diyfaq.org.uk/index.php?..._Cabl e_Codes

Ooh, that looks useful. Some quick suggestions:

- make "Understanding Harmonised Cable Codes" a separate article, (a)
shorter pages are better, (b) HAR codes also apply to non-flexible cables;

- it might not be immediately obvious that to describe the insulation
and sheath needs two codes from your table 2a, insul'n first, then sheath;

- I wonder if the big table is really necessary. Might it be simpler
just to quote a few examples. This would lend itself to also quoting
the British CMA code (6242Y, etc) to make a useful cross reference (i.e.
3 cols: har code, brit code, description - or similar)

--
Andy

On 17/03/2012 00:55, Andy Wade wrote:
On 17/03/2012 00:24, John Rumm wrote:

as an aside, I added some details to the end of the flex article the
other day for breaking down those harmonised codings:

http://wiki.diyfaq.org.uk/index.php?..._Cabl e_Codes


Ooh, that looks useful. Some quick suggestions:

- make "Understanding Harmonised Cable Codes" a separate article,

Yup...

(a)
shorter pages are better, (b) HAR codes also apply to non-flexible
cables;

Indeed - I worked that out as I was going through dodgy translations of
the spec... Having only seen them used on flex specs prior to that I had
assumed they only applied there - but since I had started, I though I
may as well finish!

- it might not be immediately obvious that to describe the insulation
and sheath needs two codes from your table 2a, insul'n first, then sheath;

Yes will add that... table 3 could also use some examples because
although that looks simple the real world uses seem to take multiple
trips through it to describe size of main conductors, then CPC etc where
they are different. There are some examples in the spec we can lift.

- I wonder if the big table is really necessary. Might it be simpler

So did I after fighting with the OCRed output of it to HTML and then
running it through a HTML to wiki code conversion!

just to quote a few examples. This would lend itself to also quoting the
British CMA code (6242Y, etc) to make a useful cross reference (i.e. 3
cols: har code, brit code, description - or similar)

Yup, like that idea... Might just stick that on as an extra quick lookup
table.

--
Cheers,

John.

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On 17/03/2012 03:02, John Rumm wrote:
On 17/03/2012 00:55, Andy Wade wrote:
On 17/03/2012 00:24, John Rumm wrote:


- make "Understanding Harmonised Cable Codes" a separate article,

Try this:

http://wiki.diyfaq.org.uk/index.php?..._cable_cod es

- it might not be immediately obvious that to describe the insulation
and sheath needs two codes from your table 2a, insul'n first, then
sheath;

See if the new note and example helps...

just to quote a few examples. This would lend itself to also quoting the
British CMA code (6242Y, etc) to make a useful cross reference (i.e. 3
cols: har code, brit code, description - or similar)

Yup, like that idea... Might just stick that on as an extra quick lookup
table.

Table started:

http://wiki.diyfaq.org.uk/index.php?...de_equivalents

Now what it needs is filling out (two of the codes I used there I
"created" from the descriptions in the BS - might want to check they
look plausible! The other I pinched from RS's description)



--
Cheers,

John.

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"Fred" wrote in message
...
Hi,

About ten years ago I bought an extension lead from Wickes. Not
knowing any better at the time, I bought a long one, thinking that a
long one could be used when long or short lengths were required,
whereas a short one could only be used for short lengths.

Then I came and read here and I learnt that long leads had
disadvantages. I can't remember now whether this was because of
voltage drop or fault currents, or may be both. Can someone remind me?

Anyway, some of my tools have started switching on and off
intermittently when plugged into the lead, and I can only assume that
over the years the contacts in the extension socket have been worn and
are not making a good connection to the plug.

So it is time to buy a new lead or leads. I seem to remember reading
that 1.5mm^2 cores could only be used safely up to 15m and 2.5mm^2
cores (in a caravan power lead) could be used up to 25m. Is there any
advantage to buying a short "caravan hook-up" cable to use for lengths
under 25m?

Otherwise I'm thinking I could use the cable from the Wickes lead, or
possibly use arctic flex as an improvement, to make some short leads.

TIA
Look inside the plug and socket for loose connections first.

Flexible cable after a while can get breaks inside the cable, They can be a
PITA to find but are usually near the ends.
Plug a light into the extention and work along it bending and flexing it.
You can usually determine where the break is. Cut the break off and
reconnect/replace the plug/socket.

On Mar 17, 12:27*am, Andy Wade wrote:
On 16/03/2012 18:43, RJS wrote:

[...]
"Arctic cable is only designed for outdoor use at 110v, we recommend
using HO7 RN-F rubber cable for temporary 230v outdoor use including
marquees."

Any thoughts?

It's correct. *You might like to read the two articles about this that
were published in the IET's /Wiring Matters/ fairly recently.

Firstly:http://electrical.theiet.org/wiring-...s.cfm?type=pdf

and the follow-up:http://electrical.theiet.org/wiring-...ables.cfm?type...

To summarise:

- 3183A 'arctic' cable made to BS 7919 Table 44 is suitable for handling
down to -25 deg. C, but is only intended for use on 110 V ('reduced low
voltage') systems. This cable type is explicitly described as not
suitable for outdoor use at "standard voltages" (meaning 230/400 V), nor
for use in industrial or agricultural buildings. [Ref. BS 7540-3 Guide
to use ...]

- The 'blue stuff' is not actually an arctic cable at all. It's an
ordinary duty cord to BS 6500, i.e. 3183Y or H05VV-F. It's fine for 230
V but shouldn't be handled at temperatures below +5 deg. C. It is not a
heavy duty cable.

- For heavy duty, use H07RN-F, as already mentioned.

--
Andy

Hi Andy

It's interesting to note that you and js-b1 disagree entirely about
the Arctic cable.

At the moment the cable to my arc welder is extended with ordinary
(white) flex - bought in order to get a job done in a hurry - which is
far from flexible in cold weather and, while attached to the welder, a
bugger to coil up for easy storage . I was weighing up the costs of
replacing it with H07 and a Commando plug/connector at the welder end
to make the whole lot easier to transport. However, 15m of 4.0mm H07
and a 32A Commando plug/connector pair costs more than I paid for the
welder!



I've found the BS refs for Arctic and H07:

THE USE OF 'ARCTIC' CABLE

It is common to see blue sheathed flexible cables, sometimes referred
to as 'arctic' cable used on temporary installations.

Manufactured to BS 7919 (not harmonized), this type of cable was
designed and is suitable for use on reduced low-voltage systems only,
e.g. construction site installations, e.g. 110 V centre tapped
transformers at 55 V - 0 - 55 V and often seen on temporary road works
traffic lights.


Cables for outdoor use should be rubber insulated and sheathed as
specified in BS 7919



Richard

On Mar 17, 10:30*am, RJS wrote:
It's interesting to note that you and js-b1 disagree entirely about
the Arctic cable.

Andy Wade is correct.

"Arctic" is a broad marketing designation.
The BS to which the cable is manufactured matters.

YELLOW Arctic to BS 7919 is 110V only.
- Only be used for 110V power tools and not 300/500V.

YELLOW Sold-As-Arctic can be to BS 6500 and is 300/500V.
- Standard on extension reels from JCB, 1.25mm CSA, "Arctic" written
along its length, sold by Argos.

BLUE Sold-As-Arctic should be to BS 6500 and is 300/500V.
- Some extension reel makers do actually use it, commonly used for
caravan hookups. They would be better off using H07RNF re permanent
hookup in wet weather in conditions where cars, bikes etc trundle
about.

Not sure if anything in BS 6500 prevents a super-flexible sheath /
same material as BS 7919. It comes down to whether BS 6500 standard
actually specifies the sheath composition (GP4 GP8 etc). I have seen
reels of yellow sold-as-Arctic to BS 6500 on Ebay, because I returned
some in 2010 (in two places the insulated cores bulged out through the
sheath).

Doing a quick scan of Farnell and five electrical wholesalers. A
common theme is the wording "Arctic Grade". Anyone actually
trademarked "Arctic"?

"Yellow Arctic"
"300/500V"
"-20oC to +70oC operating"
"-40oC cold bend test temperature"
"3183Y"
"Sheath - Type 8 Arctic Grade PVC"

Interesting engineering specs say "-20oC operating", whilst marketing
not one to be left out say "-40oC cold bend test temperature".

I have seen caravan flex using straight labelled BS 6500 both in
orange & blue, because I bought some for the cable as cheap and local.
For a caravan a +5oC rating is useless - H05VV-F is the flex supplying
your PC.

Interesting green cable labelled "Arctic" to H03VV-F, 300/300V. Last
time I saw green H03VV-F 3G0.75 was on a kettle.

Finding a UK manufacturer AEI cables, most online Arctic are turkey/
asia/china...


http://www.aeicables.co.uk/products/...sp?code=CONS13

3183Y AG (Arctic Grade)

Voltage Rating
300/500 volts

Description
PVC Ordinary Duty Flexible Cords (Arctic Grade). These cords retain
their flexibility at low temperatures, to -25C, and are therefore
suitable for indoor and outdoor use to feed equipment such as
temporary traffic lights and portable tools.

Construction
Flexible plain copper conductors, low temperature PVC insulation,
cores laid up, low temperature PVC sheath.

Operating Temperature
-25degC to +70degC

Sheath Colour
Blue or Yellow

Manufacturing Standard
BS7919 Table 44

Datasheet confirms voltage rating 0.3kV/0.5kV


Arctic cable from AEI is to BS7919 Table 44 and available in Blue
which is the colour coding for 230V, and has a voltage rating of 0.3kV/
0.5kV for Yellow. I can understand JCB using yellow for their 230V
extension leads re colour symbolism, but why not do orange flex with
yellow JCB logo or luxo-model with H07RNF and yellow JCB logo on a
bright yellow reel?

On 17/03/2012 00:06, Lobster wrote:
On 15/03/2012 15:36, Martin Brown wrote:
On 15/03/2012 15:27, Hugh - Was Invisible wrote:
On Thu, 15 Mar 2012 13:42:47 -0000, Fred
wrote:

About ten years ago I bought an extension lead from Wickes. Not
knowing any better at the time, I bought a long one, thinking that a
long one could be used when long or short lengths were required,
whereas a short one could only be used for short lengths.

Biggest problem with modern long leads is that if you use much power you
have to unwind the whole lot to prevent overheating. If you use thicker
cable you add to the size and weight. Intermittently used power tools
are probably not a problem but our wallpaper steamer is.

Or in the case of our local church fete a pair of 3kW kettles on a
mostly rolled up mad hot extension lead plugged into the wall. They did
it last year as well completely melting the inside of the reel. *SCARY*

Unfortunately your average lay person has no clue about the different
current consumptions of different appliances, and the significance thereof.

Even if they (often only vaguely) understand that a 3-bar electric fire
is more expensive to run than a 100mA phone charger, they have no
concept of what the different currents involved actually mean, and what
the safety implications are.

Which when you think about it is actually a good testimony of the
quality of engineering that went into designing our electrical systems
and wiring accessories. In spite of a largely clueless user base, the
numbers removed from the gene pool Darwin style, are vanishingly small! ;-)


--
Cheers,

John.

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On Mar 17, 1:12*pm, "js.b1" wrote:
Interesting engineering specs say "-20oC operating", whilst marketing
not one to be left out say "-40oC cold bend test temperature".

Nope, on this occasion -40oC is an important cold bend test
temperature.
- BASEC independently tested samples of selected ‘arctic grade’
cables.
- The sheathing and insulation of certain cables were found to
disintegrate when subjected to a cold bending test.
- This problem could result in a fire, short circuit or an electric
shock.

I do recall a pile of blue Arctic cable being seized at a warehouse,
but no reason given.

Wiring Matters article cites H07RNF, BS7671 says H05RNF is ok for
caravans:
- Reg 721.55.2.6
- The means of connection to the caravan pitch socket-outlet shall
comprise
- harmonized code designation H05RN-F (BS 7919) or equivalent

I do suspect H07RNF is likely to be a similar retail price or more
easily obtained.

Arctic is not used in the EU, hence there is no HAR coding.
Arctic is a deviation from a BS, some list it merely complying with
minimal BS related to copper stranding & cable insulation, right up to
BS7919 Table 44, BS6500 (quite a different standard) and designated
3183Y, 3183YAG.

AEI Arctic is 300/500V, PVC, BLUE, BS7919 Table 44.
For a permanent or winter caravan hookup I would be minded to use an
RN-F cable tho.

On Sat, 17 Mar 2012 08:18:18 -0700 (PDT), js.b1 wrote:

Wiring Matters article cites H07RNF, BS7671 says H05RNF is ok for
caravans:
- Reg 721.55.2.6
- The means of connection to the caravan pitch socket-outlet shall
comprise harmonized code designation H05RN-F (BS 7919) or equivalent

Facinating thread. The cable I use for my long heavy duty extensions
is sold as a "caravan hook up". The cable is
H05VV-F...

http://www.halfords.com/webapp/wcs/s...t_storeId_1000
1_catalogId_10151_productId_222607_langId_-1_categoryId_165745#tab4

http://tinyurl.com/6vzd7sb

VV isn't listed
in:

http://wiki.diyfaq.org.uk/index.php?...harmonised_cab
le_codes

B-)

--
Cheers
Dave.

On Fri, 16 Mar 2012 13:15:53 -0700 (PDT), js.b1 wrote:

I think I remember a 600W kettle once... it might be boiled by now,
must find it!

I've got a 100W kettle use it quite a bit, takes about 20 mins to
boil a large mug full of water. Runs off 12v mind and the lead does
get warm...

--
Cheers
Dave.

On Mar 18, 11:01*am, "Dave Liquorice"
wrote:
Facinating thread. The cable I use for my long heavy duty extensions
is sold as a "caravan hook up". The cable is H05VV-F...

H05VV-F is...
- H = Harmonised
- 05 = 300/500V
- V = PVC Insulation
- V = PVC Sheath
- F = Fine stranded (flex)

Might be a slight error in terminology, but what you have is standard
BS 6500 PVC flex.

Caravans & boating would be better served by H05RNF & H07RNF.
Any "heavy duty" merely refers to the current carrying capacity, the
cable construction is no different to PVC 3-core flex. It might have
ultra flexible insulation & ultra flexible sheath & pass the 40oC bend
test, but it is not a tough neoprene.

BS7671 says one thing.
Cable Makers produce something different. Arctic (Grade) flex from AEI
is to BS7919 Table 44 in Yellow & Blue to 300/500V rating.

There may be a perception rubber cables perish from the era of Tough
Rubber Sheathed mains cables. Ironically pond cables are RR, whose
sheath may still perish. Conversely RN cable, whose sheath is
neoprene, does not perish.

On 18/03/2012 11:01, Dave Liquorice wrote:

VV isn't listed

No but V is ;-)

in:

http://wiki.diyfaq.org.uk/index.php?...harmonised_cab
le_codes

Could I direct the learned gentleman to Andy W's comments above, and the
introduction for table 2 which was modified to include them:

"Table 2a gives you the insulating material and the designation of any
non metallic sheath. Hence you need *two sets of letters from this
table*, the first to describe the insulator used for the conductors
themselves, and the second to tell you about the material used for the
overall sheath. "

[my emphasis]

So in summary VV is PVC wire insulation, and PVC overall sheath.

--
Cheers,

John.

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On Thu, 15 Mar 2012 13:51:12 -0000, "Brian Gaff"
wrote:

Some of those older sockets were amenable to being taken apart and resprung
to make them work again. I found those four way ones tended to have a
problem where they connected to the bus bars. its all by pressure and over
the years things relax and get tarnished.

This is 2-way and I did wonder about giving the brass a little squeeze
with some pliers but I wasn't sure if I would be fighting a losing
battle.

On Fri, 16 Mar 2012 02:22:50 +1100, F Murtz
wrote:

Replace the sockets instead of buying new leads if they are structurally
sound.

This was a reel with integral sockets. I doubt I could buy replacement
sockets top fit in the reel, but yes, I had thought of using the cable
to attach to a new trailing socket. Thanks.

On Thu, 15 Mar 2012 15:36:30 +0000, Martin Brown
wrote:

I am inclined to the view now that they should include a thermal cutout!

I have seen some reels with a little switch on the front to press to
reset a thermal cutout. It sounds good in theory but I did wonder how
useful they were in practice and where the temperature was measured,
i.e. would it operate in time to be useful? E.g.

http://www.wickes.co.uk/13a-easi-ree...t/invt/156277/

On Fri, 16 Mar 2012 13:15:53 -0700 (PDT), "js.b1"
wrote:

For example of the four otherwise identical 700W heaters I have had,

Are these oil filled radiators by any chance? I was looking for
something to stop the garage freezing over winter and I saw some oil
filled rads that were rated 700W and I though t it was a strange
number. I thought the manufacturers would have aimed for 300W more to
make a kiloWatt. I thought 1000W sound better for marketing purposes!

On Thu, 15 Mar 2012 16:55:17 +0000 (GMT), "Dave Liquorice"
wrote:

If the cable is in otherwise good condition just replace the socket
and if the plug isn't an RCD one replace that as well. You may say
that all your 13A sockets are RCD protected but what if you use it
elsewhere?

I had thought of upgrading to 2.5mm^2 caravan cable but you are right,
it might be more than I really need.

The sockets in my house are RCD protected so I must confess I hadn't
really thought of adding an RCD to the extension lead but it is a good
point; I may take it to help someone somewhere else. The problem would
be that when you test the RCD at home, it would trip both the RCD on
the lead and the one in the consumer unit. Still, better safe than
sorry.

I can see the advantage of an RCD plug: it would protect the whole
lead in case it was cut by a lawn mower, hedge trimmer, circular saw,
etc. But is there a reason to have one at the socket end? I can't
remember whether there was an old post here suggesting tools be
plugged into an RCD at the end of very long extension leads because
they wouldn't trip RCDs a long way away. Is that right or have I got
that mixed up?

I ordered a cheap and cheerful rubber trailing socket from
Toolstation:
http://www.toolstation.com/shop/Elec.../sd2470/p36884

Has anyone used these before? My only hesitation is that there are two
slots in the back. I think they form part of the moulding for the
spring mechanism inside. My worry is that these would allow water in.
To be fair, the item does not claim to have an ip rating. I would not
be drilling outside or mowing the lawn when it is raining but what
about wallpaper steamers and pressure washers, where there could be
some water about? Should I return these for something more waterproof?

TIA

On Sat, 17 Mar 2012 00:27:18 +0000, Andy Wade
wrote:

http://electrical.theiet.org/wiring-...s.cfm?type=pdf

When I open this it warns me there is an error and it may not display
properly but it then appears to load perfectly. Does anyone else get
this message?

I am rather confused about the whole arctic cable thing. The article
says it cannot be used for 240V but does not say why. It does say that
arctic cable was only designed for 110V, so is it that using the cable
for 240V is not unsafe, just that it is outside the spec. because it
was spec'd for 110V on building sites?

I can't really see why a 1.5mm^2 arctic cable would not be suitable
for 240V when lots of other 1.5mm^2 CSA cables are. What am I missing?
Is there a reason the minimum temperature should be higher when used
with 240V? I can't see I would need a cable in -25C, though the other
winter perhaps some people would have.

Is it just about different definitions of "arctic cable"? For example
"BS7919 arctic cable" is only for 110V, whereas "arctic cable [no BS]"
is a cable for 240V down to -25C?

Otherwise why do Toolstation and others sell arctic cable for 240V
use?

http://www.toolstation.com/shop/Elec.../sd2730/p40121


A long time ago I bought some yellow arctic cable from Screwfix, in
the days before I realised that the blue and yellow had a
significance. I bought yellow so that I could have a highly visible
extension lead in my garden, so as not to lawn mow it. Was I wrong to
do this? Should yellow always be 110V only?

TIA

On Mar 29, 9:58*pm, Fred wrote:
On Thu, 15 Mar 2012 16:55:17 +0000 (GMT), "Dave Liquorice"

wrote:
If the cable is in otherwise good condition just replace the socket
and if the plug isn't an RCD one replace that as well. You may say
that all your 13A sockets are RCD protected but what if you use it
elsewhere?

I had thought of upgrading to 2.5mm^2 caravan cable but you are right,
it might be more than I really need.

On a 13A circuit it surely is. There's really no need or reason to
stick to regulation Vdrop limits unless you're runnning expensive-ish
refrigeration. Fault current times arent a significant issue on a 13A
fused RCDed supply.


The sockets in my house are RCD protected so I must confess I hadn't
really thought of adding an RCD to the extension lead but it is a good
point; I may take it to help someone somewhere else. The problem would
be that when you test the RCD at home, it would trip both the RCD on
the lead and the one in the consumer unit. Still, better safe than
sorry.

The problem is that RCD plugs are fragile. Get a rubber plug.


I can see the advantage of an RCD plug: it would protect the whole
lead in case it was cut by a lawn mower, hedge trimmer, circular saw,
etc. But is there a reason to have one at the socket end? I can't
remember whether there was an old post here suggesting tools be
plugged into an RCD at the end of very long extension leads because
they wouldn't trip RCDs a long way away. Is that right or have I got
that mixed up?

mixed up


I ordered a cheap and cheerful rubber trailing socket from
Toolstation:http://www.toolstation.com/shop/Elec...ads+RCDs/Rubbe...

Has anyone used these before? My only hesitation is that there are two
slots in the back. I think they form part of the moulding for the
spring mechanism inside. My worry is that these would allow water in.
To be fair, the item does not claim to have an ip rating. I would not
be drilling outside or mowing the lawn when it is raining but what
about wallpaper steamers and pressure washers, where there could be
some water about? Should I return these for something more waterproof?

TIA

You dont use 13A plugs & sockets anywhere they can get wet.


NT

On Thu, 29 Mar 2012 22:16:40 +0100, Fred wrote:

I can't really see why a 1.5mm^2 arctic cable would not be suitable
for 240V when lots of other 1.5mm^2 CSA cables are. What am I missing?

Probably the thickness/quality of the insulation.

I bought yellow so that I could have a highly visible extension lead in
my garden, so as not to lawn mow it. Was I wrong to do this? Should
yellow always be 110V only?

These days, ideally, yes. But for private use having something you
can see (provided it is suitably rated) has some advantages. 110v
won't be using 13A plugs and sockets but yellow ceeform that won't
mate with blue ceeform...

--
Cheers
Dave.

On Mar 29, 10:16*pm, Fred wrote:
On Sat, 17 Mar 2012 00:27:18 +0000, Andy Wade

wrote:
http://electrical.theiet.org/wiring-...ables.cfm?type...

When I open this it warns me there is an error and it may not display
properly but it then appears to load perfectly. Does anyone else get
this message?

I am rather confused about the whole arctic cable thing. The article
says it cannot be used for 240V but does not say why. It does say that
arctic cable was only designed for 110V, so is it that using the cable
for 240V is not unsafe, just that it is outside the spec. because it
was spec'd for 110V on building sites?

I can't really see why a 1.5mm^2 arctic cable would not be suitable
for 240V when lots of other 1.5mm^2 CSA cables are. What am I missing?

just intended for 110 use onsite. If you look at the cenelec code for
the cable you'll see what its V spec is - you need minimum 500v rating
for 240v ac use.

Is there a reason the minimum temperature should be higher when used
with 240V?

no

I can't see I would need a cable in -25C, though the other
winter perhaps some people would have.

Is it just about different definitions of "arctic cable"? For example
"BS7919 arctic cable" is only for 110V, whereas "arctic cable [no BS]"
is a cable for 240V down to -25C?

Otherwise why do Toolstation and others sell arctic cable for 240V
use?

for outdoor use in winter

http://www.toolstation.com/shop/Elec...%20PVC%20Cable...

A long time ago I bought some yellow arctic cable from Screwfix, in
the days before I realised that the blue and yellow had a
significance. I bought yellow so that I could have a highly visible
extension lead in my garden, so as not to lawn mow it. Was I wrong to
do this? Should yellow always be 110V only?

TIA

wrong if used on a building site. Elsewhere you can use any colour you
like. In some cases it'll confuse the people present, that's your
choice.


NT

On Mar 29, 9:36*pm, Fred wrote:
On Thu, 15 Mar 2012 13:51:12 -0000, "Brian Gaff"

wrote:
Some of those older sockets *were amenable to being taken apart and resprung
to make them work again. I found those four way ones tended to have a
problem where they connected to the bus bars. its all by pressure and over
the years things relax and get tarnished.

This is 2-way and I did wonder about giving the brass a little squeeze
with some pliers but I wasn't sure if I would be fighting a losing
battle.

It can be caused by muck and oxidation on the contacts, in which case
a touch with a ratstail file will fix it. It can also be caused by
excessive local heating, in which case the springiness will be gone.

NT