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

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.
Brian

--
Brian Gaff -
Note:- In order to reduce spam, any email without 'Brian Gaff'
in the display name may be lost.
Blind user, so no pictures please!
"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

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 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

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

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 13:42:47 -0000, Fred
wrote:

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

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.

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*

I am inclined to the view now that they should include a thermal cutout!
The clear warning on the reel has little or no effect on most folk

--
Regards,
Martin Brown

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*

I am inclined to the view now that they should include a thermal cutout!
The clear warning on the reel has little or no effect on most folk

The modern 50m JoJo ones do include the cutout these days... presumable
for this sort of reason.


--
Cheers,

John.

/================================================== ===============\
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|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

John Rumm 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* I am inclined to the view now that they should include a thermal
cutout! The clear warning on the reel has little or no effect on
most folk

The modern 50m JoJo ones do include the cutout these days...
presumable for this sort of reason.

The extension lead Geoff gave me has a thermal cut out and it has operated
twice.

Once when a pillock plugged in a 2kW heater without unwinding it (he was
told not to) and then again when another pillock decided to charge up two
cherry pickers without unwinding it (without asking to use it).

I was suprised at how long it took to reset the trip/cool down even after I
had unwound the lead.


--
Adam

On 15/03/2012 18:07, ARWadsworth wrote:
John Rumm 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:

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* I am inclined to the view now that they should include a thermal
cutout! The clear warning on the reel has little or no effect on
most folk

The modern 50m JoJo ones do include the cutout these days...
presumable for this sort of reason.

Had a look, but would want a 10m one or maybe 20m and they don't seem to
have thermal protect at least according to the summary at Farnell.

The extension lead Geoff gave me has a thermal cut out and it has operated
twice.

Once when a pillock plugged in a 2kW heater without unwinding it (he was
told not to) and then again when another pillock decided to charge up two
cherry pickers without unwinding it (without asking to use it).

I was suprised at how long it took to reset the trip/cool down even after I
had unwound the lead.

Still preferable to ending up with a molten mess of plastic and cable
all gummed up together. I was amazed the previous one didn't catch fire!

I also reckon they should be aggressively limited to no more than 20A
for 10s to avoid other obvious stupidity like 2 kettles which is an
overload condition on a 13A socket even with the cable unwound.

--
Regards,
Martin Brown

In article ,
Martin Brown wrote:
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*

Two 3 Kw kettles on the same extension should have blown the plug fuse and
quickly.

--
*Why is it considered necessary to screw down the lid of a coffin?

Dave Plowman London SW
To e-mail, change noise into sound.

Dave Plowman (News) wrote:

Two 3 Kw kettles on the same extension should have blown the plug fuse and
quickly.

A 13A fuse is required to carry 1.6x the rated current without blowing,
and only required to blow within 30 minutes for 1.9x rated current, so
whether, or how quickly it should blow, depends on the duty cycle of the
two kettles ...

On 15/03/2012 17:45, Dave Plowman (News) wrote:
In ,
Martin wrote:

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*

Two 3 Kw kettles on the same extension should have blown the plug fuse and
quickly.

Not quickly enough! About 10 minutes continuous use I would guess and
kettles tend to get used with only a small amount of overlap apart from
at the beginning when they boil both to get started. I can assure you
the 13A plug fuse did not blow in the time the water took to boil.

The fuse also recovers from thermal stress much faster than the bulky
reel of wound up and increasingly hotter cable.

I suspect part of the problem *IS* that people think the fuse will
always protect them if they are doing something wrong.

--
Regards,
Martin Brown

Martin Brown wrote:
On 15/03/2012 17:45, Dave Plowman (News) wrote:
In ,
Martin wrote:

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*

Two 3 Kw kettles on the same extension should have blown the plug fuse
and
quickly.

Not quickly enough! About 10 minutes continuous use I would guess and
kettles tend to get used with only a small amount of overlap apart from
at the beginning when they boil both to get started. I can assure you
the 13A plug fuse did not blow in the time the water took to boil.

The fuse also recovers from thermal stress much faster than the bulky
reel of wound up and increasingly hotter cable.

I suspect part of the problem *IS* that people think the fuse will
always protect them if they are doing something wrong.

Its very easy to melt a coiled up reel of cable at less than 13A.
Most of them say exactly that.


--
To people who know nothing, anything is possible.
To people who know too much, it is a sad fact
that they know how little is really possible -
and how hard it is to achieve it.

On Mar 16, 11:40*am, Martin Brown
wrote:
I suspect part of the problem *IS* that people think the fuse will
always protect them if they are doing something wrong.

I am surprised at how many people think a 13A fuse blows immediately
you go above it.

Equally, many do not understand the thermal insulation effect of a
rug, cushion or curtains on an extension lead. One reason I changed
all leads to 1.5mm H07RNF and 10A fuses, the rubber purely because it
is a little more robust to objects dropped on it (and at the time
cheap whereas now I notice it has jumped in price).

No idea if a fridge/freezer inrush mandates 13A over 10A or 7A;
standard fuse sizes are 3A 5A 13A. A lot of cheap consumer products
seem to be using internal components as the fuse :-)

Cheapest is education.

On 16/03/2012 11:40, Martin Brown wrote:
On 15/03/2012 17:45, Dave Plowman (News) wrote:
In ,
Martin wrote:

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*

Two 3 Kw kettles on the same extension should have blown the plug fuse
and
quickly.

Not quickly enough! About 10 minutes continuous use I would guess and
kettles tend to get used with only a small amount of overlap apart from
at the beginning when they boil both to get started. I can assure you
the 13A plug fuse did not blow in the time the water took to boil.

If there is only a small overlap in use then you would not really expect
the fuse to blow. That is diversity in action for you ;-)

The fuse also recovers from thermal stress much faster than the bulky
reel of wound up and increasingly hotter cable.

Its reaction is also as fast as its recovery though...

However the cable heating aspect is not really something you can expect
a fuse to do anything about, since it needs to be sized to provide
adequate fault protection for the cable in the first place, and overload
protection for the *maximum* rating of the cable in the second place.
However with a fully or partially wound lead you will not get anywhere
close to the maximum load before it overheats. You ideally need an
additional thermal protection mechanism in the drum of the lead itself
to cope with this.

I suspect part of the problem *IS* that people think the fuse will
always protect them if they are doing something wrong.

Possibly... many don't understand that its there primarily for fault
protection any not overload. The first its very good at, the second its
"ok" at in severe cases, but a bit patchy in the moderate cases.

--
Cheers,

John.

/================================================== ===============\
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| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On Thu, 15 Mar 2012 15:36:30 +0000, 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*

I am inclined to the view now that they should include a thermal cutout!
The clear warning on the reel has little or no effect on most folk

Similar story, this time a conveyer type toaster in the breakfast room
of a Premier Inn. Wound-up extention cable under table geting
noticably hot.

I told the maître d’hôtel (joke) that it was dangerous and needed
unwinding, and that I was an electrical engineer (a lie) and knew
about such things.

It was still there the next morning.





--
Graham.
%Profound_observation%

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.

David

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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|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

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 15/03/2012 13:42, Fred wrote:
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?

The answer is both, and also "heat"...

The longer the lead then the more voltage drop. May not be a huge
problem for many tools (power tools run a bit slower and with a bit less
oomph), but some kit may get upset (things with induction motors that
may stall on startup, or run but attempt to compensate for lack of volts
by drawing more current, and then overheating)

The second issue is fault current, or to be more accurate lack of it.
Long leads will have a higher earth loop impedance, and also a lower
prospective short circuit current. So when something goes pair shaped
the fuse in the lead takes longer to operate, or in the worst case, does
not operate at all in a sensible time. Making sure its fed from a RCD
protected socket is obviously a "good thing" (tm).

Lastly, heat. Long leads can only take a small proportion of their full
load when wound. Hence for big loads at moderate distances, you may find
yourself having to unwind a rats nest of cable to use it safely.

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.

Either that, or the flex has broken and gone intermittent at the ends
where it bends a lot.

The socket terminals might allow a bit of cleaning and bending to get a
better grip. The flex can have the first and last metre cut off and be
re-terminated to get rid of the dodgy bits.

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?

Depends on the loads you need to run partly. If you are doing big ones
at moderate distance, or ones for which voltage drop is going to be a
problem, then it may be worth it.

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.



--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On Thu, 15 Mar 2012 13:42:47 +0000, Fred wrote:

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?

Both but as others have said volt drop won't upset many things a
great deal. Fault currents could be an issue but as you will always
be running the extension via an RCD (won't you...) that isn't such a
problem either.

So it is time to buy a new lead or leads.

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 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.

A little bell jingles that the length limits are something like that
so as not to have too much (FSVO "too much") volt drop at full load.

Is there any advantage to buying a short "caravan hook-up" cable to use
for lengths under 25m?

I have a couple of 25m "caravan hook up" cables, for several reasons:

The cable is bright orange.
The cable is nice and flexible and coils nicely.
They are 2.5mm^2 cross section.

It is quite chunky stuff to have a 13A plug attached, so I have 16A
IEE connectors and adapters to 13A, primary use is from the generator
but as the IEE's are bit more water resistant than a 13A the pressure
washer has an IEE plug on it.

Unless you are working outside in winter I wouldn't bother with
arctic flex, the caravan hook stuff handles well and doesn't fight
back a great deal even when near freezing.

--
Cheers
Dave.

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 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 Mar 15, 1:42*pm, Fred wrote:
Anyway, some of my tools have started switching on and off
intermittently when plugged into the lead

If the cable is ok & 1.25mm^2 you could just replace the rest...
- Check the plug & strain relief are ok
- Remove any reel, they invite coiled use to avoid a trip hazard only
to overheat
- Fit a new duraplug or generic rubber 2-way or 4-way socket strip

If the cable is not ok...
- Buy or make up a short lead (10m) and long lead (20m)
- Do not go so short you need to daisychain leads, that invites other
problems

Cable sizing...
- For 13A load IEE guidelines are 1.5mm^2 to 15m, 2.5mm^2 to 25m.
- The aim is to prevent sufficient voltage drop that operation of
equipment at the end of the lead is impeded (motor does not start,
sits there cooking) or a short circuit does not permit sufficient
current flow to blow a fuse (cable sits there melting, cable becomes
the fuse)
- Real world is it depends on what you are going to stick on the end
of it.

Fridge-freezer.
- A long extension lead may cause sufficient voltage drop to prevent
the compressor starting, ruining food or creating a fire hazard.
- However, 25m of 2.5mm^2 flex from a CU is no different to 25m of
2.5mm^2 flat-twin-&-earth from a CU. (The CPC is actually larger in
the former, but not my point).

Tumble dryer.
- A 3kW load that melts solid extension leads not fully unwound, or
equally just dumped on the floor.

Pressure washer with beefy 1.7kW induction motor.
- Despite the spec, 25m on 1.5mm^2 is fine because it is only a 7A
load and the motor is not likely to stall.

Battery charger & light, soldering iron 50m away in shed.
- Gets more interesting when you add a 3kW fan heater or big induction
motor saw.
- Reality is the longer the cable, the more permanent its
installation, the greater the risk of damage occurring.

Never forget the RCD and test it. Avoid reels, they seem to induce
people to keep cable wound up to avoid a trip hazard yet can create an
overheating risk. Not all extension reels have thermal cutouts and
quality of stuff these days is a bit hit n miss. Warranty claim after
the carpet has a reel shaped burn in it is not going to go down
well :-)

On Mar 15, 1:42*pm, Fred wrote:
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

The downsides of long leads are outweighed by the upsides, and both
are minor issues anyway. Just fix whatever's broken on your lead.

If you replace plug or socket, cut 6" of flex off that end.


NT

"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.