Could someone remind me: is it dangerous to coil the lead for
Christmas tree lights? I know in general any electrical cord should
be fully unwound but is this a factor where low currents are involved?

On 16/12/2022 14:57, Scott wrote:
> Could someone remind me: is it dangerous to coil the lead for
> Christmas tree lights? I know in general any electrical cord should
> be fully unwound but is this a factor where low currents are involved?

Depends on the cable. If you're running a cable near its current limit,
it shouldn't be coiled but if (say) you're putting 1 amp or less through
a cable capable of carrying 13 amps, it doesn't really matter.
--
Cheers,
Roger

On Fri, 16 Dec 2022 16:04:49 +0000, Roger Mills
<mills37.fslife@gmail.com> wrote:

>On 16/12/2022 14:57, Scott wrote:
>> Could someone remind me: is it dangerous to coil the lead for
>> Christmas tree lights? I know in general any electrical cord should
>> be fully unwound but is this a factor where low currents are involved?
>
>Depends on the cable. If you're running a cable near its current limit,
>it shouldn't be coiled but if (say) you're putting 1 amp or less through
>a cable capable of carrying 13 amps, it doesn't really matter.

It's a very thin cable energised at 24 Volts so I suppose the current
is multiplied by 10. Safer not to coil it up I suppose in case it
heats up?

On Sat, 17 Dec 2022 04:04:40 +1100, Scott <newsgroups@gefion.myzen.co.uk>
wrote:

> On Fri, 16 Dec 2022 16:04:49 +0000, Roger Mills
> <mills37.fslife@gmail.com> wrote:
>
>> On 16/12/2022 14:57, Scott wrote:
>>> Could someone remind me: is it dangerous to coil the lead for
>>> Christmas tree lights? I know in general any electrical cord should
>>> be fully unwound but is this a factor where low currents are involved?
>>
>> Depends on the cable. If you're running a cable near its current limit,
>> it shouldn't be coiled but if (say) you're putting 1 amp or less through
>> a cable capable of carrying 13 amps, it doesn't really matter.
>
> It's a very thin cable energised at 24 Volts so I suppose the current
> is multiplied by 10. Safer not to coil it up I suppose in case it
> heats up?

Better to feel if it heats up and coil it if it doesn't.

On 16/12/2022 17:04, Scott wrote:
> On Fri, 16 Dec 2022 16:04:49 +0000, Roger Mills
> <mills37.fslife@gmail.com> wrote:
>
>> On 16/12/2022 14:57, Scott wrote:
>>> Could someone remind me: is it dangerous to coil the lead for
>>> Christmas tree lights? I know in general any electrical cord should
>>> be fully unwound but is this a factor where low currents are involved?
>>
>> Depends on the cable. If you're running a cable near its current limit,
>> it shouldn't be coiled but if (say) you're putting 1 amp or less through
>> a cable capable of carrying 13 amps, it doesn't really matter.
>
> It's a very thin cable energised at 24 Volts so I suppose the current
> is multiplied by 10. Safer not to coil it up I suppose in case it
> heats up?

LED lights or incandescent?

--
Cheers,

John.

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

On 16/12/2022 14:57, Scott wrote:
> Could someone remind me: is it dangerous to coil the lead for
> Christmas tree lights? I know in general any electrical cord should
> be fully unwound but is this a factor where low currents are involved?

It's a matter of how well they can dissipate heat, the actual coiling
makes no difference, if the coil is loose, with air able to easily
circulate around the cable to cool it. What cause is the heat, is how
closely the current flow, is to the current rating of the cable.

On Fri, 16 Dec 2022 19:12:44 +0000, Harry Bloomfield Esq
<a@harrym1byt.plus.com> wrote:

>On 16/12/2022 14:57, Scott wrote:
>> Could someone remind me: is it dangerous to coil the lead for
>> Christmas tree lights? I know in general any electrical cord should
>> be fully unwound but is this a factor where low currents are involved?
>
>It's a matter of how well they can dissipate heat, the actual coiling
>makes no difference, if the coil is loose, with air able to easily
>circulate around the cable to cool it. What cause is the heat, is how
>closely the current flow, is to the current rating of the cable.

Maybe I am completely misunderstanding this but I thought the coil
created an electromagnet and this was the concern.

On Sat, 17 Dec 2022 06:00:58 +1100, chop <chop654@gmail.com> wrote:

>On Sat, 17 Dec 2022 04:04:40 +1100, Scott <newsgroups@gefion.myzen.co.uk>
>wrote:
>
>> On Fri, 16 Dec 2022 16:04:49 +0000, Roger Mills
>> <mills37.fslife@gmail.com> wrote:
>>
>>> On 16/12/2022 14:57, Scott wrote:
>>>> Could someone remind me: is it dangerous to coil the lead for
>>>> Christmas tree lights? I know in general any electrical cord should
>>>> be fully unwound but is this a factor where low currents are involved?
>>>
>>> Depends on the cable. If you're running a cable near its current limit,
>>> it shouldn't be coiled but if (say) you're putting 1 amp or less through
>>> a cable capable of carrying 13 amps, it doesn't really matter.
>>
>> It's a very thin cable energised at 24 Volts so I suppose the current
>> is multiplied by 10. Safer not to coil it up I suppose in case it
>> heats up?
>
>Better to feel if it heats up and coil it if it doesn't.

See my post to Harry but I may be mistaken here.

On 16/12/2022 19:17, Scott wrote:
> Maybe I am completely misunderstanding this but I thought the coil
> created an electromagnet and this was the concern.

Many do believe that, but it is wrong. The electromagnet (inductance)
heating only happens, where there is a single core, looped through a
ferrous metal. Where there is both L and N in one cable (flow and
return) they cancel each other out, which is why they can get away with
metal cable reels.

On Sat, 17 Dec 2022 06:17:33 +1100, Scott <newsgroups@gefion.myzen.co.uk>
wrote:

> On Fri, 16 Dec 2022 19:12:44 +0000, Harry Bloomfield Esq
> <a@harrym1byt.plus.com> wrote:
>
>> On 16/12/2022 14:57, Scott wrote:
>>> Could someone remind me: is it dangerous to coil the lead for
>>> Christmas tree lights? I know in general any electrical cord should
>>> be fully unwound but is this a factor where low currents are involved?
>>
>> It's a matter of how well they can dissipate heat, the actual coiling
>> makes no difference, if the coil is loose, with air able to easily
>> circulate around the cable to cool it. What cause is the heat, is how
>> closely the current flow, is to the current rating of the cable.
>
> Maybe I am completely misunderstanding this

Yes you did.

> but I thought the coil
> created an electromagnet and this was the concern.

No.

On Sat, 17 Dec 2022 06:52:43 +1100, chop <chop654@gmail.com> wrote:

>On Sat, 17 Dec 2022 06:17:33 +1100, Scott <newsgroups@gefion.myzen.co.uk>
>wrote:
>
>> On Fri, 16 Dec 2022 19:12:44 +0000, Harry Bloomfield Esq
>> <a@harrym1byt.plus.com> wrote:
>>
>>> On 16/12/2022 14:57, Scott wrote:
>>>> Could someone remind me: is it dangerous to coil the lead for
>>>> Christmas tree lights? I know in general any electrical cord should
>>>> be fully unwound but is this a factor where low currents are involved?
>>>
>>> It's a matter of how well they can dissipate heat, the actual coiling
>>> makes no difference, if the coil is loose, with air able to easily
>>> circulate around the cable to cool it. What cause is the heat, is how
>>> closely the current flow, is to the current rating of the cable.
>>
>> Maybe I am completely misunderstanding this
>
>Yes you did.
>
>> but I thought the coil
>> created an electromagnet and this was the concern.
>
>No.

I was discombobulated.

On 16/12/2022 19:29, Harry Bloomfield Esq wrote:
> On 16/12/2022 19:17, Scott wrote:
>> Maybe I am completely misunderstanding this but I thought the coil
>> created an electromagnet and this was the concern.
>
> Many do believe that, but it is wrong. The electromagnet (inductance)
> heating only happens, where there is a single core, looped through a
> ferrous metal. Where there is both L and N in one cable (flow and
> return) they cancel each other out, which is why they can get away with
> metal cable reels.
>
>

I do believe that John Ward made a video of this "inductance" with live
and neutral though different holes into ferrous metal and was unable to
create hardly heat at all - even with a 100A load.

On 16/12/2022 17:04, Scott wrote:
> On Fri, 16 Dec 2022 16:04:49 +0000, Roger Mills
> <mills37.fslife@gmail.com> wrote:
>
>> On 16/12/2022 14:57, Scott wrote:
>>> Could someone remind me: is it dangerous to coil the lead for
>>> Christmas tree lights? I know in general any electrical cord should
>>> be fully unwound but is this a factor where low currents are involved?
>>
>> Depends on the cable. If you're running a cable near its current limit,
>> it shouldn't be coiled but if (say) you're putting 1 amp or less through
>> a cable capable of carrying 13 amps, it doesn't really matter.
>
> It's a very thin cable energised at 24 Volts so I suppose the current
> is multiplied by 10. Safer not to coil it up I suppose in case it
> heats up?

Energised at 24V

So that is a 24V supply

What does the PSU that supplies the lights say?

Something like 24VA? so that is one amp.

Harry Bloomfield Esq <a@harrym1byt.plus.com> wrote:
> On 16/12/2022 19:17, Scott wrote:
> > Maybe I am completely misunderstanding this but I thought the coil
> > created an electromagnet and this was the concern.
>
> Many do believe that, but it is wrong. The electromagnet (inductance)
> heating only happens, where there is a single core, looped through a
> ferrous metal. Where there is both L and N in one cable (flow and
> return) they cancel each other out, which is why they can get away with
> metal cable reels.
>
If it's 24v it's almost certainly DC anyway so inductance is irrelevant.

--
Chris Green
·

On Fri, 16 Dec 2022 20:22:38 +0000, ARW
<adamwadsworth@blueyonder.co.uk> wrote:

>On 16/12/2022 17:04, Scott wrote:
>> On Fri, 16 Dec 2022 16:04:49 +0000, Roger Mills
>> <mills37.fslife@gmail.com> wrote:
>>
>>> On 16/12/2022 14:57, Scott wrote:
>>>> Could someone remind me: is it dangerous to coil the lead for
>>>> Christmas tree lights? I know in general any electrical cord should
>>>> be fully unwound but is this a factor where low currents are involved?
>>>
>>> Depends on the cable. If you're running a cable near its current limit,
>>> it shouldn't be coiled but if (say) you're putting 1 amp or less through
>>> a cable capable of carrying 13 amps, it doesn't really matter.
>>
>> It's a very thin cable energised at 24 Volts so I suppose the current
>> is multiplied by 10. Safer not to coil it up I suppose in case it
>> heats up?
>
>Energised at 24V
>
>So that is a 24V supply
>
>What does the PSU that supplies the lights say?
>
>Something like 24VA? so that is one amp.
>
6VA. I assume this means a current of 0.25 amps. To go back to
Roger's comment, I have no idea what the cable is capable of carrying.
Does this mean I should not create a coil just in case or will it
never be an issue for 0.25 amps?

On Sat, 17 Dec 2022 08:16:06 +1100, Scott <newsgroups@gefion.myzen.co.uk>
wrote:

> On Fri, 16 Dec 2022 20:22:38 +0000, ARW
> <adamwadsworth@blueyonder.co.uk> wrote:
>
>> On 16/12/2022 17:04, Scott wrote:
>>> On Fri, 16 Dec 2022 16:04:49 +0000, Roger Mills
>>> <mills37.fslife@gmail.com> wrote:
>>>
>>>> On 16/12/2022 14:57, Scott wrote:
>>>>> Could someone remind me: is it dangerous to coil the lead for
>>>>> Christmas tree lights? I know in general any electrical cord should
>>>>> be fully unwound but is this a factor where low currents are
>>>>> involved?
>>>>
>>>> Depends on the cable. If you're running a cable near its current
>>>> limit,
>>>> it shouldn't be coiled but if (say) you're putting 1 amp or less
>>>> through
>>>> a cable capable of carrying 13 amps, it doesn't really matter.
>>>
>>> It's a very thin cable energised at 24 Volts so I suppose the current
>>> is multiplied by 10. Safer not to coil it up I suppose in case it
>>> heats up?
>>
>> Energised at 24V
>>
>> So that is a 24V supply
>>
>> What does the PSU that supplies the lights say?
>>
>> Something like 24VA? so that is one amp.
>>
> 6VA. I assume this means a current of 0.25 amps. To go back to
> Roger's comment, I have no idea what the cable is capable of carrying.

Any normal cable can handle that fine without getting even warm.

> Does this mean I should not create a coil just in case or will it
> never be an issue for 0.25 amps?

No, any coil will be fine. Coil away.

On Fri, 16 Dec 2022 20:41:28 +0000, Chris Green <cl@isbd.net> wrote:

>Harry Bloomfield Esq <a@harrym1byt.plus.com> wrote:
>> On 16/12/2022 19:17, Scott wrote:
>> > Maybe I am completely misunderstanding this but I thought the coil
>> > created an electromagnet and this was the concern.
>>
>> Many do believe that, but it is wrong. The electromagnet (inductance)
>> heating only happens, where there is a single core, looped through a
>> ferrous metal. Where there is both L and N in one cable (flow and
>> return) they cancel each other out, which is why they can get away with
>> metal cable reels.
>>
>If it's 24v it's almost certainly DC anyway so inductance is irrelevant.

Can the term 'VA' be used for DC? I thought it applied to AC systems.

On 16/12/2022 21:44, Scott wrote:
> On Fri, 16 Dec 2022 20:41:28 +0000, Chris Green <cl@isbd.net> wrote:
>
>> Harry Bloomfield Esq <a@harrym1byt.plus.com> wrote:
>>> On 16/12/2022 19:17, Scott wrote:
>>>> Maybe I am completely misunderstanding this but I thought the coil
>>>> created an electromagnet and this was the concern.
>>>
>>> Many do believe that, but it is wrong. The electromagnet (inductance)
>>> heating only happens, where there is a single core, looped through a
>>> ferrous metal. Where there is both L and N in one cable (flow and
>>> return) they cancel each other out, which is why they can get away with
>>> metal cable reels.
>>>
>> If it's 24v it's almost certainly DC anyway so inductance is irrelevant.
>
> Can the term 'VA' be used for DC? I thought it applied to AC systems.
>
VA and Watts are the same in a DC circui, the real power and apparent
power is the same. In AC circuits voltage and current are not
necessarily in phase so VA is the apparent power and the real power will
be less depending on the circuit and the waveform.

On 16/12/2022 19:12, Harry Bloomfield Esq wrote:
> It's a matter of how well they can dissipate heat, the actual coiling
> makes no difference

The coiling is of course what makes the difference in its ability to
dissipate heat....

watts per square cm etc etc. coiling reduces thee number of square cm of
the overall volume of air being heated.

--
“Those who can make you believe absurdities, can make you commit
atrocities.”

― Voltaire, Questions sur les Miracles à M. Claparede, Professeur de
Théologie à Genève, par un Proposant: Ou Extrait de Diverses Lettres de
M. de Voltaire

On 16/12/2022 19:29, Harry Bloomfield Esq wrote:
> which is why they can get away with metal cable reels.
? Jesus Wept!
--
"Nature does not give up the winter because people dislike the cold."

― Confucius

Not usually. Is this the type of lights with the psu effects box using leds,
or the old screw in filament bulb sort?
I've never had any problems coiling either, but on the other hand you do
not want a tight bundle as if somebody trips over the wire you are likely to
get the whole tree on your head!
Also it goes without saying that cats can demolish trees and some animals
like nothing else but to chew the cables.
Brian

--

--:
This newsgroup posting comes to you directly from...
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briang1@blueyonder.co.uk
Blind user, so no pictures please
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"Scott" <newsgroups@gefion.myzen.co.uk> wrote in message
news:mm1pphpisftdrf0pmalka5gptmhril7di4@4ax.com...
> Could someone remind me: is it dangerous to coil the lead for
> Christmas tree lights? I know in general any electrical cord should
> be fully unwound but is this a factor where low currents are involved?

In most cases I've seen of problems with lights, its the power supply that
has gone down. I'd keep that well away from anything flammable as some are
truly cheap and cheerful, and also tend to radiate RF everywhere.

Brian

--

--:
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...
briang1@blueyonder.co.uk
Blind user, so no pictures please
Note this Signature is meaningless.!
"Scott" <newsgroups@gefion.myzen.co.uk> wrote in message
news:k29pph1195gutm6deb5kv4sjq24tltdehd@4ax.com...
> On Fri, 16 Dec 2022 16:04:49 +0000, Roger Mills
> <mills37.fslife@gmail.com> wrote:
>
>>On 16/12/2022 14:57, Scott wrote:
>>> Could someone remind me: is it dangerous to coil the lead for
>>> Christmas tree lights? I know in general any electrical cord should
>>> be fully unwound but is this a factor where low currents are involved?
>>
>>Depends on the cable. If you're running a cable near its current limit,
>>it shouldn't be coiled but if (say) you're putting 1 amp or less through
>>a cable capable of carrying 13 amps, it doesn't really matter.
>
> It's a very thin cable energised at 24 Volts so I suppose the current
> is multiplied by 10. Safer not to coil it up I suppose in case it
> heats up?

On Sat, 17 Dec 2022 10:07:29 -0000, "Brian Gaff"
<brian1gaff@gmail.com> wrote:

>Not usually. Is this the type of lights with the psu effects box using leds,
>or the old screw in filament bulb sort?
> I've never had any problems coiling either, but on the other hand you do
>not want a tight bundle as if somebody trips over the wire you are likely to
>get the whole tree on your head!
>Also it goes without saying that cats can demolish trees and some animals
>like nothing else but to chew the cables.
> Brian

It's a string of LED lights operating at 24 volts designed for use
outdoors, which is why the cord is so long. Given all the
uncertainties here, I think it would be best to randomise the cable
rather than coiling it up.

On Sat, 17 Dec 2022 10:11:47 -0000, "Brian Gaff"
<brian1gaff@gmail.com> wrote:

>In most cases I've seen of problems with lights, its the power supply that
>has gone down. I'd keep that well away from anything flammable as some are
>truly cheap and cheerful, and also tend to radiate RF everywhere.
>
Thanks. I'll find a non-combustible surface. Probably taken from the
world of cooking.

On 12/17/2022 5:53 AM, Scott wrote:
> On Sat, 17 Dec 2022 10:07:29 -0000, "Brian Gaff"
> <brian1gaff@gmail.com> wrote:
>
>> Not usually. Is this the type of lights with the psu effects box using leds,
>> or the old screw in filament bulb sort?
>> I've never had any problems coiling either, but on the other hand you do
>> not want a tight bundle as if somebody trips over the wire you are likely to
>> get the whole tree on your head!
>> Also it goes without saying that cats can demolish trees and some animals
>> like nothing else but to chew the cables.
>> Brian
>
> It's a string of LED lights operating at 24 volts designed for use
> outdoors, which is why the cord is so long. Given all the
> uncertainties here, I think it would be best to randomise the cable
> rather than coiling it up.
>

Some Christmas products, can be plugged serially (making
a longer chain), but the box may have a warning about
using too many of them in series like that.

Paul