I have a widget with a low voltage multicore cable, that I want to mount
outside. It'll be exposed to sunlight pretty much all the time. The cable
is black and I'd like it to be white.

So my options are either paint or replace the cable. According to this:
https://uk.prysmiangroup.com/sites/default/files/atoms/files/Painting%20of%20Cables%20%281%29.pdf
water-based paints are better because they won't leach plasticiser out of
the PVC.

But what kind of paint will be UV safe, will stick and not be likely to
flake off after a few years? (and that I don't need to buy by the gallon)

Or is there a good multicore cable available in white that will cope with
being outside? I need it to be screened and at least 5 cores (in a single
cable), and only need a few metres. I looked at various options for cat5
but there's not much in white (and most wanted to sell me 100m)

Thanks
Theo

On 26/04/2022 13:06, Theo wrote:
> I have a widget with a low voltage multicore cable, that I want to mount
> outside. It'll be exposed to sunlight pretty much all the time. The cable
> is black and I'd like it to be white.

Black can sometimes perform better than white if it is in full sun. It
stops the sunlight from penetrating into the plastic more efficiently.
>
> So my options are either paint or replace the cable. According to this:
> https://uk.prysmiangroup.com/sites/default/files/atoms/files/Painting%20of%20Cables%20%281%29.pdf
> water-based paints are better because they won't leach plasticiser out of
> the PVC.
>
> But what kind of paint will be UV safe, will stick and not be likely to
> flake off after a few years? (and that I don't need to buy by the gallon)

Whatever you paint it with will inevitably flake off after a while. The
cheapest water based matt white acrylic would be my choice.

> Or is there a good multicore cable available in white that will cope with
> being outside? I need it to be screened and at least 5 cores (in a single
> cable), and only need a few metres. I looked at various options for cat5
> but there's not much in white (and most wanted to sell me 100m)

You should be able to buy suitable outdoor UV stabilised signal cable
but they are going to want to sell you a roll of 50m, 100m or 500m.

--
Regards,
Martin Brown

On 26 Apr 2022 13:06:29 +0100 (BST), Theo
<theom+news@chiark.greenend.org.uk> wrote:

>
>I have a widget with a low voltage multicore cable, that I want to mount
>outside. It'll be exposed to sunlight pretty much all the time. The cable
>is black and I'd like it to be white.
>
>So my options are either paint or replace the cable. According to this:
>https://uk.prysmiangroup.com/sites/default/files/atoms/files/Painting%20of%20Cables%20%281%29.pdf
>water-based paints are better because they won't leach plasticiser out of
>the PVC.
>
>But what kind of paint will be UV safe, will stick and not be likely to
>flake off after a few years? (and that I don't need to buy by the gallon)
>
>Or is there a good multicore cable available in white that will cope with
>being outside? I need it to be screened and at least 5 cores (in a single
>cable), and only need a few metres. I looked at various options for cat5
>but there's not much in white (and most wanted to sell me 100m)
>
>Thanks
>Theo

Put it in trunking?

--
Chris

On Tue, 26 Apr 2022 13:39:20 +0100, Chris Hogg <me@privacy.net> wrote:

>On 26 Apr 2022 13:06:29 +0100 (BST), Theo
><theom+news@chiark.greenend.org.uk> wrote:
>
>>
>>I have a widget with a low voltage multicore cable, that I want to mount
>>outside. It'll be exposed to sunlight pretty much all the time. The cable
>>is black and I'd like it to be white.
>>
>>So my options are either paint or replace the cable. According to this:
>>https://uk.prysmiangroup.com/sites/default/files/atoms/files/Painting%20of%20Cables%20%281%29.pdf
>>water-based paints are better because they won't leach plasticiser out of
>>the PVC.
>>
>>But what kind of paint will be UV safe, will stick and not be likely to
>>flake off after a few years? (and that I don't need to buy by the gallon)
>>
>>Or is there a good multicore cable available in white that will cope with
>>being outside? I need it to be screened and at least 5 cores (in a single
>>cable), and only need a few metres. I looked at various options for cat5
>>but there's not much in white (and most wanted to sell me 100m)
>>
>>Thanks
>>Theo
>
>Put it in trunking?

I was thinking that too. The trunking is likely to be white.

On Tuesday, 26 April 2022 at 13:06:36 UTC+1, Theo wrote:
> I have a widget with a low voltage multicore cable, that I want to mount
> outside. It'll be exposed to sunlight pretty much all the time. The cable
> is black and I'd like it to be white.
>
> So my options are either paint or replace the cable. According to this:
> https://uk.prysmiangroup.com/sites/default/files/atoms/files/Painting%20of%20Cables%20%281%29.pdf
> water-based paints are better because they won't leach plasticiser out of
> the PVC.
>
> But what kind of paint will be UV safe, will stick and not be likely to
> flake off after a few years? (and that I don't need to buy by the gallon)
>
> Or is there a good multicore cable available in white that will cope with
> being outside? I need it to be screened and at least 5 cores (in a single
> cable), and only need a few metres. I looked at various options for cat5
> but there's not much in white (and most wanted to sell me 100m)
>
> Thanks
> Theo

Outdoor PVC cable should be black, the black pigment blocks UV that eventually destroys the cable.
The paint to use on pvc cable is household gloss topcoat, NOT water based. It adheres better than anything else.

On 26/04/2022 13:06, Theo wrote:
> I have a widget with a low voltage multicore cable, that I want to mount
> outside. It'll be exposed to sunlight pretty much all the time. The cable
> is black and I'd like it to be white.
>
> So my options are either paint or replace the cable. According to this:
> https://uk.prysmiangroup.com/sites/default/files/atoms/files/Painting%20of%20Cables%20%281%29.pdf
> water-based paints are better because they won't leach plasticiser out of
> the PVC.
>
> But what kind of paint will be UV safe, will stick and not be likely to
> flake off after a few years? (and that I don't need to buy by the gallon)
>
> Or is there a good multicore cable available in white that will cope with
> being outside? I need it to be screened and at least 5 cores (in a single
> cable), and only need a few metres. I looked at various options for cat5
> but there's not much in white (and most wanted to sell me 100m)

Can you get white heatshrink sleeving of the correct size? Polyolefin is
considered UV resistant.

In message <s4qf6hd4990bei1ah378h9tufrikgemrm5@4ax.com>, Scott
<newsgroups@gefion.myzen.co.uk> writes
>On Tue, 26 Apr 2022 13:39:20 +0100, Chris Hogg <me@privacy.net> wrote:
>
>>On 26 Apr 2022 13:06:29 +0100 (BST), Theo
>><theom+news@chiark.greenend.org.uk> wrote:
>>
>>>
>>>I have a widget with a low voltage multicore cable, that I want to mount
>>>outside. It'll be exposed to sunlight pretty much all the time. The cable
>>>is black and I'd like it to be white.
>>>
>>>So my options are either paint or replace the cable. According to this:
>>>https://uk.prysmiangroup.com/sites/default/files/atoms/files/Painting%
>>>20of%20Cables%20%281%29.pdf
>>>water-based paints are better because they won't leach plasticiser out of
>>>the PVC.
>>>
>>>But what kind of paint will be UV safe, will stick and not be likely to
>>>flake off after a few years? (and that I don't need to buy by the gallon)
>>>
>>>Or is there a good multicore cable available in white that will cope with
>>>being outside? I need it to be screened and at least 5 cores (in a single
>>>cable), and only need a few metres. I looked at various options for cat5
>>>but there's not much in white (and most wanted to sell me 100m)
>>>
>>>Thanks
>>>Theo
>>
>>Put it in trunking?
>
>I was thinking that too. The trunking is likely to be white.

Offcut of Speedfit 10mm pipe?

--
Tim Lamb

Tim Lamb <tim@marfordfarm.demon.co.uk> wrote:
> In message <s4qf6hd4990bei1ah378h9tufrikgemrm5@4ax.com>, Scott
> <newsgroups@gefion.myzen.co.uk> writes
> >On Tue, 26 Apr 2022 13:39:20 +0100, Chris Hogg <me@privacy.net> wrote:
> >>Put it in trunking?
> >
> >I was thinking that too. The trunking is likely to be white.
>
> Offcut of Speedfit 10mm pipe?

It's a wire drop, and I want to make it less conspicuous against a white
background. Trunking or pipework would do the opposite :-)

(and being a wire drop it needs to turn awkward angles that conduit wouldn't
handle)

Theo

Fredxx <fredxx@spam.uk> wrote:
> Can you get white heatshrink sleeving of the correct size? Polyolefin is
> considered UV resistant.

That's a good idea, I hadn't thought of that. Apparently polyolefin is only
UV safe in black form, so back to where we started. FEP is also UV safe,
but all the FEP I can see on ebay is clear. So not sure what other options
there might be...

Theo

Animal <tabbypurr@gmail.com> wrote:
> Outdoor PVC cable should be black, the black pigment blocks UV that
> eventually destroys the cable. The paint to use on pvc cable is household
> gloss topcoat, NOT water based. It adheres better than anything else.

Thanks. So I suppose a black cable painted white is more UV safe than a
white cable. And maybe a light coating of spray paint is less harmful to
the PVC than a thick coating of gloss? The PDF I linked says even short
term exposure to naptha (in gloss, eg Dulux Trade) can damage the PVC.

Theo

On 26/04/2022 20:14, Theo wrote:
> Animal <tabbypurr@gmail.com> wrote:
>> Outdoor PVC cable should be black, the black pigment blocks UV that
>> eventually destroys the cable. The paint to use on pvc cable is household
>> gloss topcoat, NOT water based. It adheres better than anything else.
>
> Thanks. So I suppose a black cable painted white is more UV safe than a
> white cable. And maybe a light coating of spray paint is less harmful to
> the PVC than a thick coating of gloss? The PDF I linked says even short
> term exposure to naptha (in gloss, eg Dulux Trade) can damage the PVC.

Although that is true it is also the case that a small amout of surface
damage is necessary to give the paint a key. I don't know if gloss paint
will cause permanent damage to your particular cable. The makers will
tend to err on the side of caution especially if it is safety critical
or might be fire safe compromised by a gloss paint coat.

The other trick you might be able to use is run the cable at roof line
level out of sight and then down behind a drainpipe which is how my
fibre installation was done by a very helpful BT engineer.

--
Regards,
Martin Brown

On 26/04/2022 20:06, Theo wrote:
> Fredxx <fredxx@spam.uk> wrote:
>> Can you get white heatshrink sleeving of the correct size? Polyolefin is
>> considered UV resistant.
>
> That's a good idea, I hadn't thought of that. Apparently polyolefin is only
> UV safe in black form, so back to where we started. FEP is also UV safe,
> but all the FEP I can see on ebay is clear. So not sure what other options
> there might be...

Where did you find that claim? I read that Polyolefin was UV resistant
and articles I read didn't mention colour.

This claims to be UV resistant:
https://www.cablecraft.co.uk/birch-valley-3-2-6-4mm-white-pvc-heat-shrink-sleeving-250m-coil

On 26/04/2022 13:06, Theo wrote:
> I have a widget with a low voltage multicore cable, that I want to mount
> outside. It'll be exposed to sunlight pretty much all the time. The cable
> is black and I'd like it to be white.
>
> So my options are either paint or replace the cable. According to this:
> https://uk.prysmiangroup.com/sites/default/files/atoms/files/Painting%20of%20Cables%20%281%29.pdf
> water-based paints are better because they won't leach plasticiser out of
> the PVC.
>
> But what kind of paint will be UV safe, will stick and not be likely to
> flake off after a few years? (and that I don't need to buy by the gallon)
>
> Or is there a good multicore cable available in white that will cope with
> being outside? I need it to be screened and at least 5 cores (in a single
> cable), and only need a few metres. I looked at various options for cat5
> but there's not much in white (and most wanted to sell me 100m)
>
> Thanks
> Theo

Gently sand the cable so the surface is rough (pull it through rolled up
sandpaper). Apply white primer and leave to dry. Apply white oil-based
matt paint. The easiest way is to suspend the cable like a washing line
at a convenient height for handling. I've done this many times for
customers.

Bill

williamwright <wrightsaerials@f2s.com> wrote
> Theo wrote

>> I have a widget with a low voltage multicore cable, that I want to mount
>> outside. It'll be exposed to sunlight pretty much all the time. The
>> cable
>> is black and I'd like it to be white.
>> So my options are either paint or replace the cable. According to
>> this:
>> https://uk.prysmiangroup.com/sites/default/files/atoms/files/Painting%20of%20Cables%20%281%29.pdf
>> water-based paints are better because they won't leach plasticiser out
>> of
>> the PVC.
>> But what kind of paint will be UV safe, will stick and not be likely to
>> flake off after a few years? (and that I don't need to buy by the
>> gallon)
>> Or is there a good multicore cable available in white that will cope
>> with
>> being outside? I need it to be screened and at least 5 cores (in a
>> single
>> cable), and only need a few metres. I looked at various options for
>> cat5
>> but there's not much in white (and most wanted to sell me 100m)
>> Thanks
>> Theo
>
> Gently sand the cable so the surface is rough (pull it through rolled up
> sandpaper). Apply white primer and leave to dry. Apply white oil-based
> matt paint. The easiest way is to suspend the cable like a washing line
> at a convenient height for handling. I've done this many times for
> customers.

What does it do for the life of the cable ?

On Tuesday, 26 April 2022 at 13:06:36 UTC+1, Theo wrote:
> I have a widget with a low voltage multicore cable, that I want to mount
> outside. It'll be exposed to sunlight pretty much all the time. The cable
> is black and I'd like it to be white.
>
> So my options are either paint or replace the cable. According to this:
> https://uk.prysmiangroup.com/sites/default/files/atoms/files/Painting%20of%20Cables%20%281%29.pdf
> water-based paints are better because they won't leach plasticiser out of
> the PVC.
>
> But what kind of paint will be UV safe, will stick and not be likely to
> flake off after a few years? (and that I don't need to buy by the gallon)
>
> Or is there a good multicore cable available in white that will cope with
> being outside? I need it to be screened and at least 5 cores (in a single
> cable), and only need a few metres. I looked at various options for cat5
> but there's not much in white (and most wanted to sell me 100m)
>
> Thanks
> Theo
Call me cynical but I've often pulled out redundant PVC insulated 230v cables which had been clipped to a wall and painted over and found the cable perfectly serviceable despite years of years of use. I'm inclined to take the report as arse covering in extremis. Your description of low voltage might need some thought. Do you actually mean extra low for security or comms circuit? In which case I really can't see any cause for concern about the effects of paint.

On 27/04/2022 05:44, John J wrote:

> Call me cynical but I've often pulled out redundant PVC insulated 230v cables which had been clipped to a wall and painted over and found the cable perfectly serviceable despite years of years of use.

I the past year I removed mains cable (grey twin and earth) clipped to
an outside south facing wall and found the insulation to be brittle and
cracked. I was told that the light it was connected to was installed
approx 5 years before. There was a "quality" connection to the short
length of cable that often comes with outside lights - possible a whole
roll of insulation tape had been used :)

When removing a fallen aerial from my roof the white coax (PF100? with
copper foil) looked to be in very good condition and that had be exposed
to the elements for 10+ years. It was possibly less flexible than the
length in the loft. The replacement aerial is now located in the loft.

--
mailto : news {at} admac {dot} myzen {dot} co {dot} uk

John J <johnjessop46@gmail.com> wrote:
> Call me cynical but I've often pulled out redundant PVC insulated 230v
> cables which had been clipped to a wall and painted over and found the
> cable perfectly serviceable despite years of years of use. I'm inclined
> to take the report as arse covering in extremis. Your description of low
> voltage might need some thought. Do you actually mean extra low for
> security or comms circuit? In which case I really can't see any cause for
> concern about the effects of paint.

'Low voltage' in the domestic sense, not in the power company sense. I'm
not likely to be clipping 11kV wires to my wall :-)

This one has to carry 5V at 3mA, so I think that counts as 'low'. It's for
a wind sensor, so basically all it does is (virtually) go 'click' every
rotation. But being a wind sensor the cable drop is likely to get buffetted
around, which means some degree of long term flexibility is required. An
embrittled cable might be OK if rigidly clipped to a wall, but not if flexed
by gusts once a minute.

(I'm possibly overthinking this as the innards might die before the cable
does, but thought it was an interesting general question)

Theo

On 27/04/2022 11:45, Theo wrote:
> John J <johnjessop46@gmail.com> wrote:
>> Call me cynical but I've often pulled out redundant PVC insulated 230v
>> cables which had been clipped to a wall and painted over and found the
>> cable perfectly serviceable despite years of years of use. I'm inclined
>> to take the report as arse covering in extremis. Your description of low
>> voltage might need some thought. Do you actually mean extra low for
>> security or comms circuit? In which case I really can't see any cause for
>> concern about the effects of paint.
>
> 'Low voltage' in the domestic sense, not in the power company sense. I'm
> not likely to be clipping 11kV wires to my wall :-)
>
> This one has to carry 5V at 3mA, so I think that counts as 'low'. It's for
> a wind sensor, so basically all it does is (virtually) go 'click' every
> rotation. But being a wind sensor the cable drop is likely to get buffetted
> around, which means some degree of long term flexibility is required. An
> embrittled cable might be OK if rigidly clipped to a wall, but not if flexed
> by gusts once a minute.

It is really only going to get bufetted where it goes up the pole to the
sensor. A few black cable ties ought to sort that out easily enough.
>
> (I'm possibly overthinking this as the innards might die before the cable
> does, but thought it was an interesting general question)

I have seen unprotected phone cable used outside still functioning long
after chunks of outer insulation had dropped off. It requires the inner
cable insulation to fail in addition before the signal is compromised.

--
Regards,
Martin Brown

On 27/04/2022 04:35, Rod Speed wrote:
>> Gently sand the cable so the surface is rough (pull it through rolled
>> up sandpaper). Apply white primer and leave to dry. Apply white
>> oil-based matt paint. The easiest way is to suspend the cable like a
>> washing line at a convenient height for handling. I've done this many
>> times for customers.
>
> What does it do for the life of the cable ?

It has no effect. I've gone back to them years later.

Bill

On Tuesday, 26 April 2022 at 20:14:17 UTC+1, Theo wrote:
> Animal <tabb...@gmail.com> wrote:
> > Outdoor PVC cable should be black, the black pigment blocks UV that
> > eventually destroys the cable. The paint to use on pvc cable is household
> > gloss topcoat, NOT water based. It adheres better than anything else.
> Thanks. So I suppose a black cable painted white is more UV safe than a
> white cable. And maybe a light coating of spray paint is less harmful to
> the PVC than a thick coating of gloss? The PDF I linked says even short
> term exposure to naptha (in gloss, eg Dulux Trade) can damage the PVC.
>
> Theo

it doesn't harm it, it bonds well.

On 28/04/2022 05:52, Animal wrote:
> On Tuesday, 26 April 2022 at 20:14:17 UTC+1, Theo wrote:
>> Animal <tabb...@gmail.com> wrote:
>>> Outdoor PVC cable should be black, the black pigment blocks UV that
>>> eventually destroys the cable. The paint to use on pvc cable is household
>>> gloss topcoat, NOT water based. It adheres better than anything else.
>> Thanks. So I suppose a black cable painted white is more UV safe than a
>> white cable. And maybe a light coating of spray paint is less harmful to
>> the PVC than a thick coating of gloss? The PDF I linked says even short
>> term exposure to naptha (in gloss, eg Dulux Trade) can damage the PVC.
>>
>> Theo
>
> it doesn't harm it, it bonds well.

How about wrapping the cable with white self-amalgamating tape?

--
Cheers,
Roger

On Thursday, 28 April 2022 at 15:33:18 UTC+1, Roger Mills wrote:
> On 28/04/2022 05:52, Animal wrote:
> > On Tuesday, 26 April 2022 at 20:14:17 UTC+1, Theo wrote:
> >> Animal <tabb...@gmail.com> wrote:

> >>> Outdoor PVC cable should be black, the black pigment blocks UV that
> >>> eventually destroys the cable. The paint to use on pvc cable is household
> >>> gloss topcoat, NOT water based. It adheres better than anything else.
> >> Thanks. So I suppose a black cable painted white is more UV safe than a
> >> white cable. And maybe a light coating of spray paint is less harmful to
> >> the PVC than a thick coating of gloss? The PDF I linked says even short
> >> term exposure to naptha (in gloss, eg Dulux Trade) can damage the PVC.
> >>
> >> Theo
> >
> > it doesn't harm it, it bonds well.
> How about wrapping the cable with white self-amalgamating tape?

Yes, or painting religious scenes all over it. You could... but why?