Painting outdoor cables

Black can sometimes perform better than white if it is in full sun. It stops the sunlight from penetrating into the plastic more efficiently.

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

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.

Put it in trunking?

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

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.

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

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

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

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

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.

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:

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

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.

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.

'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

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 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.

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

Bill

it doesn't harm it, it bonds well.

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