How to repair a two-core power cable?

We have a surround sound system and the sub is powered by a standard two-core cable (apologies if not the correct term, but just live/neutral). Anyway, Our new puppy has had a chew on it (thankfully caught before getting herself a bit of a shock), however, I want to fix it – what’s the easiest/neatest way of fixing? It’s a Sonos and it’s halfway down the cable so just shortening it isn’t an option.

Thank you (and bad dog)!

Flat two-core cable is available in any hardware store. Assuming you can get to the terminations in the sonos you can just replace it like for like. If not then you’ll need a junction box. Wagos seem to be the connection of choice these days, you can buy the connectors (like ‘choc-blocks’ but better) and the small enclosure to put them in.

Although this would also work fine.

What needs fixing?

Are the wires just exposed or properly broken?

As above, junction box of some kind is what you need.  I used an outdoor type one like this as it matched the cable colour and is water resistant and slimline

What needs fixing?

Are the wires just exposed or properly broken?

Wires just exposed.

Multi – where did you get that from? That’s the sort of neat solution I had been hoping for!

1. Strip back to non chewed wires on both sides.

2. Slide on some appropriately sized heat shrink for both the flex and for each individual core.

3. Twist up each core (4 of them).

4. Twist left over right and then backwards right over left to joint the wires securely.

5. Solder the joint.

6. Heat shrink each core.

7. Heatshrink the whole repair.

As per daffy…you can even buy heat shrink connectors with the solder already within them.  Much neater for a small cable than the big connection blocks above:

Like this with some black heat shrink over the top if you want to colour match.

in black if you’re posh.

Gobochul / mefty +1

The heat shrink + solder connectors are indeed brilliant witchcraft, for doing things like car wiring looms, but you’d still need some chunky heatshrink to cover them up afterwards and make it look neat (when making the joins, offset the cuts by the length of the heatshrink so they take up less space), the glue lined / waterproof stuff also provides a bit of mechanical strength so they can’t pull apart.

But ……. with my PAT tester hat on, I’d probably say it’s a fail because the insulation is still damaged and you can’t say for sure that the repair is better insulated than the original. Whereas a connection box is easy to check.

 in black if you’re posh.

That’s silver ducttape, which is often not-insulating because there’s an aluminized layer in there somewhere to reflect heat in HVAC ducts.

Gaffer tape tends to be electrically insulating because it’s intended to go on theater/set lighting.

Is it a mains flex (standard plug) or a transformer square brick style pub putting out low voltage?

It’s mains power 🙂

It a standard power cable isn’t it? No idea what they are called but the figure 8 ones.

Probably about a fiver? Or the official Sonos one;  https://www.sonos.com/en-gb/shop/power-cable-i

That’s silver ducttape, which is often not-insulating because there’s an aluminized layer in there somewhere to reflect heat in HVAC ducts.

News to me. I’ve never bodged a mains electrical repair with duct tape but that’s handy to know in case I’m ever tempted and have silver to hand so thanks!

It’s technically a “C7” but figure 8 lead will work in Google as well.

A couple of pound from Amazon/Ebay/Kenable.

Although the £25 Sonos one will probably widen the sound stage and tighten the bass.

Some fancy-dan repairs here!

What’s up with a choc-block and loads of insulating tape!?  🙂

What’s up with a choc-block and loads of insulating tape!? 

As the OP, it’s because I am anal about that sort of stuff – I can’t bear repairs like that.

News to me. I’ve never bodged a mains electrical repair with duct tape but that’s handy to know in case I’m ever tempted and have silver to hand so thanks!

It’s a blurry line, but generally “Duct” tape was designed for sealing ducts, so is horribly sticky, great on hard surfaces, and long lasting and a bit waterproof. Usually looks like plasticy ripstop.

“Gaffer” tape is a product from film and theater, gaffer is the job title for lighting technician*.  So it’s heat resistant, works on carpets as well, can be written on with sharpie, but also more temporary and doesn’t leave a residue. Usually looks like cloth.  I wouldn’t assume gaffer tape to be good insulation, but I’d not use duct tape anywhere where it being conductive might be an issue.

Electrical tape – shouldn’t actually be used for insulation. It’s insulating enough that a stray tail of it contacting something won’t cause a problem, but 0.1mm of PVC isn’t going to do the same job as ~2mm,  Fine for color coding wires, taping them together etc, but it’s not “insulation tape”.

*Gaffer = person with a gaff, gaff = big wooden pole, big wooden pole = the thing used to open the big skylights on the rooves of studios to let light in before high powered electrical lights were more common.

Have you looked in your drawer?  I looked in mine yesterday and there were two of those power cables along with some scart cables and Sky remote controls!

Have you looked in your drawer?  I looked in mine the yesterday and there were two of those power cables

I could have a look as I do have a big box of cables, old mobiles and other assorted gubbins, but on this model, the power input is on the base so it needs to be low-profile / angled to work.

https://www.kenable.co.uk/en/computer-cables-/power-cables/figure-8-mains-cables/8113-power-cord-uk-plug-to-right-angle-figure-8-fig-of-8-lead-cable-c7-18m-008113-5055383481132.html

Presumably if the puppy doesn’t have a frizzy fur-do the insulation has not been breached? Is the cable visible to the room? If not I’d be tempted to leave where it is as is.

What’s up with a choc-block and loads of insulating tape!? 🙂

When I was at the MOD we’d end up with 4 or 5 such repairs in a mains cable running to our camera shelters as they were repeatedly hit by fragments of whatever we happened to be blowing up. It was incredible the difference between explosive safety and electrical safety. Once we got contractorised there was a sudden concern for it and I spent a long time photographing all the many faults on site

Does the repair have to exist/show where the damage occurred? Cut the cable off nearer to the Sonos thing, so the repair is out of sight behind it? A new length of flex and a plug from the hardware shop job done.

I mean, obviously this should be repaired by a trained expert using armoured cable/ dog should have been trained properly before it was born/ Sonos is the wrong brand for some reason/ etc etc

gobuchul +1

Buy a compatible cable

gobuchul +1

Buy a compatible cable

TBF I think that is looking the best option – they aren’t that expensive – I just need to check that the one I get will work (as mentioned before, the power input is in the base) so I need a suitable cable.