Thread: Extension cord tangle

If you use a reel for your cord make sure you completely unwind it before using it so as to avoid creating a coil effect that can create heat. Use 2 x 25m lenghts

Originally Posted by Tiger

Dear all,

I'm getting tired of having to untangle the 50m extension cord that I'm using. Even when I'm fairly neat it still finds a way to tangle. With Father's Day coming up I'm thinking of asking for an extension cord which comes with its own winding mechanism and handle. Just wondering what others on the Forum do. Do you have yours on a roll, or have you solved the extension cord tangle puzzle? What length of cord do you find beneficial

I have two 20m jobbies on a wind-up roll. Can't say it's perfect but its OK. One is in the laundry; the other in the shed.

Just realised; this is a code violation - as I have not used the obligatory nail. The sole purpose of the cord is to hang on the nail.

I was going to get the same thing but then I read you should unwind it all the way when you used it. That made it seem like a waste of time.

Instead I have a 25m cord that I keep it well managed with a large Zenith utility hook ($6) that I mounted 2.0m off the ground. That makes it less turns and stops it getting tangled.

Tom

I've a 20m one on a reel. I never unwind it more than I need to and it never has got warm, let alone, hot.

I don't use big grunty tools, maybe it would if you ran a 3HP table saw off it.

I've got a few of different lengths: 5m 10m 20m. I only use the one/s that I need.

It also helps to learn how to roll and unroll a cord. There is a way I learned when I did a sound engineering course. The normal way people roll cords, they put a half twist in the cable every turn. Not only does this make the cord more likely to get tangled, it's also bad for the cable itself because it causes the wires inside the external sheath to move around. If you have a really old cord that has been wound this way constantly, it probably looks like an uncoiled spring (my dad has one like that )

If you lay the cord out on the driveway when its hot (a big ask in Victoria ) and let it heat up you will get rid of any tendence to tangle. Basically, you will 'relax' any kinks and twists.

Then coil it up using the "inside, outside" winding method. Don't wind it around an arm/elbow or make all the loops run the same way - this makes it tangle.
The "inside/outside" is a bit hard to explain, basically make all loops the same length. Take one natural loop (outside), then the next one twist the wrist 180 degrees at the top of the loop (inside). When you get it right you'll see that you will be making 6's and 9's instead of all 6's. Confused yet?
The coil won't tangle. Hang it on a twisted coathanger wire hook.

I don't like to use leads when they are coiled, they do heat up depending on the current drawn, and they will degrade internally even if you can't tell.
Eventually the insulation and wire will be affected by the heat and there will be some sort of drama. Hopefully you will have turfed the lead before this happes, but maybe not.

Apologies if you know about the coiling technique.

With apologies to those that already know all this stuff.

The coil or magnetic effect on cable warming depends on how many turns and how closely packed together the coils are. The overall magnetic heating effect for a 20m long cable carrying 10 A ranges from, virtually zero for fully uncoiled, to that approaching a 30w light globe for tightly coiled cable (~100W for a 50m cable!).

One aspect that many people don't appreciate is that as cables get older and plugs and sockets wear and corrode, they operate less efficiently and thereby hotter. This purely resistive heating effect can approach that or become greater than the magnetic effect even when the coil is unwound!

I have a 30m long 20 year old 10 A cable which has a straight resistance of 1.5 ohm which at 10 A would be dissipating about 150W. This is like having a 150W light globe buried inside the cable. Most of the additional resistance is often in the electrical connections so fitting new plugs and sockets can improve this down substantially.

Combine the "magnetic effect" with the "old cable resistive effect" at high current under a pile of sawdust and other combustibles then there is definitely a BIG problem. Usually the insulation melts and the fireworks start.

I personally use a range of cable lengths from 30m down. The most common one I use is a 10m long orange one made up from 15A cable and normal 10A plug and socket. I use this one more because it is more physically robust 10 A cable that its ability to handle higher currents.

G'Day All,

I used to have the cord tangle thing happening, until I was talking to a "sparkie" at work several years back and he showed me one of the best ways to roll a cord.

In the left hand (I'm right-handed) take the cord about a mtr from the plug, with the right hand start to make your first loop by bringing your hands together at about waist height. As your hands come together roll the cord between the thumb and fore finger, you should see the cord lay naturally into your left hand. Then seperate your hands letting the cord slip through your right hand and take another "bite".

It looks like a slow clapping motion, it took me a while to get the hang of it, but now I can roll the longest cords I have and I don't let anyone do them for me. The other thing is as the cord comes towards you it will naturally roll in the right motion you are looping to your holding hand.

I also use Savage's method. Or should that be "he uses mine" ??

One thing though, regardless of method: before coiling the cord should be run out in a more or less straight line! If 'tis all thrown into a heap (ala spaghetti tangle) many twists will transfer over into the coil.

Not only do these twists make the coil unwieldy but, as has been said, are not good for the cord in the long run.

Boy, you learn things all the time.
I have a 50 metre extension cord wound around one of the metal rolls that cords come on. I had a plug at one end, coming through the side of the roll and unwind it as much as I need. I had never noticed the cord to heat up, but am I right in thinking that it would have been, the more so the longer it was being used?:confused:
CJ

the "inside, outside" winding method

This is the way I do it. Any other way (sorry, that includes the other methods described above) naturally put a half twist for every loop. You know it does because you are rolling it in your fingers. With the roadies roll (my name for it) the half twist corrects itself.

The only downside of that method is when someone who doesn't know how to uncoil it tries to and they end up with a knot every couple of metres.

Also, once you have 'trained' the lead, you don't need to lay it out flat - it will naturally find it's shape.

Good stuff Bob, like your work.

Originally Posted by sea dragon

Boy, you learn things all the time.
I have a 50 metre extension cord wound around one of the metal rolls that cords come on. I had a plug at one end, coming through the side of the roll and unwind it as much as I need. I had never noticed the cord to heat up, but am I right in thinking that it would have been, the more so the longer it was being used?:confused:
CJ

It really depends what you are driving with the cord. A drill drawing 1 A would be OK to use continuously on such a set up but a device drawing 10 A will heat up the coil 10^2 or 100 times more. I

f you want to feel the heat your coil generates try powering an electic kettle (these things usually draw 8 to 10A (with the minimum amount of water in it and as soon as the coil starts to feel slightly warm turn it off. Remember if you can feel it heating up on the outside the inside wires will be significantly hotter.

Those metal roll things are particularly bad because they allow you to wind the coil quite tightly which further enhances the magnetic heating effect. The inner parts of the coil also cannot release the heat they generate so they get hottest.

I stronly recomend that you learn to roll your cables efficiently and that you buy several shorter cables of varying lengths, a 30, 20 10 and a couple of 5.
and never use a cable that is longer than needed.

or have your 50 cut down to a couple of shorter cables a 30 and a 20 perhaps.

and dont let the wife or kids near them

50 metres is a lot of cable to handle in one lump you don't need to be doing that unless you need to.

From time to time I handle lots of cable
I have been known to roll up 30 or 40 extension cables in a night and then theres the mic cables and the speaker cables.

I used hose reels at one time but found that they were too bulky and the can be hard on cables particulary the wire reels.

I reverse rolled, (thats the one where you twist each alternate loop) for a while until I sent a bloke to lay a 30 metre cable & he pulled the end thru the middle and I had to untangle 20 something knots out of the cable.
If you roll this way you must make sure that neither end finds its way thru the middle of the roll or tha whole thing will self knot.

I just flat roll these days, I roll anything less than 20 metres in loops about 600 across, longer than that quite a bit bigger.

it best to lay the lead out full length before rolling it up, that way the twists will fall off the end.

bigger leads I will often roll in loops on the floor after about 8 or 10 30m leads rolling in the hand gets a bit tyring.

always roll up from the same end and always the same size, the cable will almost roll its self if you dont upset it.

Yes leads do like a day in the sun, if you are short on sun lock them in the van for a hour or two parked in the sun, lay out and roll up while warm.

Many will say always roll from the plug end because then you know the lead isn't live. Big brother had a live 3 phase lead pull out of the plug while he was rolling it one day:eek: .... he always rolls from plug end

The only thing you should roll over your elbow is cheap rope and figure eight speaker wire.

BTW I do not believe a 10 amp 50 metre cable will pass current regs even when new, the earth resistance won't come up to spec.
Anything longer than 20 metre with 10 amp plugs in my opinion should be made on 15 amp cable and anything longre than 50 metre on 10 amp plugs should be made on 20 amp cable.

Have your cables tested at leats anualy.
I am constantly surprised how many faults I find when testing and tagging even on my own well maintained gear.

be kind to your cables.
cheers