Shore Power Cable Coil

onesea

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I spent a whilst living in a caravan in a dark cold distant winter, I learned flaking my electric cable along the freshwater hose supplying my internal tank produced enough heat to defrost the fresh water hose some nights it didn’t freeze other nights it was a little earlier.
A little hose rerouting and more flex on less exposed hose and my supply hose rarely froze.
So yes coiled wires are not good, unless used correctly 😀
 

Refueler

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I spent a whilst living in a caravan in a dark cold distant winter, I learned flaking my electric cable along the freshwater hose supplying my internal tank produced enough heat to defrost the fresh water hose some nights it didn’t freeze other nights it was a little earlier.
A little hose rerouting and more flex on less exposed hose and my supply hose rarely froze.
So yes coiled wires are not good, unless used correctly 😀

Interesting .... I have standard sized cable to my boat at home and coils on the pontoon ..... in winter there can be over 1m of snow ... but during the accumulation of snow - I never see any evidence of coils melting snow ....

I have a long power cable from house laid out down to the 35ft Mobile Home - which then has lead off to BBQ area and decking - then to boat ... that power cable also never melts snow round it ...

I can only assume you may have had a lighter grade of cable that was warming up due to its smaller section ?
 

onesea

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Interesting .... I have standard sized cable to my boat at home and coils on the pontoon ..... in winter there can be over 1m of snow ... but during the accumulation of snow - I never see any evidence of coils melting snow ....

I have a long power cable from house laid out down to the 35ft Mobile Home - which then has lead off to BBQ area and decking - then to boat ... that power cable also never melts snow round it ...

I can only assume you may have had a lighter grade of cable that was warming up due to its smaller section ?
Or was pulling more current water pump, heating, hot water, fridge etc.
Maybe rarely froze was over statement. However I could run for day or 3 on internal tank so a little warmth/ break was enough to de thaw the pipe.
 

rotrax

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With 'True knowlege being the product of direct experience' I now state that my overlength shorepower cable used on our permanent berth has five 18 inch coils hanging on the boathook hook which is on my patent fitting on one of the backstays.

With the 2kw calorifier heating element on, the kettle and battery charger in action the coils do not warm up to the extent it can be felt by hand.

On some other berths there may be double the amount coiled. No problem.

Being aware of the theory, I have been dilligent and checked.
 

st599

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For the doubters check up on Toroidal transformers.
At large events you'll see the power leads unrolled from the drum and layed out in a figure 8. Reduces the heating, plus if someone pulls a cable it neatly uncoils.
 
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Stemar

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A 25m cable reel sold by Screwfix has this in the specs
Max. Power Unwound (W) 3120 W
Max. Power Wound (W) 720 W
Of course, that's quite tightly wound on a reel, with no air getting to the inner coils.

Our lead is also 50m, salvaged from a similar reel whose thermal cutout died, is now on a ply H shape that gives a lot more space for air to get to the cable, so I reckon I could double/triple the wound load quite happily, but I tend to take it off the H if I'm likely to use more than a few amps.
 

RunAgroundHard

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Thanks for all the replies. The reason I asked is that my short cable which had an integral electricity meter stopped working. I resorted to using my long cable, which is about 80' long; standard 16A cables with the blue style 16A, 3 x round pin shore power MxF connectors. I flaked the extra length on the deck instead of coiling.

I think the most important thing from this thread, thanks to wingcommander post 12, is that I need to get an electric kettle on the boat instead of boiling water in the gas stove, maybe a coffee maker, bread maker, air fryer and microwave as well. Seriously, no space for all that stuff and I sail often, but the kettle is a good idea.

As always, thanks for the feedback, much appreciated.
 

Refueler

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I have to say a 240v Kettle is a must on my boats ...... once connected to shore - on with the kettle.

Before leaving a berth and disconnecting ... I boil up and fill a pump flask ... so during a sail - I can make tea or coffee ... even a Pot Noodle if necessary without having to sort ....
 

mrangry

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At large events you'll see the power leads unrolled from the drum and layed out in a figure 8. Reduces the inductive load by having nearly equal and opposite loops, plus if someone pulls a cable it neatly uncoils.
They are uncoiled purely to prevent overheating as there is no issue with induction on a mains extension cord.
 

st599

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They are uncoiled purely to prevent overheating as there is no issue with induction on a mains extension cord.
I forgot that such cables often also carry data signals, which is the reason they suffer from inductance. I'll edit my post.
 
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