12v Cable frugality

[Neeves]

I inherited rather long lengths of electrical cable with various coloured covers. The wiring is single copper wire about 1mm in diameter. It is in various colours, red, yellow, black.

I can think of no sensible use for the wiring, the house has been fully rewired, this inherited cable is not tinned and is a single wire (so prone to failure on a yacht - or so it is said). I have had the cable for years now and I may have found a use

namely

I do want to make up some extension leads for roving solar panels. Heavy duty cabling is expensive.

Can I bundle together, say 3 (or 5) lengths of red and 3 (or 5) lengths of black to make up an extension cable, say 10m long, with 3 (5) 'black' and 3 (5) 'red' copper wires soldered into an Anderson at each end - or is my frugality simply showing my ignorance.

I could measure and calculate the cross sectional area of the single wire, the copper core, to calculate the total area and determine the resultant cable's maximum usage.

Jonathan

 

[HughClayton]

The short answer is “yes you can”.

The slightly longer answer is that solid core wire doesn’t like to be flexed and you may find it frustrating when the solid cores fracture at the joins or terminations. You’ll also need to do a little light math to determine how many cores are needed for the size of panel.

I suspect that you’re likely to find that the cost of 2 core 2.5mm2 Oceanflex or similar is a small fraction of the cost of the panels and worth avoiding the aggravation.

 

[AngusMcDoon]

You could, but as you already know, solid core cable is prone to failure in any application where it moves. Soldered cable connections are also not reliable if they go in any crimp or clamp connector. 10m of proper solar cable with MC4 connectors crimped on will hardly break the bank.

 

[Neeves]

I accept the negativity - I'm trying to re-birth what I have.

I suppose send the redundant wire for scrap and start with fresh.

Jonathan

 

[Refueler]

Multiple leads to carry power ?

Have a gander at this mess ... the main +ve here is exactly that ... the white cables ....

It's not my work ! Its how the boat was setup by previous owners ... something that will take effort and time to sort out.

 

[NormanS]

I inherited rather long lengths of electrical cable with various coloured covers. The wiring is single copper wire about 1mm in diameter. It is in various colours, red, yellow, black.

I can think of no sensible use for the wiring, the house has been fully rewired, this inherited cable is not tinned and is a single wire (so prone to failure on a yacht - or so it is said). I have had the cable for years now and I may have found a use

namely

I do want to make up some extension leads for roving solar panels. Heavy duty cabling is expensive.

Can I bundle together, say 3 (or 5) lengths of red and 3 (or 5) lengths of black to make up an extension cable, say 10m long, with 3 (5) 'black' and 3 (5) 'red' copper wires soldered into an Anderson at each end - or is my frugality simply showing my ignorance.

I could measure and calculate the cross sectional area of the single wire, the copper core, to calculate the total area and determine the resultant cable's maximum usage.

Jonathan

I'm no electrical expert, but I wouldn't use single copper as a moveable extension lead. That's what multistrand is for.

 

[lustyd]

I bought a reel of black solar cable to make my extensions. You can’t plug MC4 cables backwards so no need to buy two colours and a reel is cheaper than cut cable. I have an Andersen one end and MC4s the other, then a bunch of varying length MC4 to MC4 so I can move each panel individually.

 

[Alex_Blackwood]

I inherited rather long lengths of electrical cable with various coloured covers. The wiring is single copper wire about 1mm in diameter. It is in various colours, red, yellow, black.

I can think of no sensible use for the wiring, the house has been fully rewired, this inherited cable is not tinned and is a single wire (so prone to failure on a yacht - or so it is said). I have had the cable for years now and I may have found a use

namely

I do want to make up some extension leads for roving solar panels. Heavy duty cabling is expensive.

Can I bundle together, say 3 (or 5) lengths of red and 3 (or 5) lengths of black to make up an extension cable, say 10m long, with 3 (5) 'black' and 3 (5) 'red' copper wires soldered into an Anderson at each end - or is my frugality simply showing my ignorance.

I could measure and calculate the cross sectional area of the single wire, the copper core, to calculate the total area and determine the resultant cable's maximum usage.

Jonathan

If you want yes, Then change your tally to the "Artful bodger"! As others have said not the right cable for the job, might work for a while. You will just have endless trouble with the odd core breaking, difficulty handling etc. Would make me scream if I saw a job like that! I would have to laugh, otherwise would just cry.
That's only my opinion though

 

[rogerthebodger]

When I wired up my boat DistantShaws I used panel wiring with the main wiring being 1.5 ,2.5 and 4SQ mm cable

The wire strands sizes being 0.20, 0.25 and 0.30 mm dia.

The other high current cables were mainly welding cable which is also small dia strands.

My view is that even house hold coble has too thick strands and solid wiring has no place on a boat or any extension leads that require movement

 

[William_H]

Well OP has been told throw it away. I am of the kind who can't bare to through stuff away. So yeah make up your extension cables for solar. If and when they fail no great loss assuming you can monitor solar charge. Contrary to other 12v DC circuits solar wiring does not need very low resistance wire. Typical 20w panel will generate 1 amp but also has an internal resistance of 20 ohms. Larger panels current is higher and resistance becomes more significant but still not so much. So light wire might drop 1 volt but even that is only 5% loss. The one volt drop taking away from the 20v available and being part of the 6volts dropped in battery charging. In fact for small solar panels robustness of wiring is more important than volt drop. ol'will

 

[Neeves]

Thank you William. I had already decided to ignore the naysayers - as you point out it is a non critical application. I will coil it loosely and a large diameter coil. The Anderson plugs at each end will be stiffened with heat shrink for rope. I can monitor the charge for the roving panel and I can compare the data with a 'dedicated' solar extension that came with the panel - for which I have other uses. I am well aware of the restrictions on use of single core cable on yachts but do wonder if that is still technically valid for all yacht applications - things change. I was actually under the impression that the reason behind the negativity was vibration, constant movement, causing the single core wires to fail (and, for example, if you bundle a single core wire with the rest of a loom the vibration will be minimised).

Time will tell.

I am cognisant of the issues and if it lasts - I'll have saved my inherited cables from going to landfill and saved a bit of copper (and some coppers ) - as I will not need to buy new.

Jonathan

 

[ChromeDome]

Copper can be sold by weight, so might help the cost of buying what you ideally need.

E. g. Scrap Copper Prices | Scrap Metal Sydney

or

Google Oz

 

[Refueler]

If you want yes, Then change your tally to the "Artful bodger"! As others have said not the right cable for the job, might work for a while. You will just have endless trouble with the odd core breaking, difficulty handling etc. Would make me scream if I saw a job like that! I would have to laugh, otherwise would just cry.
That's only my opinion though

Here is a mix of house based cables and multi-strand. I put in the house based over 20yrs ago .. the other was already there ... possibly build in 1973 ...
Not one has failed and need replacement. Even as photo shows with all the work going on to repair that keel in that position - the cables are fine.

I agree that solid core is not advised for cable that is subject to movement ... but it can survive many uses that are fixed. The matter that does come up though with 'house cable' is black wire - especially with 12v DC - where the negative wire turns black ...

 

[Alex_Blackwood]

Here is a mix of house based cables and multi-strand. I put in the house based over 20yrs ago .. the other was already there ... possibly build in 1973 ...
Not one has failed and need replacement. Even as photo shows with all the work going on to repair that keel in that position - the cables are fine.

I agree that solid core is not advised for cable that is subject to movement ... but it can survive many uses that are fixed. The matter that does come up though with 'house cable' is black wire - especially with 12v DC - where the negative wire turns black ...

Agree with what you say. As a professional (Retired) I will stick with my opinion of how a job should be done!

 

[AngusMcDoon]

I'll have saved my inherited cables from going to landfill...

Copper never needs to go to landfill. It's infinitely recyclable and one of the most valuable common metals. Are you not aware of the problem of copper theft because of this?

You asked for an opinion then accused those of us who said that it's inappropriate for your use as negative. I guess you had already made up your mind. The two reasons that will cause solid core cable to fail are flexing & vibration - the former being far more of a problem than the latter. In a static situation on a boat with some vibration but no flexing you'll probably get away with it, but regular flexing as would be the case with a roving solar panel is about the worst use you could put solid core cable to up there with using it to power your lawn mower. But to save a few of your Oz dollars, your choice.

 

[Neeves]

I did not actually ask for advice and asked would single core perform. Conformation was provided in the first few posts.

I have never accepted historic advice without testing it. Its a low risk application. It cost me nothing to try. I'm willing to test it out. If it fails the copper will still be there to recycle.

As far as I can ascertain if it fails as you all predict - then my solar panel will not charge the battery. I have been monitoring the panel/cable/battery now for about 8 weeks, using a power lead specific to solar. I'd like to use the cable elsewhere but want to continue to test the panel/battery.

Don't ask me to quote other traditional advice that has been found wanting.

All I have read is standard mantra, few exceptions.

Watch this space

Jonathan

 

[rogerthebodger]

Jonathan

I have just had a solar panel connector fail at the connection point to the solar panel which was solid ribbon connector.

I had this keeping the battery on my Mobo charges up.

I was away for some time 3 months and the battery self discharged and became flat and could not be recharged.

Cost me a new LA battery which would not needed replacing if the solar panel had not failed

 

[Alex_Blackwood]

"or is my frugality simply showing my ignorance"
Yes!

 

[Refueler]

Jonathan

I have just had a solar panel connector fail at the connection point to the solar panel which was solid ribbon connector.

I had this keeping the battery on my Mobo charges up.

I was away for some time 3 months and the battery self discharged and became flat and could not be recharged.

Cost me a new LA battery which would not needed replacing if the solar panel had not failed

My small 10w panel on my Soviet Mobo - keeps my SLA topped up for the auto bilge pump ... regularly needs the panels wires re-soldered. Its not the lead or plug affair ... its the actual copper solid wire that connects the panel terminals to the connection point. Panel doesn't move ... its relatively free of vibes from the motor as its mounted via industrial thick velcro. Mystery !!

 

[rogerthebodger]

My small 10w panel on my Soviet Mobo - keeps my SLA topped up for the auto bilge pump ... regularly needs the panels wires re-soldered. Its not the lead or plug affair ... its the actual copper solid wire that connects the panel terminals to the connection point. Panel doesn't move ... its relatively free of vibes from the motor as its mounted via industrial thick velcro. Mystery !!

Agree but its a matter of knowing when the connection has failed.

I live 800Kn away from by boat so cannot just pop down to the bottom of my garden to check the battery state