Is Wire Length Important? (1 Viewer)

[Yorick]

I've just bought a folding 100w panel but the lead is only 2.5 metres long. It barely reaches the battery from left side, but no chance from right side.

I think I read somewhere that if the lead is too long, then it loses volts/amps or whatever

Put me out of my misery please

 

[pappajohn]

Correct.....volt drop over a long distance.

Just extend the leads using 4mm to 6mm flexible cable.

 

[Yorick]

Correct.....volt drop over a long distance.

Just extend the leads using 4mm to 6mm flexible cable.

Sorry, that's a bit ambigous to me....

The wire it comes with is 4mm (if you measure the outside). So should I extend it with 6mm ?

^{_{Subscribers  do not see these advertisements}}

 

[LaMB]

I bought some of this for my solar wiring:-

Broken Link Removed

It should be fine for you. I hope the link is correct.

Martin

 

[pappajohn]

Sorry, that's a bit ambigous to me....

The wire it comes with is 4mm (if you measure the outside). So should I extend it with 6mm ?

If it comes with 4mm then use the same.

Volt drop only really becomes a real issue if the cable run is very long....batteries at front of van and contoller at the back.

 

[pappajohn]

Just realised you dont mention a charge controller........100watt panel will cook your battery without one.
the controller fits between battery and panel and regulates the charge current to prevent overcharging and boiling.

DONT connect directly to your battery.

^{_{Subscribers  do not see these advertisements}}

 

[Wildman]

I bought some of this for my solar wiring:-

Broken Link Removed

It should be fine for you. I hope the link is correct.

Martin

well actually no it is not big enough dia to prevent voltage drop

• Conductor Area CSA:2.12mm²

Is not 4mm² which is what you need.

 

[LaMB]

well actually no it is not big enough dia to prevent voltage drop

• Conductor Area CSA:2.12mm²

Is not 4mm² which is what you need.

I don't think the voltage drop on a couple of metres would be significant though for the OP to worry about, and I rather think the OP has measured the cable diameter including the insulation.

 

[Minxy]

I've just bought a folding 100w panel but the lead is only 2.5 metres long. It barely reaches the battery from left side, but no chance from right side.

I think I read somewhere that if the lead is too long, then it loses volts/amps or whatever

Put me out of my misery please

Maybe I'm missing something but ... it's a folding PORTABLE panel ... so move it nearer to where the battery is!

^{_{Subscribers  do not see these advertisements}}

 

[LaMB]

Maybe I'm missing something but ... it's a folding PORTABLE panel ... so move it nearer to where the battery is!

Yes I think you are. If the OP moves it nearer the battery it may then be in the shade!

 

[Wildman]

I don't think the voltage drop on a couple of metres would be significant though for the OP to worry about, and I rather think the OP has measured the cable diameter including the insulation.

for safeties sake all solar cables should be at least 4mm² but please yourselves. When light levels are low ANY loss is unacceptable if it can be avoided

 

[LaMB]

for safeties sake all solar cables should be at least 4mm² but please yourselves.

?

^{_{Subscribers  do not see these advertisements}}

 

[Wildman]

losses are in the form of heat, too small a cable and there is potential for a fire, especially on a cable exposed to the sun and already heating it up. Better safe than sorry.

 

[LaMB]

losses are in the form of heat, too small a cable and there is potential for a fire, especially on a cable exposed to the sun and already heating it up. Better safe than sorry.

100W at 12v = less than 9amps so 20 amp cable would be overkill anyway!

 

[pappajohn]

The cable the panel comes with is just adequate.

8amps at 12v with a 3% volt drop over 2.5mtrs = 2.5mmsq cable

Same parameters over 4mtrs = 4mmsq

Same parameters over 5mtrs = 6mmsq

Same parameters over 10mtrs =16mmsq

^{_{Subscribers  do not see these advertisements}}

 

[tonka]

LOL.... What a fuss.. Here is the Funster answer..

Yea shove some cable on and get on with it..
It will still work ......

SORTED.........

 

[Yorick]

Just realised you dont mention a charge controller........100watt panel will cook your battery without one.
the controller fits between battery and panel and regulates the charge current to prevent overcharging and boiling.

DONT connect directly to your battery.

Yes, it comes with a controller

 

[Yorick]

I don't think the voltage drop on a couple of metres would be significant though for the OP to worry about, and I rather think the OP has measured the cable diameter including the insulation.

yes, it is 4mm diameter. Is that big enough for a 4m long cable ?

^{_{Subscribers  do not see these advertisements}}

 

[Yorick]

Maybe I'm missing something but ... it's a folding PORTABLE panel ... so move it nearer to where the battery is!

I can't coz the cable is too short

Only 2.5m and leisure batteries are inside the van and half the cable is in the van

 

[DavidG58]

yes, it is 4mm diameter. Is that big enough for a 4m long cable ?

I spent ages thinking size meant diameter, it refers to cross sectional area, so actually quite small dia which will include the outer cover

 

[hilldweller]

so actually quite small dia which will NOT include the outer cover

You've missed a NOT out.

^{_{Subscribers  do not see these advertisements}}

 

[DavidG58]

You've missed a NOT out.

Technically I did not miss the NOT on the basis that I think Yorick was quoting OD of his cable which would have included the cover

you are of course quite correct that you shouldn't include the cover in the calculation of core dia

 

[Yorick]

I spent ages thinking size meant diameter, it refers to cross sectional area, so actually quite small dia which will include the outer cover

4mm overall dia will be about 3mm wire dia which is 7mm2

Is this enough ?

 

[DavidG58]

4mm overall dia will be about 3mm wire dia which is 7mm2

Is this enough ?

I can only concur with your maths

no idea about elec specs, but it sounds good to me

^{_{Subscribers  do not see these advertisements}}

 

[Yorick]

I didn't get chance to sort it before I came away, but have found a perfect solution.

ta da

 

[Frentchy]

I didn't get chance to sort it before I came away, but have found a perfect solution.

ta da View attachment 72592

Does it work through glass my auto sun glasses don't

 

[Yorick]

Does it work through glass my auto sun glasses don't

Yup

^{_{Subscribers  do not see these advertisements}}