Thread: solar panels

15m is a long way,expect a big current drop.See what the ellecy teccys say about size.
I would regulate it at the vehicle,if you are going to loose current best to loose it before you regulate it.
Best to use anderson plugs to make the connections.
Andrew

Originally Posted by scoota

Ive just bought a 120w folding solar panel to run off a deep cycle battery when camping, and I've got some questions:
1. I want to run 15metres of cable from the panel to the 4wd mine is at least 10m long and i don't have voltage drop issues - is it ok to plug the panel into a 12v accessory plug (cig lighter) rather than direct to battery? i agree with andy, best to use an anderson plug set that foes direct to the battery
2. Would 6mm cable twin sheath (distance over 15m) be thick enough? bigger the better, a solar shop size the cable for me...sorry i have no idea what size it is
3. Is it ok to have the regulator attached direct to the panel or is it better positioned in the 4wd. yes on the solar panel is the best place
Cheers, Scoota

120W is a nice size

The instructions with my voltage regulator suggest putting it no more than 1m from the battery, to allow for voltage loss on your cable run.

Your 120W panel will generate about 8 amps at peak conditions, although on average it's going to be way less. It's always best to keep the cable as short and as thick as possible to minimise the voltage drop. However it's always a compromise, and 6mm cable should be a good trade off between size and convenience.
I agree the regulator should go near the battery. It's whatever voltage is presented at the battery end, after any losses in the cable, that needs to be regulated.

Oh, and cigarette lighter sockets were designed for lighting cigarettes, any other use is a compromise....don't plug into that, go direct to the battery, easiest way is with a short fly lead off the battery to an in line plug & socket --- yes Anderson or similar.

the cable i use is the 100 amp jumper cables from super cheap 2.5 m long $ 13.90 just take the clips off

dont forget your fuses.

I'll add my basics here..

if you regulate at the battery then you have higher voltage in the cable (less current) which i beleive means less loss along the cable (hence the reason that power lines are high voltage low (relatively) current)

however in my case... i'll be regulating on the panels as i will be using them both on the car and the boat. so just need flying leads to plug into. There are websites that will work out voltage loss along a length of cable....

Im probably wrong, but at least i know it

Thanks

Steve

10 amp regulators are cheap enough, why not put one in the boat and one in the car OR...

put a regulator and plug on the panel alongside an unregulated plug that you can plug the vehicle mounted regulator into?