Wiring solar panels into a D3’s traxide system

[Ooops]

Hi all,


I’m looking to add some permanently mounted solar panels to the roof rack on my D3.
The car has an SC80-12 based Traxide system fitted.


I’ve read that its not ideal for the solar reg to be in the heat & exposure of the engine bay, that the wiring run from reg to battery should ideally be as short as possible and that
its ok for power from stand alone panels to be introduced to the system via the rear Anderson.


I was thinking of bringing the cables into the vehicle in the tailgate area using the same techniques employed for aerial cabling and feeding them into the rear AC compartment.
where they’d to join up to the Aux battery side of the ABG-25.


I believe that with the SC80-12 this will only keep the aux battery topped but balanced this against the location being a convenient and protected spot for the solar reg.


So my question is can will this work or is it essential / best practice to go down the A pillar, fit the reg in the engine bay and connect to the crank battery?


TIA

[drivesafe]

Hi TIA, the reason a solar regulator should be located close to the battery it is charging, is because when placed some distance from the battery, with thin cable, there will be a voltage drop.


This voltage drop can be enough to make the solar regulator “THINK” the battery is fully charged when it is not.


But because of the thickness of the cable running ( in this situation ) from the rear cargo area to the auxiliary battery, there will be very little noticeable voltage drop between the solar regulator and the auxiliary battery.


So your charging will be fine.


Also note, if the two batteries have not been discharged below 12.0v when the solar starts to supply power to the batteries, then the SC80 will still be on and the two batteries will be continually charged while the sun is up.

[Ooops]

Hi TIA, the reason a solar regulator should be located close to the battery it is charging, is because when placed some distance from the battery, with thin cable, there will be a voltage drop.

This voltage drop can be enough to make the solar regulator “THINK” the battery is fully charged when it is not.

But because of the thickness of the cable running ( in this situation ) from the rear cargo area to the auxiliary battery, there will be very little noticeable voltage drop between the solar regulator and the auxiliary battery.

So your charging will be fine.

Also note, if the two batteries have not been discharged below 12.0v when the solar starts to supply power to the batteries, then the SC80 will still be on and the two batteries will be continually charged while the sun is up.

Thank you Tim that's brilliant info. I have a couple more questions if I may.

Can I introduce the cable from the regulator at any point along the pathway of the 6B&S/13.5mm2 cable?
Should I run an inline 30 Amp blade fuse where the regulator cable joins the 6B&S/13.5mm2 cable?
I picked 30 amp to match that of the supply to the ABG-25

Should I run individual panel fuses of a value that matches the max output of each of the panels and another of the combined value where the solar panel cable joins the regulator?

And slightly off topic, with a plug sticking out of the existing power sockets I find it to be a bit vulnerable to knocks, vibration & dogs, so I was thinking about adding an additional take off with an Anderson plug fitted to run the fridge from. Should I connect this to the output side of the ABG-25 as per two normally fitted power sockets or can I tap into the 6B&S/13.5mm2 cable any where and fit an in line fuse sized to match the fridge?

Thanks

Olly

[Ooops]

Oops - from notes I'd made earlier

Fuse the panels at Amps max
Fuse as near to the panel as possible
Fuse the regulator at the regulator

main

• 6 B&S Gauge = 7mm Dia
• 7mm Dia = 13.56 mm2 Area
• 192/0.3 Strand Nos/Size

fridge spur & panel wiring

• 11 B&S Gauge = 4.59 mm² dia
• 4.59 mm² Dia = 6mm auto cable
• 65/0.3 Strand Nos/Size

[Strop]

Just a thought based on some of my reading and a talk on solar power I went to.

Putting the solar panel on the roof as a permanent mount brings with it issues. Main one is that you can't really park in the shade. The efficiency of mono-crystalline panels, which are cheaper because of the number produced, reduces dramatically when in the shade or when they have any shade over them. Does not have to be a lot of shade.

There are panels that work better in the shade - Amorphous panels. They are more expensive and I believe there are issues or problems you need to consider be they 12/24/36 volt. This will impact on the controller you need. I am sure Tim will be able to expand on this. But I don't believe you can put 24 or 36 volts into a 12 v system. Can't remember if this issue comes with some mono-crystalline panels. Anyway beyond my expertise level.

I am considering buying an amorphous blanket (100 W) to use with my tourer when setup. I use folding 180W panel with my camper trailer. It is in the shade and the panel is in the sun but I have room to store the panel.

The blankets can be folded up and stored in little space as opposed to a 100W fixed or folding panel. It is a significant price difference though. I was then hoping to plug it into the Anderson Plug at the back as Tim has said you can. Throw it on roof or bonnet or place out on the ground. That way the car can be in the shade and panel in sunlight. With the tracked kit the panel is really redundant when driving as the alternator should do all the work.

[Ooops]

Thanks for that Strop, however in my case that's not an issue because when it comes to natural shade there simply isn't any.
You're in direct sunlight whether you like it or not and the only thing to be done is to cover the windows etc. So in this case its actually works for me.

[Strop]

Wasn't expecting that answer.

In that case the more the merrier. Create a sun barrier so it doesn't beat down on the roof. Keep the car and the fridge cool.

All the best

Laurie

[Ooops]

Wasn't expecting that answer.

In that case the more the merrier. Create a sun barrier so it doesn't beat down on the roof. Keep the car and the fridge cool.

All the best

Laurie

I know, nobody likes a smarty pants
That’s pretty much it, you have to envelope the vehicle in shade to stop it melting

[DiscoMick]

I haven't found any problem with having the panel on the roof. The panel and roof rack shade the roof a bit. Put a sunshade on the windscreen and open a window to let hot air out and help the fridge.
I still think it's better to charge the starting battery first. However charging the second battery first should be OK as long as the start battery does not drop low enough to cause the Traxide to separate the batteries.

[Ooops]

I still think it's better to charge the starting battery first

I agree DM and it would have been my first choice but I didn't want the controller in the engine bay