Page 1 of 1

Solar panel what to buy

PostPosted: Mon, 05 Aug 2019 8:32 +0000
by jabiru18
Hi,

I have a dual battery setup with redarc 1225D (Solar input) and want to have solar charge the battery, what panel should I buy? What wattage is suitable?

Looking for something robust as 80% of my driving is dirt/Corrugation.

I also have a trailer with a Battery I would like to charge via solar and maybe from Alternator. Can I add a third battery to the Redarc or whats the best way to go to keep that battery charged?

Re: Solar panel what to buy

PostPosted: Mon, 05 Aug 2019 9:28 +0000
by HK1837
I bought a Kings 110W and mounted it between the roof racks on the canopy. If setup right with a quality MPPT solar regulator like a Victron it keeps the battery happy. I use a 105Ah Century deep cycle.

Here is the panel, cheap and a good shape:
https://www.4wdsupacentre.com.au/110w-f ... gInFvD_BwE

Make sure whatever regulator you use it has a dedicated load output for cyclic loads like fridges, so that the battery and fridge are not paralleled all the time.

Re: Solar panel what to buy

PostPosted: Mon, 05 Aug 2019 7:18 +0000
by jabiru18
Thanks man. That looks perfect. Great price. I’ll grab one for Ute and trailer.

Re: Solar panel what to buy

PostPosted: Tue, 06 Aug 2019 5:15 +0000
by HK1837
I figured they were cheap and if it lasted 5 years i’m happy. Been going good now for over 2. I stuck an Anderson plug on the leads. In the middle of summer I have seen 100W out of it and in winter about 45W with it dead flat across the racks. If you tilt it you’ll get better output.

Re: Solar panel what to buy

PostPosted: Tue, 06 Aug 2019 9:46 +0000
by jabiru18
For sure, for that price a few years is good economics.. Looks like you are getting a good output too.

Are there any mounts which can give a bit of angle. I see the ones at SupaCentre are flat, which is fine but I can seem to find brackets where i can permanent mount at 10 or more Degrees. I would be happy with a slight tilt, maybe I could put a spacer in the rear mounts..

Re: Solar panel what to buy

PostPosted: Wed, 07 Aug 2019 9:32 +0000
by HK1837
I’m not sure it is worth tilting it on a vehicle as the vehicle can be oriented in any different direction. Plus with power output vs sun tracking you are actually better off following the sun across the day rather than tracking it across the seasons, at least in Sydney latitude. This is for a fixed install on a building or the ground though, whereas on a vehicle you never know where and how you can park. I just looked at mine 10min ago, parked on an across slope with the down slope towards the south so the panel is tilted away from the sun. It was putting out 58W at just after 11am on 7th August in Newcastle. That is about 4.0A out of the regulator at 13.8V. Unless it was titled so the panel was far closer to 90deg to the sun you wouldn’t get much more than that out of it, a few degrees of tilt would only be marginal gain, and then other times you’d tilt away from the sun if parked differently.
I’ll try and get some photos how I mounted mine.

Re: Solar panel what to buy

PostPosted: Wed, 07 Aug 2019 3:37 +0000
by grunf
HK1837 wrote:
Make sure whatever regulator you use it has a dedicated load output for cyclic loads like fridges, so that the battery and fridge are not paralleled all the time.


Hey mate can you elaborate more about this please?

Re: Solar panel what to buy

PostPosted: Wed, 07 Aug 2019 5:14 +0000
by HK1837
grunf wrote:
HK1837 wrote:
Make sure whatever regulator you use it has a dedicated load output for cyclic loads like fridges, so that the battery and fridge are not paralleled all the time.


Hey mate can you elaborate more about this please?


The better solar regulators have LOAD and BATTERY terminals so that the load and battery aren’t always paralleled. The reason is that the battery charging part of the regulator charges and conditions the battery by what it sees the battery taking in terms of current, like any good charger does. If you have a cyclic load like a fridge straight off the battery it can confuse the charger. So by separating the load from the battery the regulator gets to do its job better, plus it can turn off the load when the battery discharges to a certain level. Big loads like winches, high wattage inverter etc go straight off the battery but small cyclic stuff like fridges best to let the solar regulator look after them. Plus when you are charging batteries that take a higher charge voltage you let the regulator provide that but also provide 12V to the fridge as the loads are separated.

Re: Solar panel what to buy

PostPosted: Wed, 07 Aug 2019 6:52 +0000
by ggreenie
grunf wrote:
HK1837 wrote:
Make sure whatever regulator you use it has a dedicated load output for cyclic loads like fridges, so that the battery and fridge are not paralleled all the time.


Hey mate can you elaborate more about this please?

Just use your redarc unit like you planned mate. Plug the unregulated solar panel straight into that. It has its own high quality solar regulator.

Re: Solar panel what to buy

PostPosted: Mon, 12 Aug 2019 2:32 +0000
by jabiru18
HK1837 wrote:I’m not sure it is worth tilting it on a vehicle as the vehicle can be oriented in any different direction. Plus with power output vs sun tracking you are actually better off following the sun across the day rather than tracking it across the seasons, at least in Sydney latitude. This is for a fixed install on a building or the ground though, whereas on a vehicle you never know where and how you can park. I just looked at mine 10min ago, parked on an across slope with the down slope towards the south so the panel is tilted away from the sun. It was putting out 58W at just after 11am on 7th August in Newcastle. That is about 4.0A out of the regulator at 13.8V. Unless it was titled so the panel was far closer to 90deg to the sun you wouldn’t get much more than that out of it, a few degrees of tilt would only be marginal gain, and then other times you’d tilt away from the sun if parked differently.
I’ll try and get some photos how I mounted mine.


I am with you there, Ill just mount flat, my Ute is a bit higher at the back and actually gives a bit of an angle.
ggreenie wrote:
grunf wrote:
HK1837 wrote:
Just use your redarc unit like you planned mate. Plug the unregulated solar panel straight into that. It has its own high quality solar regulator.


Yep, thanks for that. Thats one thing I like about the panel HK posted, no regulator so not paying for something to take off.

Hoping to install this coming weekend.

In regards to the trailer, is solar enough to keep the battery charged? Will only be running LED lights. Then I can have trailer completely separate from Vehicle wiring?

Re: Solar panel what to buy

PostPosted: Mon, 12 Aug 2019 8:42 +0000
by fracturedranga
I've got a 275W house panel for my camper trailer it's huge and annoying to drag around but it was half the price of a camping one for more wattage and keeps my battery happy