Solar Panels - Information and Questions

[ProspectorPete]

Usually the 80w panel in full sun keeps my battery at 13.7v while the fridge is on and it's never let me down but right from the start of this trip it wasn't throwing any charge in, the deep cycle was down to 12.4v after 3 days which is no issue as I connect it via an anderson plug at the rear of my 4x4 and it charges while travelling, I tried the panel on my 4x4 and same deal not charging so definitely an issue at the controller.
I've never really needed more that the 80W panel, I know people say 120W or 160W minimum but my 80W seems to be sufficient for my needs, if it needs a new controller then I may invest in a new 160W panel for camping and split the 80 into 2 x 40W panels as permanent top-up systems on my boat and camper while at home.

 

[ProspectorPete]

Exactly Doug, normally it does.

 

[Simmo]

Hey mate,
What I found with my 150 folding one is that the regulator being stuck to the back of the panel, gets bloody hot and doesnt last. Just get a cheap MPPT regulator off ebay mate, that'll fix it.

 

[Reeks]

Hey mate,
What I found with my 150 folding one is that the regulator being stuck to the back of the panel, gets bloody hot and doesnt last. Just get a cheap MPPT regulator off ebay mate, that'll fix it.

There is vids of these "cheap" MPPT controllers on youtube where they are nothing more than a PWM with MPPT sticker/writing

These guys are Australian were very helpful on the phone and make real MPPT regulators for a realistic price
http://www.gsl.com.au/mppt12p.html

I myself use a redarc 72w amorphous fold up panel with a redarc PWM reg.
bigger camp set ups would benifit from MPPT charging.

In short, stay clear of china ebay regulators :Y:

 

[user 7268]

As Reeks has said ...................... plus most of the controllers supplied with the panels at purchase are just rubbish :N:

 

[7.62marksman]

This is my setup
I started with a 80amph battery being charged of a 120w solar panel but the fridge kept flatting the battery over night set on 3
I have now got a 120w solor panel off auto barn it has a built in regulator and is mounted on the roof of my 4x4 (the xl body not veh roof) this is then connected direct to the secondary battery 120amph
On a sunny day and with my waco fridge set at 3 going 24 7 it does not go under 13v during the day but over night will drop to about 10.5
All lights tv ect ect are connected to the secondary battery leaving my main start battery just for that only
Along with this i have it connected direct to the alternator through a iserlator switch so if i am driving at night it will charge that way as well
I have had this setup for 2 years and at this stage i have had no problems at all everything is covered by fuses
I know some will say it should not be set up this way but it works and that is the main thing

 

[Occasional_panner]

Jeeeeeeeeeezzzz, you draw the battery down to 10.5?
Crikey I thought going down to 12.0 was bad.

 

[7.62marksman]

Yes but i have found it dosent go any lower if i just run the fridge at 3
the last few days of heat it never went under 12

 

[ProspectorPete]

Wow 7.62, I think that fridge is either pulling to much or the battery is on the way out.

I run my Engel on 3 deg 24/7 and after 3 days with no solar I'd be surprised if my battery was below 12v, that's why I get by with the 80 watt panel, keeps the batt at 13.7v during the day and 12.6v by morning after I've been in/out the fridge 6-8 times after dark for refreshments.
On my last trip when the solar panel didn't work my campers AMG battery was at 12.4v after 2 full days with the fridge in full sun at 32 deg.

Reeks, thanks for that and I'll def follow up on that link, I'd be happy to fix this panel up with a GC product :Y:

 

[Occasional_panner]

Pete yeah sounds like the controller is knackered.
AND you only go to the fridge 6-8 times, mate I must have a problem I'd do that by 6pm

 

[ProspectorPete]

Haha Op, my 6-8 visits are after dark only, hadn't mentioned how many day light visits there are

Just placed an order for a new GSL PWM SR1212-2 controller/regulator, thanks all for the replies and help with this one.

 

[condor22]

This is my setup
I started with a 80amph battery being charged of a 120w solar panel but the fridge kept flatting the battery over night set on 3
I have now got a 120w solor panel off auto barn it has a built in regulator and is mounted on the roof of my 4x4 (the xl body not veh roof) this is then connected direct to the secondary battery 120amph
On a sunny day and with my waco fridge set at 3 going 24 7 it does not go under 13v during the day but over night will drop to about 10.5
All lights tv ect ect are connected to the secondary battery leaving my main start battery just for that only
Along with this i have it connected direct to the alternator through a iserlator switch so if i am driving at night it will charge that way as well
I have had this setup for 2 years and at this stage i have had no problems at all everything is covered by fuses
I know some will say it should not be set up this way but it works and that is the main thing

10.5 volts is dead flat voltage, I'm surprised your low volt Waeco cut out doesn't stop before then. I run my Engel all night from a 100AH and it still shows 12.3V in the morning. (winter time when it's cold and batteries do suffer near freezing temps)

So either the battery aint getting charged properly each day and has a cumulative discharge over several days, or it aint holding charge, in which case it's on it's way to battery heaven.........

 

[7.62marksman]

thanks guys i will put it in for a test
the fridge is 2 years old BUT always a but it has had a hard life so maybe its on its way out as well

 

[Occasional_panner]

7.62, you could get one of these http://www.ebay.com.au/itm/150-AMP-...256886?hash=item282af2f336:g:pcAAAOSwA3dYmWsf
Or just use a multimeter, most will allow short currents of 10A. I would be worried if you were pulling 5 or more, if the fridge is only 2yo I'd be pointing the finger at the batterry, like condor said it's either knackered or not getting charged properly.
maybe pop into an auto elec and get them to do a load test on the battery.

 

[7.62marksman]

Thanks OP will do that tomorrow

 

[condor22]

As I've said on other posts

Drawing between 25-50% of battery capacity will give you 6-10 years from a good AGM (I/e 25-50AH from a 100AH.

Regularly pull it down below 50% or a few times to flat, you'll be lucky to get 2 years.

 

[ProspectorPete]

Hi guys, just an update on the original post.

I ended up buying a GSL SR1212-2 regulator but have a question regarding the BLUE chemistry wire, on the photo you'll see it says Floating for AGM/GEL batteries, the deep cycle battery in my Camper trailer is AGM and the deep cycle on my Landcruiser is acid (Flooded?).
I'm happy to wire the regulator up for the camper trailer so a couple of questions.

1. I assume the 'FLOATING' means not connecting the blue wire?
2. If that's the case what repercussions would there be hooking up the solar panel to my ute when I'm out bush without the camper trailer?

I'm heading out to the GT for 7-8 days detecting in at the end of this month and undecided if I'll take the camper trailer or just swag it depending if I stay in the one spot or decide to go between 2-3 locations (still to be decided). Either way I'll be taking the solar panel as I'll probably run my Engel as fridge/freezer for the trip.

Cheers guys.

 

[condor22]

Pete,

Yes "floating" means don't connect it to anything, insulate it to prevent it contacting anything.

The ramifications are this;

An AGM usually charges at 14.5V in Absorption mode whereas a wet cell is lower at about 13.8V. Smart chargers monitor battery state to decide how to best charge it. Each battery type has a charging algorithm suited to it, using a different charging mode can basically do 2 things 1. not charge properly and 2. reduce the life of the battery.

Give me 5 minutes I'll do up a diagram to show how you can use the regulator for both with a simple switch arrangement.

 

[condor22]

Pete here is the circuit the first shows the switch open for the AGM, the second for the wet cell.

AGM

WET CELL

Go to Jaycar, get a SPST (single pole, single throw) or simply an on/off switch. Rocker or Toggle and able to handle 20V and 12 amps. I say 20V as it connects to the raw input of the panel.

You could buy a small plastic "jiffy box" to mount the switch and tidy up the wires as well as insulate from any shorting. The regulator will be close to the battery, so place the switch nearby. The longer lead will be between panel and regulator.

 

[ProspectorPete]

Thanks Condor22, looks easy enough to do.

I've just gone out and got the details of the batteries I'm running and they are as follows:

Landcruiser HZJ79 Duel battery setup. Not sure of the system used if it's factory or not as there's too much stuff under the bonnet to find it.

Crank Batt = Yuasa SMF Series, CCA 760, RC 165
Aux = Amp-Tech D70Z deep cycle, 105ah, says that max charge is 14.4v so I'm thinking I would be ok to use the same setup on the regulator as with the AGM?
I have 6mm lead running from the Deep Cycle to the rear of the ute (fused) connecting to Anderson plug to connect and charge camper trailer while driving, I also connect the solar panel for the ute from this plug.

Camper Trailer running Anderson plug to battery (fused) then battery to fuse box and 2 x 12v sockets (cig lighter) for running accessories like fridge.

Battery = Antenergy AGM 105ah 840CCA

Not sure if I'll need to put a switch in for the 2 different deep cycle batteries?