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threedogs
15th March 2013, 12:09 PM
Found these panels on Ebay Folding 100 watt for $139. BUT
they only put back around 2.3 amps.
I would have thought more like 6 amps
I've sent a message hoping its a typo, as my 80 watt panel returns 4.5 amps
Unless they are 24 volt jobs I'll see what they say
Seller is aus-auc

wildgu6
15th March 2013, 12:34 PM
Depends if Chinese or German, German are the better product


TAPPN OUT

threedogs
15th March 2013, 12:55 PM
Just has a very low return, found another 95 watt panel that returns just on 7 amps for $150. but not folding.
1200x560x35
Sounds like their stats are for 50 watt panel only, nothing wrong with my 80 watt BP panel,
just want to retire it for backyard duties, bought over 15 years ago for $150, they are ex telecom panels that get changed every 3 yrs I think
never failed be yet and still 100% efficient..IMO dont need a lot of panels as with sensible accessories just the Aux battery in Patrol For Engel {Food only}
and awning led. Another 105 AH battery in camper for UHF radio[Base camp} cd player and all camp lighting, then a smaller 18 ah battery in a battery box for remote lighting duties, eg Lights on river bank for night fishing. NEVER EVER ran out of battery. Even better if travelling every day, Dont over complicate your camp needs with un wanted batteries {Heavy} or panels,

Cuppa
15th March 2013, 01:16 PM
The first one ou put up has a 'house' voltage. Could be used with the right regulator, but if the supplied regulator went bung you it would not be quite as straightforward to replace (& the supplied regs & cables are best replaced anyway). I wouldn't,t buy that one myself.
The second one, 'just on 7 amps' for a 95watter sounds a tad suss.

For cheapness & a folding panel too I'd have a look at this one (http://www.ebay.com.au/itm/NEW-GP-100w-Folding-Portable-Solar-Panel-Kit-Home-Battery-Camping-Caravan-Power-/160962726374?pt=AU_Solar&hash=item257a2049e6&_uhb=1#ht_3156wt_1382)

Or for a known quantity (& quality), from a reputable seller, & a folding 120w panel this one (http://www.ebay.com.au/itm/120W-FOLDING-SOLAR-PANEL-MONOCRYSTALLINE-COMPLETE-SET-/360466559807?pt=AU_Solar&hash=item53ed7b333f#ht_2202wt_979)

Cuppa

oncedisturbed
15th March 2013, 01:53 PM
Had a look at the links Cuppa, the 100w set has just peaked my interest


Never underestimate the power of the Tap.

threedogs
15th March 2013, 03:48 PM
Around 5 ah is plenty for my camping needs. wouldn't need it going to cape york as travelling everyday.
my ice box exceeds my ice retention needs. so fuel every day travelling even every 2nd day, buy fuel, buy ice.
just trying to sort stuff out for big trip soon.

oncedisturbed
16th March 2013, 10:50 AM
I ended up purchasing the 100w set that Cuppa posted, just have to wait for them to come in now

Cuppa
16th March 2013, 12:39 PM
I ended up purchasing the 100w set that Cuppa posted, just have to wait for them to come in now

Gee, I hope they'll be ok!
Check'em out with a multimeter when you get them & let us know. Don't forget that to get what you hope for into your batteries you need to replace the weedy supplied cables with something beefier (longer the leads the thicker you need). Also worth looking at a better regulator, but if you go with the supplied one see if you can remove it fom the rear of the panel & relocate it to the vehicle, closer to the battery it's charging.

Cuppa

oncedisturbed
16th March 2013, 06:24 PM
am only running an 80hr hybrid battery at the moment with a 50L Ironman fridge. Mainly wanted them for "top-ups" when stationary.

Will go through it properly when I get and may look at replacing the charge controller if needed. I have 2 rolls of 50A twin core cable and a heap of 50A Anderson plugs at home so making up new leads won't be an issue.

Average power usage on the fridge is 40 watts and AH/H is 0.7A based on internal 5c and outside of 20c, this will change of course depending on what is being done and settings etc

Woof
16th March 2013, 06:35 PM
Will be waiting to hear your report Oh Disturbed One

threedogs
16th March 2013, 06:43 PM
Remember you can go too big in wire size, what you intend using sounds fine,
Anderson plugs worth their weight in gold love them
You wouldnt use welding cable to run an indicator would you, or would you.

oncedisturbed
16th March 2013, 06:45 PM
will confirm the size when it comes in as it may be the 50A is to big and may have to drop slightly

threedogs
16th March 2013, 06:50 PM
Other than powering a winch I think 6mm cable is heaps for most H/D automotive jobs
Amps and Hi tech radio equipement excluded doof doof

Woof
16th March 2013, 07:33 PM
I need one just to keep my 60 litre Engel fridge/freezer running, so my question is would this one do it without any changes..........I know nothing about solary/eletricy stuff

Cuppa
16th March 2013, 08:27 PM
Re.the discussion on cable size for solar

To make sense we need to refer to the mm2 of copper in the cable rather than the amps it can carry, as the size of cable to amp carrying capacity ratio varies with voltage.

6mm autocable may be sufficient for most things automotive, but often only has about 4.5mm2 copper (the thickness of the insulation being included in the measurement of autocable). 6mm autocable is insufficient for most but the smallest solar installations.

6mm2 cable would be be the minimum for a single 100w panel & 10m of cable.

You can't go too big in cable sizing from a solar point of view but of course the compromise needed is to avoid excessive weight. Also the bigger you go the more the returns diminish. There are plenty of web sites which will tell you what size cable you need for a given voltage drop. Aiming for a max voltage drop of 3% is reasonable for solar installations. For 300w of portable solar & 9 metres of extension cable I use 6 b& s cable which has 13.3mm2 of copper, which is getting close to light welding cable. To go to say 12 metres I would use 16mm2 which is light welding cable!

The following link has a good table for determing solar cable sizes
http://hobohome.com/news/?p=581

Cuppa

Cuppa
19th March 2013, 03:33 PM
Another link.
http://stores.ebay.com.au/Low-Energy-Developments?_rdc=1
This mob come very well recommended within the Motorhome & Caravan community.

Cuppa

3kids
24th March 2013, 07:06 PM
Hi all,
I am presently setting up a camper trailer and as luck would have it I am an electrician (heavy industrial). After a heap of private research I have just put a rev 1 system together.
Firstly let me state that all prices I got from an auto spark literally tripled the cost of what I believe you need (lots of smoke and mirrors).
A 50 amp anderson plug can only just accomodate 6 B&S (13.5mm2) cable with some strands not being able to fit in the lug. 8 B&S (6mm2) fits comfortably.
As stated all cable lengths need to be below 10 metres due to voltage drop (when starting from a low base like 12 volts VD becomes a show stopper for recharging) and cable size is minimum 6mm2
The MPPT charger that is supplied with a quality solar panel is OK (but) they usually do not come with a cut out to prevent overcharging and can damage/reduce battery effectiveness. To really extract the most out of a system and keep it simple is to have a DC-DC charger that can simultaneously charge with the alternator and solar or individually. These units provide optimum charge rates (incoming voltages of say 11.5 volts are converted to 14.6 volts) and cut out to prevent over charging. You can also connect and leave connected a 240 volt charger eliminating change over of leads when you park up after the trip or hit the powered site. Ensure the charge unit or regulator is paced as close as is possible to the batteries.
Please feel free to ask questions as I am in the process of building this and so far the results have been above expectations. > 6 days and nights with 2 x 100w solar panels and the batteries never dropped below 80% running LED's and engel, by the time we returned to Perth the batteries were back to 100% via the alternator.

Cuppa
24th March 2013, 07:37 PM
Which Dc to Dc charger have you fitted Dave? The Redarc BCDC1240 I have handles solar or alternator, but not both at the same time. Precedence is automatically given to the alternator. I too am similarly impressed with how well these things work.

Cuppa

3kids
24th March 2013, 08:18 PM
Hi Cuppa,
At present I am experimenting with the CTek DC-DC charger with a Smartpass unit parralled with it (sampling them from 1 of our contractors on site). The unit is mounted nearly on top of the batteries being charged. Alternator feed is via a 50 Amp anderson plug wired with 6B&S cable (13.5mm2). Yes some of the flexible copper strands are not captured by the lug but I took great care to ensure no short circuits. Voltage at the rear of the tow vehicle (not a patrol) is 15.5 volts. Due to trade access I have used 6mm2 twin as a minimum for any back bone cabling with 2.5mm2 cable breaking out in short runs to LED's which aren't affected too much by VD. All joints and terminals are crimped or soldered and the main form of connectors are anderson plugs for the trailer to tug and power poles for all else (these just accommodate 6mm2 cable). The power poles are brilliant for slightly smaller cable sizes and can be used over and over without compromising the quality of the joint or being too bulky.
1 point I am researching is that new alternators (2010/2011 onwards for all makes and models) are not capable of delivering a voltage of consistency to work like this due to electronics. I will be searching for a solution (and or confirm this is the case) to this as my new toy as of tomorrow is a 2012 Patrol (cant wait).
The two panels are cheapies but after using a tong clamp I am reading 7.9 amps in the morning prior to driving off for the first time. At camp I was only recieving full sun from 10 AM onwards. The main thing to have for me is the cut out for protection of the batteries and if using a regulator/controller it is of the MPPT variety C/w cut out. All the regulators/controllers I have viewed to date dont seem robust enough and I have my doubts.
The other advantage of the CTek was being able to leave the 240V charger permanently connected without worry of discharge. The manuals wiring diagrams are simply put together.
I must repeat the bit about modern alternators, the expense of a new Ctek arrangement is steep (I reckon) and I want to ensure it will be compatible in the future. Talking to a technician the company is currently working on it.
Will take photos over the Easter break

Cuppa
24th March 2013, 08:54 PM
As I understand it many newer vehicles have alternators which put out voltages too low to effectively charge 'house' batteries, restricting the charge voltage to a little over 13v, enough to replenish the crank battery ready for the next start only. I believe this is to help reduce fuel consumption & that dc to dc chargers are a good solution on these vehicles to charge 'house' batteries. However I would be surprised if a vehicle like a Patrol, commonly fitted with a dual battery system, would have such a 'restricted' alternator ...... but you never know. Let us know when you get a chance.

Cuppa

3kids
24th March 2013, 09:32 PM
Spoke to a CTek tech recently and he was the one who alerted me to the issue. The dual battery arrangement sort of works (but not to 100%) as the wire gauge is usually substantial and proximity to alternator is less than 1 metre away if mounted under bonnet. Batteries mounted in the rear potentially wont recieve adequate voltage to charge properly without it being stepped up.
Just looked up the Red arc product and it seems brilliant, the one bonus I see straight up is the 40 Amp input meaning 480 watts of solar panels can be hooked up. Allowing for losses means you could push your luck to 500 watts. The only down side is at this address http://www.exploroz.com/Forum/Topic/81225/Redarc_versus_C_Tek_DC_Charger.aspx

Cuppa
24th March 2013, 10:07 PM
Have sent you a PM Dave.

I presume the downside to which you refer is the higher voltage at which the Redarc begins to charge. I believe this makes a negligible difference in the real world.
In the link you posted, folks talk about the Redarc being expensive, but I found it to be cheaper than the Ctek 250 Dual +Smartpass. (I paid $450). I must admit I also found it a bit easier to understand what the Redarc did, & was a tad confused about the Smartpass, & the need for two separate 'boxes' when Redarc could do the same with one. Admittedly the Ctek with the smart pass allows for greater current (up to 80 amps ) than redarc's 40amps, but 40 amp was more than sufficient for my needs. The one thing which I found a bit odd about the redarc is that it floats the batteries at 13.2v -13.3v once it has reached a charging voltage of 14.4v-14.5v, a fair bit lower that the 13.6v that my Morningstar Tristar solalr regulator that I have in our bus, but I can't really see that this is likely to be a problem. Not sure what float voltage is with the Ctek.
For me a major advantage with Redarc is their excellent after sales technical service.

Cuppa

3kids
24th March 2013, 11:09 PM
I think the main thing is that they both work and do what they are intended for.
Cheers for the heads up regarding cost of the red arc. I am only borrowing the units I have at present (the lads in question will probably let me keep them as I sort a lot of 240volt problems for them) and it is good to know the prices are extremely similar. My favourite auto spark is a red arc advocate but refuses to get involved with solar. The voltages is the next thing I want to confirm, my suspicion is they will operate slightly lower than specified.
Really looking forward to posting pictures of the rev 1 install and trailer set up

Woof
24th March 2013, 11:21 PM
Hi Dave, mate I have got no idea what you are talking about.....LOL
All I want is a solar system that will let me run my 60 litre Engel fridge/freezer and at the right price.

3kids
24th March 2013, 11:35 PM
Hi Mate,
I will be trialing 3 different panels this Easter weekend at Nanga. I will let you know how I get on.
As usual it will be a budget thing. With batteries it is a case of getting what you pay for.
When I get to work tomorrow I will try and post a PDF doc that might assist.
Also start cruising through E-bay for solar battery chargers. They actually give you an idea on what the lower end units are capable of.
Cuppa is also a wealth of information and his set up and knowledge is impressive.

Woof
24th March 2013, 11:45 PM
Thanks heaps Dave

oncedisturbed
26th March 2013, 09:43 PM
Well the panel came in today and appears reasonable at this stage. I set it up under patio as today was all over the place weather wise and still managed to pump out enough to go from medium to full charge on an 80AH hybrid battery. Looks like that battery is on it's way out as the battery pack meter as well as the mppt controller battery meter both dropped to medium charge afterwards.

The cables look fairly thin so am guessing 20-30 amp (10 B & S??) twin core so will have to go through the site that Cuppa provided on wiring lengths / size and later look at possibly upgrading the controller to a better unit but looks like it will do what we need at this stage, biggest indication will be actually putting it under load and see how it goes as it's mainly the fridge that we use during the day and depending on weather it is turned off before we go to bed to conserve power and use the 2 batteries in the troll for LED lighting.

NP99
13th April 2013, 04:23 AM
Bump guys......:)

BoojaBear
6th June 2013, 09:12 AM
Can any one tell me what is better Amorphous or Monocrystaline panels

threedogs
6th June 2013, 09:51 AM
Mono are way better the other needs to be much bigger to produce the same amps

Cuppa
6th June 2013, 07:26 PM
The commonly available panels are Polycrystalline, Monocrystalline & Amorphous. The modern version of amorphous is 'Thin film' flexible panels, but these are still priced far higher than the other panels & could only be considered an option if cost is not an important factor & the need for flexible panels is paramount.

TD is correct about 'traditional' Amorphous, quite a lot larger per watt which is a problem for folks who want them for mobile installations as the the amount of 'real estate' to mount or store them is limited.

Of Polycrystalline & Monocrystalline, generally Mono is more efficient. Historically it has been more expensive than Poly, but in recent times with the advent of cheap panels on eBay etc the pricing is now quite similar. Efficiency is more important where installation space is limited. On a large home roof without the space limitations of a vehicle Poly may be more cost effective.

I am informed by folks who watch these things, that now might be a good time to buy solar, the industry, internationally, is going through an 'adjustment', & it is quite likely that we will see prices rise in the not too distant future.

Cuppa

threedogs
7th June 2013, 04:02 PM
@ once disturbed, your 80 watt panel should cover your power needs ,
Your LED lighting will use very little power and 4.5ah approx return an hour in good conditions
should cover your fridge use. I take it your battery is 100ah, and thats only one battery
with 2 even better.

oncedisturbed
7th June 2013, 08:04 PM
100w panel with 80ah battery, yet to test it fully


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