Solar briefcase generator

[Liz]

Was strolling around Kmart this arv, to escape the heat, when I came across one of these

http://cgi.ebay.com.au/Solar-Generator-Briefcase_W0QQitemZ360177446013QQcm dZViewItemQQptZLH_DefaultDomain_0?h ash=item53dc3fac7d

.. looked pretty cool, converts solar power into 12v supply, and costs $119. Nearly bought it, but thought I would just check with you guys.
Will be using with my NEW Argo Navis, when it arrives.
Will I get it??
Also picked up one of those foam bedrolls, to try and make a dew shield :)

[TrevorW]

Only has 750mamp output so will take a while to recharge a 12v battery

[Liz]

Hmm ... thanks Trevor. How long is a long time? 1 day? I havent had anything to do with solar .... oh, apart from some nifty solar paper lanterns which shine brightly for hours and hours!!

[TrevorW]

depends on the amp hour of the battery and how flat

I have a 12v 15amp hr jump starter battery that has a 500 mamp power adapter takes at least 30 hrs to recharge

[mswhin63]

I am currently working on an plug and isolation for my car, as we travel to dark sites why not use the juice from the alternator in car to charge the obs batteries. The alternator primarily only supplies the battery to top up or usually at night for the extra consumption of lights etc.

I remember one battery died while driving sometime ago time. I was able to drive all the way home just on the alternator and regulator. So much for the battery.

[Liz]

..... geeze Malcolm, you know how to scare a girl!!!

[mswhin63]

Lucky I was driving during the daytime, tried to turn on the lights and the car nearly died.

[mithrandir]

You want a proper dual battery isolator. It will correctly charge the battery while you drive and not discharge the main battery if you choose to leave it in the car when you get to your obs site.

[TrevorW]

Mal this is what you need I think

http://www.powerstream.com/DCC.htm

[Spanrz]

I have these things (2 of) The newer version and the older version.
The EBAY one featured is the older model and 12v only. Which by memory is old stock if any one has them.

Best thing since sliced bread.
The later one charges 12v and 24v, the earlier charges 12v.

I had 4 batteries (80ah-100ah each) The 24v worked brillantly.
I had a large 60lt waeco fridge (draws 7a at 12v, 3.5 at 24v), a laptop, 300w inverter and a large HID 24v 70w lamp (draws about 6amps to start then 1-3 amps running)
I ran this setup at Bathurst for the week. Never failed, never ran out of battery charge.

I also did a test as well, they work in full sun at at nearly an amp, slight cloud cover, reduces the amps a little, but full voltage.
They will still work in heavy cloud, but amps is low and voltage reduces a lot.
Heavy cloud, probably runs at 30-50% of it rating.

Do your sums on your current draw. Then work out a plan.

EDIT:

PIC (The one on the left is the 24v the other on the right is the 12v only one)

http://farm3.static.flickr.com/2765/4284132171_def96a15af_b.jpg

[Liz]

Thanks Brett ..... the one on ebay was just an example. The one I am looking at is at Kmart, and I presume would be the older model as well.
You did great with both yours.
Might be worth a go then. :)

[mswhin63]

Thanks for that Trevor, just what I am looking for.