Rising Sun Member Forums

Rising Sun Member Forums (http://www.risingsun4x4club.org/forum2/index.php)
-   Ham & CB Radio Corner (http://www.risingsun4x4club.org/forum2/forumdisplay.php?f=20)
-   -   Battery Box (http://www.risingsun4x4club.org/forum2/showthread.php?t=20592)

Keith 12-08-2013 08:50 PM

Battery Box
 
So… I plan on making a few "battery boxes" in the coming months. Thought I'd start a thread to share my progress and get input.

First one I'm building will be to use for emergencies and to test out HAM and other 12V DC stuff at home without messing with the truck. My original motivation for building one of these was when I realized all HAM stuff runs on 12V DC and I think I'd rather buy a couple batteries than an almost as expensive AC to DC converter to run HAM radios at home.

Anyway, this first one is going to be built around 2 x 50 Amp Hour batteries. I got a screaming deal on these: http://www.batterystuff.com/batterie...500-45977.html

I also picked up one of these: http://www.batterystuff.com/battery-products/g3500.html

That's all I can really afford for the month, but my eventual plans are to build a plywood box to house the 2 batteries. My plans for outputs are probably about 6 power pole outlets, 2 USB outlets, and one cig lighter output.

For power input I plan to permanently mount the above controller/charger and a solar controller. I'll likely end up plunking this down in the garage with it connected to a 60 watt solar panel. I have said 60 watt panel on my truck now but plan to upgrade it to a 100 watt in the Spring.

DaveInDenver 12-08-2013 09:13 PM

KC0YRM and I found at Field Day 2012 that a generator is the way to go. Battery based emergency power is fine but short term, a day or so, but longer than that or significant operating time and you quickly deplete them. If you intend to continue operating you need to size the recharging capacity to be something like twice the operating use. IOW, if you are consuming 120W per hour (say roughly a 100W HF station operating 50% duty cycle during a contest) from the storage and you have 1200W-hr available you can go 10 hours. But you need to plan on using zero storage during the day light (if using solar) and rebuilding the reserve simultaneously, which means you need 240W during the summer when you have 12 hours of sunlight. In the winter if you get 6 hours of good sun you need more like 400W of solar to run deep into the night. Brian's 1000W generator was awesome...

rover67 12-08-2013 09:54 PM

I have a TON of batteries you can have to get a huge amount of capacity. free.

Keith 12-08-2013 10:03 PM

Dave, I plan to build a few of these. The one above will be for testing purposes mostly and will probably run a 2m radio in my garage. The next couple I plan to build around 2 x 100 amp hour batteries and I plan to hook them up to 2 x 100 watt solar panels.

A generator is too easy…

Marco, you got any that are AGM (gell cell)? For the ones in boxes I don't wanna have to deal with corrosion and venting. But might be interesting to see what we could come up with using a whole mess of old car batteries to make a franken-rig.

rover67 12-09-2013 08:33 AM

They are sealed batteries that we use at work to power our mobile CT scanners. I grabbed 15 of them that were being replaced during PM. They are all about motorcycle sized batteries.

DaveInDenver 12-09-2013 08:41 AM

There is a ratio of solar panel to capacity that's required to keep them fully charged. I run roughly 2x panel capacity to battery size because the panel will only produce full power with proper incident light which only happens if you track the sun and if it's above the horizon enough. In the winter I might get a couple of hours of full charging from my panel (which have historically just been roof mounted at home), which is a 24V panel to-boot. In the summer it's a lot better, the battery stays topped a lot better.

Those batteries Marco has are probably perfect being SLABs. If you need to condition them I can do that, although I doubt they do.

Generators get the same multiplier as mains powered stations, so I do guess it is too easy. OTOH it's sure a lot easier to run your house fridge during longer power outages...

Keith 12-09-2013 08:47 AM

Quote:

Originally Posted by rover67 (Post 243249)
They are sealed batteries that we use at work to power our mobile CT scanners. I grabbed 15 of them that were being replaced during PM. They are all about motorcycle sized batteries.

Sweet! I'll stop by and take a look sometime soon… Any way to measure their capacity? Can we just attach a known load and see how quick they drop?

Maybe use one of these: http://www.powerwerx.com/digital-met...owerpoles.html

Keith 12-09-2013 08:54 AM

Quote:

Originally Posted by DaveInDenver (Post 243250)
Generators get the same multiplier as mains powered stations, so I do guess it is too easy. OTOH it's sure a lot easier to run your house fridge during longer power outages...

On some level I do want this around in case of a prolonged power outage, but it seems like that hardly ever happens in Colorado. Mostly I just wanna fool around with solar technology. If we did have a really long power outage, I could put everything we really needed from the fridge into my Edgestar and run it off the truck or off one of the 200 amp hour / 200 watt systems.

I will say it would have been really nice to have one of the 200-sized systems built up this summer to be able to drop it off to some of my friends up in Lyons who didn't have power for a few weeks.

DaveInDenver 12-09-2013 09:09 AM

Think about capacity. 200A-hr at 12V is 2400W-hr. That is what is available from one regular household outlet. Sum up what you're running 24/7 and consider that you only get to charge during daylight. I run the Engel around the clock when we lose power, which consumes around 50W-hr when set to freeze. It runs pretty continuously. That along with a radio on receive is about 65W-hr and I will draw down my 100A-hr battery in about 15 to 18 hours. I put 240W-hr back into the system with my solar panel and can run continuously unless we get more than one day of continuous overcast.

Keith 12-09-2013 10:44 AM

The math I did showed I could use it (The 200 watt and 200 amp-hour system) to run an Edgestar at 40 degrees farenheit for about 2 days. (It draws about 1200 watt-hours per day under normal conditions in the summer.) And that it would take about 12 hours of direct sunlight to fully recharge the batteries. So, assuming I can get 12 hours of sun every two days, I'm good.

Obviously, that would be cutting it close in the winter, but it's also not very hard to keep food cold in the winter. Most of the time, I will be using it to run my home network, desktop computer, and any HAM stuff I have in the house. That draws about 1,000 watt-hours per day. If we don't get a lot of sun for a couple days, I can always just plug in the battery charger at night.

I will also be building one of these for someone who wants to use it to run a fridge for camping trips where he won't always have the option of running stuff off his alternator. I figured that 200 amp-hours and 200 watts would be the minimum to guarantee that the system will keep his beer cold about 95% of the time.

Of course, all of this is pretty theoretical. We'll see what happens when the rubber meets the road.


All times are GMT -6. The time now is 06:52 AM.

Powered by vBulletin® Version 3.7.1
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.