To replace my aging backup batteries I bought a new battery for Field Day and portable use.  This is a 12 v 55 AH AGM battery from Gruber Power Services.

http://www.ebay.com/itm/200962020135

To use this along with my portable rig, which is an Icom IC-718, Samlex SEC-1223, and LDG IT-100, I needed something to switch back and forth between power supply and battery when necessary.  I saw the KI0BK Low Loss Power Gate mentioned and bought one.

http://ki0bk.no-ip.com/~pwrgate/LLPG/Site/Welcome.html



There are other similar devices around, but this is the one I bought.  It will switch to battery when AC power is lost and the power supply voltage drops.  When AC power is restored it will switch back to the power supply and charge the battery.  As it gets to full charge it will "float" charge the battery to maintain it without overcharging.

While on that site I also bought the KI0BK SLA Battery Monitor.

http://ki0bk.no-ip.com/~pwrgate/LLPG/Site/SLA_Batt_Mon.html



This device lets you know the state of the battery, fully charged, charging, in use and draining, and voltage too low / stop using.  That low voltage red light is accompanied by an audible alarm from the piezo speaker.  As you know, draining a Lead-Acid battery too low will not only shorten its life, but if low enough, it can totally kill the battery permanently.

I don't know why this excellent battery monitor doesn't have a case like the Power Gate, so I did as suggested in KI0BK's blog and put it in a clear box, which is the same as the blue one with the Power Gate, but clear.  These boxes are made by Hammond and are available from both Mouser and Digikey.

After reading of Piccolo and others using solar battery recharging, I jumped into this myself.

I had bought a 50 watt solar panel.  

http://www.ebay.com/itm/200957552197

This panel is 23" x 26" x 2" thick.  It produces 22 volts no load, and 18 volts under load, and though it says 2.8 amps, it actually measures from 2.0 - 2.25 amps.  Perhaps it'll produce more amperage in the summer sun.  Just today I bought a second identical solar panel, for a total of 100 watts, and 4.0 - 4.5 amps.  This should not only allow continuous RX from the radio while bringing the battery up to full charge, but should keep up with some moderate TX, too.

In between the solar panel and battery I needed a "solar charge controller".  I had purchased an 8 amp "Solarland" model SLC-2408, which works 12 v or 24 v and up to 8 amps.  

http://www.ebay.com/itm/151083804801

In ordering the KI0BK Low Loss Power Gate and SLA Battery Monitor, and asking some solar questions, Jim KI0BK asked if I would test his new Solar Battery Charge Controller.  This is a brand new item.

http://ki0bk.no-ip.com/~pwrgate/LLPG/Site/Solar.html



By the way, this Solar Battery Charge Controller is rated at 20 amps, and is so fused.

Here’s the test setup, a 23” x 26” 50 watt solar panel, the KI0BK Solar Battery Charge Controller, and a 55 amp-hr SLA “Elite” battery from Gruber Power Services.  I had rigged up 12 ga red/black zip cord for this, with Anderson Powerpoles on all connections.  For the main power cord to the transceiver I will be using 10 ga red/black zip cord.



This solar panel puts out about 22 volts no load in full sunlight, and about 18 volts, 2.8 amps under load.  The KI0BK SBCC regulates the solar panel output to safely charge 12 volt SLA batteries.  I had begun charging a few days before, but soon ran out of sunlight.  It did get the battery voltage up 13.4 volts when I put it up for the night.  The next few days were raining and overcast.  Yesterday we had bright sunlight again.

The KI0BK SBCC is rated and fused at 20 amps using a common automotive blade type fuse.  The solar panel input and battery charge output are both Anderson Powerpoles, the de facto standard for EMCOMM.  While I am using red/black Powerpoles for all 12-13.8 volt wiring, I am using green/black for the solar panel.



I plugged in the SBCC, noted the LED was mostly green, but flashing red, and went in for a cup of coffee.  When I came out battery voltage was 13.69 volts.  I puttered around in my shop and by the time I finished the cup of coffee the battery voltage was bouncing around 13.77 v, 13.78 v, 13.79 v, and the LED was green with fewer flashes of red.  





A few minutes later battery voltage stabilized at 13.80 v, full charge and floating, LED almost solid green, with occasional flashes of red.



The SBCC certainly behaved as was described in the instructions and as I expected it should operate.  I could feel no heat from the unit.  

I was really surprised to see how few components, and how small, for such a high amperage rating.  Best of all, I like the small size and low weight which is important for portable gear.

Good timing on this, Jupiter7200.  Thinking of doing something similar for the shack sometime soon.  TU for the info.  

Very nice write-up!

Thanks!!

This thread is full of win!

My initial layout for such a system was to run the radio off the battery as the norm.

A solar panel or AC power was actually just to charge/keep charged the battery.

The only controller I could find that would for simultaneous use and solar charging, without overcharging, was the Morningstar PWM SK-6 charge controller.

Does that controller offer similar functionality?

According to Jim KI0BK, yes, hook it up like this:



(Diagram supplied by Jim KI0BK)


So yes, solar panel and solar controller can be hooked to the battery at the same time as the other equipment, Power Gate, etc.

Outstanding,

Tagging this for future box set-up.

Jupiter, your diagram shows a battery booster.  It that a buck/boost device or something else.  My setup is similar, but doesn't have the LLPG or battery booster.  It runs fine.

This diagram was supplied by Jim KI0BK.  I don't have or want a battery booster.

Jupiter,

very excellent write-up.  am looking at doing something similar myself.  as far as the KI0BK charge controller, do you know what charging method it uses?  couldn't tell from his website.  does it use PWM, or MPPT charging?  any idea from him on release date/pricing?  perhaps i missed it on his page.

also, what made you pick that particular battery?  am trying to learn about the various options in batteries, & wondering how much difference there is b/w brands.  went down to the local Costco the other day, to check out marine deep cycle & golf cart batteries.  think the 6v golf cart batteries were $89 a piece.

I just ordered this:

12V 18Ah SLA

I have an old UPS which used a 12V 7.2aH SLA as it's heart and for now I'll use that AC circuit to keep this charged (the 18aH won't fit inside lol).  I never did use the battery for radio operations though.  Still in the market for an HF rig.

I did once plug the charging stand into the stand alone UPS (not plugged into it in this pic) for the VHF HT and used it like this (the coax goes into the roof Ed Fong antenna)

I'm not sure, but will ask Jim.   I know it changes charge rates, higher for charging, and stabilizes at a float.  The float voltage is adjustable for other battery types.



I previously had two RBC-6 sets.  One RBC-6 is two 12 volt 12 amp-hour batteries.  I had them in parallel for 12 volts 24 amp-hours.  Another RBC-6 set in parallel gave a total of 48 amp-hrs.  My idea on that was that I could use one pair, and charge the other, or remove/replace any of the four if one went bad.  That just hasn't happened.  

I went with this size because it is as much as I want to carry around for this purpose.  This one is 37 lb.

I would not recommend deep cycle marine as these AGM batteries are actually more "deep cycle" than the deep cycle marine types.  Also, SLA, AGM, Gel Cell, no spillage of acid and no hydrogen/oxygen gassing during charge and over -charge.   It is not recommended to use any type of flooded battery for our (ham radio / solar) applications.  That's just more than I want to risk.  

With the solar panels supplying 4-4.5 amps in bright sun, or even if only 3 amps, that is sufficient to keep up with 1-1.5 amps drain during receive and even build charge back from moderate transmitting.

thanks for the info on the batteries.  clearly, i need to research this more before committing any $$.

as far as chargers go, am putting a couple youtube links here, by some EE nerd who does pretty good vids on his home solar setup.  he's discussing PWM vs. MPPT chargers, & their relative pros/cons.  first vid is shorter, & just shows him flipping an A/B switch to compare charging Watts b/w the two types of chargers, given same solar panel/sunlight.  2nd vid goes more in-depth into the technology behind the two, showing their relative efficiencies.

1st vid, ~2min long:
https://www.youtube.com/watch?v=QpL4RR0_QyM

2nd vid more in depth w/ calcs, graphs, discussion of models & their costs, etc.
https://www.youtube.com/watch?feature=player_detailpage&v=8-Z8gXaHozg#t=416

looks like the cost b/w the two techs is approaching parity.  seems w/ PWM output is tied to battery voltage, whereas MPPT separates panel from the battery load, & varies I & V (if battery V is low, you get more I, & vice versa), maximizing your power into the batteries, for a given solar panel wattage.


ETA: snipped for brevity & URL edit for time

Here's an excellent primer on the subject, including batteries.

http://www.youtube.com/watch?v=8SuvAKZt0Vs

You were the person I thought of when I saw this thread.

that is most excellent.  he answers a lot of the charge controller questions i had starting @ 30:00.  saved that for repeat viewing.  appreciated.

What is the "Battery booster" and will the PS trickle charge the battery?

The SK-6 is what I use. It's a fantastic little controller.

I also have a Steca solsun 6, which has a low voltage disconnect feature, but it can't run much amps through the connection.

Battery boosters are step-up switching power supplies, they take whatever they get and put out 13.8V.
Most rigs don't give you full power out if the battery voltage sags -- which it will under high power.

I use the MFJ 4416. When we did our emergency power net that's what let me run 80W out on digital,
there's no way that would have happened without the booster.

Yes, the solar charge controller will trickle, then "float" the battery.

Also, via the Low Loss Power Gate, the power supply, if A/C is available, will charge the battery, then as it comes up, switch to a trickle, then "float" the battery.

Jim replied:

tag

appreciate the update/info.  always more to learn in this hobby.

tag

Piccolo gave some guidance on all this.  I figured if he could do it, anybody could.    No, seriously, Thanks, Picc!  I had wondered how "long term" we could keep up under such conditions, and Picc did this at the National Matches, running all week with a special event station between his times up at bat.

My point, so far, is that I got into this knowing little or nothing except what my general battery requirements would be from experience operating from battery for some special events and Field Day.  

I could compute my power and recharging needs.

The rest, I'm figuring out as I go with some suggestions I've picked up from others.  I think the punch line is, if I can figure this out and get a system up and running, so can you.

In my opinion, I think it starts with battery requirements, not the solar panel.  And don't look at transmit amperage alone... you don't transmit 100% of the time, nor do you, in an emergency net transmit at 100% power.  You might, you might not.  As is "good amateur practice" you use the minimum power needed for a good contact.  

From Field Day I know that a fellow ham's Ten-Tec Scout, at only 50 watts SSB, is just about as effective as my Icom 718 at 100 watts SSB.  So a 50% reduction in transmit power is a start.

But calling "CQ Field Day, CQ Field Day..." and working an emergency net is two different things.  Where a net control (who should have some reliable AC power to be net control) might TX 20% of the time, while others are reporting in the other 80%, he might do this for some hours.  But for the rest of us out in the hinterland we will be like good children and speak only when spoken to.  We might monitor most of an hour, and give a quick report, IF we have one.  I would doubt that in such a case I would need to run my mouth transmit more than 2 or 3 minutes in an hour.  5% transmit time.  But I might monitor for 8 hours at 1-1.5 amps draw.  I would need to be able to keep up with that and rebuild some charge from transmitting.

I could physically unplug an AC power supply, and plug a battery into the system.  I could switch via a toggle switch... or better, a big knife switch on the wall with cobwebs and some sparks.   Hahah.  Or best, one of these battery backup modules handling this chore automatically and seamlessly.  There are others, not just the one I used.  Offhand I can think of several.  Samlex, Astron and West Mountain Radio make battery backup modules that do the same as the Low Loss Power Gate (blue box) at the top of this thread.  And Samlex has a backup module built into their new SEC-1223BBM power supply.  There are others on the market.

A solar charge controller is needed between the solar panels and battery to regulate voltage to correct charge / float voltage for the battery.  It needs to be rated high enough voltage and amperage to handle what the solar panel puts out.  There are many available from the various solar power companies that sell solar panels.

Also needed is a way to monitor the battery to look for state of charge, but more importantly, so that you can know when you are getting dangerously low and should shut down and recharge.  Discharging a lead-acid battery too far can permanently damage it.   I won't regurgitate voltages and such here, you can find that information easily enough.  But anything from a simple volt meter, and some knowledge of charge level vs. voltage to a more sophisticated battery monitor and alarm, perhaps auto-shutdown device, can help avoid or prevent such damage.

Finally, solar panel or panels (they need to output the same voltage) of sufficient size to reasonably recharge the battery, as well as do this while also producing enough energy to run the radio on Receive.  Allowing 1.5 amps for monitoring (receive) current, I would think at least 2 more amps over that, possibly 3 amps more would be good (total 4-4.5 amps).  But consider that you might, at best, only get 70% of the rated current from the solar panel.  That's been my experience so far.  From my 50 watt panel with a 2.8 amp rating I'm actually measuring 2-2.25 amps.  From this I saw that I needed at least 100 watts worth of solar panels, so I ordered a second identical panel.

This is where things stand so far.  I have since run my radio gear during an afternoon, just monitoring.  When I closed down and put the battery back on the Battery Tender the light turned green in just a few minutes indicating the battery was charged and floating.  So, the system as it stands now will keep up.

Next step is to integrate this into my portable kit.

Well, that's about it.

------

No, there's more.  Since writing the above summary I found this.  From what I read here, it seems that many of my assumptions and calculations are in the ballpark.

http://www.ctsolar.com/solarpowerforamateurradiofaq.aspx

In fact, according to the above page, I should be able to run this setup even harder than what I anticipated, or looking at it the other way, what I have chosen, battery, solar panel size, will easily and quickly recharge, and should keep in good shape to operate day after day.

Bump to prevent archiving.

Thanks for the plug Jup, and thanks for the kind words generalissimo (this one is my video)

I knew the creator of that video was an Arfcommer, I just couldn't put his call sign with a user name when I posted it.  

I know now.

Great job on the video, Echo!

Echo,
I'm still waiting for an update on your Genasun vs Buddipole charge controller. Any insights you can provide about those would be awesome.

Also, everyone may be interested in your information about the Powerfilm solar panels. http://www.powerfilmsolar.com/products/?foldable_solar_panels&show=category&productCategoryID=6579&productCategoryIDs=6578,6579

Yes, most definitely!  Looking to solar recharge LiFePO4 batteries for the KX3 in the near future.  

How satisfied are you with the solar panel, considering cost vs quality?

Any opinions on these two solar panels?

http://www.amazon.com/Instapark%C2%AE-Mercury27-Portable-Automotive-Batteries/dp/B00EVFEBKU/ref=pd_sim_sbs_cps_2?ie=UTF8&refRID=1K5HTDQ7EYJBC7A5B60H


http://www.amazon.com/Allpowers-Portable-Folding-Blackberry-bluetooth/dp/B00G6CDTGS/ref=sr_1_4?ie=UTF8&qid=1392849409&sr=8-4&keywords=folding+solar+panel


They're approximately the same size and rating as the Powerfilm equivalents but at half the price.

So I wonder .........

Powerfilm told me (email) that their folding panels are not water resistant rated.  Their roll up panels are.  But the equivalent roll ups take up more space in a pack.

I'm going to start a new thread so I don't hijack Jupiter7200's thread.  Look for this later tonight or tomorrow!

Very happy.  You can get 100w worth with two 50 w panels wired parallel, or with one large 100 w panel.  There is also a deal with panels and solar charge controller.

http://www.ebay.com/itm/200957552197    I have two of these.  They are also sold as a pair with a solar charge controller.

http://www.ebay.com/itm/200922556553    This is a single 100 w panel, no charge controller, just the panel.

http://www.ebay.com/itm/171057040362    This is the same 100 w panel with solar charge controller.  This is a very good buy.

You may find it easier to transport two 50 watt panels vs. one 100 watt panel.

You can find more here:   http://stores.ebay.com/ML-Solar-World-Wise-Solutions?_trksid=p2047675.l2563

Both of these are rated only 16-18 volts open circuit.  What is that under load?  Will it be enough to charge your batteries?  Perhaps Echomancer can answer this better than I can.  

My panels are 22 volts open circuit, and 18 volts under load.

They are only resistant, so need to be pulled in under rain...

At the end of the day, anything above the battery voltage is OK.  This is essentially a big difference between PWM Charge Controllers and MPPT.  PWM CCs "load" the panel at the battery voltage, so it isn't running at that high voltage anyway.  MPPT CCs separate the circuits so that it can choose where to best load the panel for the best power output (not optimizing for voltage OR current).  Does this make sense?

Honestly?  Both of those panels look like the first generation Goal Zero Panels.  If they are, I would skip them.  I have run tests that they don't produce their optimum output even under the best of conditions.  For instance. the rating is the rating for the panels WITHOUT the protective coating over the PV cells.  The 27 watt panel I was only able to get about 11-15 watts out in the best of times.

Goal Zero's newer panels do perform better.  The power film panels perform the best, but they are not as durable.  The GZ panels can literally be run over and they keep on ticking - so that's what you'e choosing.

glad to be of service.