Announcement

Collapse
No announcement yet.

Need some basic knowledge before i dive in

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Need some basic knowledge before i dive in

    Hello, I am very new to solar, i understand the basics but would like to know a little bit more, some of this may be elementary.

    My main focus is mobile solar, out in the field and need to charge my R/C airplanes.

    I have a LiPo charger that is DC input not AC and can charge 4-6 batteries at a time, a 12V car battery is max of 500 watts. Now if i use a AC plug on that charger i get 1800 watts (estimated) so will that mean the the charger will take longer on the DC ?

    My main goal is to not build a solar panel to the minimum, i would like to build it to allow transport on my car, get to the field and open it up but allow 5 or 10 others to plug into my system to charge without restrictions or even plug in a drill, light who knows a mini cooler maybe ?

    Hope that makes sense and thank you in advance
    Attached Files

  • #2
    This is what I built to charge my RC LiPo's. It has a 65Ah Optima Blue Top battery and an 80 watt folding pv panel with a cheap 15Amp PWM CC. I found a battery box on amazon along with a hand cart and hardware. It cost about $550 to make but you can probably do it for less now. I would also go with a 100 watt panel which is better match with that 65Ah battery.

    For AC loads I have a cheap 250 watt inverter. It is easy to load in my car or truck and easy to drag to the field where I flew.

    Here are a few pictures.

    Comment


    • Guest's Avatar
      Guest commented
      Editing a comment
      Hey SunEagle I noticed your thumbnails when I click on them don't get any bigger . Is that how its supposed to happen? When I posted pictures I noticed the options of display size but assumed the pictures would go up full size and display as thumbnails if chosen and the open to full size if clicked?

  • #3
    give up on the mini cooler, the battery will not support that along with the other loads.
    Size/space, do you have a mini-cooper or a flex van ? The transport vehicle will be the deciding factor on the PV panel size. Or you can put 2 small panels together with a piano hinge and unfold it. Don't forget a transport dolly
    Powerfab top of pole PV mount (2) | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister

    Comment


    • #4
      Originally posted by Mike90250 View Post
      give up on the mini cooler, the battery will not support that along with the other loads.
      Size/space, do you have a mini-cooper or a flex van ? The transport vehicle will be the deciding factor on the PV panel size. Or you can put 2 small panels together with a piano hinge and unfold it. Don't forget a transport dolly

      I was thinking of something like this that i unfold.

      Semi-flexible-100-font-b-watt-b-font-sun-power-sunpower-font-b-solar-b-font.jpg

      I have Ford Flex van, i can store the batteries inside the van, but that's where i wanted to get to if i want to theoretically power up a mini cooler would this be possable by adding more oalr panels, but i don't think the number of solar panels to what i want to power would make a difference, correct ? what i mean is if one panel is 12V 40 watt and the battery is 12V it would charge the battery but slow in comparison with more panels in parallel to keep the volts the same but watts double.


      Comment


      • #5
        Originally posted by SunEagle View Post
        This is what I built to charge my RC LiPo's. It has a 65Ah Optima Blue Top battery and an 80 watt folding pv panel with a cheap 15Amp PWM CC. I found a battery box on amazon along with a hand cart and hardware. It cost about $550 to make but you can probably do it for less now. I would also go with a 100 watt panel which is better match with that 65Ah battery.

        For AC loads I have a cheap 250 watt inverter. It is easy to load in my car or truck and easy to drag to the field where I flew.

        Here are a few pictures.

        Hi Sun Eagle, how long does your Optima take to charge with the 80watt and how long does the Optima take to get below 40% power with your LiPo batteries plugged in when your Optima is not connected to the solar grid ?

        Comment


        • #6
          You need enough solar to power your loads, and you must recharge the battery within 48 hours or risk sulfation
          Powerfab top of pole PV mount (2) | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
          || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
          || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

          solar: http://tinyurl.com/LMR-Solar
          gen: http://tinyurl.com/LMR-Lister

          Comment


          • #7
            Originally posted by Tesla View Post


            Hi Sun Eagle, how long does your Optima take to charge with the 80watt and how long does the Optima take to get below 40% power with your LiPo batteries plugged in when your Optima is not connected to the solar grid ?
            Hard to tell. I have never really discharged the Optima below 50%. Also that 80 watt panel is undersized since it has an Imp of ~ 4.5amps and I should be using a panel with something around 6.5amps or around 120watts.

            If the solar panel did not keep it topped off I would usually use my 12volt Schumacher battery charger when I got home.

            Comment


            • #8
              Originally posted by Tesla View Post

              My main focus is mobile solar, out in the field and need to charge my R/C airplanes.

              I have a LiPo charger that is DC input not AC and can charge 4-6 batteries at a time, a 12V car battery is max of 500 watts. Now if i use a AC plug on that charger i get 1800 watts (estimated) so will that mean the the charger will take longer on the DC ?
              More Power = Shorter Charge time. But that is the least you have to worry about. Look I am an RC pilot and I know every peice of equipment you use. Short story here is you are going to be dissapointed. Solar is not going to work out, seen to many go down that road with the exact same results. Never worked.

              The reason it will not work is you cannot carry enough panels to generate any meaningful amount of energy. The correct route to take is to use Deep Cycle golf cart batteries at home, and take them to the site with jumper cables to charge periodically from your car. Even if you tried solar, still requires the same massive battery. You would need 1000 watts of panels to actually generate enough power to keep the Deep Cycle Battery charged up.

              So get some decent Golf Cart Batteries and a charger. Save your coins going solar and skip it as it is throwing money away.
              MSEE, PE

              Comment


              • #9
                Originally posted by SunEagle View Post
                If the solar panel did not keep it topped off I would usually use my 12volt Schumacher battery charger when I got home.
                I hope that's not a "speedcharger" model. You know how I feel about those. If it is, you know the work-around for it right?

                Comment


                • #10
                  Originally posted by PNjunction View Post

                  I hope that's not a "speedcharger" model. You know how I feel about those. If it is, you know the work-around for it right?
                  Hmmm. Actually it is the 80Amp version model SC-8020A of the speedcharger. I got it for my AGM battery system.

                  I do keep a close eye on it while I charge any of my batteries but please remind me of the proper work around.
                  Last edited by SunEagle; 11-29-2016, 10:12 AM. Reason: added model number

                  Comment


                  • #11
                    Uh oh.

                    The speedchargers are overly-agressive to batteries in normal shape that just need a charge, about 0.7v over-spec for any chemistry. Details are important. A voltmeter placed at the *terminals* tells all.

                    Because of that, this series of chargers are the ONLY ones out there, where I recommend purposely using the wrong chemistry setting for agm. That is, purposely select GEL for agm charging. This also means that they are not useful for gels as there is no lower setting available.

                    Normally gel is rated at about 14.1v when done right. BUT since the speedchargers are overly-agressive with the 0.6v or so over-spec, the gel setting is about right for agm since when using gel, the CV is actually about 14.7v. Ok for an Optima, but a true gel will just cry rice-crispy tears.

                    AGM's are spec'ed normally run at a CV of about 14.6v max, but the speedcharger takes that to 14.6 + 0.6, or about 15.2v. That is NOT good for most agm's.

                    What makes the situation crazy is that in some instances where the speedcharger has a voltage display, it is not accurate at all! Heh, you may see 14.6v on the display, BUT your terminal voltage is in the low to mid 15's. !!

                    At first, I thought it was just the unwashed masses that didn't know about how a CC/CV charge algo works when online reviews show them hanging endlessly at around 80% on the display, and then suddenly showing 100% charge upon disconnect / reconnect.

                    So I bought quite a few of them for testing from lunchbox to desktop units. Holy cow! That hang at 80% was due to the CV being in the high-15's, but not at the end of a CV stage, but right at the beginning! No wonder my agm's stalled like so many others as it just gassed and could never complete the absorb - unless a timeout took over. You'll note that Optima's are rated to accept 15+ volts, but ONLY for very very quick charge like at the drag races - cycle life suffers badly of course, but yeah, it works.

                    NOTE: Die-Hard "platinum" chargers, also made by Schumacher, have special firmware designed for Enersys/Odyssey agm's who get the spec right! But the generic non-platinum versions go way over-spec! Yeah, I checked that out too. Lot of bucks spent on chargers, believe me.

                    To top the mystery off, all off the desktop units did kind of a 50-50 duty cycle, such as the 8020 as you hear the fan unit kind of grind up and down over the course of charging. Putting an ammeter on it, showed that for one groan-cycle, you charged at 20A, and then it alternated at 50%, or 10A, and then back to 20A again over and over. But here's the trick: It is only accurate spec-wise for HALF the cycle - the other half goes over-spec in voltage! The lunchboxes just go over-spec all the time.

                    IF the speedchargers went over-spec at the END of an absorb, I could have possibly justified them as a specialty limited "EQ" type of charger. But, if you also place an ammeter inline, you see that the higher voltage is not at the end, but near the start of absorb. Ooops, that just spins the tires until a timeout occurs, or one starts wondering if the online reviews from the unwashed masses was right!

                    So basically, they do the job they were designed to do, for a dead piece of lead in the garage that needs a kick in the pants. Normal batteries, not so much!

                    So please, for this series of chargers only, please use the GEL setting for your Optima (or any other agm), due to the overly-aggressive nature of it. But don't trust me, put your own voltmeter on the terminals and do a min/max hold. Surprise!
                    Last edited by PNjunction; 11-29-2016, 04:29 PM.

                    Comment


                    • #12
                      Originally posted by PNjunction View Post
                      Uh oh.

                      The speedchargers are overly-agressive to batteries in normal shape that just need a charge, about 0.7v over-spec for any chemistry. Details are important. A voltmeter placed at the *terminals* tells all.

                      Because of that, this series of chargers are the ONLY ones out there, where I recommend purposely using the wrong chemistry setting for agm. That is, purposely select GEL for agm charging. This also means that they are not useful for gels as there is no lower setting available.

                      Normally gel is rated at about 14.1v when done right. BUT since the speedchargers are overly-agressive with the 0.6v or so over-spec, the gel setting is about right for agm since when using gel, the CV is actually about 14.7v. Ok for an Optima, but a true gel will just cry rice-crispy tears.

                      AGM's are spec'ed normally run at a CV of about 14.6v max, but the speedcharger takes that to 14.6 + 0.6, or about 15.2v. That is NOT good for most agm's.

                      What makes the situation crazy is that in some instances where the speedcharger has a voltage display, it is not accurate at all! Heh, you may see 14.6v on the display, BUT your terminal voltage is in the low to mid 15's. !!

                      At first, I thought it was just the unwashed masses that didn't know about how a CC/CV charge algo works when online reviews show them hanging endlessly at around 80% on the display, and then suddenly showing 100% charge upon disconnect / reconnect.

                      So I bought quite a few of them for testing from lunchbox to desktop units. Holy cow! That hang at 80% was due to the CV being in the high-15's, but not at the end of a CV stage, but right at the beginning! No wonder my agm's stalled like so many others as it just gassed and could never complete the absorb - unless a timeout took over. You'll note that Optima's are rated to accept 15+ volts, but ONLY for very very quick charge like at the drag races - cycle life suffers badly of course, but yeah, it works.

                      NOTE: Die-Hard "platinum" chargers, also made by Schumacher, have special firmware designed for Enersys/Odyssey agm's who get the spec right! But the generic non-platinum versions go way over-spec! Yeah, I checked that out too. Lot of bucks spent on chargers, believe me.

                      To top the mystery off, all off the desktop units did kind of a 50-50 duty cycle, such as the 8020 as you hear the fan unit kind of grind up and down over the course of charging. Putting an ammeter on it, showed that for one groan-cycle, you charged at 20A, and then it alternated at 50%, or 10A, and then back to 20A again over and over. But here's the trick: It is only accurate spec-wise for HALF the cycle - the other half goes over-spec in voltage! The lunchboxes just go over-spec all the time.

                      IF the speedchargers went over-spec at the END of an absorb, I could have possibly justified them as a specialty limited "EQ" type of charger. But, if you also place an ammeter inline, you see that the higher voltage is not at the end, but near the start of absorb. Ooops, that just spins the tires until a timeout occurs, or one starts wondering if the online reviews from the unwashed masses was right!

                      So basically, they do the job they were designed to do, for a dead piece of lead in the garage that needs a kick in the pants. Normal batteries, not so much!

                      So please, for this series of chargers only, please use the GEL setting for your Optima (or any other agm), due to the overly-aggressive nature of it. But don't trust me, put your own voltmeter on the terminals and do a min/max hold. Surprise!
                      Good information. I have used both my DC ammeter and voltmeter when I charge because like you do not trust the meter on the charger. I have noticed that the charger shows a lower voltage then my voltmeter which is why I keep a close eye on it and always wondered why it went above 15vdc. It would also hang at 80% for a long time and then like magic go to 100% SOC like you said. Not something I thought was right but what works perfectly?

                      Good idea about using the GEL setting. I will be doing that the next time I give both my AGM's and Optima a wake up call.

                      Hmm. I've been asked a few time by the wife what I want for Christmas. Maybe now is the time to get a better charger. Doesn't someone suggest the NOCO Genius as a type to look at?

                      Comment


                      • #13
                        Originally posted by SunEagle View Post
                        Hmm. I've been asked a few time by the wife what I want for Christmas. Maybe now is the time to get a better charger. Doesn't someone suggest the NOCO Genius as a type to look at?
                        As a type, it is the typical automotive one that doesn't really do a full charge on agm's. That is, it performs a "float monitoring" mode, which means that after absorb, it basically assumes you are going to put it back into the vehicle for a quick SLI discharge and a good followup from the alternator to get that last 1% charged. For something like your stand-alone Optima, that merely means it never gets a true full charge, and is allowed to sulfate / self discharge to a lower voltage trigger threshold. Slowly, this walks the capacity down.

                        And for high-performance pure-lead agm's like Optima and Odyssey, I'm not so happy with the stepped-current charging. This is fine for standard lead-calcium agm's, but in the long run, babying a pure-lead, although it looks good on paper, is not so good for overall life.

                        However, the larger ones include a 13.6v "maintenance" or power-supply mode (careful, see the safety precautions), where one in our situation could manually give it a good float for 12 or more hours to actually finish the charge, rather than sit in a capacity reducing float-monitoring mode. QC with the newer models has been a problem for me.

                        There are a lot of good chargers out there, but one has to look very carefully, or be willing as I do for education to buy them, observe them, and keep or recycle as necessary. Kind of an expensive at-home education.

                        Optima's own chargers are actually very good with their algo. They DO charge properly up to spec, and get this - *finish* absorb before giving it a "conditioning" charge, which is properly done AFTER absorb is finished instead of jumping the gun like some other do. They will do this every 30 days if you leave it connected. That is good.

                        Considering that most people never give their agm's a proper initial extended-absorb "freshening" charge in the first place (usually 12-24 hours of say 14.4v absorb, even if no current is really flowing), then Optima's shorter, and slightly higher voltage "conditioning", after absorb is finished, is beneficial.

                        The smaller 4A model would be fine for topping off, and the larger one for deeper discharges. Either one is fine for maintenance obviously. A bit pricy, and while not made of metal like the good old days, at least the algo is correct.

                        They don't go into as fine a charging algo detail as I like in their documents, so I bought them to find out, and was VERY pleased with what I saw. Hint: with mine, I was initially frustrated at not being able to select the different battery types with a button hold. Found out that tapping your selection once the bouncing led actually illuminates upon your choice, rather than just holding it down forever, activated it perfectly every time.

                        There are many options out there if you can get hold of charger specs and actually vet them yourself. For an Optima, a no-brainer stocking stuffer would be one of their own chargers.
                        Last edited by PNjunction; 11-29-2016, 06:41 PM.

                        Comment


                        • #14
                          Originally posted by PNjunction View Post

                          As a type, it is the typical automotive one that doesn't really do a full charge on agm's. That is, it performs a "float monitoring" mode, which means that after absorb, it basically assumes you are going to put it back into the vehicle for a quick SLI discharge and a good followup from the alternator to get that last 1% charged. For something like your stand-alone Optima, that merely means it never gets a true full charge, and is allowed to sulfate / self discharge to a lower voltage trigger threshold. Slowly, this walks the capacity down.

                          And for high-performance pure-lead agm's like Optima and Odyssey, I'm not so happy with the stepped-current charging. This is fine for standard lead-calcium agm's, but in the long run, babying a pure-lead, although it looks good on paper, is not so good for overall life.

                          However, the larger ones include a 13.6v "maintenance" or power-supply mode (careful, see the safety precautions), where one in our situation could manually give it a good float for 12 or more hours to actually finish the charge, rather than sit in a capacity reducing float-monitoring mode. QC with the newer models has been a problem for me.

                          There are a lot of good chargers out there, but one has to look very carefully, or be willing as I do for education to buy them, observe them, and keep or recycle as necessary. Kind of an expensive at-home education.

                          Optima's own chargers are actually very good with their algo. They DO charge properly up to spec, and get this - *finish* absorb before giving it a "conditioning" charge, which is properly done AFTER absorb is finished instead of jumping the gun like some other do. They will do this every 30 days if you leave it connected. That is good.

                          Considering that most people never give their agm's a proper initial extended-absorb "freshening" charge in the first place (usually 12-24 hours of say 14.4v absorb, even if no current is really flowing), then Optima's shorter, and slightly higher voltage "conditioning", after absorb is finished, is beneficial.

                          The smaller 4A model would be fine for topping off, and the larger one for deeper discharges. Either one is fine for maintenance obviously. A bit pricy, and while not made of metal like the good old days, at least the algo is correct.

                          They don't go into as fine a charging algo detail as I like in their documents, so I bought them to find out, and was VERY pleased with what I saw. Hint: with mine, I was initially frustrated at not being able to select the different battery types with a button hold. Found out that tapping your selection once the bouncing led actually illuminates upon your choice, rather than just holding it down forever, activated it perfectly every time.

                          There are many options out there if you can get hold of charger specs and actually vet them yourself. For an Optima, a no-brainer stocking stuffer would be one of their own chargers.
                          Those Optima chargers looks pretty nice. Even better then the NOCO. Definitely something to thing about. Thanks for the tip.

                          Comment


                          • #15
                            Just a quick check since I can't really tell ... hope that Blue Top of yours has a light gray case, and NOT the black case, which is the SLI version.

                            (The only real difference is in the acid/water ratio of the electrolyte)

                            The algo tells all. When it comes to agm charging, most consumer chargers are too timid, or go totally overboard. Trying to find those I like is like searching for the "Goldilocks boundary". I have no problem keeping the Optima chargers around.

                            At the very least, it makes a GREAT way for newbies doing the agm thing to make sure they start out on the right foot for eventual solar charging.

                            WARNING: I AVOID any sort of included usb-port charging that comes with a lot of stuff these days. I'm not going to take the risk of blowing out that stupid usb port, and having it take down the whole logic board of the thing I really purchased it for in the first place! Just not worth it to me. Fluff.
                            Last edited by PNjunction; 11-30-2016, 07:52 PM.

                            Comment

                            Working...
                            X