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  • #46
    Originally posted by paulcheung View Post
    This is the one I have.

    OTC 4619 Professional Battery Hydrometer
    Well, I didn't know that Owatonna Tool Co was building battery hydrometers. And turns out I was right. That's one of those Chinese ones with the paper scale inside the float tube that you have to watch in case the paper slips. OTC (been a manufacturer of specialty service tools for OEM's since 1934, based in Owatonna, Minnesota and now owned by Sealed Power in Muskegon, Michigan) buys and resells that hydrometer from the same Chinese supplier that makes them for everybody else.
    off-grid in Northern Wisconsin for 14 years

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    • #47
      I do it a bit differently than Chris does, I load the snot out of the genset (95%), and what it's not feeding into loads, it's changing the battery with. When the toaster comes on, the charger throttles back, and if the big 240V pump comes, on the battery flow on the Conext combox diagram, switches from charge to discharge, and the batteries are aiding the genset while the peak load is on. And when the load reduces, the batteries are back to charging. Very fancy (and fast) sensors in the XW that it can track these events and not disqualify a lugged down genset.
      Learned a new one yesterday. Cloudy, drizzle & rain. I'd fired up the diesel, and was running loads and charging batteries, and the sun came out of a break in the clouds and slammed the PV arrays. 5 additional KW hit the batteries, and the generator unloaded. I heard the change in sound and thought Uh Oh - what happened? Got to the generator shed, and read the meters, since the XW thought the batteries were full, it stopped charging and the generator was loafing along with only about 100w of load. So it was all cooled down and ready to shut off by the time I figured it all out.
      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

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      • #48
        Originally posted by Mike90250 View Post
        I'd fired up the diesel, and was running loads and charging batteries, and the sun came out of a break in the clouds and slammed the PV arrays. 5 additional KW hit the batteries, and the generator unloaded.
        There must have been some huge peak currents into the batteries. When I have this problem (sun comes out while generator is running) I can hit bulk charging currents of almost C/4 (not desirable). My system is DC coupled... no regulation of current until absorb voltage is achieved.

        --mapmaker
        ob 3524, FM60, ePanel, 4 L16, 4 x 235 watt panels

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        • #49
          Originally posted by Mike90250 View Post
          Learned a new one yesterday. Cloudy, drizzle & rain. I'd fired up the diesel, and was running loads and charging batteries, and the sun came out of a break in the clouds and slammed the PV arrays. 5 additional KW hit the batteries, and the generator unloaded.
          I've seen 'em do that before. If your charger settings in the XW are correct, it gives priority to the MPPT's for charging. The nice thing is that if you have AGS it automatically shuts the generator down when that happens (assuming it was automatically started due to shortage of incoming RE).
          off-grid in Northern Wisconsin for 14 years

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          • #50
            Solar System not Working

            HI All this is my first thread, I am not sure if I should be posting here as I could not find a way of posting back in the main screen.
            I have read and tried educating myself over the past 12 months, but unfortunately I have a problem, that is just not clear to me, so if you could help that would be great, thank you in antisapation.

            the system
            8 x 110amp deep cycle batteries wired in 24 volt configuration
            5 205 watt solar panels wired neutral to natural and positive to positive back to the inverter
            1 50Amp mppt controller

            all I am trying to run is a 150wat inverter which in turn is running a chicken brooder which is 75 watt

            I was running a 1kg inverter back in peak summer, but found the batteries were going flat so that is why I changed to the 150 watt inverter.
            I live in Southern England and we have had really good sun for quite some time.

            the problem is the batteries get up to 26.4 volts in the day, but in the morning it is down to 23.6 volts,

            I can't understand why the batteries and panels are not coping with such a low draw of power!

            an any one please help

            best wishes Derek

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            • #51
              Originally posted by Alpaca-Meadow View Post
              HI All this is my first thread, I am not sure if I should be posting here as I could not find a way of posting back in the main screen.
              Welcome to the forum Derek,

              Hopefully the moderators will move this to its own thread.

              I'm guessing that your batteries are 12 volt batteries. It that is correct you have 440 ah at 24 volts and the batteries are in 4 parallel strings of 2 batteries (in series) per string.

              Therefore you have 10,560 watthours of storage and you should try not to use more than 2500 of them before recharging.

              Your brooder is 75 watts. I will guess that between the end of one charging day and the beginning of the next day is about 18 hours. 18 hours X 75 watts = 1350 watthours. Of course your inverter is not 100% efficient, so figure you need to draw 1500 watthours overnight.

              During the day, your array will typically provide about 25 amps of charge current to your batteries. That's a bit on the low side, considering the panels must charge the batteries while still powering the load.

              Chances are you are doing a slow deficit charge. It takes a long time to get a battery up to 100.0% SOC (state of charge). If you only get to 99.9% every day, the 99.9% becomes your new 100% because of sulfation. After awhile you have 99.9% of 99.9% of 99.9%, etc.

              I think there are some other issues with your system. The most serious is that (I think) you have 4 parallel strings of batteries. That is a formula for disaster... the batteries do not charge evenly because the current to the 4 strings does not divide evenly.. As the battery strings diverge, you have one string doing all the work while the others die of sulfation. The hard working string(s) die sooner from overwork, and because you daily load is being powered by a smaller battery which then gets over discharged.

              Also, what type of batteries are these? They may not be suited for deep cycle service.

              --mapmaker
              ob 3524, FM60, ePanel, 4 L16, 4 x 235 watt panels

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              • #52
                batteries

                HI Mapmaker and thank you for your time and answer, it took me ages to find the reply! lol
                anyway am here now,
                the batteries are 12 volt caravan batteries all brought new and at the same time, the ones with the green lights on them to show charge.
                they are wired series / parallel combination bringing the voltage up to 24 volts
                does this throw a different light on it (excuse the pun)

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                • #53
                  What is the spec of these panels? I suspect the voltage may be too low to properly charge these batteries at 24 volts wired in parallels, how far is the panels to the charge controller?

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                  • #54
                    solar panels

                    HI The panels I purchased are Ideal Thermasol TSPV 205 PE – Solar PV Collectors 205W

                    they are wired negative to negative and positive to positive the furthest panel is about 12 meters away from batteries and they are all joined together so the last panel is only 7 meters away from battery.

                    not sure of the spec but will look on back of one of the panels

                    regards Derek

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                    • #55
                      Yeap, These panels are 26.52 volts Vmp, Can't charge the 24 volts battery bank wired in parallel, You either have to wire in 2 in series with 2 parallel totals four or get one more panels wire 2 or 3 in series to charge your battery bank properly depend on the charge controller.

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                      • #56
                        Originally posted by paulcheung View Post
                        What is the spec of these panels? I suspect the voltage may be too low to properly charge these batteries at 24 volts wired in parallels, how far is the panels to the charge controller?
                        Good catch on those panels, Paul. I saw he had 5 panels and an MPPT controller and just assumed....

                        --mapmaker
                        ob 3524, FM60, ePanel, 4 L16, 4 x 235 watt panels

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                        • #57
                          batteries

                          battery2.jpg
                          this is how I have wired the batteries x 8 of course
                          the controller is EPsolar 40A Tracer4210RN MPPT Solar Battery Charge Controller

                          Its been a while since my days of wiring please remind me parallel and series
                          thanks you all for you help, the chickens will be most grateful

                          Derek

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                          • #58
                            Originally posted by Alpaca-Meadow View Post
                            this is how I have wired the batteries x 8 of course
                            That wiring is a disaster. Look at the diagrams on Smartgauge.
                            http://www.smartgauge.co.uk/batt_con.html

                            One problem with the smartgauge site is they show you how to do parallel batteries, but they don't tell you how bad an idea it is to have parallel batteries at all.

                            --mapmaker
                            ob 3524, FM60, ePanel, 4 L16, 4 x 235 watt panels

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                            • #59
                              wiring batteries

                              Thank you Mapmaker.
                              I see that smart gauge site is showing 12 volt wiring.
                              the reason I wired the batteries as I did in 24 volts was because of the mppt controller only being 40amps
                              is there a site / image you can direct me to, to show me the correct way of wiring them please?

                              Thanks again for your kind response

                              Derek

                              Comment


                              • #60
                                Your immediate problem is not the battery wiring. it is the panels wiring. you can't wiring 5 panels positive to positive, negative to negative to get high enough voltage to charge the batteries at 24 volts, you need at least 30 to 35 volts to charge the batteries properly. That charge controller only accept 100 volts DC input if I am not mistaken. You need to wire your panels 2 in a series and parallel the 2 series together. that you leave on for spare or you get one more.

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