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  • #31
    Originally posted by miahallen View Post
    Chris...thanks a million for your very comprehensive response, I really appreciate it! I will do my best to follow the steps you've outlined and report back



    russ...you seem to be at odds with the sticky I linked, and with what ChrisOlson has stated in this thread:.
    That is because Chris mispoke and that is what you wanted to hear. What you think you heard is not true.
    MSEE, PE

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    • #32
      Originally posted by Sunking View Post
      Chris I was beginning to wonder and worry you took up drugs or drinking.
      Well, we been putting up wood for the winter. Got the woodshed almost full. I haven't really kept track of the cans of beer to cord ratio on splitting and rankin wood, but I think it's a positive ratio somewhere around 3 or 4 to 1
      off-grid in Northern Wisconsin for 14 years

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      • #33
        On these L16's that are so popular with off-grid folks and battery-based systems, folks should be aware that several manufacturers have been playing with high SG electrolyte and a different grid formulation to bump their ah capacity to 420. US Battery has em (the L16HC/XC or whatever they call them), and Trojan has them with the P-AC's. Interstate Battery also has them, but Interstate's L16's are made by US Battery.

        These batteries are a different animal than the Trojan "RE's" that have a lower specific gravity electrolyte. The RE's will withstand discharge to 80% SOC time after time, and they are perfectly happy. Not exceedingly efficient. But they don't stratify.

        These so-called "high capacity" L16's that these guys have come up have dense electrolyte and they are extremely sensitive to setting around and not being cycled deep enough. They were not designed for RE duty, but instead they are floor maintenance batteries used in floor sweepers and scrubbers and similar. On those floor maintenance machines they get properly cycled and are fine - and they got 50 more ah in 'em - AND they hold their voltage under load much better than the RE's. The RE batteries are a little "soft" and they tend to "sag" on voltage on discharge more.

        To date, I'm not aware that Surrette has been playing this game with their S-530's (L16 case). But for folks buying L16's be sure to pay attention to what you're getting. If it has over 380ah capacity it's more than likely one of these "high capacity" industrial batteries and they need to be treated differently than what we've been used to in the RE business. US Battery even goes as far as to recommend a 2.58VPC Absorb V for theirs. And if you don't pay attention to this they'll stratify and the bottoms of the grids will turn into solid hard sulfate in one year - at which point they are junk. And the manufactures of them have no mercy on warranty claims either. If you sulfate one they'll just say, "well you didn't charge it right" (which is actually true) and you're stuck with buying a new one.
        off-grid in Northern Wisconsin for 14 years

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        • #34
          Originally posted by ChrisOlson View Post
          On these L16's that are so popular with off-grid folks and battery-based systems, folks should be aware that several manufacturers have been playing with high SG electrolyte and a different grid formulation to bump their ah capacity to 420. US Battery has em (the L16HC/XC or whatever they call them), and Trojan has them with the P-AC's. Interstate Battery also has them, but Interstate's L16's are made by US Battery.

          These batteries are a different animal than the Trojan "RE's" that have a lower specific gravity electrolyte. The RE's will withstand discharge to 80% SOC time after time, and they are perfectly happy. Not exceedingly efficient. But they don't stratify.

          These so-called "high capacity" L16's that these guys have come up have dense electrolyte and they are extremely sensitive to setting around and not being cycled deep enough. They were not designed for RE duty, but instead they are floor maintenance batteries used in floor sweepers and scrubbers and similar. On those floor maintenance machines they get properly cycled and are fine - and they got 50 more ah in 'em - AND they hold their voltage under load much better than the RE's. The RE batteries are a little "soft" and they tend to "sag" on voltage on discharge more.

          To date, I'm not aware that Surrette has been playing this game with their S-530's (L16 case). But for folks buying L16's be sure to pay attention to what you're getting. If it has over 380ah capacity it's more than likely one of these "high capacity" industrial batteries and they need to be treated differently than what we've been used to in the RE business. US Battery even goes as far as to recommend a 2.58VPC Absorb V for theirs. And if you don't pay attention to this they'll stratify and the bottoms of the grids will turn into solid hard sulfate in one year - at which point they are junk. And the manufactures of them have no mercy on warranty claims either. If you sulfate one they'll just say, "well you didn't charge it right" (which is actually true) and you're stuck with buying a new one.
          Agree with everything.
          MSEE, PE

          Comment


          • #35
            Originally posted by Sunking View Post
            Agree with everything.
            I'm not saying these high capacity L16's are necessarily bad either. I rather like them. They made them because the floor maintenance business wanted higher capacity batteries for their machines. The Surrette S-530 has always been 400-428ah, but they didn't go with high SG electrolyte to do it. But that's why a Surrette S-530 weighs more than a Trojan. Not sure who's right - the Surrette S-530's are proven and expensive. The new L16HC's from the other guys are pretty new and much cheaper.
            off-grid in Northern Wisconsin for 14 years

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            • #36
              Originally posted by ChrisOlson View Post
              The new L16HC's from the other guys are pretty new and much cheaper.
              Who is other guy? USB?

              Don't think Trojan makes that model.
              MSEE, PE

              Comment


              • #37
                Originally posted by ChrisOlson View Post
                I'm not saying these high capacity L16's are necessarily bad either. I rather like them. They made them because the floor maintenance business wanted higher capacity batteries for their machines. The Surrette S-530 has always been 400-428ah, but they didn't go with high SG electrolyte to do it. But that's why a Surrette S-530 weighs more than a Trojan. Not sure who's right - the Surrette S-530's are proven and expensive. The new L16HC's from the other guys are pretty new and much cheaper.
                They do it now too, The S-550 is weigh less and have more capacity than the S-530.

                Comment


                • #38
                  Originally posted by ChrisOlson View Post
                  Those Trojan's can be discharged to 80% DoD, absolutely no problem. 50% DoD is normal with them for off-grid systems to achieve a balance of best efficiency vs kWh stored over their life. The more shallow you discharge them, the more cycles you get. But their efficiency drops and you get LESS kWh stored over their useful life vs input energy. They are a 6-7 year battery on 50% DoD cycling duty.

                  The problem here is understanding the system, and the settings. Trojan keeps constantly fiddling with SG in their batteries, but the P-AC's are their latest high-capacity L16's with 1.280 electrolyte. Proper absorb voltage is 2.47VPC (59.2V on a 48V system). EQ voltage should be set to 2.58VPC and Float is 2.20VPC.

                  Step #1 - verify that all your charge controllers are set to those values for each charge stage.

                  Step #2 - verify that the inverter/charger is set to those values for each charge stage.

                  Now, you need to charge your batteries. That means absorbing them at 59.2V until you get a SG reading of 1.275-1.285 on every cell. Ignore the timers in the FM80's and keep absorbing them until you get that SG. At this time, assuming you have a FNDC, it should show around 8.4 amps going to the batteries at 59.2V.

                  Congratulations - your batteries are now at 100% SOC.

                  Now you need to refer to the manual for the FNDC and sync it. And also verify that you have the ah capacity set to 420, discharge rate at 20, discharge floor at 50, Peukert Number at 1.25, and the auto sync setting to 9 @ 59V. There's a whole bunch of other settings in it too, that should be gone over and verified that they're correct. Since the FP-1 is all factory wired, we'll assume the shunt is not wired backwards. But with Outback's quality control as of late, anything is possible. The next few hours will tell.

                  Now watch your system under load. The Mate3 should be showing SOC at 100% initially, then drop gradually as the battery discharges. It should show net amps being used from the battery. If it shows net amps going INTO the battery with no incoming power from FM80, then the shunt is backwards. Contact Outback Tech Support and tell them your FP-1 is f&*ked up and you want somebody on the phone that can tell you how to fix it. Mary Raub no longer works in Outback Tech Support and she was the last one that I knew that actually knew what was going on there. So good luck with that.

                  Take note of amp-hours used from the battery as it discharges. When it shows 100ah used, the SOC should show 76% +/- Peukert compensation, which will be very small for loads less than 1,000-1,100 watts. If you don't get those numbers then something is wrong and you need to contact Outback Tech Support and tell them it don't work.

                  I'm more a Schneider Electric guy and I only work with Outback systems when other off-grid folks I know can't figure them out. I usually can't figure them out either and end up having to control a strong urge to smash the Mate3 with a 16oz ball peen hammer. But getting the bank to verified 100% SOC and syncing the FNDC SHOULD "fix" it.
                  OK Chris. I've finally gotten around to following your instructions and the batteries seem to be just fine. The inverter & charge controller have bother been operating perfectly normal for the past couple weeks, and I have not had anymore mysterious power outages. However, the FNDC meter & MATE 3 indicators are still not playing nicely. The MATE 3 sees the battery voltage correctly, but there is definitely a disconnect between the FNDC & MATE 3. As it is right now, the MATE 3 never indicates the PV energy being used to charge the batteries (even the the charge controller is operating normally). It just constantly shows the batteries discharging right down to SoC...throws a bunch of errors and faults, and then after reaching 0, it resets and indicates 100% charge again, as if everything is normal. The 5 LED indicator the the FNDC mimics the same behavior as if completely ignoring the battery voltage levels and the CC cycling through MPPT, Absorb, & Float as it should.

                  I'm not sure if I successfully sync'd the FNDC as you suggested...but I'm thinking that might be the real issue here.

                  P1060959.JPG

                  P1060960.JPG

                  So, I'm confident my batteries were not damaged at this point. But I'm not sure why the system is ignoring the CC's operation. I also cannot properly account for the power outages that I experienced a couple weeks ago.

                  Originally posted by Sunking View Post
                  That is because Chris mispoke and that is what you wanted to hear. What you think you heard is not true.
                  I have reread this thread 4 or 5 times now, and it seems to me you're out of line Sunking. I am trying with all my facilities to wrap my head around this stuff...I've spent my life savings on this move and my new life here, a large portion of that on this electrical system. I am trying to be as diligent as I can in learning what I need to know to be successful, and I was not reading just what I wanted to hear. If Chris misspoke, then he misspoke...but I didn't read what I wanted to read, I read what he wrote.

                  As far as this part of the question goes, I'm still a bit confused because after you made these accusations toward me, Chris wrote back with this:

                  Originally posted by ChrisOlson View Post
                  These batteries are a different animal than the Trojan "RE's" that have a lower specific gravity electrolyte. The RE's will withstand discharge to 80% SOC time after time, and they are perfectly happy. Not exceedingly efficient. But they don't stratify.

                  These so-called "high capacity" L16's that these guys have come up have dense electrolyte and they are extremely sensitive to setting around and not being cycled deep enough. They were not designed for RE duty, but instead they are floor maintenance batteries used in floor sweepers and scrubbers and similar. On those floor maintenance machines they get properly cycled and are fine - and they got 50 more ah in 'em - AND they hold their voltage under load much better than the RE's. The RE batteries are a little "soft" and they tend to "sag" on voltage on discharge more.
                  Then you said:

                  Originally posted by Sunking
                  Agree with everything.
                  ...which seems to me the complete opposite of what you were saying earlier. Now, I'm not trying to read into...or read what I want...I'm still trying to understand. When Chris says, "These so-called "high capacity" L16's that these guys have come up have dense electrolyte and they are extremely sensitive to setting around and not being cycled deep enough." To my mind, that seems to indicate only discharging them to 80% SoC on a regular basis is NOT good for these batteries (opposite of what you said earlier). Being "deep cycled" translates to what? 50% DoD? 80% DoD?

                  @ChrisOlson - Outback's OPTICSre "cloud" server...no, I don't trust cloud platforms either (I'm an IA guy by trade)
                  3680W - FLEXmax 80 - FX3048T - 8x L16P-AC 435Ah

                  Comment


                  • #39
                    miahallen, I'm afraid your problem with your FNDC and/or charge controllers not talking to the Mate3 is a problem that needs to be run past Outback tech support. I assume you have the equipment plugged into your hub, as is normal, and at that point it should "just work". I think the stuff is working standaone but not communicating on the hub network with the Mate3 for some reason. And I can't think of anything obvious off the top of my head (other than not being plugged into the hub) that would cause that.

                    You can pull your batteries down to 80% DoD (20% SOC), but that's usually not practical on an inverter system because the voltage will get so low under load that the inverter will probably shut off. I'd say somewhere in the 35-40% SOC range is practical, as under normal loads here that's about as low as we can go and keep things lit. If we're gone and the loads on our system are very, very light (discharging at less than the 100hr rate) then the batteries can be successfully discharged lower. But if you "work" them down to, or below, 50% SOC once in awhile they'll be happy. You'll notice that after a deeper discharge and a full recharge that they seem to have renewed life and don't hardly voltage sag at all on subsequent discharge cycles. The deeper discharge exposing new active plate material and the electrolyte getting thoroughly stirred upon recharge (you'll notice it takes more time in absorb after a deep discharge too) helps keep them healthy.

                    Definitely do NOT cycle those batteries to only 80% SOC and never any deeper than that. They won't like you very well and after a year you'll wonder why your batteries have seemed to have lost all their capacity. Those are not fragile golf cart batteries.
                    off-grid in Northern Wisconsin for 14 years

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