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Weasel

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Weasel last won the day on January 11

Weasel had the most liked content!

About Weasel

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  • Birthday 11/03/1983

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  1. Weasel

    8 X 6V 245Ah US145XC2 batteries

    i see, was going to suggest you stick to to them and not mix. ill send you a PM with my details.
  2. Weasel

    8 X 6V 245Ah US145XC2 batteries

    can do, im in rooihuiskraal north. but are you looking to expand or replace your bank?
  3. Weasel

    8 X 6V 245Ah US145XC2 batteries

    They are yes
  4. oh yes its not happy that one... @MB1 looks like the best thing you have there is the 75/15. i still think somethings up with that panel :/
  5. pmax should have gone over 100W, its in open air as well.. with some cloud edge over 200W would not be surprising. How long is the panels cable and what thickness of wire. yes load isnt more than what that panel should generate, i agree somethings up.
  6. That is more of a weather restriction there. previous day was in bulk the whole time, i.e battery isn't full. if there was a spat of sunshine on the panel Pmax should have at least gone over 100W.. something else going on here. how bad is the weather really?
  7. Weasel

    Grid Tied Inverter

    You can get the solic 300 in SA.. im using that too. prevents export by pushing into the geyser.
  8. Weasel

    Grid Tied Inverter

    Have to say the Solis is great quality, ive said it on the forum before, nippon caps panasonic relays. software isnt all that great but for quick ROI its the one to go for. built in grid limiter, too.
  9. Weasel

    Battery Spikes

    Shall take no part in that . i think you can appreciate how difficult it is to accurately compare. The 100/50 has 2 inductors, i did a repair on one (failed RMA, and yes i it looks terrible now) but i wasn't aware they where driven that way, ill be sure to check it out, learn something new every day. To test of the victrons ive got pretty much what you have 150/35, 100/50, 75/15, 100/20s, sorry this scope is staying put for now . I unfortunately also have the same free time issue. been building a linear supply for 80V 5A to simulate panels but the heat dissipation is a nightmare, its been shelved for months.
  10. Weasel

    Battery Spikes

    That will be tricky, it depends on so much. it would need to be a 60A mppt, they are pretty spensive. same battery bank at roughly same state of charge. same input power, i don't have a 150V bench supply (yet anyway) but the list goes on. Then, what about the differences, what exactly would we make of it i'm sure results wouldn't be bad anyway, its also worth mentioning the the draw from an inverter is much more shocking, like i'm talking even that 375 of yours, whats it really doing what i find interesting is how much of a difference a cap bank will make and if it will prolong life of batteries and consumers attached to the bank etc... or wait let me rather say how much would be enough to make an arguable difference..
  11. Weasel

    Battery Spikes

    There you @The Terrible Triplett this is a 150/35 at the same kind of charge current. There is some ringing but current seems to be mostly in the positive and 10 times less. battery voltage is showing that its not really affected, 400mv swing. This looks like a whole can of worms topic, so what do you guys think, can these high current transients like in the first one cause damage to batteries. lets keep in mind its a chemical process and a millisecond may mean nothing.
  12. Weasel

    Battery Spikes

    So i was chatting to someone the other day that was convinced that PWM regulator killed his batteries, reason given was the spikes that gone into the bank directly from the panels. So yes, we know how PWM works and really it shouldn't be a problem unless your array and or bank is not appropriately sized, i mean the charge voltage has to be higher but how much is too much? i've always thought it would be good for the batteries to some extent, preventing sulfation and as long as there's no heat buildup or some internal arching i cant see a high voltage being an issue. He was complaining of spikes in the order of 20 volts. My thoughts at the time where that it will reach that level if your batteries are on the way out, basically they're not absorbing the power because of high IR, also using 72 cell panels for 12V with pwm isn't helping you in any way, you'll get more power with 2 100W panels in parallel but i lost him there. So ill usually tell someone if you are unsure, or you want flexibility just pony up and get an mppt, and its exactly what ended up suggesting. But the whole chat got me thinking. An mppt will also have "spiking" and we know it will be less than a pre-set panel voltage by the nature of the conversion which means it will be "safer"; its spiking should also give some indication to the state of your batteries, basically its applying enough voltage for the available current to move while also tracking the maximum power point from the panel. Now to finally get to the point of the post, out of curiosity on the above i was testing a crappy MPPT and got the below plots. So what you are looking at here is a charged up very new AGM GEL battery in absorption. nothing else is connected just mppt, no loads. voltages are directly on the terminals of the battery. Its busy charging at around 5A but the switching on the converter is drawing back current as well. kind of like a 10 step forward 7 step back thing going on here. its clearly ringing on the inductor, but the currents proportional to the charge rate blew my mind. i'm thinking this is thing is a battery killer, im fine with the forward transients but what about the draw? and the p-p voltages on the terminals is almost 7v for a charged battery... moral of the story i think is get a good mppt, I i have a few lined up i want to test when i get time then the rant can continue.
  13. Weasel

    5kva Axpert MKS model - faulty

    Rule no1 if it aint broke.
  14. Have had these in my garage, for the last 2 years and realized i wont be using them anytime soon. i've charged them often kept water levels etc. Their a bit filthy because they have some terminal leakage but i recon they are in very good condition. i'm willing to do a full capacity test for anyone interested and was thinking 1.2k per battery.
  15. Weasel

    ROYAL Big Bang

    IMO overcharge either due to temps or settings, you say it was in standby use and should therefore not really get cycle charges. each day a cycle charge applied causing electrolyte to vent off, cells dry out and cause sediment at the bottom of the plates, eventually it all shorts out at causes a rapid heating. Royal granted isnt the best bat but check that you didn't set it incorrectly, i would set float to 13.6 with a -15 to -20 mv per degree C derating and in such standby condition i would limit absorption time to say 2 or 3 hours knowing that it should technically be full most of the time. bulk and absorb id set lower than recommended, more to the standard 14.4 again knowing that it will remain in standby. lastly id put the 75/15 very close to the battery so the temps can be "measured". if temps in there where say 40c 13.6 should be de-rated to 13.3-13.4 to prevent venting, hope this all makes sense.
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