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  1. Hedges

    Finally going off grid, need a bunch of help

    My sister said she was walking her Shepherd pup above Stanford when it froze. There was a cougar on a branch above the trail, and people passing under unaware. I've never encountered one, but a few other interesting critters on my mountain property. You only need to precharge capacitors before...
  2. Hedges

    48v 400amp ANL fuse holder?

    I doubt the plastic of a fuse holder would break down at 80V vs. 48V. Difference is likely covers to keep fingers off the conductors, for safety reasons. As you say, the fuse is was matters as far as performance vs. voltage. DC breakers - and then there is polarity. If polarized, when...
  3. Hedges

    Finally going off grid, need a bunch of help

    Having a cougar sounds like a privilege. Hopefully you can learn to just give each other respectful distance. They're supposed to be intelligent, and curious about people. Not a threat at least to adults, unless defending their cubs or rabid. Even with cubs, there's video of one making sure a...
  4. Hedges

    The "Meg" Build

    If no shade on any panels, nothing jumps out at me. Even if a bypass diode was open, wouldn't matter without shade. If shorted, you'd see a lower voltage. Can you disconnect one string at a time, see if each is similar Vmp and wattage on the charge controller? We've heard that Trina panels...
  5. Hedges

    The "Meg" Build

    In the morning, SunPower is 100V out of 121Vmp. SanTan is 90V out of 150Vtypical. 83% vs. 60% is a big difference. Any shade on SanTan? Problem with bypass diodes would be an easy to understand issue. Running half of Vmp is quite low. Low light is less current, not supposed to be that much...
  6. Hedges

    License fee to use a BMS in a project

    Patent infringement is a whole different can of worms. When HP introduced a PC running Microsoft Windows, Apple sued HP for infringing on the Garbage Can or some such IP that Apple had plagiarized from Xerox Smalltalk. Microsoft stepped in and told Apple, "If you've got a problem, take it up...
  7. Hedges

    License fee to use a BMS in a project

    If I build a house to sell, can I advertise that I installed Kenmore appliances inside it? If I sell a car, can I say it has Firestone tires? If I make an alternative energy product which happens to have a transparent cover, can I take a photo of it that shows everything visible inside...
  8. Hedges

    The "Meg" Build

    Gotta wonder why. There could be some differences in light absorbed at off-angle, but wouldn't expect 5x difference. What voltage/current are the SanTan strings delivering? Could they be outside MPPT range of the charge controller? Are the SanTan partially shaded, maybe some bad bypass diodes to...
  9. Hedges

    Trying too hard

    First get the specs and types of motor loads. Those are the hardest to start. Brush-type motors should be easier, and induction motors are most difficult. If spec includes LRA (locked rotor amps), multiply by voltage to get watts and the inverter needs surge rating for several seconds at that...
  10. Hedges

    SiO2 Silicon Dioxide Batteries

    I suspect these "lead crystal" or "silicon dioxide" batteries are lead-acid gel cell. Besides the voltages, self-discharge rate, internal resistance, I also note 0.1C float charge rate, 0.2C cyclical (it's in a graph, but not listed as a parameter.) Maybe that approaches AGM rates, a bit higher...
  11. Hedges

    Battery breakthrough for electric cars

    " ... that can be charged and discharged at least 10,000 times — far more cycles than have been previously demonstrated — at a high current density. The researchers paired the new design with a commercial high energy density cathode material. This battery technology could increase the lifetime...
  12. Hedges

    all off grid is a gamble

    12V 200Ah wired 4s3p for 48V 600Ah Cycling 25% DoD would be 150 Ah, 7.5 kWh The AGM brand I use is supposed to give a bit over 2000 cycles to 25% DoD. Some brands might be half that, some FLA much longer life. You said the loss of capacity was observed a few months after lightning strike...
  13. Hedges

    which panel to choose, 18V or 36V?

    Although I have no idea what the Kanji characters mean, I'll assume that says 36Vmp, 41Voc Two panels in series would be 82Voc at 25 degrees C. In freezing weather, voltage might increase 15%, possibly 20% depending on panels specs (only found on data sheet) But it won't reach 100V, so you're...
  14. Hedges

    which panel to choose, 18V or 36V?

    Not sure what voltage your panel really is. "36V" We need the label or the data sheet; what is Vmp, what is Voc? Summer, no tilt is good. But if you want power other seasons, consider a manual tilt.
  15. Hedges

    Trying too hard

    Sunny Island has MSRP of about $5000 more or less. But a bunch are being liquidated around $2000 or so. I bought a pallet of them through eBay. They will work with new Sunny Boy or other inverters that have frequency-watts function. You're off grid, don't need latest functions required for...
  16. Hedges

    Battery breakthrough for electric cars

    Just don't get your head in the way
  17. Hedges

    Trying too hard

    Or 3 phase? "single phase 240v" Please clarify if you mean one 240V hot relative to neutral, or if you have 120/240V split phase (typical U.S.) 50 Hz or 60 Hz? I have Sunny Island, which is good for starting motors. Two Sunny Island would give you 120/240V at 11.5kW continuous, 22kW...
  18. Hedges

    Mitigation of demand from utility with solar

    Coin-op (or these days, needs to be a bill reader that only takes $20's) Current transformer + timer rigged to shut off the TV (or internet) if excessive power drawn from grid. "Negative Reinforcement" (bark collar providing appropriate feedback.)
  19. Hedges

    Design questions for a solar system

    That's the equation the paper gives to compute Imax, not fuse size. It goes on to say an additional x 1.25 to determine minimum fuse size. But with 3 or more strings, each should have a fuse. String #1 has ISC1, so should have fuse ISC1 x 1.25 x 1.25 which is ISC1 x 1.56 With fuse or breaker...
  20. Hedges

    all off grid is a gamble

    For the AGM batteries I used, last page of this manual shows 1000 cycles to 50% DoD is where capacity drops to 80% of original. http://sunxtender.com/pdfs/Sun_Xtender_Battery_Technical_Manual.pdf How deep were your cycles? Of course, by "died" you probably mean much worse than 80% capacity...
  21. Hedges

    Cinergi's 28 kWh / 4 kW Solar / 10 kW inverter RV build

    But you deleted the 1000 pound Onan down low compared to a standard unit. Overall, I think you raised the CG about 3", so don't try to drift in the turns.
  22. Hedges

    Adding storage to my Enphase system

    Somewhat different behavior with my Sunny Island, which serves as UPS (sort of) for downstream load. If power fails, Sunny Island watches power go down briefly, maybe a couple cycles (don't think there is a guaranteed response time) then disconnects from grid and supplies AC to downstream loads...
  23. Hedges

    Mitigation of demand from utility with solar

    Cooling off, it is only heat conduction and air leakage. Heating up, there are those two plus sun shining through windows and onto exterior surfaces. For either case, wind will remove air from near external walls (which had transferred some heat one way or the other) and bring in more air of...
  24. Hedges

    Grid charging and using at same time

    Many of the inverters intended for RVs have an internal transfer switch and comply with UL-<something or other> in terms of bonding neutral to ground only when shore power isn't present. Outback has had a number of inverters which do that. Some were for vehicles & RVs, some for on-grid or...
  25. Hedges

    Difference in discharge amperage

    The resistance scale of a DMM is good for larger values, like 1 ohm or 1k ohm. The values in a battery pack are more like 0.001 ohm, which can't be read that way (and you can't use the ohms scale on a circuit with power applied.) Resistance measurement is simply forcing a current and measuring...
  26. Hedges

    Grid charging and using at same time

    Some inverters have an internal transfer switch. They function like a UPS - if grid (shore power) is available, it supplies the load. When not available, battery supplies load. If inverter doesn't contain it, then can be external (or use a battery charger as Supervstech says.) More difficult is...
  27. Hedges

    Flex panel for a camper

    At 80W output and 68" x 14", that would be about 12.5% efficiency. At least it passes the smell test; CIGS is reported around 23% max for a cell. As HRTKD says, any shade and you'll get effectively nothing anyway. Determine how many hours of full sun, unshaded by trees. At a bit over $3/watt...
  28. Hedges

    Low amp 48v fuses?

    Searching for 80V and Mega, I find some fuses referred to as Mega but they look like MRBF. I do find a variety of Mega fuses, some rated 32V and some rated 58V. It seems they vary - can you determine a brand and model for the fuses you received, and look up their specs? Fuses have varying "AIC"...
  29. Hedges

    Any experts available for consulting about a home solar setup?

    Could be reasonable, or might adjust depending on usage pattern and what you want. If 42,000 Wh and 15,000W PV, 0.36C charge rate when no loads. Probably good, except it batteries approach cold or hot disconnect; max charge rate is reduced then. Keep batteries at moderate temperature and this...
  30. Hedges

    Any experts available for consulting about a home solar setup?

    Someone could do better if they happened to be local, could take a look. There are always additional parts needed depending on site condtions. If you give more details, forum members can give conflicting recommendations to help steer you in the right direction. There is SolarQueen with Alt...
  31. Hedges

    hp & watts

    There's watts and then there's VA. One subtracts current shoved back out of phase (from poor power factor) and the other is just Vrms x Arms. That could be part of the issue. Could also be load. Motors can deliver over 100% of their rating. If starting watts is really 2000W, I'd be surprised...
  32. Hedges

    Difference in discharge amperage

    That would suggest different resistance somewhere, whether bars, cells, contact to a terminal. With a heavy current being drawn, use a DMM to measure each segment, alternating between the two parallel strings. Across each busbar, across each cell, across the cables paralleling them at the ends...
  33. Hedges

    SiO2 Silicon Dioxide Batteries

    Is that related to another one discussed previously? https://diysolarforum.com/threads/silicate-salt-battery-vs-li-on.15990/post-180463 Made of lead-calcium. And completely non-toxic, you can recycle it as organic fertilizer.
  34. Hedges

    Making a Dual Axis Tracker

    Looks to me like the usual tilt of the panel has the frame covering zerk fitting. Spinning that pillow block around could make it easier to access.
  35. Hedges

    AC coupled battery supplying essential sub panel with Grid tied Micro inverter - Wiring question

    Yes, he is near retirement, so not worth buying a new fleet. Traditionally, people may start out with used equipment, buy new as they become more successful. Likely there will be a consolidation to fewer large companies performing heavy work since everything must be recent models going forward...
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