diy solar

diy solar

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    Amperage question

    Neglecting losses & such, I get 48vdc x 60Adc = 2880w into the batts. 30A x 240vac = 7200W. Your gen is then loaded to 2880w/7200w = 0.4 = 40% of capacity, so 0.4 x 30A = 12A AC.
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    can you build a system based on yearly use number ?

    2000 kwh/yr x yr/8760 hrs. The yrs & the hrs cancel out & you get 2000/8760 kw = 228 w continuously. Our house takes 1 kw continuously [the US average] & houses in the NE take 4x this.
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    2 Victron Orion 30a dc to dc & alternator issue not enough amps

    The voltage regulator controls the alt. output by varying the voltage to the field coil, assuming a high enough RPM [1500 or so]. I'd look there to see why you're not getting rated output.
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    Headaches with Daly BMS.

    Your system is oscillating, an "undamped" oscillation. It whacks into the high limit voltage & then the low limit voltage, acting like a "bang-bang" control system.–bang_control Better is a proportional control system. Maybe the BMS needs a minimum battery...
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    We get many telemarketing calls each day

    Lately when they call, I ask them if "they got the letter". Them: What letter? Me: the government is prosecuting you & your company for wire fraud. I'm surprised you're not in prison right now, you & your boss.
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    Dc rated switches

    The hair dryer pulls 10A or so & allows you to measure contact resistance in the milliohm range. >>>>contact resistance of 3 milliohms >>>>10A ......^.......................................................^ ...............voltmeter reads 30 mV. The DVM prods should not touch the leads that pass...
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    Aims Power 12v 3000 watt inverter/charger maximum amp draw

    Fuses I've seen can hold between at 100% & 115% of rated capacity, "forever." You have to see the "clearing time" curve. It's usually plotted on log-log paper. see page 9.
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    Titan Solar Generator 1.5 year update and review

    If a company doesn't honor a warranty, pretty soon everybody knows about it & so they're pressured to honor the warranty. But some companies choose to sue anyone who badmouths them, regardless of the truth.
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    Docan Power EVE 304AH LiPO 2nd batch No bueno

    It should. 70% good shipments gives you 50-50 random chance of having both good. With 3 shipments your chance is 1/3 all good. To get the base rate of good shipments we need to hear from many others as to what percent of shipments were bad, out of how many shipments. Of course, if you notify...
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    48V Server Battery Questions

    If you get the programming wrong, I guess the worst is, it doesn't work. I'd hope these intelligent devices protect themselves from operator error & bad configurations but there is always a "Black Swan event". And they can't be reduced to some simple equivalent circuit using a voltage source...
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    Need help with a hybrid configuration at my workshop. Pretty confused.

    A panel not running at the open circuit voltage while in light looks like a current source. If one panel can deliver 10A & the other, 5A, & you put them in series you should only get 5A. I guess it's like a 10A fuse in series with a 5A fuse. . .the combo clears at 5A.
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    Where to place less capacity cells in the battery?

    For a series pack it should make no difference, all the cells will be drained at the same amps.
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    Need help with a hybrid configuration at my workshop. Pretty confused.

    If your panel is mounted at a 45 deg angle, you'll get 71% of full sun [100 x cosine of 45 = 0.707]. If at 30, 86.6% of full sun. Shade may count as 16% of full sun & the angle may not matter.
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    Epever charge controller low voltage disconnect at 11.1V???

    On the 200v scale it would read 199.0v full scale, so your reading was 78.0? MM300 accuracy is 0.8% of 200v + 3 digits. 0.8% of 200v = 1.6v so a true voltage of 78.00000 could read 78.0 + 1.6 + 0.3 = 79.9v If your Epever has the same specs, a true voltage of 82.00000 could read 82 - 1.6 - 0.3...
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    Voltage Difference

    Losing 0.4v at reasonable current levels seems like a corroded connection, so trace down what connection is doing this. It's unlikely that four connections are losing 0.1v each.
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    Voltage of a Full 80% Capacity LiPo4 battery

    With the same charging current, you will input 8kwh of energy in 80% of the time that it would take to input 10kwh of capacity. I'd think same end voltage.
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    Epever charge controller low voltage disconnect at 11.1V???

    IIRC 11v = zero SOC. Epever must have something in mind. The readings are within 3% of 80v, that's kind of a wide tolerance for today's meters. Check the multimeter for reading 1.56v on a new flashlight battery but it could still be off on the higher scales. What's the make & model of your meter?
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    Ground Fault Indicator Troubleshooting (F150 2kw <--> Ecoflow River pro)

    If the config is truck power [60 Hz sine wave] => GFCI => Ecoflow and the Ecoflow has capacitance to ground of more than 80 nanofarads, then 4 mA will flow to ground & probably trip the GFCI. If the truck power is some kind of modified sine wave, then IDK & so run some tests to get more clues.
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    Is it ok to use tape?

    "Swollen LiFePO4 batteries are the result of too much current inside a cell of the battery, which causes a build-up of heat and gas. This can be caused by overcharging, deep discharge, overheating to battery or manufacturer defects, or environmental reasons." Today I have learned something.
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    connecting an inverter: spark prevention / reduction

    It's an inrush of current to charge the capacitor. Your battery's internal impedance probably limits this current so you then have an RC ckt. V ---R----| ...............C ................| ............ground With an ideal battery instantly connected to a capacitor, the current would be...
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    Rough draft

    No comprende, señor.
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    Maximizing space for solar array on shed

    Roof mount with no permit? Can't sell house even if you say "as is"? Don't tell your house insurer. I can't imagine how many NEC violations my house has. If I have to sell I will just disconnect all my mods. If we die first then my kids will have to deal with selling. Our insurer wrote us a...
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    Renogy DCC50S input connection

    Solar =>...............................|renogy| veh. batt + series relay <=> |renogy| => load + storage batt. I'd have a SPST relay with 80A contacts that auto opens if the veh. batt. voltage drops too low. A voltage comparator drives the relay coil. The comparator ckt operates from a 5v...
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    Inverter size for log splitter

    I don't see why. Try loading it with a hair dryer, 1200w, a resistive load w/no surge. Also try elec. drills, drill presses, table saws & vacuum cleaners. The splitter motor may have a commutator, which sparks. If the inverter has a built in GFCI or AFCI, :(
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    Inverter size for log splitter

    7 tons & 2 HP will take 13 sec. to split a 1' long log, assuming no losses in the splitter pump. If you have more time you can go with less than 7 tons but I guess that ship has sailed. The speed is probably constant, log or no log. The load profile is idling power, then 1500w for 13 sec...
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    Questions on wire/fuse between batteries and inverter

    For some high inrush currents a slo-blo fuse is recommended. Some HVAC equipment without the "soft-start" option asks for special panel breakers. The trick for any fuse/breaker is to let thru the high but normal inrush current but still decide if the current is excessive for too many...
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    Going to start a RV solar project next summer.

    Can you summarize what to do & what not to do & what may work? Greetings, Mr. 59: How many days of cloud cover? Can you chase the sun if necessary? Toto, I think I am not in Kansas anymore. :giggle:
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    Solar & Wind Combiner

    Price out a 60A [If, forward current, spec.] diode/rectifier than can withstand 30v (PIV or PRF, peak reverse voltage) for a 12v system or 100v PIV or PRV for a 48v system or 200v for a 96v system. It'll be dissipating 60w & it may be as big as a marshmallow & require a heat sink.
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    Battery pack seemingly getting out of balance

    Here’s how I would tackle the problem of deciding whether my costly batteries are being damaged. Assuming both your meter & your BMS are working properly, my spreadsheet tells me that the average voltage of all 16 readings is 3.319v. What does your BMS flag as an abnormally low voltage & an...
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    Battery pack seemingly getting out of balance

    3.360v BMS and 3.350v BMS The average is 3.355v So readings are within +/- 0.14% of each other. This is probably within spec. What is a typical accuracy spec for a DMM on the 10v or 20v scale [you can't use the 2v scale]? But. . . I have to say interpreting accuracy specs is not easy. For...
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    Resistive heater

    100 BTUs/hr but don't touch the surface.
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    Battery pack seemingly getting out of balance

    Meter out of whack or BMS out of whack or both out of whack. A BMS is more complex than a meter so I'd say the BMS is at fault. It's relatively easy to check the meter. A working car battery not being charged or discharged should read about 12.8vdc.
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    Jack Rickard said the BMS started most the fires in the early days. Balance resistors heat. This Pack went up today and IDK why.

    There's supposed to be internal circuitry protection against this worst case scenario. It takes a lot of watts to do that much damage & the batteries may now have internal damage from overcorrect. This will give you idea of the temps.
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    Camp lighting

    I'm assuming you lose 50% in battery heating. Maybe not. For a 10' x 10' camp area & 10 lux, you want a total of 200 lumens. Work backward to how many LED fixtures at how much power.
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    Giandel Earthing and N-E bonding

    Current or voltage in excess of spec'ed values for the equipment will eventually cause a failure.