It does seem that 60-70°F is about the best temperature for batteries in use, but things don't really get terrible until the heat gets around 100°F. In hot environments, its important to keep them out of extreme temps such as a metal box in the sun, but I don't think you'd see terrible results...
Good suggestion.
But if threads start staying on topic around here, I will begin to wonder if the people I've been chatting with have been replaced by bots.
:unsure:
As @zanydroid said above, I could directly drain the water from the dryer. It wasn't convenient to drain it by gravity until I could stack the dryer on the washer, and I didn't want a hose running across the floor to the floor drain so I left it configured to catch the water in the compartment...
Here's the numbers I find interesting.
I ampere of current is 1 coulomb of electrons passing by in one second.
1 coulomb = 6.2415090744×10¹⁸ or written without scientific notation, 6241509074400000000 electrons
so 1 A of current is 6241509074400000000 electrons per second
Sounds like a lot of...
Below is a portion of the datasheet for your panel from http://support.newpowa.com/support/solutions/articles/63000148028-npa175s-12h
It is more complete than the label on the panel.
The output of the panel changes with temperature, so the calculator needs to know the temperature coefficient...
I believe @Reigate is referring to the wire lugs being able to rotate to a position where they would touch the aluminum backing plate on the BMS. I had a similar concern, but it appeared that the copper connection sits just higher than the aluminum plate, with the exception of two screws in the...
You can't get a valid resistance measurement on an energized circuit.
Your ohm meter works by supplying a small amount of current and then measuring the voltage drop that it creates. If you try to measure an energized circuit with an ohm meter, it is going to see the voltage drop from the...
They have the voltage temperature coefficient listed in mv/°C on your panel, and the calculator wants it in %/°C. If you click the little calculator icon by that blank in the calculator, it will pop up a conversion tool. Just don't forget to enter the minus sign.
Otherwise it converts to...
It looks like you've put a lot of thought into your build.
One suggestion I would give is that it is only your batteries that need to be warmed. Warming the entire compartment is not as efficient as putting the heading pads in contact with the bottom of the cells so that the heat can conduct...
So the difference between the way NMC and LiFePO4 burn relates to the source of the oxygen. Both have a flammable electrolyte.
In the video @HighTechLab made, he points out that you can see the cell material glowing red hot inside the battery. Definitely hot enough to ignite flammable...
@fhorst , this is an interesting problem. I don't have a new answer to suggest, but just some things to think about.
To feel a shock from DC power, electric current has to flow through your body. You have to have completed a circuit. If you touch something at 40V but have no connection...
I've been wondering about how much benefit the Tigo optimizers have ever since I read this blog post: https://www.mcelectrical.com.au/tigo-optimiser-recall/
However, it sounds like the problem with poor performance or even negative impacts to performance existed for people who wanted to only...
If you are interested in studies, I ran across this one that was published in 2015.
Degradation Predictions of Lithium Iron Phosphate Battery
The first graph shows their assessment of capacity loss over time at 90% state of charge an at different temperatures.
Then they showed another graph...
This is a circuit breaker, which is rated to open when the current exceeds 100 amps.
I think the voltage ratings may be what is confusing you. This breaker is rated for 240v AC and only 60v DC. Some breakers are not rated for use with DC current at all. The ones that are rated for DC always...
Steve, I read through the EVE LF280 Spec Sheet that you posted on Thursday, and there is one part of it where I just don't understand what they are talking about. In the table portion, they have this information on cycle life:
I think there is a misprint, and one is supposed to be (Without...
I'm sorry if I'm confusing the issue. What you are proposing to do does meet the safety requirements according to the 2017 code with the ground fault things met and a disconnecting means as is in the diagram.
The old fusing requirements from the 2014 code were to protect systems that had...
This is a question that can probably only be answered by your local authority having jurisdiction (AHJ) at your permits and inspections office.
US National Electric Code prior to 2014 required shutdown within 10 feet of the array outside the building. From 2017 on, it requires shutdown within...
Yeah, it is important to get this correct. I've seen a couple examples on youtube where people have had their solar charge controllers refuse to turn on in the winter until the sun had warmed the panels up. Worst case scenario is that the charge controller gets destroyed.
This probably should also be a thread of its own. Maybe it is somewhere.
I get what you are saying. When designing a pack, you care about how much energy (kilowatt hours) it can store. When loading the inverter, you care about how many watts it can output. When comparing cells of different...
I was really interested in the Texas power debacle just in terms of the technical issues and risk assessment vs. cost evaluations. However, when I tried to find useful information, I kept coming across propaganda that uses the most common trick in the sales profession, the false comparison...
I tried to get my older Motorola phone to read the QR codes and it failed. The app ran, but the phone would never identify the QR code.
I had success with a one year old Samsung. It popped up a warning that the app was written for an older version of android, but the app ran, and generally...
Since the BMS really only controls the connection between the B- and C- connections, and does not act on the current at the B+ pad, I would say that the best option is to use the red balance wire and not connect anything to the B+ pad. The advantage of not using the B+ pad is that voltage drop...
@Trukinbear,
Wow! I didn't realize that Battleborn prices were sliding that fast. If that keeps up, I'll be able to build a system out of them when I'm ... about 125 years old, I guess. Better pencil that in on my calendar cause I'm certain to forget to check on them if I don't. :rolleyes...
This is a very complicated topic, partly because of terminology confusion, and partly because of the differences in construction of charge controllers and inverters.
If I understanding correctly, you are asking if one of your battery bank conductors should be tied to the system earth ground...
HaHaHa!
"Would you like a side of popplers and some slurm with that?" ?
-------------------
Seriously though, I've died a little bit inside every time that a news reporter or government authority called this thing a monolith. It was metal plates riveted together, not a solid, one piece...
This is a good point, and why I believe that an all electric system needs to be designed like a hot water system at the household level. I can shift my energy consumption for hot water by a few hours and not notice any difference because I have a tank of hot water available that covers the...
Picture of the 8ah battery after the short circuit test.
Their description of the event was interesting-
It should be noted that their open flame test was on just the plate after the short circuit event. I believe the vapors emitted during the short circuit event can be flammable under the...
The C rate is a way to refer to the current in relation to the capacity of the battery. So for the 160 amp hour battery, a 1C draw would be 160 amps, a 2C draw would be 320 amps. For the 8 amp hour battery, a 1C draw would be 8 amps. It is an easier way to evaluate the capabilities of...
I am I understanding correctly that their instructions have you put an un-plated copper washer between the plated copper bus bar and the aluminum battery terminal?
This seems counter productive to me, as the copper is prone to corrosion if its not plated, and it puts it in direct contact with a...
This is fun because we understand very similar facts, but see opposite solutions. It is a tendency to look at small contributions as insignificant, forgetting about the power of large numbers. When statistics on plastic pollution (from ourworlddata.org) in 2010 say that the average person in...
Newton is a unit of force but it is a little more difficult to conceptualize than the pound.
Because we think of a pound in terms of how hard gravity pulls on something that weighs one pound. It is something that we experience every day. The newton is defined in terms of inertia, how much...
I've tried to make clear here that I'm not advocating that there is one type of battery that everyone should use. I'm just trying to gain an understanding of the options.
In a way, selecting a battery system is like marriage:
Plenty of people are going to have an opinion on what you should go...
Thanks for the reply Steve. I appreciate the information I've gained from you an others on the forum.
This little bit of the spec sheet for the LF280 cells is probably not particularly relevant for general use in solar installations because it was in relation to a 1C charge and discharge...
My experience with delivery time from China to the middle of the U.S.
For heavier items like battery cells going by ship - 70 to 90 days.
For the inverter which was shipped from China by air - 8 days. (that is pretty amazing)
I am of a similar mind on this as @houseofancients . Though I haven't ever said that any one supplier is best, I have reported on my own purchase decisions and the results. However, after seeing several reports of slightly bulging cells, I became concerned that the quality of the products...
I was working on figuring out the date codes on my EVE cells over the weekend, and I assumed that the letters just went down the alphabet with each letter from A on corresponding to the numbers greater than 10. I found out, as the first poster stated, some numbers are skipped, so that is not...
I found this post with a link for the grub screws and nuts.
https://diysolarforum.com/threads/link-to-proper-studs-and-nuts-for-eve-cells.12163/post-149046
Wow.
From their document:
Really? They're calling limping their ship back to Japan "all operations proceeding as planned"? I think that ship already sailed, so to speak.
Hopefully this isn't like the used car market where flooded cars get cleaned up and sold. I'm definitely going to be...
I got the spec from the datasheets on Renogy's website, 175w here, and 300w here.
The coefficients between the two panels were different, -0.42% for the 175w and -0.47% for the 300w, so the 175 watt panels are marginally better at handling the heat.
I used the NOCT from the datasheet. It is...
I'm with Bud on this, but maybe even a step more cautious. The EG4 battery you have can put out at least 125 amps. If the wire coming from the battery cannot handle 125 amps, it needs to be fused at the battery connection.
I have a grandson who didn't understand this principle, and installed...
@spudbudy
Are you sure you have the panel specifications quoted correctly. I don't think that the short circuit current ISC should be less than the maximum power point current IMP. Also, the + and - % numbers are important, along with your expected operating temperature to make sure your solar...
I have had large items delivered to my home, where there is obviously no fork lift. The work-around is to specify a lift-gate truck is required. There is usually a small extra charge, but then they are able to use a pallet jack on the truck to move the item to the lift gate, lower it to the...
Check the specifications on the BMS you are selecting carefully. Only certain BMS models are designed for series operation. They have to have a higher voltage FET for current switching than ones that are not designed for series operation.
JDB as a 150A bms that is designed for up to 4...
The trick would be not to exceed the charge rate or the discharge rate limits of the battery. You would have to watch it like a hawk. A cloud coming over could drop the PV output way down and suddenly the growatt is asking the battery for a bunch of power. You might be able to change settings...
@rin67630, you make a good point about how an off grid system would be sized. I'm looking at battery specs a lot lately because I want a system where, at my most conservative power use, I can go four days without sun. So, in that case, the C rate on discharge wouldn't be a problem, and I did...
I agree with sunshine_eggo that 10A fusing would be sufficient with a 5.83A short circuit current.
Per the manual, you are allowed to use no higher than a 15A fuse.