2Big2B
Free Wheeler
Will Prowse needs to do a formal retraction to his previous endorsements!Friends don't let friends buy Renogy.
(or maybe he has but I missed that?)
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Will Prowse needs to do a formal retraction to his previous endorsements!Friends don't let friends buy Renogy.
Thank you!
Actually I picked up on your rather cute footnote, and hence my pun in reply about "crossing my legs" which was to imply a dead short across two legs of a ciruit... . I had included the basic SOC curve chart along the way earlier in conversation, learned from a deep dive into all of that when building and balancing my own DIY project battery packs a couple of years ago. Basic training for any real dialogue here...
But actually I am still a little mystified about why the BMS is inappropriate for serial connections. Maybe it was common back then? Just like Icom vs Kenwood, Nikon vs. Canon, Apple vs Microsoft... I guess they all have their reasons buried in history.
But limiting the bms like that seems pretty stupid. Who's idea was it to dismiss that half of the potential commercial applications that way for the sake of a few cents of production costs? Did someone in corporate fall asleep in Marketing 101 ? Maybe the design of that bms was to fullfill some government bidding contract requirement that bled into the adoption of that spec into their basic market limitation? Or maybe I am just naieve that it was a rational decision to allow the competition like Power Queen to have such a marketing advantage.
And here I was operating on the assumption that Renogy was king of the hill based upon Will's enthusiasm on his videos about them 4 years ago - an eternity in this market space. Are they publically traded, or are they free to make unfettered blunders like that? There was probably some earlier corporate politics involved. I have an insight about such things because in the late 80's I was spearheading the establishment of the fledgling Canon Printer Division, as lead product / sales marketing and development engineer giving technical sales seminars to potential major distributors throughout the country, flying 5 days a week, two cities a day as we embraced the US market' to make our own foothold. I was a real road warrior back then - when I wasn't running Comdex trade shows or back in HQ working with third party developers gaining software compatibility and establishing our marketing presence. Long story, a lifetime ago...
Here's an aside though... When you look at your driver's license you will see a DMV color photo of you. I was involved with putting it there. An early part of my career was working "Third Party Developer Relations", and was once part of my title. Some where the big league fish like Microsoft, Word Perfect, Adobe, and then the lesser mainstream. Without printer software drivers right out of the box, nobody would buy our printers no matter what magic was under the hood. Every hardware and software manufacturer was intensely scrambling to establish themselves. I had some real amusing independent guys calling me with pitches for our development support for helping them invent and sell their better mousetrap. I had all kinds of weird stuff to have to deal with.
So I got a call from a Doug someone, another self proclaimed President and CEO of a sole proprietorship. What he was asking for was some free donation current and prototype color ink printers for his use in developing software to; aquire an image, process its printing on paper tape, in a world dominated by dot matrix printers. He was in the stage of being able to print on cash register paper receipt tape. He was trying to take it to the next step using our new fangled Bubble Jet printers. State of the art in 1987. Brilliant idea. He also needed our proprietary language programming manual for writing code for our new, not yet on the market product. Big ask. Now I tag "ISV loaner program engineer" to my latest ever changing business card. So, I let Corporate Legal prepare a standard Non-Disclosure Agreement for Doug to sign and I tracked down the proprietary jinglish programming manuals and other cryptic documentation, and together we were able to make enough sense of it he that he went on his way.
About a year later I was working Fall COMDEX ('88 I guess). The Consumer Electronics Dealers Exposition was one of the major marketing seasonal events held in major cities including; New York, Boston, Chicago, Atlanta, Los Angeles, and in this case Las Vegas. It was a corporate duty that I worked booth in all of them; standing in leather soled Florsheim wingtips on a thinly carpeted cold polished concrete floor, keeping and protecting our supply of handout Sales Literature, paper and printer supplies, in 12 hour shifts, weary and thanking god for having had the wisdom to not have gotten hammered at any of the many opening private invite only parties the in the casinos the night before. I learned after doing that once. There is nothing more miserable than trying to pretend being the Corporate image in front of a few thousand people milling through the hundreds of booths with a thousand opportunities to make business contacts.
So I am standing there at about 9:30 or so I guess, first day of the show, Monday. I was still feeling refreshed the brisk walk from my hotel from the to the main Convention Hall. It was a brisk 3 block walk a couple of hours ago, the start of my shift. It also was on about my 3rd cup of coffee, having stopped into the conveniece shop for my walking cup to go. I was in a hurry to get past a gal buying a case of codoms. I guess that is just the 7:30 early Monday morning crush in that neighborhood. Buying buisiness supplies at a quick stop a 7:30 in the morning dressed in some dingy yet colorful wrinkled short dress, slippers, hair looking slept in, her blush past bloom, looking like what the cat dragged in. Or maybe she was the cat. A tunnel rat, more likely.
So I am standing there, in my sharp suit, Canon insignia pin, smiling at the herd that passes through, passes by, or engages. I am on the lookout for booth bandits. These were a rival company with a booth whose team would raid the competition. I would be confronted by some attendee asking me some convoluted question about out new laser printer, of which I would demonstrate. It was to distract me while his partner would innocently grab all the stackes of our booth handouts, to as sabotage, which was rampant. As was our critical paper supplies. On Wednesday morning opening discovered that our entire supply we'd had shipped in had dissapeared. Catastrophe. I was told about it when I started my shift, upon which I hopped in a cab and hit found a big stationary chain store where I proceed to charge an immediate paper resupply, saving the day while everyone else was too busy playing 'cover your own ass'.
So, I think it was on Tuesday that it was brought to my attention that a Doug someone was looking for me. A couple minutes later this very enthusiastic badged business attendee reached out his hand saying "Mr. Hindley, I want to Thank YOU... You made me a Million Dollars! Skeptical, I smile him and said, in my be at New York attitude So, where's my cut ?!!""
When I got back to base about a week later, my secretary left a package on my desk, addressed to me. I opened it up to find a Thank You card and a big solid 1lb chunk of Ghirardelli Chocolate in appreciation. I shared it with the office. Everyone loves chocolate.
As it turns out, he had pioneered a turnkey hardware/software application that he sold to Costco who used it to make first ever instant photo membership cards at Customer Service. Initially, the first ones where cut and pasted on cardstock with packing tape slapoed on, but soon followed by plastic laminated. I really did make Doug somebody a SOMEBODY millionaire, living the goodlife in San Diego.
The following year, another package with a lb of Ghirardelli Chocolate showed up on my desk. I ate that one.
No dilemma.Back to your original dilemma, cooking. This isn’t advice, just a statement of what I’d do. Get a small butane camping burner and hide it on the top shelf of a closet. If the power is out and I needed to heat something up to eat, you get your ass I’ll be discreetly using it with the door locked and window blinds closed.
Hopefully this link works :
The fifth bullet point under “Safety Considerations “ clearly states :
• DO NOT string batteries in series. Doing so can cause catastrophic failure.
You would think that would be the first point made. And it certainly should be in the spec sheet. Piss poor job Renogy.
IF a manufacturer chooses to use a BMS that is unable to handle higher Voltages you simply CANNOT put those batteries in series.
Unfortunately you really need to research what you’re buying nowadays before pulling the trigger.
14.6 (3.65) is a bit high for my taste as well. You can do the math for a 16s and I wouldn’t be a fan either.
3.2V is not terribly scary.
Let me offer some references to chew through and make your own decisions.
First:
How to Find Happiness With LiFePO4 (Lithium-Ion) Batteries – Solacity
By: Rob Beckers You have just sold your first-born into slavery, remortgaged the house, and bought yourself a lithium-ion battery! Now you want to know how to take care of your precious new purchase: How to best charge lithium-iron batteries, how to discharge them, and how to get the maximum...www.solacity.com
Longer, but worth it IMHO :
DIY LiFePO4 Batteries On Boats - Marine How To
DIY LiFePo4 On Boats Last edit;3/26/23:The base of this article was written a number of years ago (2010) but this does not mean the information here is outdated. We have been keeping it updated and have added to it when ever we had the time. This article dealsmarinehowto.com
Both are older but the facts haven’t changed.
Also, for LiFePO4 prismatic, cylindrical or pouch form factor doesn’t matter to me.
Thank you for that Joe.14.6 (3.65) is a bit high for my taste as well. You can do the math for a 16s and I wouldn’t be a fan either.
3.2V is not terribly low but there’s not a ton of energy left below there.
Let me offer some references to chew through and make your own decisions.
First:
How to Find Happiness With LiFePO4 (Lithium-Ion) Batteries – Solacity
By: Rob Beckers You have just sold your first-born into slavery, remortgaged the house, and bought yourself a lithium-ion battery! Now you want to know how to take care of your precious new purchase: How to best charge lithium-iron batteries, how to discharge them, and how to get the maximum...www.solacity.com
Longer, but worth it IMHO :
DIY LiFePO4 Batteries On Boats - Marine How To
DIY LiFePo4 On Boats Last edit;3/26/23:The base of this article was written a number of years ago (2010) but this does not mean the information here is outdated. We have been keeping it updated and have added to it when ever we had the time. This article dealsmarinehowto.com
Both are older references but the facts haven’t changed.
Also, for LiFePO4 prismatic, cylindrical or pouch form factor doesn’t matter to me.
I am building a solar battery charger for my wheelchair that I can hang in my patio. I am probably the first to try that!!While you can’t run a pair of 600 watt inverters in parallel, you can run them separate but io the same battery. One could provide power for a few lights, laptop computer, maybe a cable box or cable/DSL modem. Use the other one for a tv if its power requirements are less than 600 watts. A 100 ah battery will give you a few hours but you’ll need to conserve power since you don’t have any way of charging them without the grid. For cooking or heating canned foods, you’ll get much more bang for the buck with a small butane burner. Think of this as a camping trip without the mosquitos.
You are right. I happen to have a single burner propane camping stove that would work in stealth...This is not true as an absolute. 24V allows the use of smaller conductors.
Doesn't work like that. Each 120VAC power outlet of your home can supply at least 1800W of power, but you don't think twice about plugging a 10W light bulb into it.
Same thing with the inverter.
Besides, what I'm reading is that 40A is the maximum input current. 40A * 24V is 96W
Quality is a mixed bag, but some are better than others. One thing of concern is they all have high idle consumption and low efficiency.
There's nothing wrong with having more than one inverter. This unit would likely do very well to efficiently run a handful of lower power items. You can even connect multiple inverters to the same battery.
Making heat with batteries is a bear. I would take that off the table and look for a fuel burning camp stove/grill for grid-down cooking.
Budget limitations are tough for a project like this. It's best to start with a very specific goal, e.g., I want to power this, this and this for X hours per day and then design a backup system around it.