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Small Cabin Forum / Off-Grid Living / FLA Rescue
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gcrank1
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# Posted: 16 Dec 2021 10:55
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The vehicle start/no start load test is pretty definitive, a good test if already hooked up in a vehicle.
With our winter temps dropping Im soon into prime load testing/battery health season.

paulz
Member
# Posted: 16 Dec 2021 17:30 - Edited by: paulz
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I hauled batteries back to the grid today. Finally got smart and instead of hauling the batteries, especially the huge Caterpillar batts, to the battery bench I just brought the chargers out to the truck.

I asked this before but still don't get the reasoning why I can't jumper a 12v FLA to my 12v LFP bank when it's sitting at 13.2v and charging from the solar. Wouldn't it be just another draw until it reached 13.2?
20211216_134749.jpg
20211216_134749.jpg


gcrank1
Member
# Posted: 23 Dec 2021 20:08 - Edited by: gcrank1
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My last old ups agm has effectively died as of my Eve of Christmas Eve visit today.
My routine is to unlock the power house soon after arrival and eye the scc readout. As typical it was at 14.4v. Powered up the inverter, with some draw the readout dropped quickly to 12.9 which should be fully charged (and it has been on solar, no load, since 12-18).
Opened the cabin, lit the LP furnace, turned on the cheap ceiling fan to med and the old portable am/fm radio. I calc all the amps draw at 4-5.
Went for a walk, did a few projects....was in and out, all went well until about 1.5 hrs out and the inverter started cycling at low-voltage. The readout was 10 something. So, less than 10amps draw over 1.5 hrs! Yeah, it was cold, but.....
Im calling that battery done even though I cant stick a fork in it.
This might be the last visit for a while and no sense running the scc 24/7 for no good reason so I discon'ed the array, then the bat to sit until spring.
Im right on the edge of buying a 100ah lfp ready to run to keep warm and charge at home then carry up when we go. Come spring I'll hook up the salvaged M-DC to keep idling along on the solar.

paulz
Member
# Posted: 23 Dec 2021 21:18
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Brought the 4 Delco Marine FLAs, long suffering since solar charging effectively ended at the shop, back to the grid for charging. They were reading 12.1-12.2. They've all taken a full charge and survive the load tester afterward, we'll see in a day or two. They have a little window on top with a normally green dot showing, it's now red even after charging so that's not good. I forgot to bring my new hydrometer along with them.

I do have those little desulficators on there...

paulz
Member
# Posted: 21 Jan 2022 19:48
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I was just reading about some guys using 20v solar panels with a buck boost converter set to 14v, no SCC. The argument against this is no three stage charging. AFAIK, my car just charges at 14v anytime it's running.

gcrank1
Member
# Posted: 21 Jan 2022 21:21
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About all the regulator specs Ive looked at for my older vehicles have been that 14.0-14.5ish volts. After this messing about with solar charge controls and now the sensitive LFP charge parameters Im thinking the typical automotive/motorcycle charging systems are pretty much quick & dirty. Well, the typical automotive battery can take a lot of abuse!
For grins last summer I took my old 15w solar panel, sans scc, checked the output voc (upper teens?) and hooked it straight to an old sealed battery jump pack. With the limited solar 'hour' I had it topped it up some and didnt feel warm. Seems to work IF one has limited exposure.
But 'safer' is what I normally do, cig lighter port in the suv rear to the cl port on the jump pack for the trip home and back. Its a handy unit for lots of things. I took the jump cables off and put on a pair of lighter duty clamp leads; never used it for jumping anyway.

FishHog
Member
# Posted: 22 Jan 2022 08:31
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Quoting: paulz
I was just reading about some guys using 20v solar panels with a buck boost converter set to 14v, no SCC. The argument against this is no three stage charging. AFAIK, my car just charges at 14v anytime it's running.


Pretty sure there is a voltage regulator built in the car system (don't know exactly how that works), that drops charging to the battery when its full and keeps the rest of the generated electricity for the various car functions.

I don't know the specifics on how that works, but I do know on my van which has a dc-dc charging system, the van battery gets topped up first, then any excess power will be dumped into my house battery.

paulz
Member
# Posted: 22 Jan 2022 10:51
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Yes that's right, the old mechanical regulators I'm familiar with have both voltage and current control. It would have to be more like an old style battery charger and monitored.

curious
Member
# Posted: 22 Jan 2022 10:56
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Quoting: paulz
my car just charges at 14v anytime it's running

Maybe.

As FishHog said, what about the dingus called a voltage regulator? Built into alternators these day of a part of the much larger control system.

On some newer vehicles the voltage can be seen to rise to 14+ volts right after starting and then taper off as the battery is replenished. Then, if no big loads are operating, the voltage may stay down in the float range while driving. Turn on the bright headlights and voltage will rise. Lots of "smarts" in newer vehicles that do depend on those in-short-supply chips.

As for the online guys doing unusual things with solar and batteries, it is not necessarily good or better just because someone posted something online.

gcrank1
Member
# Posted: 22 Jan 2022 11:05 - Edited by: gcrank1
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Seems to me that panel rig with Buck sounds like it would charge a 12v LFP to 90ish % like the Meanwell power supply set to 14.0 that we are using (though it has a 40a output, the Panel & Buck is likely much less).
In fact, my mppt scc is taking in from my array and if set-point is 14.0v will do the very same thing in a more complicated way.
The battery will only take the amps (current) that it can take, its the volts that 'push it in'. The voltage has to be some higher than the battery voltage (think like water levels and what flows where/why). But if the voltage is set too high is when you get the overcharge or, if BMS equipped, hit the HVD.

paulz
Member
# Posted: 22 Jan 2022 11:24
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Quoting: curious
As for the online guys doing unusual things with solar and batteries, it is not necessarily good or better just because someone posted something online.


Right, that's why I brought it up here, as gcrank1 and travellerw have actually done it. I did too off an 18v panel last week, think I mentioned it in another thread, and it worked great, but the panel was not in direct sunlight and I monitored it closely.

I see for 20 bucks you can buy a controller just for this purpose, not much more than a buck converter, think I'll try one.
Screenshot_2022012.png
Screenshot_2022012.png


gcrank1
Member
# Posted: 22 Jan 2022 12:01 - Edited by: gcrank1
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100w/12-13v = about 7a, pretty much what my old basic 'switching?' solar 7a reg was for my 15w panel; think they used to be about $10.
Id want to be careful on the peak voltage if ever intending to use it on LFP (pref adjustable like the Meanwell PS but not likely at that price-point).
I think those little units only put out their max 'rated' amps even if hooked up to a panel that puts out more.
Thats ok if the C-rate of the battery is within that or you just want to go slow & easy, like with a maintainer?
I do think a cheap cc on a small panel is a smart thing to do, and certainly necessary on big arrays.

paulz
Member
# Posted: 24 Jan 2022 09:44
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I got one of those little controllers. Going on a week vacation, will try it out when I get back.

Speaking of the Meanwells, I think I mentioned my spare died, I may have had the 120/240 switch in the wrong place. Took the cover off and performed my usual electronics troubleshooting: the fuse is OK.

I'd sure like to fix it, probably something simple. Hoping someone, I know @travellerw knows caps and stuff, can point me to where the problem could be and how to test.
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20220119_0848361.j.jpg


gcrank1
Member
# Posted: 24 Jan 2022 10:18
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After that fuse check Id start looking the board/components over close for over-heated signs, wouldnt be surprised to find a nickel resistor or such blew. Thats as far as my 'complicated electronics knowledge' goes.....
Do you have a local tech-school with an electronics course? If so, go talk to the instructor, might be your unit could be a 'project' for one of the ace students.

travellerw
Member
# Posted: 24 Jan 2022 12:47
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Quoting: paulz
I'd sure like to fix it, probably something simple. Hoping someone, I know @travellerw knows caps and stuff, can point me to where the problem could be and how to test.


I don't work on this stuff all the time.. but I can't see how setting the switch to 240V and then plugging into 120V would hurt the supply.... but I could be missing something. What is the supply doing.. Is there absolutely no output?

Unfortunately if there are no obvious signs (burn marks, bulging caps, ect) then a power supply can be a tough thing to troubleshoot if you aren't used to working with them (and dangerous).

Most technicians would begin by powering up the supply and then measuring voltages at different points. So at the very least, you are dealing with live 120V while you are sticking your multimeter pokey bits in there. However, many power factor corrected supplies will actually step the voltage up (as high as 500-600V) before bringing it back down.

Because of the danger factor, I usually start by testing the Mosfets and Bridge rectifiers (the devices bolted to that big heat sink). These can be checked with the supply powered down. Get the number off the device and find out if its a FET or BR, then there are good videos on Youtube how to test those devices in situ. 7 times out of 10 I find one of the devices has gone dead short.

gcrank1
Member
# Posted: 24 Jan 2022 21:16 - Edited by: gcrank1
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Returning to the FLA, I finally gave it a follow-up capacity test today. It is supposed to be a '109 AH Everstart/Walmart Deep Cycle Marine'. Ive heard these are 60-80AH.... and I dont know the back-story of this one.
It recharged and has held quite well in my cold basement (50*f at the floor), this morning was at 12.68 (just sitting for weeks). Even with FLA voltage is not as reliable as hydrometer, mine is at the cabin .
Hooked up my 'test unit', the portable mini-fridge that draws about 4.8a, noted the time and returned to re-read under load every hour for 4 hrs. At 4 it was 12.09v, a 19 amp discharge.
Let it sit 2 hrs and got a bump back to 12.42 (about 70ish % soc?) thats .33v above the sagged discharge, or on an extrapolated 20 hr rate it is an est. 70ish ah battery. But its at 50ish* so maybe its a nominal 80ah?
Yeah, lots of numbers.....Im a numbers guy, and its deep winter here.....
Thing is that it appears the reports are right, these '100ish ah' Walmart deep cycle marine bats are NOT.
Used to be for about $100 @ (now locally $120!) you could get one or two of these for a small system and be ok, but at only 70-80 ah gross, 35-40 ah max usable if you want any kind of bat life they are not a bargain. At $250ish for a pair of poor old FLA you could spend $60ish more for a pre-built LFP 50 ah and have so much more/better battery.
Premium 'deep cycle' FLA bats will cost more. It could be we are at the tipping point now where just the buy-in cost vs LFP, even pre-built is close enough that it is time to let the old-tech go?

paulz
Member
# Posted: 26 Jan 2022 10:09
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Thanks guys for the advice on the dead Meanwell. Will follow up, I'm in Vegas for a weeks vacation. You wouldn't believe the housing going up down here, I'll try to get a photo, must be a thousand high rise condos going up right along the freeway. Sure makes me grateful of my cabin property.

Anyway, gcrank, can't let all the old tech go just yet, got too many trucks, tractor and utvs around my place that still need FLA. It's crazy to put new batteries in when they sit for months at a time. I keep a handful of FLAs on the charging bench for when I need to use one. And with my little desulphater gizmo going they should be good as new in a year or so.

But yeah for cabin use the LFPS have been fabulous. Going to be interesting to see the SOC when I get back after a week of charging with no use. Hopefully not on fire.

When those 10 year old Valence LFPs give it up I'm going to have to come up with 500ah of replacements, not looking forward to that.

travellerw
Member
# Posted: 26 Jan 2022 13:46
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Quoting: gcrank1
t $250ish for a pair of poor old FLA you could spend $60ish more for a pre-built LFP 50 ah and have so much more/better battery.
Premium 'deep cycle' FLA bats will cost more. It could be we are at the tipping point now where just the buy-in cost vs LFP, even pre-built is close enough that it is time to let the old-tech go?


A couple times a year, Costco will put 6V golf cart batteries on for $100cdn ($80usd). $200 for a 200ah (100ah usable) is a pretty good deal, at least up here. A LFP at 100ah starts at $500cdn here (cheap no name brand on Amazon Canada). About $650 for something I would trust with high and low temp cutoff!

Now on another note.. I came across this video yesterday that piqued my interest. Its danger redneckery, but interesting results nonetheless.

https://www.youtube.com/watch?v=8CxFpIoKwy0

paulz
Member
# Posted: 26 Jan 2022 19:36
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Quoting: travellerw
on another note.. I came across this video yesterday that piqued my interest. Its danger redneckery, but interesting results nonetheless.


LOL, looks like something I would do. In fact, the Meanwell power supplies will put out 40A at 16v, close to what he's doing. But since gcrank has one now, and started this thread, I nominate him to test it.

travellerw
Member
# Posted: 26 Jan 2022 20:00
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Quoting: paulz
LOL, looks like something I would do. In fact, the Meanwell power supplies will put out 40A at 16v, close to what he's doing. But since gcrank has one now, and started this thread, I nominate him to test it


He actually went to 120A in the end (was impressed the welder could take it)... I found it interesting. When we lived on our FLA batts, we would run an equalization/desulphation cycle about every 3 weeks. But only like 16.0V

We also had quite a few friends that would "revive" batteries with Epsom salts. it seemed to work, but was pretty short lived. It would revive them for about 3 months before it would fall off a cliff.

gcrank1
Member
# Posted: 26 Jan 2022 20:49 - Edited by: gcrank1
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LOL, ya'all musta heard I was a 1st born son, type A, risk-taker hey!
Where, oh where is the 'Dont try this at home, Im a trained professional'?
He says "dont do this inside" then does it inside. How about throwing together a simple wood frame and some plastic sheet as a safety enclosure? Just like a simple small paint booth.
"use only distilled water"; ie, no contaminants...then pours it in a dirty top battery. And overfills.
Oh, by the way, "Ive never done this before" but I'll do right here on vid 1st time for the world to see.
Hooks up to a welder without a cheap plastic raincoat or a face shield and sticks his face pretty much over the thing cranking up the amps......
What could go wrong?
Well, yeah, its 'redneck' alright; pretty much on the edge imo.
My hands get itchy just watching him messing about.
Dont wear any clothes you really like, bat acid especially likes to eat cotton denim. Dont ask.....
Fwiw, I blew the top off a big agm ups 140ah 12v a few years ago on an actual 'big' charger not even on boost. I had an unrelated med emergency and the battery was unattended for a week; got home and it was blown But It Was Outside.
Do Not Try His Method With A Sealed Battery!
Or an LFP ('we' all know this, somebody who doesnt will read this)
I have run my charger (not the Meanwell) at higher than recommended C amp rates for a given battery ah for about an hour at a time (check case temp by hand every 15-20 min.), let rest for several then repeat. It has been no where near as aggressive as this vid and I have revived a few; enough that it is my go to method.

paulz
Member
# Posted: 27 Jan 2022 10:27
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I was telling a friend how great these pocket size jumper packs are and how they will quickly start an engine that won't even turn over otherwise. He asked how they can dump so much current down those little cables so quickly. Got me on that one, I have not cut or closely examined the cables on mine but they sure look small.

Anyway, as a quick FLA rescue they are superb.
Screenshot_2022012.png
Screenshot_2022012.png


gcrank1
Member
# Posted: 27 Jan 2022 10:46
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I have wondered about those wires gauge too.
Only thing I can figure is the device is to be hooked to the battery for a bit, it dumps its stored amps into the low bat quickly (because its lith tech has very low resistance) this 'equalizing'/pumping up the low bat.
Then arent you supposed to discon it before cranking (which is the BIG load discharge)?
Btw, that is pretty much how the old shop bat chargers work, on the start function they boost charge very quickly (never metered one, maybe high volts and amps?), you do this for a limited period, maybe 10 min (or do they have a cut-out function after x min?) and start the vehicle. Best to not leave it on Boost unattended.

paulz
Member
# Posted: 27 Jan 2022 11:02
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Quoting: gcrank1
Then arent you supposed to discon it before cranking (which is the BIG load discharge)?


Hmm, I never have,and they still work...

Last week I ran the old UTV (I have two now, both freebies..) down the hill, running at idle, using compression to slow it down. When I got to the bottom it was flooded, wore the battery down trying to clear it out. Hooked up the jumper pack, boom, off and running. I think next to LFP and LED lighting they are the best tech breakthrough going for me.

But yeah, a mystery how they deliver so much current through those cables.

gcrank1
Member
# Posted: 27 Jan 2022 11:15 - Edited by: gcrank1
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Lets think like we do for solar?
Low voltage needs big wires to run high amperage
Higher voltage lets us run smaller wires
Even 10 ga. awg is good for 30amps 0-6'
Maybe next time you get a chance, use the VOM and read the output from the Jump Pac open circuit and hooked up.
Could it be the JPac is pushing with some higher voltage thus the smaller ga. wires are Ok?
Im also curious how long you JPac would power a dc led light; ie, a small, light weight, easily portable and handy dc power pac for camping, etc.

paulz
Member
# Posted: 27 Jan 2022 11:28
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They have built in USB out ports, flashlights and maybe 12v low current outlets, I'd have to check that. I don't think I brought one on the trip I'm on this week. Got a good battery.

Mine also has a 'START' LED that lights up when you hook up the cables, not sure if they would measure anything open voltage, but I will check.

gcrank1
Member
# Posted: 27 Jan 2022 13:55
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Maybe Im over-thinking again (what! Me?), one of those units might just be a micro-mini aio unit for camping/super small scale as is, and still be able to jump start a car.

ICC
Member
# Posted: 27 Jan 2022 15:22
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I have limited experience with those small portable jump packs. My brother has one, not sure which but it was somewhat costly. The one time I saw it used it was connected to the "dead" battery, a button pressed to activate it and then the vehicle being jumped was started. No wait period. No need for large cables when it takes a normal quick shot to crank and start the engine.

I believe that is how they are meant to be used. An engine that is in good shape but with a dead or very discharged battery will start quickly when cranked with a good battery.

I have had dead batteries on various machinery go dead from no use, no maintenance charge, etc. They never need to be cranked and cranked and cranked for an extended time. At least not is recent times. Back when we had mechanical fuel pumps and carbs with float bowls that might evaporate dry when left unused for long periods a long crank was sometimes needed. Once a good battery was connected/jumped the engines would start just like normal. Not much more than a key bump, maybe a second at most. Needing to crank the engine for an extended time would overheat small wires. Most likely the jump pack would not be able to supply power for an extended crank.

I don't have to deal with sub zero temperatures much here at home, but it does seem to me that a vehicle that is properly prepped for sub zero temperatures should not need extended cranking. If it does, a little handheld pack is probably not going to be the lifesaver one wants it to be.

You cannot use higher voltage as a substitute for small gauge wires as modern vehicles have electronics that can be damaged with too high a voltage. Back in the 60's when we still had equipment with 6 volt systems we did jump some with 12 volts but we were just cranking a simple engine. No electronics in sight.

gcrank1
Member
# Posted: 27 Jan 2022 15:55
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Just conversationally, doesnt the target 12v battery become the 'buffer' even with a higher voltage source on it? Ie, it wont pass on, say 18v from the JPac that os pushing amps into it, basically acting as a dampening voltage regulator.

ICC
Member
# Posted: 27 Jan 2022 19:27 - Edited by: ICC
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No, or at least I don't think so. I know from first hand experience that boosting a 6 volt tractor with 12 volts makes the starter motor turn faster. The 12 volts goes straight thru to the starter. It will pass thru to any connected items.

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