Battery at 12.3v under load. When load removed its 12.6v this isnt discharged?

[73powerstroke]

I don't normally post up what I have for a background, but for you, I'll make an exception.

The first lesson you need to learn as an automotive mechanic, which I am not, I am an automotive master technician of over 35 years of shop ownership; is when constructing anything, whether it is an electrical circuit, an exhaust system, building a house, virtually anything, you should make it look like you knew what you were doing. If you don't know what you're doing, then you should educate yourself on the proper methodology and practice.

What I'm trying to understand is how anyone could go thru formal training as an automotive tech in this day and age and not know what load testing of a lead acid battery truly is and how the results should be interpreted. Then we move on to voltage drop testing of a circuit, how it should be performed and determining resistance in a circuit.

If you don't know, then get educated. If you want to hang out with real professionals in the industry, then I suggest you step up to the real university of automotive repair knowledge online, known as IATN, International Automotive Technicians Network. You can join for free with a basic membership as long as you qualify. http://www.iatn.net/

I've been a sponsoring member there since 2004. The best in the industry hung out there, there was some that left or passed away over the years but the knowledge there is top notch. Step up your game, become a true professional. Redneck crap in the days of increasing technology, complexity and systems integration is no way to go thru life, much less a career. And be prepared to have a thick skin, you will have members call you out if you try to con your way thru, sharp bunch but you will learn from mistakes too.

The reason I posted this, and no, my complete business model is not entirely as an automotive technician, is because I see what I consider very substandard methods used to build an electrical circuit in your photos. While you believe if it "works", it's good enough, however over the last 40 plus years of turning wrenches and repairing electrical circuits and components, I can tell you the workmanship you have with your current standards is destined for failure and quite likely catastrophic.



Instead of being good at breaking stuff, you should strive to build the best "product" you can. It takes not only an investment of your time to gain knowledge but also to put it into practice.

I guess I'm not doing too well here.
I won't excuse that. I cut corners and used what I had easily available.
I was just trying to see if I could run a window ac unit off a few cheap batteries and hf panels originally.
I got hell for the panels. At 6 it worked for intermittent use.
People told me about san tan solar in gilbert az so I drove there a few time and bought 8 panels and 2 epever 40amp tracer 4210an cc and pv wire, pv connectors, branches, shunt meter, 6ga wire for cc to battery. And 6ga lugs. The rest wasn't easily available.
I got 2ga wire from verne Lewis welding supply. Some lugs from them but too big of holes. So I made some. I crimped them slightly and flowed solder into the connection. I dont have any protection on anything. I have Dean hobby connectors where the 10ga wire feed the cc solar in on one the other was too short and has 14ga wire for a few feet.
I geuss I should probably tear it all down and put it up. I don't know what I'm doing here. And every thing looks bad.
I went to lake Washington technical College during the 2008 crash. I got a quick ibest automotive technician certificate of completion. 1 year plus.
We glazed over the basics. Deivability, diagnostics, hybrids, brakes and suspension, engine, shop principles.
I was still actively drinking alcholicly back then . Ruff times.
I went on to work for several midas shops and several smaller import shops. I was unreliable due to my heavy drinking. Jobs came and went often. My only plus is im im ok with diagnostics and can slove hard problems others fail at. Ive always used a load tester on batteries. I dont own one. Temperature comp on some others just big toaster load boxes, voltage drop is something i understand, and use alot, like the inverter has some vd even with 2ga wire, i should have bought the 00/2 set but oh well. As the v drops on the inverter the current demand increases, it sucks...Otherwise im a terrible mechanic and i don't enjoy it anymore where i used to when i was into fast cars. Now i just fix my high miles diesels and avoid automotive work.
so i guess its not acceptable to say im a auto mechanic.
I have zero interest in working automotive unless I own the shop. I'm 45. I'm not fast. And I'll never beat the flat rate. So I don't work flat rate unless it's a modified guarantee. In Washington state average pay was 20 here it's 15 or less. I cant live off that with 3 kids to support.
Anyway I appreciate the reality check. I was going to go to San tan solar tomorrow for fuses and breakers and pv panels and some extensions but I guess I'll scrap that idea and I'll take this stuff apart before something bad happens.

 

[Don B. Cilly]

Same or opposite.

Opposite. Use a bus bar if they don't fit on one lug.

Originally I thought each on goes to a different battery might help balance things.

You want to treat the three paralleled batteries as much as possible as if they were one big one.
So all positives bottom right, negatives top left.
-

 

[73powerstroke]

Opposite. Use a bus bar if they don't fit on one lug.



You want to treat the three paralleled batteries as much as possible as if they were one big one.
So all positives bottom right, negatives top left.
-

I'm just going to undo it all its obviously not safe. I don't know what I'm doing here

 

[Don B. Cilly]

You're here to learn, that's what you're doing ;·)
It's not that complicated. Granted, those batteries aren't (probably) very good, but to start learning they're OK.

Just start with the basics. First, work out how much power (W) you're going to need. If it's AC, get an inverter that will supply that without sweating too much. Then provide the batteries to supply that. Then, enough panels and charge controllers to recharge them.

If you're worried about "something bad" happening, first put a good fuse on the positive pole. Then check your wiring. If in doubt, ask here.
-

 

[featherlite]

73powerstroke,

I started out four years ago knowing nothing about solar systems. I bought two Walmart batteries and charged them with Walmart automotive chargers. I thought 50% state of charge was 6v. I could not figure out why the batteries only lasted about six months. Fortunately, back then, Walmart would replace them under full warranty. I got new batteries on a regular basis.

Then I found this forum. What a God send!

I have been studying intensely for four years now and sometimes still feel like a moron.

However, I keep coming back to this forum to take my nightly intellectual beating. Some of the guys on this forum are incredibly knowledgeable and are very generous with their time, for which I am grateful.

I strive for progress rather than perfection, so I keep coming back.

In any event, I appreciate your honesty and have enjoyed reading your comments. Easy does it!

 

[Zwy]

I'm just going to undo it all its obviously not safe. I don't know what I'm doing here

Every setback in my life was always an opportunity.

In the end, I came out as better person, a better professional and gained knowledge plus learned from any mistakes. Life is not perfect, don't expect yourself to be.

Only you can determine your fate; either you quit or you push yourself to move on and improve. The man that started this forum faced many challenges, yet he pushed himself to make his life better. If you don't know his whole story, then you should look it up.

 

[73powerstroke]

Every setback in my life was always an opportunity.

In the end, I came out as better person, a better professional and gained knowledge plus learned from any mistakes. Life is not perfect, don't expect yourself to be.

Only you can determine your fate; either you quit or you push yourself to move on and improve. The man that started this forum faced many challenges, yet he pushed himself to make his life better. If you don't know his whole story, then you should look it up.

So what's stronger? Hydraulic crimped or soldered? I dont have a Hydraulic crimper. I don't have a easy way to mount the shunt and connect cables on that post because of how thick the shunt is.
I really need to go to a 24v system .
For me I'm lucky to be alive. Lucky to be a father. Lucky to have a roof over my head. Lucky to have anything. I could be doing much better but it could be alot worse.
My problem is I worry about what others think instead of trusting in my self.

 

[73powerstroke]

You're here to learn, that's what you're doing ;·)
It's not that complicated. Granted, those batteries aren't (probably) very good, but to start learning they're OK.

Just start with the basics. First, work out how much power (W) you're going to need. If it's AC, get an inverter that will supply that without sweating too much. Then provide the batteries to supply that. Then, enough panels and charge controllers to recharge them.

If you're worried about "something bad" happening, first put a good fuse on the positive pole. Then check your wiring. If in doubt, ask here.
-

I'm concerned I have no fuses. Or circuit breakers. I was looking at some. Double vs single? I really dont have anything to mount this to. I have my 2 cc on a Costco rack and wires to batteries.
The problem is I didn't plan to go this far.
I bought a 100w panel and a group 31 for just that panel and a 2000w inverter. That wad all i wanted.. something that could charge my battery for my ham radios.
Then it snowballed.
I had 6 100w hf panels at first. Now
I have 8x 240w panels 2x 40a epever mppt cc, a 2000w hf inverter.

 

[Don B. Cilly]

Double vs single?

If you're really worried, use a class T fuse. Me, I had one of these cheapos save everything from a dead short (long story).

The fuse/breaker didn't survive it, but everything else did. The BMS didn't even blink.

I have 8x 240w panels 2x 40a epever mppt cc, a 2000w hf inverter.

Hey, you have decent SCCs, quite a few panels... is your inverter 12V?
Because, to charge your radio battery, you don't even need one. To do other things, you might.
So, what do you plan to do with your solar rig? Start from that.
-

 

[73powerstroke]

If you're really worried, use a class T fuse. Me, I had one of these cheapos save everything from a dead short (long story).
View attachment 101385
The fuse/breaker didn't survive it, but everything else did. The BMS didn't even blink.




Hey, you have decent SCCs, quite a few panels... is your inverter 12V?
Because, to charge your radio battery, you don't even need one. To do other things, you might.
So, what do you plan to do with your solar rig? Start from that.
-

I have been powering a 5000btu ac unit during the day. It's a harbor freight modified sine 12v 2000w inverter.
With my 240w x8 panels =1920w÷14.4=133a - I only have 2 40amp cc 80=53amps left on the table I could be using. I need to address that. I need another 2 cc if I stick with these limitations of 100v pv input epever. I'm not sure I want to buy more of them.
So can't fuse that yet. And I still might get 2 or 4 more panels. Then the batteries. Geez. Let's say they are ok. I have 50 to 60a draw w ac. But I can't really run anything else at same time. I would actually like to run 2 5000btu ac units. So deciding on a fuse or breaker for batteries could get changed. Like I said I don't know. Then 24v ? Bigger inverter. I wanted to get a 24v inverter from santan today since we aren't busy

Reliable 2000W 12V Inverter 120VAC - SanTan Solar Store

Buy our Reliable 2000W 12V Inverter 120VAC, great design with amazing technology. Get today for only $250

store.santansolar.com

 

[OzSolar]

So what's stronger? Hydraulic crimped or soldered? I dont have a Hydraulic crimper. I don't have a easy way to mount the shunt and connect cables on that post because of how thick the shunt is.
I really need to go to a 24v system .

Crimped is the official answer but that's not a hornets nest I'm swinging at today.

For temporary set up and testing purposes I often use these mechanical lugs and scraps of wire I already have. Once I've got the system components all spaced out nicely I then make up the final cables. You can also easily drill out the hole a bit to match what you need as well. I always have them around and they are reusable. Try to get the ones that use the Allen head as the straight blade will strip out easily. I've ran 100's of amp through them without any issues.

24v is and 48v is great. Personally I think it's ridiculous that they make 12v inverters over ~1500 watts.

 

[73powerstroke]

Crimped is the official answer but that's not a hornets nest I'm swinging at today.

For temporary set up and testing purposes I often use these mechanical lugs and scraps of wire I already have. Once I've got the system components all spaced out nicely I then make up the final cables. You can also easily drill out the hole a bit to match what you need as well. I always have them around and they are reusable. Try to get the ones that use the Allen head as the straight blade will strip out easily. I've ran 100's of amp through them without any issues.

24v is and 48v is great. Personally I think it's ridiculous that they make 12v inverters over ~1500 watts.

The welding cable lugs are alot cheaper than what was at home depot. Unfortunately they use a 1/2 stud like my big miller dialarc hf 310amp machine that I bought them for . They contact alot less surface than I like on battery. Originally I made some nice 6ga thhn jumpers but they got warm. I don't like warm wires. According to my chart 6ga was supposed to be ok but I would rather go bigger and not lose power. The recommended 2ga inverter cables suck. I have too much voltage drop and as battery drains that just gets worse because lower voltage means more amps now. Hf inverter box says use their 2ga cables for 2000w inverter. I should have gotten the shorter 00/2 cables. I guess I could exchange them still. Hmm

 

[Zwy]

The welding cable lugs are alot cheaper than what was at home depot. Unfortunately they use a 1/2 stud like my big miller dialarc hf 310amp machine that I bought them for . They contact alot less surface than I like on battery. Originally I made some nice 6ga thhn jumpers but they got warm. I don't like warm wires. According to my chart 6ga was supposed to be ok but I would rather go bigger and not lose power. The recommended 2ga inverter cables suck. I have too much voltage drop and as battery drains that just gets worse because lower voltage means more amps now. Hf inverter box says use their 2ga cables for 2000w inverter. I should have gotten the shorter 00/2 cables. I guess I could exchange them still. Hmm

Crimped cable and hydraulic at that. This is the one to buy, I've owned hammer type which are not a solid crimp, the large pliers type, really suck getting the handles closed under a hood or in tight spots. https://www.amazon.com/TEMCo-Hydrau...hvlocphy=&hvtargid=pla-4583932713641904&psc=1

Best $175 I ever spent when it comes to battery cables. Buy the right tool the first time and if it lasts a lifetime, it is the best deal you could buy. Back in the day, I was happy to buy the large pliers type for $150 in the pawn shop, this is a way better crimper.

Every connection has resistance, resistance will cause heat. In the case of soldered lugs, the heat can cause the solder to melt and the cable to come out of the lug. Nevermind the voltage drop created due to the resistance.

The hydraulic crimper will crimp tight, there will not be oxidation of the connection and the strands are cold welded due to the pressure.

In you example above, if you voltage drop across a connection and are seeing over 0.5V, then you have excessive resistance. It may not be the gauge of wire at fault but rather the resistance of the connection.

For the 2400W inverter in my truck backseat, I ran 2/0 cable, however the length is well over 15 feet. Find a good DC calculator to determine wire size, there is one in the resources section here.

 

[brb58]

I am an EE and worked in an automotive OEM production environment for awhile including EV. Always crimp. Its a much better joint. The secret is to buy quality crimp connectors and a quality crimper that uses actual AWG dies and not metric dies if you are using AWG size crimp connectors.

My large crimpers are Greenlee and they were over $300 but the one that this guy talks about is a good one:

Making Your Own Battery Cables - Marine How To

Pick Your Crimp Tool FTZ 94284 & Ancor Hammer Crimper TEMCO TH0005 & FTZ Bench Mount BUY FTZ 94284 CRIMP TOOL - BAY MARINE

marinehowto.com

FTZ Correct Crimp Heavy Duty Lug Crimp Tool

FTZ Correct Crimp Heavy Duty Lug Crimp Tool PN 94284 Crimps to UL specifications (when properly calibrated)

baymarinesupply.com

This is an excellent description how to crimp small wires. I actually bought his tool while he was still selling
it.

Marine Wire Termination - Marine How To

Marine Wire Termination - Tools of the Trade MHT Recommended Tools: The products below are our top picks for crimp tools. RecommendationsI include; PRO GRADE, MARINE GRADE, & PENNY SAVER GRADE. Every tool recommended BELOW, we have tested here.

marinehowto.com

I buy all my crimp connectors from here. They used be genuinedealz and had free shipping. They now charge for shipping so I buy more at a time to make it worth it.

Custom Cable and Wire | Marine Grade Cable and Wire Products

Custom Cable and Wire is home to custom made battery cables and the best quality US made UL 1426 marine grade wire products for your boat, rv, trailer, auto, solar, atv needs. Next day shipping available on most orders.s

www.customcableusa.com

For small wires, this is the tool I used to use. When I bought it from the Marinehowtosite, it was only $130. Trying to find where you can get it cheaper for friends that are lookig.

Heat Shrink, Solder Sleeve Ratchet Crimp Tool - 24-10 Gauge

This ratchet crimp tool is specifically designed for crimping 24-10 gauge heat shrink, nylon and vinyl insulated terminals. The ratchet release prevents insulation damage on your terminals.

www.delcity.net

My motto is crimp when you can...solder when you have to. For anything bigger that 10AWG....always crimp.

 

[73powerstroke]

Crimped cable and hydraulic at that. This is the one to buy, I've owned hammer type which are not a solid crimp, the large pliers type, really suck getting the handles closed under a hood or in tight spots. https://www.amazon.com/TEMCo-Hydrau...hvlocphy=&hvtargid=pla-4583932713641904&psc=1

Best $175 I ever spent when it comes to battery cables. Buy the right tool the first time and if it lasts a lifetime, it is the best deal you could buy. Back in the day, I was happy to buy the large pliers type for $150 in the pawn shop, this is a way better crimper.

Every connection has resistance, resistance will cause heat. In the case of soldered lugs, the heat can cause the solder to melt and the cable to come out of the lug. Nevermind the voltage drop created due to the resistance.

The hydraulic crimper will crimp tight, there will not be oxidation of the connection and the strands are cold welded due to the pressure.

In you example above, if you voltage drop across a connection and are seeing over 0.5V, then you have excessive resistance. It may not be the gauge of wire at fault but rather the resistance of the connection.

For the 2400W inverter in my truck backseat, I ran 2/0 cable, however the length is well over 15 feet. Find a good DC calculator to determine wire size, there is one in the resources section here.

I have just 6 feet of 2ga set for the inverter. It isn't any where near .5v drop more like .05 up to maybe .10v when the battery is really getting taxed hard.
I have a special crimper for my Anderson power Poles. If your familiar with those. It's the only way really. When i solder lugs I crimp them the best I can with some old kliens.

I am an EE and worked in an automotive OEM production environment for awhile including EV. Always crimp. Its a much better joint. The secret is to buy quality crimp connectors and a quality crimper that uses actual AWG dies and not metric dies if you are using AWG size crimp connectors.

My large crimpers are Greenlee and they were over $300 but the one that this guy talks about is a good one:

Making Your Own Battery Cables - Marine How To

Pick Your Crimp Tool FTZ 94284 & Ancor Hammer Crimper TEMCO TH0005 & FTZ Bench Mount BUY FTZ 94284 CRIMP TOOL - BAY MARINE

marinehowto.com

FTZ Correct Crimp Heavy Duty Lug Crimp Tool

FTZ Correct Crimp Heavy Duty Lug Crimp Tool PN 94284 Crimps to UL specifications (when properly calibrated)

baymarinesupply.com

This is an excellent description how to crimp small wires. I actually bought his tool while he was still selling
it.

Marine Wire Termination - Marine How To

Marine Wire Termination - Tools of the Trade MHT Recommended Tools: The products below are our top picks for crimp tools. RecommendationsI include; PRO GRADE, MARINE GRADE, & PENNY SAVER GRADE. Every tool recommended BELOW, we have tested here.

marinehowto.com

I buy all my crimp connectors from here. They used be genuinedealz and had free shipping. They now charge for shipping so I buy more at a time to make it worth it.

Custom Cable and Wire | Marine Grade Cable and Wire Products

Custom Cable and Wire is home to custom made battery cables and the best quality US made UL 1426 marine grade wire products for your boat, rv, trailer, auto, solar, atv needs. Next day shipping available on most orders.s

www.customcableusa.com

For small wires, this is the tool I used to use. When I bought it from the Marinehowtosite, it was only $130. Trying to find where you can get it cheaper for friends that are lookig.

Heat Shrink, Solder Sleeve Ratchet Crimp Tool - 24-10 Gauge

This ratchet crimp tool is specifically designed for crimping 24-10 gauge heat shrink, nylon and vinyl insulated terminals. The ratchet release prevents insulation damage on your terminals.

www.delcity.net

My motto is crimp when you can...solder when you have to. For anything bigger that 10AWG....always crimp.

For amateur radio , We crimp the Anderson 30amp power Poles. The actual Anderson crimper is around 300 but powerworx make a $50 one that's awesome with different dies you can swap. I just bought mine from hamradio outlet with 30 power pole pairs for like $79 and use it on every ham radio related power cord. I'm going to see if my old boss has a hydraulic crimper. I think he does. He sells batteries and has small auto repair shop.