diy solar

diy solar

To solder or not to solder?

Cable stripping tool.
Watch the video they link in the ad
 
First I want to know if you wanted tinned wire or not.
At this point IDK. I am exhausted trying to figure all this out. Not getting enough sleep studying all this. I think I was following what @JeepHammer said, but I don't know anything at this point :-/ thanks
 
At this point IDK. I am exhausted trying to figure all this out. Not getting enough sleep studying all this. I think I was following what @JeepHammer said, but I don't know anything at this point :-/ thanks
Gotcha.

Relax.

Jeephammer is impressively skilled.

Tinned wire is EXPENSIVE but it is the best.
I HIGHLY doubt you would ever ever ever need tinned wire if you are crimping your own cables, crimping the lugs, soldering the crimps, and glue heat shrinking them also...

I think your list is fine as is, I just didnt want you to order it, if you were expecting tinned wire.
 
Gotcha.

Relax.

Jeephammer is impressively skilled.

Tinned wire is EXPENSIVE but it is the best.
I HIGHLY doubt you would ever ever ever need tinned wire if you are crimping your own cables, crimping the lugs, soldering the crimps, and glue heat shrinking them also...

I think your list is fine as is, I just didnt want you to order it, if you were expecting tinned wire.
Thank you.
 
Source, Battery, Charge Controller, Panels, etc.
Fuse/breaker as close as practical to Source.
Wire/Cable that will conduct MAXIMUM load (inverter/lights/whatever)


Oversized circuit protection, or undersize wire/cable is dangerous.
Undersized cables will 'Starve' the load and heat up,
With an Oversize fuse/breaker the wire/cable can get VERY hot and the protection won't activate.

Fuses/Breakers are used in TWO different ways,
1. To protect wires/cables when they fail. (Damage, corrosion, etc.)
2. To protect a specific appliance from excessive load draw.

The fuse/breaker heats up first and blows/trips BEFORE the cable heats up and melts insulation, start fires on the wires/cables, and are *Usually* sized a little big, or 'Slow Blowing' to allow momentary over demands to pass without blowing/tripping.

The device protection (fuse/breaker) is sized MUCH closer to the operational load the device is *Supposed* to demand.
There is a reason so many devices come with their own circuit protection that can occasionally burn/trip, and the reason is they are sized specifically to protect the device and not protect the main line.

------------

SO!
Now you have a battery/batteries of 1,000 amps,
Now you have cables capable of 200 amp supply to inverter,
Now you have circuit protection, say a fuse at the battery to cable connection that will melt at 220 amps if the cables are dead short circuited together...

You have a sharp edge rub through the insulation and contact something that's chassis 'Grounded',
Something like sheet metal that only takes 30 amps to melt into molten slag, orange hot pools of liquid metal...
TWO things are going to happen fairly quickly,

The first is the 220 Amp fuse IS NOT going to burn and disconnect the batteries from the cable.
The 30 amps required to melt thin steel into puddles is not going to trip a 220 Amp protection device.
60 amps will melt/weld 2 pieces of 1/4" steel AND the welding rod, and still not trip the circuit protection.
The 'Smart' money is spent on insulation & armor for the battery cables ANYWHERE they touch anything that can damage insulation.

The second thing that's going to happen is you will have orange/yellow hot ball of molten metal dropping on anything under them.

Hopefully you have a $15 smoke detector stuck right above your primary wiring!

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Watts ÷ Amps = Volts
Watts ÷ Volts = Amps
Amps x Volts = Watts
Volts x Amps = Watts
This is a constant.

The LOAD determines how many Amps gets dragged through any given wire/cable/terminals/connection points.

1,000 Watt Load, powered by a 12 volt battery/batteries in parallel,
1,000 Watts ÷ 12 Volts = 83.33 (84) Amps.
Discounting any resistance from terminal ends, stacking terminals, etc
That's a 4 Ga. Wire size minimum to conduct that 84 Amps,
4 Ga wire will conduct 92.3 Amps
(Always round UP and size UP)

I use the Brown & Sharpe scale, once I find amperage, I simply look up the amp load (rounded up) and then see what wire gauge size handles the amperage.
This is the scale the American Wire Gauge is based on, adopted almost directly.
Find your amperage in the 'Amps' column, follow far left for wire size.

View attachment 2327

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Everyone will do what's best for them...

I personally won't mount something with high amperage directly on anything flammable.
While plywood is an electrical insulator, the glue & wood are flammable.

A small piece of sheet metal from the hardware store behind the inverter, charge controller, etc is a heat shield/fire retardant.
For the DIY types that scrounge, stoves, fridge/freezers, washers/dryers, anything made of sheet metal that's handy will donate.
Another source is stove pipe that snaps together (steel or aluminum).

I keep anything flammable to a minimum in my unattended solar/machine room.
I've seen big truck battery cables melt through the heat treated frame, battery cables melt through angle iron battery racks, etc.
Nothing to catch fire, so the things I saw didn't burn completely down, or they would have been in the junk yard instead of being repaired, but I tried to learn from the experiences...
Rule Number Alpha) The size of your fuse or breaker cannot exceed the amperage rating of the wire. Rule Number Bravo) The size of the load cannot exceed the amperage rating of the fuse or breaker.
 
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We have some weird broken quote brackets going on here. Just hit the report link in the particular post you are talking about.
 
We have some weird broken quote brackets going on here. Just hit the report link in the particular post you are talking about.
OK, some of my emails went to the trash today too, weird stuff thank you
 
So, with all your advice and Will's blueprint I am ordering these TODAY (unless someone tells me otherwise) any place I can find them. I don't want to use Amazon, if possible. I NEED TO GET THIS ORDERED RIGHT AWAY. If you know of a better or faster way or place to get them, PLEASE let me know . I would love recommendations! If I got anything incorrect, please tell me:

1. (Four) 4 of these heavy duty lugs for battery terminals only (I have 2 battleborns) so I need (4) Heavy Duty Lugs. The terminals are 5/16": https://www.electricalhub.com/generic-151-heavy-duty-tin-plated-copper-cable-lugs-17

Good, with the brass bolts these will do fine.
10 gives you some 'Screw-Ups'.


I use the same stuff myself.


Looks fine.

4. 5/16" Brass nuts and bolts at the battery terminals, so I need 4 sets of each. (The Battleborn batteries came with 2 sets of steel nuts and bolts with brass washers. Why did they send me two different sizes (lengths) of bolts?) I looked at Home Depot and didn't see the brass ones. Are these the correct ones to order? https://www.ebay.com/itm/M4-Solid-B...hash=item286f084a6f:m:mTPJec2C1CXSO40fmNljnLQ It looks like they're coming from China though??

They sent you two different lengths because they don't know if you are using thick or thin terminals.
You don't have to wait on brass to mock up or actually use your system, they just help conduct current and reduce resistance.

5. 1/0 ought tinned copper cable for battery to inverter (red and black): https://www.amazon.com/gp/product/B01MD1XRSL/ref=ox_sc_act_title_3?smid=A2TN19FHI2Z5KL&psc=1

Cable & lugs OK, I don't think the heat shrink is glue lined.

6. 4 AGW Tinned copper cable for the rest of the system's cables: https://www.ebay.com/itm/8-6-4-2-1-...ry-Copper-Cable/252712989985?var=551692067407

4 Ga is fine for charge controller, etc.


7. Battery to battery cables for 2 batteries. I forget what gauge to buy at this point. I was going to buy 2AGW?? IS THIS CORRECT?

Nope. Use the 1/0 you use for mains between batteries, you ordered extra and terminals too.


Just fine.


Not familiar, sorry. Get a tube of 'Tune Up' (Dielectric) grease from the auto parts store and full up connectors before FINAL assembly/connection. Seals on connectors always leak over time, grease helps keep moisture out.
If you intend to drive on salt covered roads this is mandatory unless you want to chase endless problems.

8. 250amp Fuse ANL

Should work.


It will 'Work' for larger lugs, but it won't be pretty, and you pretty well need to solder.
Those things like to leave a LOT of strands not captured and it can punch holes in terminals if you don't watch what you are doing.


Keep in mind you CAN pull the insulation off and solder the larger ones, then use your own heat shrink.
I yank a lot of plastic and low grade heat shrink off to make my own crimp/solder connections.
What ever makes the best connection...


Those are low end 'Barrel' connectors, I would solder them so the hole is closed up, and again to seal up the copper from corrosion.

12. Wire stripper tool that will strip the above sizes from 1/0 to 10AWG... any link please?

Anything from a razor knife to the jaws of a cable cutter,
SCORE the insulation, twist & pull.
You don't have to cut into the cable.
If you don't trust yourself, the stripper tools are all about the same, but get one with common replaceable blades.
Some use razor blades, some use utility knife blades.

13. Can you recommend a link for the correct Armor? There are so MANY different types at Home Depot...any link?

If the batteries are going to be inside with you, just use rubber hose anywhere cables rub.
If they are going to be outside living quarters (BBs won't charge below 32°F) use hydraulic pressure hose.
It's steel braid reinforced and virtually impossible to destroy.
It's also smooth rubber/plastic lined.

14. Two Battery boxes or one large one that holds two batteries if that's possible? Recommendations? Can you put 2 in a box? I saw someone use a large Tupperware box?

Two in a box is fine. Insulated box if it's going to be outside.
The idea of a box is to contain battery 'goop' and the lid protects terminals.
I would use a belt/strap to tie the battery box down since it's mobile.
Accidents DO happen, and one strap keeps the batteries in place so they don't short out.
 
The only stupid question is the one that was unasked. We were all beginners once. So, no problem here. Ask away.

My belief is you CAN NOT ask a 'stupid' question.
(But you can get a LOT of stupid answers...)

Ignorance is simply a lack of education in any particular subject.
So ANY relevant question, by definition, can't be 'Stupid', just ignorant.
(and that's NOT an insult since it's the definition)

Education cures ignorance, so ASK AWAY!

-----------

Not much anyone can do about 'Stupid'.

Stupid is knowing the difference but doing the wrong thing anyway.
Seek a doctor's advise, then ignore it.
Seek a lawyer's advice, then ignore it.
Seek electrical advise, then ignore it.

--------

I didn't know what it was called until a few years ago, not sure it had an 'Official' name...
'Armchair Quarterback', 'Keyboard Commando', 'Internet Expert', 'YouTube Degree' come to mind.

The guys that got an 'Education' from books/videos and never really did anything in the real world, don't understand 'Shit Happens!' and you MUST be prepared for shit to happen...
Absloute confidence in their abilities, a god like belief they are 'Right' and everyone else is an 'Idiot'.

Absloute CONFIDENCE, very little COMPETENCE....

Dunning Kruger Chart.jpg

I tell out right, up front, this is the best way *I* have found in the last 40-50 years,
I'll let *YOU* decide if you believe it or not.
There might be a 'Better Way', but then you have to decide if the cost/benefit is correct for your application.

I provide basic, solid information (amp load/wire gauge charts for example) and reasoning for my way of doing things...
You decide what you think is best for your application.

I'll provide information where *I* screwed up/had failures, and how *I* overcame those issues,
*You* decide if your builds won't suffer the same fate...

---------

*IN MY OPINION*...
You NEED to learn to make good, solid crimps, and own good crimping tools.
You NEED to learn basic soldering skills.
You NEED to learn how to read and draw basic diagrams, if not read/draw electrical schematics.
You NEED to learn how electrical circuits work, that it all begins with Load/Demand and work backwards from there... Not from the battery forward...

Books teach you 'Theory',
Application (Doing) is the other half of 'Education'.
Competence comes from Education (BOTH of the above).

We all know the person that can spout sports statistics endlessly, but how many are actually talented (collage) amateur or professional players?

And I know all too well that people can do things 'Wrong' all their lives! (Use me as the poster boy)
I'm living proof, I have an 'Idea' of how *I* think it works/what's 'Needed', and then someone comes along and shows me a better way,
From little 'Tips' & 'Tricks', to great big 'Holy Shit!' game changer ideas...
Leave your ego out of it and recognize a good idea when you 'Steal It'! ;)

The question of this thread was to solder or not in large cable/lug applications.
When in doubt, and the application will accept it, SOLDER.
It 'Hurts' nothing, and it can help in so many ways...
And it's just too easy to learn/do in practice.

Arguing AGAINST something that has worked for more than a century, is done in all industrial applications that have lasted a century, and science is still spending time & money refining because it works so well, is argument & time wasted.

*I* am not a scientist, I can't tell you what molecular research advances are being made,
I know what HAS worked, still works, and is reasonably easy for amateurs to do passably well to remarkably well.
*I'm* not building anything for a NASA mission to the moon or Mars,
I'm building wiring harness that survive what accidents/screw-ups/contamination-pollution we deal with right now...

If my solar power system makes it to Mars, something went REALLY WRONG in 'Back-water' Indiana right here on Earth! ;)
I use what's common & available, and make the best of it...
 
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If you crimp, put a zinc based antioxidant inside the crimp before you do it. It'll squeeze out of the way of the direct copper-to-copper contact and the zinc will help whatever is not making contact conduct. Furthermore it'll keep oxygen and moisture from degrading the copper-to-copper contact. I personally use a product called "Noalox"

Having said that 10ish years ago I personally have had 4 gauge wire melt at a crimped contact in my first battery bank, it didnt have any compound in the crimps and almost all the contacts were so corroded they broke off in my hand when I checked them. Scary as hell. This was with untinned wire that the lugs were crimped with a vise grip (the absolute worst way to crimp a battery cable) and I used electrical tape to cover the lug/cable join.
Every single thing I did there was wrong.

In that same battery bank I had 6 cable-to-lug connectors that I had soldered instead of crimping. None of those showed any degradation at all other than some corrosion on the cable itself. I went from soldering to crimping because it was taking so damn long to solder them and I had a lot of connectors to do.

IMO if you crimp PROPERLY with a hydraulic crimper with the right die size and antioxidant compound its as good and long lasting as a soldered connection. If its anything less than that you stand a decent chance of the connection going bad over time.

The best wire to use is tinned copper cable, that stuff is immortal, but it's expensive. A tinned wire to a tinned connector crimp even without compound will almost always last for decades at least. Never use untinned lugs.

I never, ever EVER recommend screw connectors for high amperage connections.

If you just talking about 12 AWG or smaller low amperage cables a standard hand crimp with compound in the crimp will be fine.

Soldering tip: if you wrap a doubled/tripled up strip of wet paper towel around the exposed copper of the cable it'll help a lot to keep the solder from wicking up the cable strands. If it's bigger than 10 AWG you're going to need one of those small butane torches, big 1/0 or larger you'll need a propane torch. Use plenty of heat and make sure the solder has flux in it. If it doesnt have flux add it with a little brush before you solder, a bad solder join us almost universally because you didnt use enough heat, or enough flux, or both.

Bottom line, if you dont have a real crimper, crimp it down with a vise grips and then solder it. You need to have a decent mechanical connection in place before soldering a wire of any size. After you solder it cover it with heatshrink, if you're in a marine or corrosive environment use the heatshrink with the glue inside.

In my lifetime I have done a truly stupid number of wire-to-lug and wire-to-wire connections. I've never, not even once, had a soldered connection go bad - even when I did a crappy globby soldering job.
Noalox is great stuff!
 
This will drive y'all bonkers: If I want the best connection, I tin my clean copper cable and dip the end in soldering paste, (aka flux), then slide the tinned copper wire into a clean crimp lug, crimp the lug, then heat up the lug and wire and when both are sufficiently hot, I apply solder to the work and let it flow. The solder on the tinned cable melts, further improving the bond. THEN, I slide the proper sized, high quality, piece of heavy duty, glue impregnated heat shrink over the connection and shrink it using a hot air gun.
 
This will drive y'all bonkers: If I want the best connection, I tin my clean copper cable and dip the end in soldering paste, (aka flux), then slide the tinned copper wire into a clean crimp lug, crimp the lug, then heat up the lug and wire and when both are sufficiently hot, I apply solder to the work and let it flow. The solder on the tinned cable melts, further improving the bond. THEN, I slide the proper sized, high quality, piece of heavy duty, glue impregnated heat shrink over the connection and shrink it using a hot air gun.

I'm not sure I would do things that way...

Tinning a bundle, then re-melting for the lug solder is double melting, which I find to be more difficult to do correctly than a single melt, particularly with solid core solder (no mention of rosin core solder).
Some people don't have an issue with it, but I find I get separations/lamination layers when I try to double melt...
Might be I always use rosin core solder on common electrical connections...

I generally tin once, after the lug is crimped on, to the insulation line, and stop.
Only the outside of the wire/cable needs tinned, so I don't saturate the wire unless it's going into a screw compression connector.
Just my way of doing things, if you have better ideas I'd sure like to hear them...
 
I'm not sure I would do things that way...

Tinning a bundle, then re-melting for the lug solder is double melting, which I find to be more difficult to do correctly than a single melt, particularly with solid core solder (no mention of rosin core solder).
Some people don't have an issue with it, but I find I get separations/lamination layers when I try to double melt...
Might be I always use rosin core solder on common electrical connections...

I generally tin once, after the lug is crimped on, to the insulation line, and stop.
Only the outside of the wire/cable needs tinned, so I don't saturate the wire unless it's going into a screw compression connector.
Just my way of doing things, if you have better ideas I'd sure like to hear them...
You already heard my better idea, but, what really matters most is to use the effective and safe method that you prefer and are most comfortable with even if it's just plain crimping without any solder, which works fine with quality connectors and crimpers.
 
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Sorry for the confusion. Santa's happy ;-) Thank you.
I notice that when I reply to a post, the body of the past that I am replying to is included in my reply. I also notice the same inclusions when others reply to posts so I thought it was normal. The copy and paste function is not something that i choose to do, it just does it automatically.
 
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