diy solar

diy solar

For the best connection I solder, do you? Why not?

molded ends
Molded, soldered, semantics.

Its a soft metal that melts at a lower temperature than the wire used to join the connection.

If you want to tear apart my post, then go list all the different "solders" you could possibly use and grade them...

Silver, gold, heck, the list could go on and on.....
 
Molded, soldered, semantics.

Its a soft metal that melts at a lower temperature than the wire used to join the connection.

If you want to tear apart my post, then go list all the different "solders" you could possibly use and grade them...

Silver, gold, heck, the list could go on and on.....
sometimes you just gotta… solder on ?
 
The rule is: an electrical connection has four critical elements; sufficient mechanical connection; excellent electrical conduction, and environmental protection. The fourth would be cross-arc insulation which #3 creates.

proper #1 should guarantee #2

If I solder like for a fuel injection wire, I only solder after crimping; solder is useful for buried or remote low current applications but solder only breaks the rule of mechanical connection- and you want the unexpected bad thing to survive long enough to blow the fuse, not wait until a fire starts and maybe blow the fuse
Laymans terms and common sense:
- (mechanical connection) make sure wire touched
- (electrical conduction) use material electricity can pass through
- (environmental protection) protect the junction from like water: think - junction boxes, conduit, quality crimp connector, electrical tape, etc We used them all in a crunch.
- (cross arc insulation) Ive had this happen which is why Im not a fan of fuses. Of course use them but a strong surge will jump (arc) a fuse easy. Buried in sand is what stopped mine with a drop to lesser quality conduction. Is exactly what a fuse is where fuse encasement is meant to contain arc.

Think. How far apart would u put a paper cup from a burning tree? Same concept. In event of hefty surge, u want it pass through connection or not? Its going to fry whatever stops it btw.

Proper soldering would not break connection.

I do not want the 'unexpected bad thing' to survive. Also proper preparation the 'unexpected bad thing' wouldnt catch on fire.

Electrical soldering is nothing like plumbing, etc soldering. Different purpose. IE) crimp an hvac, fuel, etc tubing is u gotta be joking. Constrains flow.

Conduction is crucial. Concept is its just an added protection. Thats all.
 
Molded, soldered, semantics.

Its a soft metal that melts at a lower temperature than the wire used to join the connection.

If you want to tear apart my post, then go list all the different "solders" you could possibly use and grade them...

Silver, gold, heck, the list could go on and on.....
Molded and soldered are entirely different things. Though technically you would call it "cast" but whatever. That's close enough to call it semantics. But cast/molded vs soldered is not. We are an injection molding facility so molding it is.

Soldering introduces another material into the connection. Molding the stuff onto the wire with lead is functionally similar to a crimp in that the wire ONLY contacts the lug material. It also does not create the rigid interface between the lug and wire strands that lead to mechanical failure in automotive environments (vibration).

The downside is you don't get full compression that you'd have with a crimp, but this can be done with a secondary operation to compress the lead cast. Some places just do this instead of casting it onto the wire.

It's not semantics, it's a critically important distinction.

Source: we used to manufacture these things before eliminating lead in our facility.
 
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If the load is still drawing 250 amps and the connector is dissipating 50 amp, won't that add up to a fuse pop? Won't there be a runaway causing the load to increase? However, I guess you are still right in that it is possible for it to get hot enough to cause problems without a fuse popping. Thanks for the correction and information.
A 250a fused circuit can do that to a bad lug even if the total load is only 50 amps at the time.

At 200a the lug would probably wind up melting itself if it were that bad, and the fuse still wouldn't blow.

Mind you, this situation is incredibly unlikely. The high resistance of the lug would increase current substantially on its own, it's unlikely to be THAT bad of a connection, and it probably would blow the fuse before the user's load gets that high but there is a grey area in between.
 
Proper soldering would not break connection.

I do not want the 'unexpected bad thing' to survive. Also proper preparation the 'unexpected bad thing' wouldnt catch on fir…Conduction is crucial. Concept is its just an added protection
I disagree. And ABYC does not support your position.

Why would you not prefer a fuse to blow VS a soldered connector melting?!

The mantra, “fuses are to protect the wire” comes from the mindset (and various codes) to let things survive “the unexpected bad thing.”

If a crimp is sufficient, adding solder may sometimes be desirable- perhaps even an improvement. If a crimp is sufficient, solder alone is not. Solder is not a mechanical connection. Look at ANY household wiring, light fixture, etc. No solder-only connections, all mechanical in one way or another

If all it took for safety was preparation we could save a bunch of money on breakers and fuses.
 
I disagree. And ABYC does not support your position.

Why would you not prefer a fuse to blow VS a soldered connector melting?!

The mantra, “fuses are to protect the wire” comes from the mindset (and various codes) to let things survive “the unexpected bad thing.”

If a crimp is sufficient, adding solder may sometimes be desirable- perhaps even an improvement. If a crimp is sufficient, solder alone is not. Solder is not a mechanical connection. Look at ANY household wiring, light fixture, etc. No solder-only connections, all mechanical in one way or another

If all it took for safety was preparation we could save a bunch of money on breakers and fuses.
Pretty much every termination standard I have ever seen explicitly forbids solder as well.

Barring pcb connections for electronics and stuff of course.
 
The amount of incorrect information in this thread astounds me...

It really needs to be wiped off simply because of that alone.... The reason I come to forums is to gain information....

I learned to play a instrument when I was wrong. My teacher told me if you practice wrong all day long all you've done is learn to do it wrong really well. While maybe NOT always true, its true enough.

In talking about this, if you really wanted to go deep, crimping is far far far cheaper with less toxicity than soldering. This probably plays a role in it being more prevalent. The "new" solders since lead was almost completely banned are somewhat "new" and leave many unknowns. At the very least "cycling" is a factor in a soldered connection. I suspect the best connection are crimped and then soldered to be honest.

Using a flame to "braze" is considered soldering.... Thinking it means one thing, a terminal connected using only a certain "solder" is not right.

Even glass can be "soldered"...

Thats reality.

I stand by that which ever one you do best is probably the route you should go. If you suck at both (or don't feel confident) just buy pre made cables.
 
You say that there is wrong information but I don't see you providing examples with sources.

I will agree somewhat with your soldering vs brazing statement, as that's really a matter of temperature over anything else that defines them.

Your stated logic for why crimps are used instead of soldering is also objectively false. It's not about saving money or worker toxicity.

If it was about toxicity, you wouldn't have whole factories running wave soldering machines with gallons of hot liquid solder constantly flowing.

If it was about money you wouldn't see strict engineering standards which outright forbid the practice citing mechanical failure as the chief reason.

Further to the point about the quality of a soldered joint, solder has much higher electrical resistance than copper does. It's inherently worse than a good crimp for that alone.

Please provide your evidence.

Here's mine:
EN 16602-70-26 (crimping of high reliability electrical connections for spacecraft)

A literal NASA document.
First line:
"Crimping is an efficient and highly reliable method to assemble and terminate conductors, and typically provides a stronger, more reliable termination method than that achieved by soldering."

Interestingly it also forbids crimping tinned wires, which is the only place I've seen that, though it might be in other documents and I've missed it.


NEC allows soldering in *some* circumstances and forbids it in others. When it does mention anything about why, iirc, it's again for mechanical reasons.
 
I stand by that which ever one you do best is probably the route you should go. If you suck at both (or don't feel confident) just buy pre made cables.
To this point I'll only repeat that a good solder joint will still be better than a terrible crimp, and I agree that if you can make a good solder joint but don't have the right crimp tools - solder it.
 
I have done both ways but I think crimping requires less skill to get good bond (after crimp tug on connector to make sure no play) vs solder which might be cold joint and not notice until later on.
Solder needs wire and connector to be free of oxidation for the solder to stick. Without mechanical bond the old 60/40 needed to make sure nothing moved until solder flipped from liquid to solid as it cooled. Then clean off the flux etc.
No experience with lead free solders as I still use 63/37 for my electronic work. (30 years habits )
 
Soldering generally creates a superior electrical connection than only crimping.

First coat the end of the wire in flux then tin it with solder.

Then, crimp the connector on to the tinned wire, apply more flux paste and heat the connector and wire works until the work is hot enough to melt and flow the solder, thus creating a complete and thorough bond between connector and wire.
DO NOT rely on the tip of the soldering iron or flame to melt the solder because that creates a cold solder joint which is a bad thing.

Up to a certain point, the bigger the wire and connector the hotter the heat source including in some cases a propane torch.

YES, industrial high quality ratcheting crimp tools and crimps are awesome especially on larger than 6 gauge wire and especially if they contain an anti corrosive/waterproofing sealant.

I'm sure that there are applications when crimping is more appropriate and/or practical then soldering, but number 6 wire is quite solder able.

Never use acid core solder on electronics.

Thank you all for chiming in!

OG
 

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This thread has gotten beyond hilarious. Seriously folks... the discussion is about crimping, soldering or whatever.

However a person decides is like whatever its ur decision. Like seriously attacking folks saying U R WRONG then to quote what the person views as a high profile organization... like geez crimping, soldering, tie a string.

Hilarious. Note: some of us were begged by many groups after publications. Most of us end up leaving for the research world. And many like myself, end up like Dr Su (CEO of AMD), whom is also EE, move into the financial world.

So u come across an interesting topic forum concerning an area uve decided to check out for whatever reason.

And bam, its like college again with all the chest pounding, arrogant dictating concept... big joke but true was many many switch to biz majors.

Can u see the trees thru the forest? Meaning ppl have their reasons for whatever they choose to do.

I stand by my determination that red and blue are equal colors. I prefer the combo, purple. Afterall, purple is the best color CUZ I SAY SO. LOL
 
OK, how about some practical advice for my upcoming activity? I have 3 types of connections: DC battery, DC solar and AC.

Battery connections:
I'm soon to add extra batteries to my system to double capacity. It will be 2 x 48V 190Ah sealed lead acid banks (4 x 12V in series in each bank).

4kW AIO inverter (230V AC). Max expected DC current draw in operation is ~80A give or take, and half that for each battery.

When I started out I ordered some cables to be made and sent to me. These were really nicely done. But they are much longer than needed now the system is in its final housing and since I am going to reconfigure the battery bank I thought I'd make my own cables so they can be made without excess length.

I have 35mm² welding cable, lugs with holes sized for the various screw terminals, and a small hydraulic crimp tool. 8-tonne is the force rating. Still waiting for my heat shrink to arrive. Presuming I crimp these suckers well, this should suffice?

I hadn't planned to solder anything. I don't have any nice solder at the moment (just some old crap from many years ago) but I do have a solder rework station with both iron and heat blower options if ever I need.

Solar PV connections to inverter:
6mm² cable which is currently just clamped into the inverter's terminal. I'm wondering about putting ferrules onto these. I have ferrules and a ferrule crimp tool. Max working current will be up to ~32A.

230V AC input and output connections:
Like the solar terminals these are simple terminal clamps inside the inverter, just a bit smaller than the solar terminals as the wire gauge isn't as fat. But these terminals are very awkwardly positioned making it difficult to get the wires cleanly inside the terminal clamps. Always seem to end up scrunching a wire in the process. So I was also planning to put ferrules on these as well so they will go inside the terminal clamps more cleanly. Max working current up to ~20A.
 
Hey, not sure what you're asking ys know. U seem to have crimping downpat. Im not familiar with exact names if crimping tools. (Arthritis in hands so have use those connect to bench ones... makes me iffy on connection).

Anyway, seems like u know what ur doing. Btw, that 2 48v 190ah is 2 in series then parallel, correct? Asking cuz is that total 190ah or x 2 for 380ah? I try to keep amps low if possible. Ur packing a wallup...

I wouldnt be highly concerned with 32A. For those a dab of solder in conjunction with clamps might secure but u said ur solder was crappy.

Btw, pv directly into inverter... so ur using a multi correct? (Built in controller). Crappy ports seems be common problem that I too am dealing with. My current work-around is keeping amps low to be able to use a lesser awg wire than I would normally.

So apologies, Im working on exact problem atm. I can say, not a good idea to force the connections. If u can get to the connections, I would dab solder then clamp but once again, gotta trust ur solder. U can tell when its solid. U know that or u wouldnt be asking advice.

Anyway thats my 2 cents. Not an expert. Experienced some major crap, including house burned down, so um Im a bit freaky on solid, trustworthy connections. Ppl laugh cuz I lay and space batteries with welding blankets. Batteries worry me. Pv doesnt much.

Good luck on ur setup. Dont see out if battery amps and the inverter clamping worried me.
 
Hey, not sure what you're asking ys know. U seem to have crimping downpat. Im not familiar with exact names if crimping tools. (Arthritis in hands so have use those connect to bench ones... makes me iffy on connection).

Anyway, seems like u know what ur doing. Btw, that 2 48v 190ah is 2 in series then parallel, correct? Asking cuz is that total 190ah or x 2 for 380ah? I try to keep amps low if possible. Ur packing a wallup...

I wouldnt be highly concerned with 32A. For those a dab of solder in conjunction with clamps might secure but u said ur solder was crappy.

Btw, pv directly into inverter... so ur using a multi correct? (Built in controller). Crappy ports seems be common problem that I too am dealing with. My current work-around is keeping amps low to be able to use a lesser awg wire than I would normally.

So apologies, Im working on exact problem atm. I can say, not a good idea to force the connections. If u can get to the connections, I would dab solder then clamp but once again, gotta trust ur solder. U can tell when its solid. U know that or u wouldnt be asking advice.

Anyway thats my 2 cents. Not an expert. Experienced some major crap, including house burned down, so um Im a bit freaky on solid, trustworthy connections. Ppl laugh cuz I lay and space batteries with welding blankets. Batteries worry me. Pv doesnt much.

Good luck on ur setup. Dont see out if battery amps and the inverter clamping worried me.
Reread my post (do that when long). Sorry bout mistypes. I was reading thinking damn that typo doesnt make sense. Sorry.
 
Btw, that 2 48v 190ah is 2 in series then parallel, correct? Asking cuz is that total 190ah or x 2 for 380ah?
2 parallel banks of (4 x 12V 190Ah in series) to give 380Ah @ 48V. Yep a nominal 18.2kWh for which I have no plans to cycle much. Just for grid outage coverage and to act as ballast for the off-grid load (pool pump) being run with the PV power.

Each bank will have its own HRC fuse in a fuse isolating switch, as well as a higher rated fuse for the combined load. Connections will be via some chunky bus bars. I want to be able to take one bank offline and still operate if needed.

Btw, pv directly into inverter... so ur using a multi correct? (Built in controller).
Yes, an all-in-one off-grid inverter/charge controller. Same basic family as the MPP models you have in the US.

Buggers to get wires into the terminals. Hence I was thinking to put ferrules on to make it easier.

For those a dab of solder in conjunction with clamps might secure but u said ur solder was crappy
Decent solder is only an online shop away...

including house burned down
Ugh, that sucks.
 
I use a 1970's model USMC cable crimper for anything from 8g up to 004 gauge. it has adjustable dies along with (what can I say military) a training manual for Army, USMC, and USN that covers how to adjust and how to calibrate to the wire size, and material being crimped. (there is a difference) this thing was designed for aircraft but can and is still used for electrical work on ships as outlined in the manuals.

anything between 4g 10g and I use a ratcheting hand crimper below that I use a standard crimper. I will solder wires where impedance and corrosion etc are a concern. It all depends upon what you are doing and the environment of where you are using it.
 
This thread has gotten beyond hilarious. Seriously folks... the discussion is about crimping, soldering or whatever.

However a person decides is like whatever its ur decision. Like seriously attacking folks saying U R WRONG then to quote what the person views as a high profile organization... like geez crimping, soldering, tie a string.

Hilarious. Note: some of us were begged by many groups after publications. Most of us end up leaving for the research world. And many like myself, end up like Dr Su (CEO of AMD), whom is also EE, move into the financial world.

So u come across an interesting topic forum concerning an area uve decided to check out for whatever reason.

And bam, its like college again with all the chest pounding, arrogant dictating concept... big joke but true was many many switch to biz majors.

Can u see the trees thru the forest? Meaning ppl have their reasons for whatever they choose to do.

I stand by my determination that red and blue are equal colors. I prefer the combo, purple. Afterall, purple is the best color CUZ I SAY SO. LOL
Well yeah. That's why I will agree that an OK solder job is superior to a garbage crimp.

Doesn't change the fact that it has real consequences, particularly in mobile applications, and crimping is strongly recommended for that reason.

I've been soldering and crimping stuff for 20 years or so. While I understand that does not make me any sort of authority on the subject I can tell you I've had to repair a lot of really good solder joints that break where the wire leaves the lug and crimps just don't do that. Not all at once anyways.

A solder joint is usually good right until it isn't, while a crimp will break a few strands here and there which is easily found by regular inspection.

No amount of money in manufacturing will make a solder joint a superior mechanical connection without additional strain relief.


It might be 15 months or it might be 15 years later but to me a hundred dollars on a crimper for a thousand plus dollar project to have a lower chance of burning my camper down with me in it is well worth the cost.
 
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