Electric System Problems

[whoaru99]

Yeah... you'd never want to use acid flux, per se, on wiring connections.

There are many different fluxes available and 60/40 or 63/37 general electrical/electronics solder types with varying degrees of flux agressiveness and some "no clean" varieties that many still clean.

Well off on a tangent now...

 

[Broken Crow]

If I absolutely had to solder a high-current connection, I'd use the quad-eutectic solder and rosin from Cardas...Hey: It's made in the USA so there's no iffy chemistry or metallurg.....I don't usually solder crimps though when I have the properly spec'd crimping parts to hand.....just sayin'

https://www.cardas.com/supplies

 

[KyBeer]

In my job before retirement I worked with 120Kv and 700 amp equipment. All the connections mechanical. The connectors and wire were rated 200% of the expected load. Tried to carry that practice into the build of my brew system. If 10 awg was the minium gage then 8 awg is what I tried to use.

 

[whoaru99]

I don't oversize simply for oversize sake but if all I have is oversize I'll use it, so long as it's not too cumbersome or impractical to use it.

 

[KyBeer]

Has anyone measured a heating coil resistance to ground? I posted a picture of my damaged / weak element. I over heated the element by selecting the wrong kettle. By the time I could smell the heat the element was red hot. I let it cool and the next brew was a small 5 gallon beer and it seemed to be fine. The next beer required a 12 gallon boil. It only made it to 200 degrees. I suspected the element was damaged. I replaced the burned connecters and cutback the cable a bit. Same results.
I ordered a new element. I always chek the resistance prior to installation. Both elements measure about 10 ohms as expected. A check of the element to the ground on the old element show open as it should. The new element measures like a cap. It starts around 18 meg and climbs.
Strange!

 

[Broken Crow]

I suspected the element was damaged. I replaced the burned connecters and cutback the cable a bit. Same results.

Heck.. never mind the connectors, nichrome connection to the terminal is compromised;

 

[KyBeer]

Heck.. never mind the connectors, nichrome connection to the terminal is compromised;
View attachment 879111

And that is why I repplaced the element!

 

[hungupdown]

I suggest the heat discoloration could be two fold.

The terminal hole size is too big relative to the screw size, and it's possible the crimp of the terminal on the wires themselves is not a good, high compression crimp.

If the crimp terminal was copper, it should have at least the same cross sectional area as the cable connected.
But often it seems to be much less.
And as terminals are usually tin plated steel, the cross sectional area actually needs to be bigger.

 

[whoaru99]

Personally, I don't run into too many steel terminals other than in some cases where they are uninsulated, nickel-plated steel for high temp use.

The nice thing about using big names like Molex et al is if you dig enough one can usually find detail datasheets that give current ratings for the various styles and sizes.

 

[sibelman]

Replacement lugs: NSI branded 8AWG Short Barrel Copper Compression Lug with Peep Hole #10 Bolt Size

 

[whoaru99]

Ahhh, for the bigger lugs I use a hydraulic crimper setup.

 

[sibelman]

Ahhh, for the bigger lugs I use a hydraulic crimper setup.

Yet another reason to solder

 

[doug293cz]

Ahhh, for the bigger lugs I use a hydraulic crimper setup.

At what wire gauge do you switch over to hydraulic crimping?

Brew on

 

[whoaru99]

G

At what wire gauge do you switch over to hydraulic crimping?

Brew on

Greater than 10 since 10-12 insulated terminals are the largest rated size for the full cycle crimpers I have.

Last project for the hydraulic crimper was 6ga for 210Ah battery I assembled from "lithium" prismatic cells. These are uninsulated terminals but heat shrinked over the barrels and a bit over the cable jacket.

 

[KyBeer]

Replaced the element and a test boil of 12 gallons of water worked just fine!

 

[sibelman]

Before: poor crimps

After: solid solder joints