Vendor sent me the wrong battery cut-off "Kill Switch", but...
All modern electrical systems require some kind of "Master Kill Switch" in order to isolate the main power source from the rest of the system.
This is done primarily for safety; that is, personal protection from inadvertent electrical shock during emergency repairs, as well as during routine maintenance of the system.
A Master Kill Switch can also prevent your precious and expensive electrical devices from becoming a pile of burnt toast.
Sudden surges of power can easily overcome under-sized circuit breakers and poorly chosen or badly installed fuses.
When I say "poorly chosen or badly installed fuses", what I really mean is that the chosen fuse is not rated to protect the electrical wire that it was installed to protect; or maybe the fuse is situated far from the source of power instead of the recommended eight inches or less.
Of course, this is also "ass-uming" that the appropriate gauge and type of wire or cable was chosen in the first place.
But let's face it.
(Warning: Necessary Side-Bar Incoming.)
Even the most thoroughly researched, expertly designed, meticulously built and never run near max load systems have become heaps of smoldering, very expensive, paper weight blobs in the blink of an eye.
Sadly, 99% of the time, the cause is this: "Cheap, Sub-Par, Knock-Off or No-Name products and materials".
You know what I'm talking about.
It's the products that graciously provide you with a "user manual" and/or spec sheet that's hardly bigger than a matchbook.
(.. And discovering that my reading glasses are useless with the itsy-bitsy print, I break out my phone's "Magnifying Glass" app. Then...Uh-hum...yeah, there sure is quite a bit of information in that little "Cracker Jack" surprise-sized "user manual". Too bad it's all in Mandarin or Cantonese! And of course, "I don't sprechen that one.")
Heavy Sigh.
Anyway, a little advice: "NEVER SKIMP ON YOUR SYSTEM'S WIRES AND BATTERY CABLES. "
Trust me, saving a few bucks by using "just enough to handle the load", smaller gauge or cheaper electrical wire is not a wise move.
If you buy AWG 8 when the load really requires AWG 6 or AWG 4 - to account for a good 25% margin of safety; or opting to use Copper Clad Aluminum vs. Multi-Stranded, Tinned Copper with high-rated outer insulation, it will only lead to a bunch of headaches for you later on.
After a couple random operational hiccups, the paranoia begins to settle in.
You wonder if your thriftiness did nothing but create an unpredictable, "Train wreck waiting to happen" system ("...to fondly call your own? Not!").
You may encounter a slew of hard to diagnose, "electrical black holes", dead zones where there should be power!
You witness strange, "totally illogical" short circuits, reverse current and snail's pace - if at all, solar charging.
What will you do when - all of a sudden, your electrical wires seem to desperately crave fire and smoke?
Ready to deal with uber-aggravating and repeated "nuisance tripping" of your demon-possessed circuit breaker(s)?
(...And deftly making a bold cross with the red and black probes of my multi-meter, I bravely faced the un-Holy device and shouted, "The Power of Christ compels you!...")
But the one "Electrical Aw $hit" that makes me shake my head and pity the poor, frustrated victim is a case of the "FIBIFIBIFIBI! Inverter Syndrome" - pronounced fib-ee-fib-ee-fib-ee and stands for "Fry It-Buy It-Fry It-Buy it-Fry It-Buy It!" Inverter Syndrome.
(End of my Aside. Thank you very much for your patience.)
Back on topic:
A Master Kill Switch for my 12V 280Ah LifePo4 battery that gets power from my solar panels via a 100A charge controller; then the battery powers the 2000W DC to AC inverter to run my fish tanks and SBC mining rigs.
For my Kill Switch, I chose the simplest, inexpensive, difficult for manufacturers to fake and virtually impossible for DIY electrical hobbyists (like myself) to screw up.
Just secure it to your battery terminal and Presto! You now have a "Just Turn the Dial" Kill Switch.
Turning the dial Counter-Clockwise disengages (or turns "OFF") the battery and turning it Clockwise closes the circuit and turns "ON" the battery.
Easy-Peasy, no?
Well. Actually, no!
The stars must not have been aligned.
Maybe I unknowingly pissed off some ancient Druid Deity when I got rid of that dead tree in my backyard? It was done at midnight, preceded by the secret 5,000 y/o ritualistic dance. In keeping with tradition, I wore the ubiquitous "sacred red thong" - only that and nothing else.
Wait a minute, please...
Experiencing a vivid flashback.
("Sweet!")
Okay, back to the story.
Because of some glitch in the supply chain - or possibly, the work of a cabal of disgruntled midget employees, still sore over their "pitiful" 35% annual wage increase and being denied, "The ergonomic (aka "lowered") working conditions that every Little Person in America deserves!"
Whatever the reason, the point is that I didn't get what I ordered.
(Boo! Hiss! Boo! Hiss!)
I received this big, ugly and heavy "thing" instead.
This device appears to be for a van or bus battery and definitely was not made to fit the M8 terminal bolt of my LifePo4 battery.
(The Hook! Send in the Hook! Or else we start throwing rotten cabbages!...)
I immediately notified the shopping platform plus the vendor of the wrong item delivery and that I wished to return it for a full refund.
When they said I'd get a "store credit" instead of a refund, I got a little angry.
But since I paid cash (COD) and didn't have an account from a bank they could transact with, the only thing they could do for me was an instantly redeemable store credit in the amount of my original order - already in the balance of my brand new in-store "wallet".
Imagine that?
Additionally, they DID NOT REQUIRE ME TO RETURN THE WRONG ITEM. Hmm, interesting....
I searched the site for another battery cutoff "Kill Switch" similar to the one I originally ordered, but all of them were now listed as "Out of Stock". WTF?!
But wait...
Shortly before another spike in blood pressure, then those scary, pulsating veins on my temples, I got a DM from another vendor stating that his version of what I wanted was on sale for half the price of his competitor's "Out of Stock" product.
They two battery cut-off "Kill Switches" were structurally and functionally identical. The only difference was the blue color instead of black and the 50% cheaper price. ("Sweet!")
I promptly ordered two blue battery cut-off "Kill Switches" and still didn't spend all of my in-store credit.
(Yay!)
Oh, and about that item I didn't have to return? I turned it into an exotic-looking, Mega Bus Bar. It can easily double as a solid 400+Amp Terminal Extension.
Features include:
Four connection sites, stainless steel M6 and M8 Phillip's head bolt, nut, washer and lock washer assemblies, M8 to M10 sleeve adapter and the ever-so-popular "Just Turn the Dial" Kill Switch.
("Very Sweet!")
Submitted FYI.
May you and yours be well and loving life today.
In Lak'ech,
JaiChai