diy solar

diy solar

Socket head dropped and sparked, is this a short?

Haha yes someone on youtube should do this in a controlled manner and measure the current going through. Would only cost two cells and some careful setup. Could sacrifice a clamp meter perhaps?

This situation is why I have my ratchets for building banks, covered in duct tape.
Honestly you can just calculate it from a sample measurement.

Tack weld a ratchet to two pieces of aluminum and measure the resistance from one end to the other. Add it to the cell IR and do the math.
 
I did something similar when tightening the negative cable to my inverter - managed to connect the butt end of my socket wrench to the positive! Big spark, hit my head on the top of the battery compartment, may have squealed like a 12-year old girl.
InverterWeld.JPG
 
The US Air Force almost blew up Colorado with a 9 Megaton Thermonuclear warhead because they "dropped a socket"

When the Titan's fuel tanks exploded inside the silo, it sent the 700 ton concrete silo cover high into the air and blew the nuclear war head all the way across the base.

Don't feel bad. It happens.
 
Haha yes someone on youtube should do this in a controlled manner and measure the current going through. Would only cost two cells and some careful setup. Could sacrifice a clamp meter perhaps?

This situation is why I have my ratchets for building banks, covered in duct tape.
Beware, some duct tape is conductive. Learned that the hard way!
 
I bought 1000V insulated ratchet, extension, 10mm socket and 10mm nut driver on Amaz. They are worth it! Especially after blowing molten metal across the dining room during a power outage at 3 AM. I found out real quick that these weren’t your standard, tame, high IR, little lead acid battery!
 
Haha yes someone on youtube should do this in a controlled manner and measure the current going through. Would only cost two cells and some careful setup. Could sacrifice a clamp meter perhaps?

This situation is why I have my ratchets for building banks, covered in duct tape.
I did a short test on a 25ah TopBand cell.


This guy takes it to another level.

 
Of course there's no way of knowing without testing so we're going to need OP to put a hall effect sensor with a really really fast response time on the ratchet and repeat. For science of course.
And put a pair of Depends on PRIOR to the test. Will make clean up much faster.
 
some heat shrink typing and shrink it on the ratchet and the socket extension
is why I have my ratchets for building banks, covered in duct tap
Harbor Fright has fairly decent 72-click ratchets with the handle entirely plastic. I don’t mind them. I don’t know what their voltage rating is, if any.
The price isn’t bad either.

A quote to remember: “9/16 is I think definitely the load of choice for your battery testing”
 
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I have the Harbor Freight "composite" handle ratchets from long before I got into solar stuff. Even absent any possible voltage resistance, I really like them just as ratchets on their own. They take a beating, and not so cold in the hand as metal ratchets.

30% glass fiber reinforced nylon has the same tensile strength as aluminum, so you're not losing much at all.
 
$15 would have saved a lot of worry... Nothing comes near my batteries except this socket wrench. Instead of spending $100 on a composite socket set, I bought a set of regular 1/4" sockets and wrapped them in several layers of good electrical tape. Extensions too. Bought a insulated screwdriver set as well.


 
$15 would have saved a lot of worry... Nothing comes near my batteries except this socket wrench. Instead of spending $100 on a composite socket set, I bought a set of regular 1/4" sockets and wrapped them in several layers of good electrical tape. Extensions too. Bought a insulated screwdriver set as well.


Yeah this thread "sparked" me to order the ratchet this morning
 
Ok I am going to try this. I hope I can explain it properly enough for everyone to understand. I will probably mess it up though but here foes.

When you get a short. The battery can act like a capacitor in that it gives off a lot of or ALL of its power in a short, and of course, very fast burst of energy.
Now as fast as it all is. If it is short enough in time. It can sometimes only give off some or most of its energy but not all.
In that case. It is possible that the battery is just fine. And will only need recharging.

If it gives all or close to all of its charge, then it might be dead or close to it and damaged inside.
The best way to test is to simple charge it up for an hour or so and see if it hold a charge. If it does, then it may very well be fine and you can charge it up fully.

I hope this clears things up for some. :)

I am glad you are ok as well because liquid metal can do some serious damage to flesh.
 
The US Air Force almost blew up Colorado with a 9 Megaton Thermonuclear warhead because they "dropped a socket"

When the Titan's fuel tanks exploded inside the silo, it sent the 700 ton concrete silo cover high into the air and blew the nuclear war head all the way across the base.

Don't feel bad. It happens.
Are you sure it wasn't *this* incident?

 
Are you sure it wasn't *this* incident?

That might be it..

My excuse: I changed the names and places to protect the innocent. LOL

I watched a documentary about it way back, but have long forgot the finer details. Out west, missile in silo, guy drops a socket, punctures fuel tank, boom.. Yup, that sums it up! hehehe..

Nice find! Apparently such events are called a "broken arrow"

As one movie put it:
I'm not sure what concerns me most, that they accidentally blew up a nuclear missile, or that it happens so often they have a name for it...
 
Totally newbie here. I'm building my first battery, 16S48v with Fortune cells. I just top balanced to 3.6v (took two weeks).

I was putting my BMS on, when I dropped the Ratchet. The socket head connected the positive and negative of two batteries, sparks flew and a flame shot up. I grabbed the wrench and pulled it off.

Inspecting the damage, it appears to be the nylon of the nylock nut that caught fire. The terminals look pretty clean. The socket itself melted in two places.

I tested the voltage, things seemed ok. So I finished assembling the BMS, and connected the wires.

The BMS now reports the two affected cells are lower than the rest of the pack.
  1. Is this a short? I thought it might be, but I looked on the forums and other people's shorts seem to be really intense, like the leads of the batteries melting!
  2. How can I trouble shoot the two affected cells?
  3. What kind of problems can I expect to have in the future, and how do I identify them?
  4. Should I top balance again? (dismantle everything, put it back into parallel, and balance)
this is cheaper then blowing up a BMS or destroying a battery better yet, throw a bath towel over the areas you are not working on.

 
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