One gassed and ready to pop and one that has gone.
You would not want to be anywhere near the dam thing in this state.
The energy in fault current out of a simple car battery is huge under short circuit conditions be careful
This is a picture of 2 batterys I have had to replace.
One gassed and ready to pop and one that has gone.
You would not want to be anywhere near the dam thing in this state.
The energy in fault current out of a simple car battery is huge under short circuit conditions be careful
it never ceases to amaze me that folks will spend thousands on building a car (thousands on just the engine) then wire the car with left over wire
from the house extension that the wife demanded as the price for your new hobby, then they wonder why nothing works as it should.....
Car battery's can deliver 1000A+ in a short circuit situation and make very short work of your loom. it is extremely easy to rewire a kit car,
you dont even have to sacrifice any chickens!! the battery's above show how it can go all wrong.
I've seen generator batteries overcharged or exploded all the time. Most recentLy, I had to send out a technical bulletin internally to make our
staff aware of the dangers. The issue isn't so much with the short circuit fault current, it's with the force of the explosion and the
gases which are flammable.
Most recent one I've seen in St Albans, the battery had blown its top off, and shattered a 1/2" ply timber box sitting over it.
The most common cause? Low electrolyte.
[Edited on 24-4-12 by MakeEverything]
Ive got more pics that have similar results........
I have a bigger respect for dc than AC......
quote:
Originally posted by mangogrooveworkshop
I have a bigger respect for dc than AC......
This is like the tesla Edison ac dc debate of the late 19 th century. Which is more dangerous etc.
Very interesting chap tesla was, "the man who invented the 20th century" is a cracking read all about him.
Two seperate failure distinctions to make - not to mention the acid itself.
Mango - those batteries should have been vented to prevent a failure like that?
Makey - look like a hydrogen explosion to do that kind of damage. eg Hydrogen ignited by heat from low electrolyte.
Loom protection - Why not use a fusible link? Never had to try one in action, but installed a Ford item just as a precaution.
In our case battery pack was installed on its side and the thermo was unplugged
They are a problem because of a design fault created before my time at design stage.
We only deal with the issues as they fail.
When I were a lad we used to "test" customer's flat batteries by putting a bit of weld wire across the terminals.
One time the battery was far from dead and the weld wire fused itself into my skin!
Needless to say we started using the proper equipment after that.
Cheers, Pewe10 
Tesla one of my all time heros alongside IKB.
quote:
Originally posted by iank
quote:
Originally posted by mangogrooveworkshop
I have a bigger respect for dc than AC......
Agreed DC of the same magnitude is much more dangerous than AC.
quote:
Originally posted by MikeRJ
quote:
Originally posted by iank
quote:
Originally posted by mangogrooveworkshop
I have a bigger respect for dc than AC......
Agreed DC of the same magnitude is much more dangerous than AC.
There really isn't much in it. Both are quite capable of killing you at high voltages and both are equally capable of starting fires under fault conditions.
Diesel/Electric submarines will teach you everything you want to know about battery safety. Like lead-acid + Salt Water = Chlorine gas....nasty in a sealed environment.
quote:
Originally posted by jeffw
Diesel/Electric submarines will teach you everything you want to know about battery safety. Like lead-acid + Salt Water = Chlorine gas....nasty in a sealed environment.
quote:
Originally posted by MikeRJ
quote:
Originally posted by iank
quote:
Originally posted by mangogrooveworkshop
I have a bigger respect for dc than AC......
Agreed DC of the same magnitude is much more dangerous than AC.
There really isn't much in it. Both are quite capable of killing you at high voltages and both are equally capable of starting fires under fault conditions.
there is enough power in a watch battery to kill you, its not volts it amps that is the problem, if it were every time we got a shock shuffling across
the floor we would kill our selves, a vacuum cleaner is about 1000w or 3-4 A and it will hurt if you get a shock but your starter motor is also about
1000w but a shock from close to 100A (and up to 1000A) is going to give you a real problem.
[Edited on 24/4/12 by snowy2]
Battery goes bang as you're leaning over the engine bay; acid in eyes; trip over tools/junk as you jump back; crack head on floor and knock
yourself out; come to blind for the rest of your life.
Jaguar X300s (6cyl) and X308s (8cyl) have nice dual-output fusible link holders in the boot. (one for the starter with 2x 250A fuses; one for
everything else with a single 250A fuse) and are common in scrappers. Convenient for isolation of batteries where the terminals are difficult to get
to too, and more reliable than the cheapo battery cut-off switches. (I've had three in my time, and all three have failed. One dead short, one
high resistance and fire, one high resistance and luckily wouldn't crank so didn't catch fire. Eurgh!