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My camera shut down from low battery just when I needed to take some pictures.
The light was perfect. I suddenly remembered where I'd left the charger - 3000 miles away.
Everyone's had this experience, or the similar experience of spending one's vacation searching for a cellphone charger.
Here's how to charge any battery enough to keep doing the important stuff.
Fact 1: All past and future rechargeable batteries can be safely trickle charged if you don't overcharge them. Trickle means low current, like half an amp for an average camera or phone battery.
Fact 2: Small incandescent bulbs such as flashlight bulbs and christmast tree mini lights make great current regulators.
This is the battery to my Canon S30. It's got three terminals, labeled "+", "-", and "T".
I've clipped alligator-clips onto the two obvious ones.
You don't need clips, you can just hold wires on it for as long as it takes to charge, that's probably better anyway, so you can tell if anything is going wrong.
Warning! Wear eye protection and if anything weird happens don't breathe the fumes!
The light was perfect. I suddenly remembered where I'd left the charger - 3000 miles away.
Everyone's had this experience, or the similar experience of spending one's vacation searching for a cellphone charger.
Here's how to charge any battery enough to keep doing the important stuff.
Fact 1: All past and future rechargeable batteries can be safely trickle charged if you don't overcharge them. Trickle means low current, like half an amp for an average camera or phone battery.
Fact 2: Small incandescent bulbs such as flashlight bulbs and christmast tree mini lights make great current regulators.
This is the battery to my Canon S30. It's got three terminals, labeled "+", "-", and "T".
I've clipped alligator-clips onto the two obvious ones.
You don't need clips, you can just hold wires on it for as long as it takes to charge, that's probably better anyway, so you can tell if anything is going wrong.
Warning! Wear eye protection and if anything weird happens don't breathe the fumes!
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Signing UpStep 1Hands on Charging
What was that other terminal marked "T" for? TIMMY of course, just like in the nursery rhyme!
It's for Timmy to to hold his finger on the battery. If it gets hot you're doing something wrong.
Actually it's "Thermistor" or similar names. Temperature sensor. Some batteries use that to regulate charging current, some just for a safety feature.
"Digital sensor, huh?" would be a running joke back when Americans knew Greek and knew that digits are fingers. But then numbers got so much use we forgot about counting on fingers, and now people barely know how to do anything with their hands.
Anyway, here's a finger used as a digital thermometer. Which reminds me of the joke about the doctor...
It's for Timmy to to hold his finger on the battery. If it gets hot you're doing something wrong.
Actually it's "Thermistor" or similar names. Temperature sensor. Some batteries use that to regulate charging current, some just for a safety feature.
"Digital sensor, huh?" would be a running joke back when Americans knew Greek and knew that digits are fingers. But then numbers got so much use we forgot about counting on fingers, and now people barely know how to do anything with their hands.
Anyway, here's a finger used as a digital thermometer. Which reminds me of the joke about the doctor...
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Don't get me wrong, you really REALLY don't want to ground out a coil pack or a distributor. It'll feel like having your arm yanked on while being covered in a shower of angle grinder sparks.
But it is NOT the fact that it's DC that makes it less dangerous - plenty of people have been electrocuted by high voltage DC. It's the fact that the battery voltage is so low. Coil packs can generate 50,000 volts or more - that's why they are more dangerous than the battery.
Just want to make sure that no one thinks that DC current is "safe", that's the way people get careless, and killed.
Unfortunately it's not that simple either.
The characteristic of a power supply that makes it dangerous is actually the.. um ... power rating. And that's best determined from the current (Amps) rating. High voltage IS what will let the power supply (battery / whatever) overcome the high resistance (low conductivity) to get to your vital organs, but current gives it the power to do something when it gets there.
So any high current situation is dangerous, PARTICULARLY at high voltage.
And your car battery has plenty power to do serious damage under the right circumstances.
The amount of current that can kill you is so small (anything over about 100 milliamps - that's tiny!) , that almost any power supply can kill you if it has enough voltage to push the current through your skin.
A 1000V power supply that can only deliver .2 amps is just as deadly - at least from electrocution - as a 1000V power supply that can deliver 100 Amps. The converse: A 12V battery that deliver 600 amps is not any safer than the same battery that can only deliver 5 amps.
The rest is semantic argument and probably not best suited for this thread. But i'd be glad to learn more if you want to message me.
therefore, digital sensor could be interpreted as 'finger sensor'
With all of that behind us, I have a lovely drill and I accidently threw out the charger for the batteries. No problem, I whipped out the 'ole car charger with both 6volts and 12 volts settings and a trickle setting for each voltage at 2 amps or a charge of 6 amps for bigger batteries, like a car battery as the manufacturer intended. I placed the charger on 6volt, 2amp trickle, tested temp, set a timer, and all is at peace now. Very easy fix just be sure to use the right setting, do it in the right place (not in your house), and right time (when no one else is around to get their fingers in the way like my son wanted to do).
The real fun was that neither the battery nor the drill listed which terminal was positive or negative. That is easy enough to fix because the charger has a built in indicator of charge and if you get it backwards...it is obvious.
Do not be so scared, it is for individuals that understand electricity and know when to stop, however it can save you from a major problem if a device is dead and you MUST have it.
Heaven forbid if I'm driving through the mountains and get stranded without my phone charger, and my phone dies, at least now I know i can hack together a few wires, and light bulbs to charge my phone to send out that brief but urgent SOS. That's empowering to know.
I have bought a new charger 3 days ago.