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ArcticMyst Security by Avery

Holy $#!% Ultra-Capacitor

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It's not an electrolytic. There IS no reverse polarity. You would need to charge it well beyond 4KV to blow it up.
 





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Looks like they're all sold out! Good thing I got five!

I thought about buying some, but then I decided that a car battery can supply similar (if not more) current at a higher voltage then one of these, and I alredy have a car battery sitting around.
 

Fiddy

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Nice work!!

My question is why did it take 4 hours to charge?

here are my calculations.

236 Farad @ 27.5V

8A / 236 Farad = 0.033V / second

27.5V / 0.033V = 833.33 seconds = 13.88 minutes

:thinking::thinking:
 

vk2fro

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His power supply might have been folding back due to the overcurrent protection kicking in.

Use a resistor in series (50 watter) to charge them.
 
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vk2fro

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I remember using a low value resistor in the preheat circuit of my ion laser power supply MK1 thru 5 - its was the simplest form of current inrush limiting. During the 40 second preheat delay, as the filiment of the ion tube warmed up, the main filter cap would precharge via the resistor (think it was 270R 5W). Once the delay had expired, the operational controls came online, and the resistor was shorted. If it was left inline, the many amps drawn by the tube would suck the cap dry.

I had a problem every time I went to use my laser it would trip the breaker. It was the cap appearing as a dead short to the transformer doing it. This resistor solved the problem :)
 

Things

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Fiddy, when discharged, most ultracaps will appear as a direct short circuit to power supplies. Without inrush protection, most power supplies will detect this short circuit, and cut off the power to protect themselves.

Using a resistor, you are allowing the power supply to gradually charge the capacitors to the point where they no longer look like a short circuit.
 
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I thought about buying some, but then I decided that a car battery can supply similar (if not more) current at a higher voltage then one of these, and I alredy have a car battery sitting around.

Sure they can, but you can't discharge them many times (like more than 10 times) or else they die very quickly. You'd probably want to use a deep cycle battery if you're planning on discharging them often.
 
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Deep cycle isn't designed for super-high peak current like an engine-starting battery. You wouldn't need to discharge is all the way, anyway. Just keep a battery charger on the thing while you use it :)
 
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One neat use of these caps is with a powerful DC-AC inverter to supplement a 12V battery bank to build a solar water well pump driver. These caps have enough kick to where you can use normal heavy duty deep cycle batteries for this project. You can also make a emergency car starter rig with these caps that will start almost any normal automotive engine.
 

Things

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It'd be interesting to check the leakage on these over time. You could have them trickle charge from your cigarette lighter socket, and use them to jumpstart the car if you ever break down.
 

Fiddy

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It'd be interesting to check the leakage on these over time. You could have them trickle charge from your cigarette lighter socket, and use them to jumpstart the car if you ever break down.

They do self discharge pretty quickly, ive carried my bank in my car for jump-starting :)
 
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I have come into possession of one of the first if not the first flashlights to run off of supercapacitors. It is a Light for Life pc3-300. Currently trying to rig up a charger for it. The pinout of the 4 pin connector is a pin for data, ground, +12V, and "C3+out"

It has 3 2.3V 300F "pseudocaps" made by nesscap.

What is a standard charging procedure for caps in series? Match the voltage and limit the current?
 

Fiddy

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I have come into possession of one of the first if not the first flashlights to run off of supercapacitors. It is a Light for Life pc3-300. Currently trying to rig up a charger for it. The pinout of the 4 pin connector is a pin for data, ground, +12V, and "C3+out"

It has 3 2.3V 300F "pseudocaps" made by nesscap.

What is a standard charging procedure for caps in series? Match the voltage and limit the current?

Before i start charging capacitor banks, i like to balance charge each capacitor. So i will charge each capacitor individually to say 200mV so they each start off with the same charge in each capacitor, but because each capacitors ESR are going to be slightly different, they will charge a different rates than each other.

What i do is set the Constant Voltage charge system to 90% of the banks fully charged voltage.
Then set the constant current charge to near max current.

In your situation the max voltage of the bank is 6.9V

So id set the Constant Voltage for 6.21V (90%)

Then turn the current up to near maximum, for arguments sake say your power supplies max current is 5A set it to 4A or something like that.

Monitor each capacitors voltage with a multimeter while charging, i do this to make sure we don't get a over-voltage situation on a single cap in the bank, because they tend to explode if over charged.

Now say your bank has reached 6.21V (90%), measure each capacitors voltage, if they are perfectly balance each cap should be 2.07V's.
At this point i charge each cap individually until they reach their full voltage, in this case 2.3V.

Theres my run down! Enjoy!

Fiddy.
 
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