NOISE WHEN CHARGING 1FARAD CAPACITOR

[TECHBERT]

When charging my 1 Farad Nakamichi car audio capacitor it get's to 6 volts and stops charging and makes a ticking sound. Is this the halfway point where electricity is passing from one side to the other and expanding inside or is there something wrong. The LED volt meter did not switch on, I presume it needs to be at 8volts for that to happen. At that time I had 1/4 watt resistor and I was wondering if it was charging too slow or not at all. I now have 1 watt resistors in case. I need to check before I try again in case the capacitor might be faulty.

Has anyone heard their capacitor making a ticking or clicking noise when charging?

Thanks.

 

[mindless1]

Do you have just the one capacitor? I mean if it was wired wrong and you had two capacitors in series around the power rails then the most each would ever get to is half the battery voltage.

Another thought is that once the voltage gets high enough a relay is trying to click on but the relay plus the powered load is higher current draw than passing through your resistor because the ohm value of it is too high. I don't know this to be true, and it would seem unusual, but "could" happen.

Can you link a spec sheet and instructions or even better a schematic of the attached circuitry integral to the capacitor-product?

I can't speak about this specific capacitor product, but in general you should be able to measure the voltage going in on the +/- power rails and it should be very nearly the same as the battery voltage, IF measured before rather than after the resistor where the voltage will be lower.

It is the ohm value of the resistor that determines how fast it charges so using the same ohm value but moving from a 1/4W resistor to a 1W resistor only decreases the amount it heats up (same amount of heat created but lower thermal density). You may NEED at least a 1W resistor to have it not heat up too much, but "capacitors" in general would charge fine at a slower rate with a higher ohm value and thus not need as high a wattage rating. The circuit they've added to it is the wild card.

I would contact Makamichi or an authorized distributor and ask them if the added-on circuitry has any charging complexity requirement.

What ohm value resistor are you using? If you were starting from zero and managed to get it up to 6V, you are definitely charging it, and the same resistance value should continue to charge it but at a progressively slower and slower rate as the capacitor gets near the battery voltage, but at only 6V, it is nowhere near that and you should keep seeing voltage rise unless there is an interaction with the attached circuit eating the limited amount of current going to it, as mentioned in my 2nd paragraph above.

 

[TECHBERT]

Do you have just the one capacitor? I mean if it was wired wrong and you had two capacitors in series around the power rails then the most each would ever get to is half the battery voltage.

Another thought is that once the voltage gets high enough a relay is trying to click on but the relay plus the powered load is higher current draw than passing through your resistor because the ohm value of it is too high. I don't know this to be true, and it would seem unusual, but "could" happen.

Can you link a spec sheet and instructions or even better a schematic of the attached circuitry integral to the capacitor-product?

I can't speak about this specific capacitor product, but in general you should be able to measure the voltage going in on the +/- power rails and it should be very nearly the same as the battery voltage, IF measured before rather than after the resistor where the voltage will be lower.

It is the ohm value of the resistor that determines how fast it charges so using the same ohm value but moving from a 1/4W resistor to a 1W resistor only decreases the amount it heats up (same amount of heat created but lower thermal density). You may NEED at least a 1W resistor to have it not heat up too much, but "capacitors" in general would charge fine at a slower rate with a higher ohm value and thus not need as high a wattage rating. The circuit they've added to it is the wild card.

I would contact Makamichi or an authorized distributor and ask them if the added-on circuitry has any charging complexity requirement.

What ohm value resistor are you using? If you were starting from zero and managed to get it up to 6V, you are definitely charging it, and the same resistance value should continue to charge it but at a progressively slower and slower rate as the capacitor gets near the battery voltage, but at only 6V, it is nowhere near that and you should keep seeing voltage rise unless there is an interaction with the attached circuit eating the limited amount of current going to it, as mentioned in my 2nd paragraph above.

I tried the recommended value resistors 1/4 watt and 1 watt Carbon Resistor, 5%, 1k and they both slow at 6 volts and the cap then makes a ticking noise. It states in the instructions that it does not matter what way I charge them though I attached the battery + to capacitor + and battery minus to capacitor minus. The main problem is the ticking noise. I am not sure if that should happen. I have 2 1Farad caps and both make the noise when charged separate with a 13.6 volt battery that has a nominal 10 amp DC current.
Thanks for the trying. Robert.

 

[mindless1]

1K ohm is an often recommended resistor value so I'd think it should work and you might have a defective cap. I would contact the manufacturer and ask them.

 

[TECHBERT]

I do not know if it might be slow. I stopped charging when I heard the noise because it sounded like it was expanding. I might try charging it outside. If it pops it pops. Not much I can do now. They might charge slower on resistors, I remember someone on youtube saying though I can not find the video.

 

[mindless1]

Expanding? Make a video of this and link to it.

Yes of course they charge slower through a resistor which is the point, to get the charge in without a huge surge that blows the fuse (that it "should" have, many people charge them by taking that dedicated fuse out and putting the resistor in its place to charge the cap, then once charge fully the fuse is swapped back in, though if the resistor gets hot you don't want it touching any plastic on a fuse holder).

Keep in mind that if you have more than one, 1K resistor, you can put several in parallel, and that might get you over the hump if the situation is as I first mentioned, that a relay is being activated and at that moment using as much power as is being put in so it keeps switching on and off.

 

[TECHBERT]

Thanks. I have signed up to PSMA that specialise with Capacitors. I will see what they have to say.

 

[mindless1]

Not what I meant, this is not a general capacitor issue, it is one specific to the design of the particular product you have (the circuit added on besides the capacitor itself) so the contact would be Nakamichi or an audio shop familiar with them, perhaps where you bought it.

If you want forum support then a car audio forum where the members use that cap would be more direct advice.