DiyMobileAudio.com Car Stereo Forum banner

1 - 4 of 4 Posts

·
Registered
Joined
·
31 Posts
Discussion Starter #1
Hello, purchased an NVX XCAP 1F for my system. I am running 45 amps, speaker and sub amps. Bought the cap to try and filter what I believe to be an AC ripple in my system. Went to precharge the cap with the supplied resistor. Couple issues presented itself, mind that I am new to capacitors. Cap meter flashes up to 10v, and charges to 10v quite quicky. Once at 10v flashing subsides, and charges to 11 volts slowly. Light on resistor chip would de illuminate around 11v, and cap would stop charging. With engine running, cap would charge to 12.5v. As soon as resistor unplugged, voltage would rapidly drop to zero. Green charging light not illuminated. Bad capacitor?

On a side note, I read somewhere that capacitors actually take more draw from the alternator? I disagree, I believed capacitors were just an extra power storage bank, and shouldn't need to be continuously charged up.

What do you guys think, bad capacitor? Or am I just overthinking as usual

Chase.

Sent from my LG-LS993 using Tapatalk
 

·
Registered
Joined
·
560 Posts
If you charge the cap and unplug it, it should hold a charge if there is nothing to drain it. Unless the cap has a meter right on it that's draining it, it sounds like it may be bad. What size is the cap? Caps can put a huge load on your alternator if there is a voltage difference. The internal resistance is really low so it's like a dead short on an alternator if it sitting at 0. If it's charged to 12 or 13 and you start your car it shouldn't be that big of a load.
 

·
Registered
Joined
·
31 Posts
Discussion Starter #3
If you charge the cap and unplug it, it should hold a charge if there is nothing to drain it. Unless the cap has a meter right on it that's draining it, it sounds like it may be bad. What size is the cap? Caps can put a huge load on your alternator if there is a voltage difference. The internal resistance is really low so it's like a dead short on an alternator if it sitting at 0. If it's charged to 12 or 13 and you start your car it shouldn't be that big of a load.
It's 1 Farad. As soon as I unplug the charging chip, the meter on cap starts dropping. It's like it's auto discharging.

Sent from my LG-LS993 using Tapatalk
 

·
Registered
Joined
·
180 Posts
Caps should maintain their charge for weeks. Sounds like it has a problem. You would not want a cap to "auto-discharge" as it would need to be charged every time you start the car - not good!
 
1 - 4 of 4 Posts
Top