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Message: <blockquote data-quote="BerniniCaCO3" data-source="post: 7477366" data-attributes="member: 636434">Mind you I've never used a capacitor before, but I've read the literature, remember my high school electricity&amp;magnetism, and believe I get it.I just got a brandy new capacitor in the mail yesterday, was going to install it tomorrow, decided to charge it today.  Err, apparently any sort of url link is prohibited, but the model is a Pyle Audio "PLMRCAP18 1.8 F 20V Round Marine Capacitor" bought from amazon.It IS a bad sign that in several places on the package and on the capacitor itself, it calls itself a "maring" capacitor instead of a "marine" capacitor....Anyway.I charged it as directed: I hooked it up to my battery, in parallel, (positive to positive, neg. to neg.) with the resistor in series, which as I understand, limits a current spike especially when the capacitor is at 0V and 0ohms resistance and the battery is at 12.5x volts.It very rapidly climbed to 10.2x volts and stopped there, presumably the resistor was consuming 2.3v.At this point I took the resistor out and hooked the battery up directly, and the capacitor instantly came to equilibrium with battery voltage.Now, I unhooked it, thinking it fully charged.  I decided to check the voltage with my own voltmeter.  It was , really just a few seconds after unhooking from the battery, now at 10.xx volts.  I held the voltmeter to it, and watched the voltage drop quickly, to 9.xx volts, 8 volts... Just in case the voltmeter itself was consuming all the power this 1.8Farad capacitor could supply, I let it be and came back in 5 minutes.  At this point it was down to .73 volts and holding steadyish.So at the very least, open-circuit, NO load WHATSOEVER, terminals not connected in any way, my capacitor dropped of its own accord from 10 volts to less than 1 in between voltmeter measurements just minutes apart.This makes the idea of precharging a capacitor absolutely laughable; it will discharge itself to .7 volts before I've even half finished soldering its connections!Is this normal?  For capacitors to leak this quickly internally?  Or should that capacitor have held some charge for at least a few minutes... if not days, frankly, given a claimed 1.8Farads.I'm fearing that there's an internal short that is both consuming energy, and perhaps seriously castrating the actual capacitance to be much less than 1.8FI'm thinking I need to return this.And buy a different capacitor (quite open to advice) that doesn't call itself a maring capacitor and sometimes a marine capacitor.But I thought I'd check with you guys first before I cry for my money back, just in case this is normal behavior, seeing as I'm really not experienced working with capacitors.And if I do need to return this, what brands/models have you found highest in quality and most durable?In point of fact this is not going to supply an amp, but an electric fan, and it's going to live in the more hostile engine compartment; tucked behind the front fascia furthest from the engine's heat but not immune to moisture, if that influences advice.I was also reading up on electrolytic capacitors, which this Pyle capacitor is, and apparently they're a little more delicate than solidstate (if that's the technical term-- not containing salt water anyway) capacitors?Who makes a non-electrolytic capacitor, if in fact they're more durable?</blockquote>

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