LYCOS RETRIEVER 
Capacitor
built 195 days ago
The Capacitor Wizard is an extremely FAST and RELIABLE device designed to measure ESR (Equivalent Series Resistance) on capacitors of 1uf and larger "IN CIRCUIT" eliminating the need to remove the capacitor for accurate tests. The Capacitor Wizard finds BAD caps IN CIRCUIT that even VERY EXPENSIVE cap checkers MISS ENTIRELY, even out of the circuit!! (See Doug's Tech Notes.)
Source:
Capacitor electrolytes are high-resistivity, organic (glycol base), liquid solvents with one or more dissolved, ionically conductive solutes. Regardless of the specific chemical composition of the capacitor electrolyte solution used, the desired capacitor electrolyte bath performance can only be achieved when relatively narrow operating limits of pH, water content, conductivity, and contaminant levels (particularly chlorides), are maintained. The chemistry and chemical stability of the capacitor electrolyte bath greatly influences the frequency characteristics and high temperature load life of the capacitors processed in the capacitor electrolyte bath. With time, particularly at elevated temperatures, these capacitor electrolyte bath solutions typically become contaminated with solvent/glycol degradation products and must be discarded. Disposal of spent capacitor electrolyte baths can be costly and wastes a valuable resource that is preferably decontaminated and reused.
Source:
The Capacitor Wizard is 'THE' fast and reliable way to find bad capacitors using ESR. Most capacitance meters read only the capacitance value - but did you know that a change in value is not the usual way for capacitors to fail? Instead, The Capacitor Wizard looks at the [reference/esr.htm ESR] (Effective Series Resistance).
Source:
Discharging the Capacitor: If you're going to remove your capacitor for some reason, you may want to completely discharge the capacitor to prevent creating a hazardous situation. To discharge the capacitor (after it's disconnected from the system), simply provide a path for the current to flow from one terminal to the other. You can use either the test light or the resistor. After it is discharged, you may want to connect the terminals together with a piece of wire or resistor. Some large capacitors will act like a battery and develop some small voltage across its terminals. Since the capacitor is likely a large capacitor (over 1/2 farad), the small voltage could be dangerous.
Source:
The black band indicated which end of the paper capacitor had some metal foil (which acted as a shield). The end with the metal foil was connected to the ground (or lowest voltage). The main purpose of the foil shield was to make the paper capacitor last longer.
Source:
In order to obtain the tight contact between the seat and the capacitor, an adhesive resin is used to fasten the aluminum case to the seat by securing it immovably. Additionally, in order to take full advantage of the tight connection between the seat and the capacitor, the seat is equipped with two in-mold supplemental terminals. These four terminals (the electrode terminals and the supplemental terminals) should be used to ensure tight contact between the product and the printed wiring board by soldering the terminals in the reflow process. This makes it possible to secure the entire capacitor to the wiring board using the in-mold supplemental terminals. Thereby, it will reduce the stresses on the electrode terminal and improve the vibration durability.
Source:
MORE ABOUT
Capacitor