Capacitors type tests

Shunt power capacitors of non self-healing types up to and including 1000 V General performance, testing and rating. Safety requirements. Guide for installation and operation 13585-1/1994 BS EN 60931-1/1996... 

Shunt power capacitors of the self healing type for a.c. systems having rated voltage up to and including 1000 V Ageing test, self-healing lest and destruction lest 13.341/1992 BS EN 60831-2/1996... 

Shunt capacitors for a.c. power system rated voltage above 1000 V (non-self-healing type) Endurance testing 13925-2/1994 BS 7264-2/1990... 

Testing in the Carbon-Carbon type of Electrochemical Capacitors... 

In a manner analogous to TMA and DMA, a specimen can be subjected to a constant or oscillating electric field rather than a mechanical stress during measurements. Dipoles in the material will attempt to orient with the electric field, while ions, often present as impurities, will move toward the electrode of opposite polarity. The resulting current flow is similar in nature to the deformation brought about by mechanical tests and represents a measure of the freedom of charge carriers to respond to the applied field. The specimen is usually presented as a thin film between two metal electrodes so as to form a parallel plate capacitor. Two types of test can be performed. 

Usually external reference capacitors can be connected to the interface allowing an ultra-stable reference to be used if one is available. This also provides best matching of cable errors since the same type of connection cables can be used on the sample and on the reference. The reference technique is especially usefiil when using external amplifiers for high voltage tests, though the reference capacitor must be chosen with care to withstand the applied voltage level. 

In general, interference-suppression capacitors have low inductances. These capacitors can be separated into two classes depending on their use Class X and Class Y. Class X types are used in applications with lower safety requirements, for example, where a collapse would not pose a danger. Class Y types are used in environments or applications that have strict safety requirements. These two classes have different test conditions. For example, an 1100 V test voltage is used for testing Class X capacitors such as a 4 pF/250 V capacitor a... 

V test is used for testing Class Y capacitors. Both types are used in high (ceramic) and low (polymer) radio frequency and automotive applications. 

Comparison of impedance-frequency characteristics for various types of capacitors tested by the Matsushita Electrical Industrial Co. of Japan group. 

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