Manufacturing:
AMBER capacitors incorporate elements wound from
bi-oriented metallised
polypropylene film. The winding is done on fully computerized and automatic winding
machines.The metallization, which acts as an electrode
between the consecutive layers of polypropylene film, consists of layers of zinc, silver
and aluminium, which are vacuum deposited in controlled environments. The thin
metallization layer renders the self-healing property to the film. If, during operation,
the base film develops a fault, the cross sectional area at that point increases causing a
relative high resistance, and consequently high temperature, which evaporates the metal
around the fault and seals it. The metallization repairs or "heals" the
"wound" of the film and the capacitor operation is not impaired. The capacitance
loss due to the fault in the dielectric layer is negligible. After winding, the elements are
metal sprayed on their ends with high purity soft metals. This operation is performed by
specially designed metal spray guns, which melt the metal using electric arc. The molten
metal is sprayed on to the capacitor element ends, to which the terminals are fastened,
and the element is placed in its container, and finished.
All the materials used in the manufacturing of the
capacitors are purchased from world class manufacturers. During manufacture, the
capacitors are tested at various stages for verification of the quality and compliance
with the specifications. Testing: In addition to the type tests,
which are carried out on batches, each and every capacitor undergoes testing at four
stages during the manufacturing process.
- Automatic Clearing and Sorting:

During metal spraying stage
described above, the element is enveloped by thin layer of metal dust, which is later
cleaned. In spite of the cleaning, it is necessary to electrically clear the element at
low voltage so that the metal dust is evaporated and the capacitor is not short-circuited.
Also, it is important to check that the metal spray is conducting properly, and there are
no high resistance points. At AMBER, both these operations, and testing/sorting of the
elements to check their design and tolerances are carried out on a
fully Automatic Capacitor Clearing and Sorting Machine. All bad
elements, may they be due to high/low capacitance or dissipation factor, or short
circuited, etc., are automatically separated from the good ones.
- High Voltage Testing:
After the capacitor is
produced, high voltage tests are performed on 100% production as per the relevant
International Standards.
- Automatic Bridge Checking:
 After the High Voltage tests, 100% production is
tested on High Speed Component Testers, where capacitance and dissipation
factor is checked for compliance with the tolerance limits. Only after this stage of
testing, the capacitor is sent for printing.
- Physical Inspection:
After printing, and before packing, each and every capacitor is
physically examined for aesthetics of printing, terminals, container, etc.
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