ALUMINUM ELECTROLYTIC CAPACITORS 알루미늄 전해 캐피시터 사용 방법

ALUMINUM ELECTROLYTIC CAPACITORS
출처 http://www.samwhatech.co.kr/

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Application guidelines
Correct application and strict adherence to the important
information listed below, will be ensure optimum performance
of the capacitors over their entire specified life.
1. POLARITY
If you should reverse the polarities of a aluminum electrolytic
capacitor, it would lead to short-circuited circuitry and may
further result in an explosion if the unit is kept energized.
SAMWHA offers unit of 6.3 or more with safety vent design
as the standard type in order to prevent possible accidents that
may take place if the unit should be connected with its polarities
reversed.
It is advisable to use non-polar capacitors for a DC circuit where
the polarity is to be reversed.
2. OVERVOLTAGE
Do not apply overvoltage. When overvoltage is applied to the
capacitor, leakage current increase drastically, causing heat
generation, short-circuit or breakage.
3. RIPPLE LOAD
The rated ripple current given for certain conditions (Temperature,
Frequency) shall not be exceeded. If so, early failure
may result.
The sum of DC-bias and maximum amplitude of ripple voltage
shall be within rated voltage and 0V. Electrolytic capacitors are
not normally designed for AC application.
4. TEMPERATURE RANGE
Use the electrolytic capacitors according to the specified
operating temperature range. Usage at room temperature will
ensure longer life.
5. CHARGE/DISCHARGE
If used in circuits in which charge and discharge are frequently
repeated, the capacitance value may drop, or the capacitor may
be damaged. Please consult our technical department for
assistance in these applications.
6. FOR SERIES CONNECTION
Aluminum electrolytic capacitors may be connected in series, but
when doing so it should be noted that the voltage distribution will
be according to their leakage currents. This phenomenon may
induce irregularities in voltage load and cause maximum ratings
to be exceeded, this could have drastic consequences especially
with high voltage capacitors. Series connected electrolytic
capacitors should therefore be supplied the voltages shall be
proportionally distributed by balancing resistors.
balancing
resistor
ALUMINUM ELECTROLYTIC CAPACITORS
7. FOR PARALLEL CONNECTION
When you install more than 2 capacitors in parallel, consider the
balance of current flowing into the capacitors.
8. LEAD STRESS
Do not apply excessive force to the lead wires or terminals. If
excessive force is applied to the lead wires and/or terminals,
they may break and cause an open circuit. After mounting,
avoid holding or applying force to the capacitor. Do not twist or
carry the PC board by grasping the capacitor body after the
capacitor are soldered to the PC board.
9. MOUNTING
The distance between the terminal holes on the circuit board
should be the same as that between the lead wires or terminals
of the capacitor. Excessive force in mounting on circuit boards
should be avoided.
Improper insertion of the lead wires in circuit board may cause
electrolyte leakage, break the lead wires or impair their
connection with the internal elements.
When the distance between the two terminal holes on the
circuit board cannot be reduced to that between the lead wires,
lead formed capacitors are recommended.
The main chemical solution of the electrolyte and the separator
paper used in the capacitors are combustible. The electrolyte is
conductive. When it comes in contact with the PC board, there
is a possibility of pattern corrosion or short circuit between the
circuit pattern which could in result smoking or catching fire. Do
not locate any circuit pattern beneath the capacitor end seal.
In order to prevent possible damage by vibration on the circuit
board, kindly bond our capacitors on the circuit board or use
any fastening devices.
hole
hole
There should not be any circuit pattern or circuit wire above the
capacitor safety vent.
Unless otherwise specified, following space should be made
above the capacitor safety vent.
ALUMINUM ELECTROLYTIC CAPACITORS
If the capacitor safety vent is placed toward circuit board, the
hole should be made to match the capacitor vent position.
Do not install screw terminal capacitor with end seal side down.
When you install a screw terminal capacitor in a horizontal
mount, the positive terminal must be in the upper position.
10. SOLDERING
In the dip soldering process of PC board with aluminum
electrolytic capacitors mounted, secondary shrinking or crack of
the sleeve may be observed when solder temperature is too
high and/or dipping time is too long.
If the lead wire of other components or pattern of bothsided PC
board is close to the capacitor terminal the similar failure may
be also originated.
Please avoid having flux adhere to any portion except the
terminal. Solder iron does not touch any portion of capacitor
body.
11. Cleaning, Mounting of the PCB after soldering
1)When you clean a PCB, halogen cleaning agents can cause
corrosion of aluminum foil and lead tab. If you need to clean,
please replace lsopropyl Alcohol(IPA), Water as halogenated
cleaning atents.
2)5minutes either by ultrasonic, vapor or immersion cleaning
method.(chip type:2minutes) Be careful not to apply
mechanical stress to the terminals or lead wires
3)Common type of halogenated cleaning agents are listed
below
Don’t use the solvents listed above as clearning solvent
agents even for solvents proof capacitors, because it has
strong chemical reaction.
4)When using a latex-based adhesive on the capacitor’s rubber
end seal for adhesion to a PCB, corrosion may occur
depending on the kind of solvent in the adhesive. Select an
adhesive as an organic solvent with dissolved polymer that is
not halogenated hydrocarbon.
Representatice
Brand Name
Structural
Formula
Chemical Name
Trichlorotrifluoroethane
Fluorotrichloromethane
1,1,1-Trichloroethane
Trichloroethylene
Methyl Chloride
C CI F
CCI F
C H CI
C HCI
CH CI
Freon TF, Daiflon S-3
Freon-11, Daiflon S-1
Cholroethene
Trichlene
MC
Trichlorotrifluoroethane
Fluorotrichloromethane
1,1,1-Trichloroethane
Trichloroethylene
Methyl Chloride
C CI F
CCI F
C H CI
C HCI
CH CI
Freon TF, Daiflon S-3
Freon-11, Daiflon S-1
Cholroethene
Trichlene
MC
ALUMINUM ELECTROLYTIC CAPACITORS
SNAP-IN
12. INSULATION MATERIAL
Sleeve material
The standard sleeve material is polyvinyl chloride, if exposed
to xylene, toluene, etc. and then subjected to high
heat, the sleeve may crack.
Case and cathode terminal
The case of capacitor is not insulated from the cathode
terminal.
Dummy terminals for snap-in type
Dummy terminals are not insulated from the element.
Dummy terminals are for added stability only, and should
never be electrically connected to either the positive or
negative terminal.
13. STORAGE
Do not store the capacitors in high temperature and high
humidity conditions. Avoid direct sunlight.
(Recommendable conditions : 5 to 35 , 45 to 75% RH)
Store the capacitors in the package.
Capacitors should not be direct contact with water, brine
or oil.
Capacitors must not be exposed to toxic gases such as
hydrogen sulfide, sulfurous acid, nitrous acid, chlorine, or
ammonium.
When the capacitor is stored for a long time without
applying voltage, leakage current tends to increase, due
to deterioration of aluminum oxide film. This returns to
normal by applying voltage. Apply voltage(Aging) before
use if the capacitor is stored long time.
It is recommended to apply DC working voltage to the
capacitor for 30 minutes through 1k of protective series
resistor.
5)Penetration Channel of Solvent and Corrosion Mechanism
Penetration between the
rubber and the aluminum case
Penetration between the
rubber and the lead wires
Penetration through the
rubber
CI-gotten inside a capacitor
reacts with aluminum.
AI + 3CI- AICI3 + 3e-
Then, AICI3 resolves in water
AICI3 + 3H2O AI(OH)3 + 3H+
+ 3CIThus,
the CI- ion is freed again
and repeats the corrosion of
aluminum.
ALUMINUM ELECTROLYTIC CAPACITORS
14. IN AN EMERGENCY
If some gas blow out from the capacitor due to operation
of safety vent, immediately turn off the main switch or pull
out the plug from the power source.
When the safety vent operates, do not draw your face the
safety vent since gas which in over 100 will be emitted.
If your eyes entered or breathed the gas, immediately
wash out your eyes and mouth with pure water.
Do not touch electrolyte. If your skin is exposed to
electrolyte, please wash it away using soap and water.