Aluminum Electrolytic Capacitor
(5)Clearance for Case Mounted Pressure
Relief Vents
2.Capacitor Handling Techniques
2.1Considerations Before Using
Capacitors with case mounted pressure relief vents
require sufficient clearance to allow for proper vent
operation. The minimum clearances are dependent
on capacitor diameters as follows.
(1) Capacitors have a finite life. Do not reuse or
recycle capacitors from used equipment.
(2) Transient recovery voltage may be generated in
the capacitor due to dielectric absorption. If
required, this voltage can be discharged with a
resistor with a value of about 1 kΩ.
(3) Capacitors stored for long periods of time may
exhibit an increase in leakage current. This can
be corrected by gradually applying rated voltage
in series with a resistor of approximately 1 kΩ.
(4) If capacitors are dropped, they can be damaged
mechanically or electrically. Avoid using dropped
capacitors.
f6.3 to f16 mm : 2 mm minimum,
f18 to f35 mm : 3 mm minimum.
f40 mm or greater: 5 mm minimum
(6)Clearance for Seal Mounted Pressure
Relief Vents
A hole in the circuit board directly under the seal
vent location is required to allow proper release
of pressure.
(7)Wiring Near the Pressure Relief Vent
Avoid locating high voltage or high current wiring
or circuit board paths above the pressure relief
vent. Flammable, high temperature gas exceeding
100°C may be released which could dissolve the
wire insulation and ignite.
(5) Dented or crushed capacitors should not be
used. The seal integrity can be compromised
and loss of electrolyte/shortened life can result.
2.2Capacitor Insertion
(8)Circuit Board Patterns Under the Capacitor
Avoid circuit board runs under the capacitor as
electrolyte leakage could cause an electrical short.
(9)Screw Terminal Capacitor Mounting
● Do not orient the capacitor with the screw terminal
side of the capacitor facing downwards.
● Tighten the terminal and mounting bracket screws
within the torque range specified in the
specification.
(1) Verify the correct capacitance and rated voltage
of the capacitor.
(2) Verify the correct polarity of the capacitor before
inserting.
(3) Verify the correct hole spacing before insertion
(land pattern size on chip type) to avoid stress
on the terminals.
(4) Ensure that the auto insertion equipment lead
clinching operation does not stress the capacitor
leads where they enter the seal of the capacitor.
For chip type capacitors, excessive mounting
pressure can cause high leakage current, short
circuit, or disconnection.
1.6Electrical Isolation of the Capacitor
Completely isolate the capacitor as follows.
● Between the cathode and the case (except for
axially leaded B types) and between the anode
terminal and other circuit paths.
● Between the extra mounting terminals (on T types)
and the anode terminal, cathode terminal, and
other circuit paths.
2.3Manual Soldering
(1) Observe temperature and time soldering
specifications or do not exceed temperatures of
350°C for 3 seconds or less.
(2) If lead wires must be formed to meet terminal
board hole spacing, avoid stress on the leadwire
where it enters the capacitor seal.
(3) If a soldered capacitor must be removed and
reinserted, avoid excessive stress to the capacitor
leads.
1.7Capacitor Sleeve
The vinyl sleeve or laminate coating is intended for
marking and identification purposes and is not meant
to electrically insulate the capacitor.
The sleeving may split or crack if immersed into
solvents such as toluene or xylene, and then exposed
to high temperatures.
(4) Aviod touching the tip of the soldering iron to the
capacitor, to prevent melting of the vinyl sleeve.
Always consider safety when designing equipment
and circuits. Plan for worst case failure modes such
as short circuits and open circuits which could occur
during use.
(1)Provide protection circuits and protection devices
to allow safe failure modes.
(2)Design redundant or secondary circuits where
possible to assure continued operation in case of
main circuit failure.
Design, Specifications are subject to change without notice. Ask factory for technical specifications before purchase and/or use.
Whenever a doubt about safety arises from this product, please inform us immediately for technical consulation without fail.
– EE19 –