T22

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Revision: 13-May-2020

7

Document Number: 40187

THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT

PERFORMANCE CHARACTERISTICS

1.

Operating Temperature: capacitors are designed to

operate over a temperature range of -55 °C to +125 °C.

2.

DC Working Voltage: the DC working voltage is the

maximum operating voltage for continuous duty at the

rated temperature.

3.

Surge Voltage: the surge voltage rating is the maximum

voltage to which the capacitors should be subjected

under any conditions. This includes transients and peak

ripple at the highest line voltage.

3.1 The surge voltage of capacitors is 115 % of rated DC

working voltage.

3.2 Surge Voltage Test: capacitors shall withstand the

surge voltage applied through a 1000

 ± 10 % resistor

in series with the capacitor and voltage source at the

rate of one-half minute on, five and one-half minutes off,

for 1000 successive test cycles at +85 °C.

3.3 Following the surge voltage test, the capacitance at

+25 °C shall not have changed by more than ± 10 % and

the equivalent series resistance and DC leakage current

will not exceed the values shown in the Standard

Ratings table for each capacitor.

4.

Capacitance

Tolerance:

the

capacitance

of

all

capacitors shall be within the specified tolerance limits

of the nominal rating.

4.1 Measurements shall be made by the bridge method at

or referred to a frequency of 120 Hz at a temperature of

+25 °C. The maximum voltage applied to the capacitors

accuracy of the bridge shall be within ± 2 %.

5.

Capacitance

Change

With

Temperature:

the

capacitance change with temperature shall not exceed

the values given in the Standard Ratings table for each

capacitor.

6.

Equivalent Series Resistance: measurements shall be

made by the bridge method at, or referred to, a

frequency of 120 Hz at a temperature of +25 °C. A

maximum

of

1

measurement.

6.1 The equivalent series resistance shall not exceed the

maximum value in ohms listed in the Standard Ratings

table for each capacitor.

6.2 The dissipation factor may be calculated from the

equivalent series resistance and capacitance values as

shown:

where:

DF = dissipation factor in %

R = ESR in



C = capacitance in μF

f = frequency in Hz

At 120 Hz, the above equation becomes:



For example, percent dissipation factor of a 30 μF, 6 V

capacitor, which has a maximum ESR of 4.0

 at

+25 °C and 120 Hz, would be calculated as shown:



7.

Leakage Current: measurements shall be made at the

applicable rated working voltage at +25 °C ± 5 °C

through application of a steady source of power, such

as a regulated power supply. A 1000

 resistor to limit

the charging current shall be connected in series with

each capacitor under test. Rated working voltage shall

be applied to capacitors for 5 minutes before making

leakage current measurements.

TYPICAL CURVES OF IMPEDANCE AS A FUNCTION OF FREQUENCY AT VARIOUS TEMPERATURES

0.1

1.0

10

100

100

1K

10K

100K

1M

10M

“C” Case 50 V Capacitors

+125 °C

+25 °C

-40 °C

-55 °C

-20 °C

+85 °C

Frequency (Hz)

UP TO +85 °C

(V)

AT +125 °C

(V)

50

30

75

50

100

65

125

85

DF

2

fRC

10

4

------------------

=

DF

13.26

---------------

=

DF

2

10

4

----------------------------------------------

13.26

----------------

9.05 %

==

=