SPECIFICATION
528 Series
CAPACITANCE:
When measured at
room temperature (25°C ± 5°C) and at
a frequency of 0.1 to 1 megahertz, the
minimum capacitance shall not be
greater than that specified at minimum
setting with a +10% tolerance, and
the maximum capacitance shall not
be less than that specified at maximum
setting with a -10% tolerance.
"Q" FACTOR:
When measured at
room temperature (25°C ± 5°C), at a
frequency of approximately 1 mega-
hertz, the capacitor at approximately
maximum rated capacitance setting
shall have a "Q" value not less than
indicated for the respective style.
INSULATION RESISTANCE:
The
insulation resistance at approximately
maximum capacitance setting shall be
10 gigaohms minimum at room temper-
ature of (25°C ± 5°C) when measured
at 100 volts dc in a series with a protec-
tive resistance not exceeding 1 mega-
ohm after no more than one minute
application of the voltage.
DIELECTRIC STRENGTH:
The
capacitor, set at approximately maxi-
mum capacitance shall withstand volt-
age between terminals for 1 to 5 sec.
as indicated for the respective style.
(50mA maximum charging current)
TORQUE:
When measured at room
temperature (25°C ± 5°C), the torque
required to start and maintain rotation
of the rotor through one full turn, shall
be as indicated for the respective style.
TEMPERATURE CHARACTERISTIC:
The temperature characteristic of
capacitance shall be within the limits
shown in the following table. The
temperature characteristic shall be
determined by measuring the capaci-
tance (capacitor shall be set at approx-
imately 75% of the guaranteed maxi-
mum capacitance) +25°C, -55°C,
and either +85°C or +125°C, which-
ever is applicable to the respective
style, at a frequency of 0.1 to 1
megahertz. Each measurement shall
be made after the capacitor has
reached thermal stability.
CAPACITANCE DRIFT:
With the
capacitor set at approximately 75%
of the guaranteed maximum capaci-
tance, the capacitance drift shall be
determined as the greatest difference
between any two of three 25°C mea-
surements, when temperature cycled
as follows: +25°C, -55°C, +85°C or
+125°C, whichever is applicable to
respective style, +25°C. The capaci-
tance drift shall not exceed 0.75% or
0.5ρF, whichever is greater.
ACCELERATED LIFE TEST:
The
capacitor, at approximately 75% of
the guaranteed maximum capaci-
tance, shall be tested for 250 hours at
twice rated voltage, and at a tempera-
ture equal to the maximum operating
temperature ±3°C for the respective
style. At the end of this period the
capacitance shall not have changed
more than ±5% of its value before the
life test or ±0.5ρF, whichever is great-
er; the insulation resistance shall be 1
gigaohm minimum and the "Q" at 1
megahertz shall be at least 40% of the
initial test limit.
TEMPERATURE CYCLING &
HUMIDITY:
The capacitor, at approx-
imately 75% of the guaranteed maxi-
Ceramic
Trimmer Capacitors
mum capacitance, shall be given a
treatment consisting of 5 temperature
cycles as follows: Cool capacitor
to -55°C ±3°C. Remove the capaci-
tor from the cooling chamber and allow
it to reach room temperature. Then
place in an oven at a temperature
equal to maximum operating tempera-
ture ±3°C of the respective style.
Remove from oven and allow capaci-
tor to cool to room temperature. The
capacitor shall be held at the specified
minimum and maximum temperatures
long enough to reach equilibrium, and
in no case less than 15 minutes. The
rate of change of temperature in cool-
ing from room temperature, or heating
above it, shall not be less than 3°C
per minute. The temperature cycles
shall be followed by exposure for 96
hours to a relative humidity of 95% at
40°C ±3°C. The capacitor shall then
be removed from the humidity cham-
ber and held at 25°C ±5°C with a
maximum humidity of 50% for four
hours. The insulation resistance shall
be at least 1 gigaohm, the "Q" at 1
MHZ is at least 40% of initial test limit
and the capacitance shall not have
changed by more than ±3% or
±0.5ρF, whichever is greater, from its
value prior to the start of the
temperature cycling.
Dielectic
Type Code
A
C
E
F
G
PERCENT CAPACITANCE CHANGE
FROM VALUE @ 25°C
+125°C
-55°C
+85°C
Min.
Min.
Min.
Max.
Max.
Max.
-4.5
-1.0
+1.75
+6.0
0.0
+2.0
+6.5
+8.0
+16.0
+14.0
-2.5
-4.0
-5.75
-11.0
-8.0
+2.0
-1.0
-1.75
-6.0
-3.0
-4.2
-6.7
-9.5
-15.0
-14.0
+3.4
-1.7
-2.8
-9.0
-5.0
模拟电子
