| 1. Scope of the coverage¡G |
| ¡@This specification is pertinent to the application
of fixed metal oxide resistors (designated as RS). |
| 2 .Temperature range of the application¡G |
| ¡@-55¢J ¡ã +155¢J¡C |
| 3. Type¡G |
| ¡@Two types of fixed metal oxide resistors
are available, one is normal size and the other one
is |
| ¡@small size. These two types are distinguished by
the color of the coating resin. The color of the |
| ¡@resin for the normal size is gray and that for the
small size is pinkish red. |
| 4.Marking and illustration¡G |
| ¡@Two types of designation methods are available for
metal oxide resistors. One is black ink |
| ¡@alphanumeric marking and the other one is color code
marking. The criteria of using either one of |
| ¡@the marking methods depend on the size of the resistors
and customers request which is listed in |
| ¡@the following: |
| ¡@alphanumeric marking ¡÷1/2W¡B1W¡B2W¡B3W¡BS1W¡BS2W¡BS3W¡BS5W¡BS7W
(Fig.1) |
| ¡@color code marking ¡÷1/4W¡BS1/2W (Fig.2) (Larger sizes
are available upon request) |
¡@ (Fig.1) |
¡@ (Fig.2) |
| ¡@Illustration of color codes¡G |
|
|
1-st Band
(Sig. digit)
|
2-nd Band
(Sig. digit)
|
3-rd Band
(Multiplier)
|
4-th Band
(Tolerance)
|
|
Black
|
0
|
0
|
1
|
.
|
|
Brown
|
1
|
1
|
10
|
¡Ó1%
|
|
Red
|
2
|
2
|
100
|
¡Ó2%
|
|
Orange
|
3
|
3
|
1000
|
.
|
|
Yellow
|
4
|
4
|
10000
|
.
|
|
Green
|
5
|
5
|
100000
|
¡Ó0.5%
|
|
Blue
|
6
|
6
|
1000000
|
¡Ó0.25%
|
|
Purple
|
7
|
7
|
10000000
|
¡Ó0.1%
|
|
Gray
|
8
|
8
|
.
|
¡Ó0.05%
|
|
White
|
9
|
9
|
.
|
.
|
|
Gold
|
.
|
.
|
0.1
|
¡Ó5%
|
|
Silver
|
.
|
.
|
0.01
|
¡Ó10%
|
|
| ¡@ |
| 5.Dimension, voltage, resistance range: listed
in the following table |
|
Rated
Power
W
|
Type
|
Resistance
Range
£[
|
Higest
Working
Voltage
V
|
Higest
Overload
Voltage
V
|
 2
|
|
J ( ¡Ó5%)
|
L
|
D£r
|
£d
|
d£r
|
|
1/4
|
Normal
|
0.1¡ã910K
|
250
|
500
|
6¡Ó0.3
|
2.4¡Ó0.1
|
28¡Ó2
|
0.6¡Ó0.05
|
|
1/2
|
Small
|
0.1¡ã910K
|
250
|
500
|
6¡Ó0.3
|
2.4¡Ó0.1
|
28¡Ó2
|
0.6¡Ó0.05
|
|
Normal
|
0.1¡ã470K
|
250
|
500
|
9¡Ó0.5
|
3.0¡Ó0.5
|
30¡Ó3
|
0.6¡Ó0.05
|
|
1
|
Small
|
0.1¡ã470K
|
350
|
600
|
9¡Ó0.5
|
3.0¡Ó0.5
|
30¡Ó3
|
0.8¡Ó0.05
|
|
Normal
|
0.1¡ã750K
|
350
|
700
|
|
4.0¡Ó0.5
|
38¡Ó3
|
0.8¡Ó0.05
|
|
2
|
Small
|
0.1¡ã750K
|
350
|
700
|
|
4.0¡Ó0.5
|
38¡Ó3
|
0.8¡Ó0.05
|
|
Normal
|
0.1¡ã330K
|
350
|
700
|
|
5.5¡Ó0.5
|
38¡Ó3
|
0.8¡Ó0.05
|
|
3
|
Small
|
0.1¡ã330K
|
350
|
700
|
|
5.5¡Ó0.5
|
38¡Ó3
|
0.8¡Ó0.05
|
|
Normal
|
0.1¡ã100K
|
500
|
1000
|
|
8.5¡Ó0.5
|
38¡Ó3
|
0.8¡Ó0.05
|
|
5
|
Small
|
0.1¡ã100K
|
500
|
1000
|
|
8.5¡Ó0.5
|
38¡Ó3
|
0.8¡Ó0.05
|
|
Small
|
0.1¡ã47K
|
500
|
1000
|
For erect H type resistor (H15¡BH25)
|
|
7
|
Small
|
0.1¡ã10K
|
500
|
1000
|
For erect F type resistor |
|
| ¡@ |
| 6.Coating |
¡@ |
| ¡@6.1 The body of the resistor is covered by nonflammable
silicon resin. |
| ¡@6.2 The maximum length of the lead wire covered by
the resin is 2mm. |
| ¡@6.3 The maximum area of the end cap which is not
covered by the resin is half of the diameter of |
| ¡@the cap. |
| ¡@6.4 The status of coating condition described by
6.2 and 6.3 are acceptable. |
| ¡@ |
| 7.Characteristics of electrical performance |
| ¡@7.1 Rated power |
| ¡@The rated power indicates the maximum power the resistor
can endure continuously when the |
| ¡@ambient temperature is equal to or lower than 70¢J.
When the ambient temperature is higher than |
| ¡@70¢J, the rated power of the resistor is determined
by the derating curve described in the following |
| ¡@figure. |
| ¡@ |
¡@
|
| ¡@7.2 Rated voltage |
| ¡@The rated voltage of a resistor is either a continuous
DC voltage or an AC rms voltage which can be |
| ¡@calculated by the following formula. If the calculated
rated voltage is higher than the highest |
| ¡@working voltage then the highest working voltage
should be used as the rated voltage. |
¡@ ¡@P:
Rated power(W)¡@R: Nominal resistance(£[)¡@E: Rated voltage(V) |
| ¡@ |
| ¡@7.3 Insulation resistance (Ref. JIS C5202
5.6) |
| ¡@Equipment: Insulation resistance tester |
| ¡@The body of the resistor is wrapped around by the
aluminum foil without extending beyond the |
| ¡@resistor body. Clap one electrode on the aluminum
foil and the other electrode on the lead wire. |
| ¡@Apply 100V or 500V from the tester for 1 min. and
the measured resistance value should be larger |
| ¡@than 1,000MW. |
| ¡@ |
| ¡@7.4 Dielectric strength (Ref. JIS C5202 5.7) |
| ¡@Equipment: Dielectric strength tester |
| ¡@The body of the resistor is wrapped around by the
aluminum foil without extending beyond the |
| ¡@resistor body. Clap one electrode on the aluminum
foil and the other electrode on the lead wire. |
| ¡@Apply following voltage from the tester to the resistor
for 1 min.. No flash-over, burning or |
| ¡@breakdown should be observed. |
|
|
1/4
|
1/2
|
1
|
2
|
3
|
5
|
7
|
|
Normal
|
250V
|
250V
|
350V
|
350V
|
500V
|
----
|
----
|
|
Small
|
----
|
250V
|
350V
|
350V
|
350V
|
500V
|
----
|
|
Erect type
|
----
|
----
|
----
|
----
|
----
|
800V
|
800V
|
|
| ¡@ |
| ¡@7.5 Short time overload (SOL) (Ref. JIS C5202 5.5) |
| ¡@Equipment: S.O.L. tester. |
| ¡@Apply 2.5 times of rated voltage to the resistors
for 5 seconds. If the applied voltage is larger than
|
| ¡@the voltage listed in the following table, then the
voltage in the table should be used instead. After |
| ¡@the test, the sample should be stabilized at room
temperature for 30 min. before the resistance is |
| ¡@measured. The change of the resistance before and
after the test should be: normal size: |
| ¡@(1%+0.05£[); small size: ¡Ó(2%+0.1£[). |
| ¡@ |
|
|
1/4
|
1/2
|
1
|
2
|
3
|
5
|
7
|
|
Normal
|
500V
|
500V
|
700V
|
700V
|
1000V
|
----
|
----
|
|
Small
|
----
|
500V
|
600V
|
700V
|
700V
|
1000V
|
----
|
|
Special(Erect)
|
----
|
----
|
----
|
----
|
----
|
1000V
|
1000V
|
|
| ¡@ |
| ¡@7.6 Intermittent overload (Applicable for nominal
resistance larger than 100£[) (Ref. JIS C5202 5.8) |
| ¡@Equipment: Intermittent tester |
| ¡@First put the resistor to the environment chamber
at 55¡Ó2¢J and relative humidity at 20% for 24 |
| ¡@hours. After that, take the resistor out and stabilize
it at room temperature for 30 min. Measure the |
| ¡@resistance before the test. Put the resistor to a
horizontal position and a distance of 50mm from |
¡@each other. Apply 4 times of rated voltage with a
cycle of 1 sec. ON and 25 sec. OFF for
|
| ¡@cycles. After that, take out the resistor and let
it rest at room temperature for 30 min. and then |
| ¡@measure the resistance. The acceptable % change of
resistance is: normal size: ¡Ó(2%+0.1£[); |
| ¡@small size: ¡Ó(5%+0.1£[). The maximum applied voltage
should not exceed the value listed in the |
| ¡@following table: |
|
|
1/4
|
1/2
|
1
|
2
|
3
|
5
|
7
|
|
Normal
|
500V
|
500V
|
750V
|
750V
|
1500V
|
----
|
----
|
|
Small
|
----
|
500V
|
750V
|
750V
|
750V
|
1500V
|
----
|
|
Special(Erect)
|
----
|
----
|
----
|
----
|
----
|
1500V
|
1500V
|
|
| ¡@ |
| ¡@7.7 Flame proof (Ref. JIS C5202 7.12 3.4(2)c) |
| ¡@Equipment: AC power supply |
| ¡@Apply 2 times, 4 times, 8 times, 16 times
and 32 times of rated voltage sequentially. The duration
|
| ¡@for each voltage application is 1 min..
The resistor should not demonstrate arcing, burning
or melt |
| ¡@down except when the applied voltage exceeds
10 times of rated power. Under this circumstance |
| ¡@of applied more than 10 times of rated
power, arcing or burning is acceptable but the duration
|
| ¡@should be less than 5 sec. And the height
of flame should be less than 3.5mm. The maximum |
| ¡@applied voltage should not exceed 4 times
of the value listed in the following table: |
|
|
1/4
|
1/2
|
1
|
2
|
3
|
5
|
7
|
|
Normal
|
250V
|
250V
|
350V
|
350V
|
500V
|
----
|
----
|
|
Small
|
----
|
250V
|
350V
|
350V
|
350V
|
500V
|
----
|
|
Special(Erect)
|
----
|
----
|
----
|
----
|
----
|
500V
|
500V
|
|
| ¡@ |
| 8.Environmental tests |
| ¡@8.1 Load life test (Endurance with rated load) (Ref.
JIS C5202 7.10) |
| ¡@Equipment: High temperature chamber and DC power
supply |
| ¡@The resistors are put in a fixture where no interference
will be allowed. Put the fixture in a 70¡Ó3¢J |
¡@chamber and apply rated voltage with a
cycle of 90 min. ON and 30 min. OFF for
hours. |
| ¡@After 240, 480, 720 and 1,000 hours, the resistors
are taken out and stabilize at room temperature |
| ¡@for 30 min. and then the resistance is measured.
Upon each step of resistance measurement, the |
| ¡@change of the resistance should not exceed ¡Ó(5%+0.1£[)
and the appearance should show no |
| ¡@remarkable abnormality and legibility of marking. |
| ¡@ |
| ¡@8.2 Resistance to cold (Ref. JIS C5202 7.1) |
| ¡@Equipment: Constant temperature and humidity chamber |
| ¡@Put the resistors to the chamber with -40¡Ó2¢J, RH=90¡ã95%
for 240¡Ó4 hours. Take them out and |
| ¡@ put them in room temperature for 1¡ã4 hours then
measure the resistance. The acceptable |
| ¡@change of resistance should not exceed ¡Ó(1%+0.05£[)
and the appearance should show no |
| ¡@remarkable abnormality and legibility of marking. |
| ¡@ |
| ¡@ 8.3 Endurance under damp heat and load (Ref. JIS
C5202 7.9) |
| ¡@Equipment: Constant temperature and humidity chamber,
DC power supply |
| ¡@The resistors are put in a fixture where no interference
will be allowed. Put the fixture in a 40¡Ó2¢J |
| ¡@chamber with RH=90¡ã95% and apply rated voltage with
a cycle of 90 min. ON and 30 min. OFF for |
| ¡@
hours. Water drops should avoid dripping on the resistors.
After 240 and 1,000 hours, the |
| ¡@resistors are taken out and stabilize at room temperature
for 1 hour and then the resistance is |
| ¡@measured. Upon each step of measurement, the change
of the resistance should not exceed |
| ¡@¡Ó(5%+0.1£[) and the appearance should show no remarkable
abnormality and legibility of marking. |
| ¡@ |
| ¡@8.4 Temperature coefficient (TCR) (Ref. JIS C5202
5.2) |
| ¡@Equipment: High temperature chamber |
| ¡@Measure the resistance at room temperature. Put the
resistor in a chamber with the temperature of |
| ¡@RT+100¢J for 30 - 45 min. to stabilize. Measure the
resistance again. Compare the resistance at |
| ¡@these two temperatures with the following equation
and the acceptable value is ¡Ó350 PPM/¢J. |
¡@ |
| ¡@R = Resistance at T ¡@T = RT + 100¢J¡@Ro = Resistance
at To¡@To =room temperature |
| |
| ¡@8.5 Temperature cycling (Ref. JIS C5202 7.4) |
| ¡@Equipment: High temperature chamber, low temperature
chamber |
| ¡@Measure the resistance before the test. Put the resistor
to -55¢J chamber for 30 min. then take it |
| ¡@out at room temperature for 2 to 3 min.. Put the
resistor to +155 ¢Jchamber for 30 min. then take it |
| ¡@out at room temperature for 2 to 3 min. This completes
a cycle. Repeat the cycle 5 times. Put |
| ¡@resistors at room temperature for 90 min. and then
measure the resistance. Compare the |
| ¡@resistance before and after test. The acceptable
change of resistance is ¡Ó(1%+0.05£[). The |
| ¡@appearance should show no remarkable abnormality
and legibility of marking. |
| ¡@ |
| ¡@8.6 Low temperature storage (Ref. JIS C5202 7.1) |
| ¡@Equipment: Low temperature chamber |
| ¡@Stabilize the resistor at room temperature for 30
min. then measure the resistance. Put the |
| ¡@resistors into the chamber and gradually lower the
temperature to -55¡Ó3¢J and maintain at that |
| ¡@temperature for 24+4-0 hours. Gradually raise the
temperature of the chamber to room |
| ¡@temperature and then take resistors out and stabilize
at room temperature for 1 to 2 hours. |
| ¡@Measure the resistance value. The change of the resistance
before and after the test should be |
| ¡@less than ¡Ó(1%+0.05£[). The appearance should show
no remarkable abnormality and legibility of |
| ¡@marking. |
| ¡@ |
| ¡@8.7 Resistance to heat (Ref. JIS C5202 7.2) |
| ¡@Equipment: High temperature chamber |
| ¡@Measure the resistance at room temperature. Put the
resistors to 200¢J chamber for 2 hours. |
| ¡@Take resistors out and stabilize at room temperature
for 1 hour. Measure the resistance value. The |
| ¡@change of the resistance before and after the test
should be less than ¡Ó(2%+0.1£[). The |
| ¡@appearance should show no remarkable abnormality
and legibility of marking. |
| ¡@ |
| 9.Mechanical performance |
| ¡@9.1 Resistance to soldering heat (Ref. JIS C5202
6.4) |
| ¡@Equipment: Solder bath |
| ¡@Measure the resistance before the test. Immerse part
of the lead wire which is 4¡Ó0.8mm away from |
| ¡@the body to the flux for 5 - 10 sec. Take the resistor
out and immerse resistors in the solder bath of |
| ¡@350¡Ó10¢J for 3.5¡Ó0.5 sec.. Stabilize at room temperature
for 1 hour and then measure the |
| ¡@resistance value. Compare the resistance values before
and after the test, The acceptable change |
| ¡@is ¡Ó(1%+0.05£[). |
| ¡@ |
| ¡@9.2 Solderability (Ref. JIS C5202 6.5) |
| ¡@Equipment: Solder bath |
| ¡@Immerse part of the lead wire which is 4¡Ó0.8mm away
from the body to the flux for 5 - 10 sec. Take |
| ¡@the resistor out and immerse resistors
in the solder bath of 245¡Ó5¢J for 3.5¡Ó0.5 sec.. Take
the |
| ¡@resistor out and inspect the lead wire visually.
The acceptable level is the coverage of the new |
| ¡@solder to be 95%. The composition of the solder bath
is 99.7% tin and 0.3% Cu. |
| ¡@ |
| ¡@9.3 Robustness of terminals (Ref. JIS C5202 6.1) |
| ¡@9.3.1 Tensile strength of termination |
| ¡@Equipment: Weight gauge |
| ¡@Fixed the resistor and apply axially along the lead
wire of 2.5Kg (0.8£p lead wire) or 1.0Kg (0.6£p lead |
| ¡@wire) for 30 sec.. The lead wire should not break
or detached from the resistor and the change of |
| ¡@the resistance should be less than ¡Ó(0.5%+0.05£[). |
| ¡@ |
| ¡@9.3.2 Torsional strength |
| ¡@Equipment: Torsion tester |
| ¡@Bend the terminal 6.4mm away from the body according
to Fig-a to 90 degree with a curvature of |
| ¡@0.75mm¡ã0.80mm. The lead wire should be clamped at
a point of 1.2mm away from the bending |
| ¡@point by a fixture which can rotate 360 degree according
to Fig-b. Rotate the resistor 360 degree |
| ¡@clockwise and counter clockwise for 1 cycle. The
rotation speed is 360 degree per 5 sec.. Perform |
| ¡@3 cycles for the lead wire diameter of 0.8£p and 1.5
cycles for that of 0.6£p. The terminal should not |
| ¡@break down or detached from the body. The acceptable
change of resistance is ¡Ó(0.5%+0.05£[). |
¡@ ¡@¡@¡@ |
