| 1. Scope of the coverage： |
| This specification is pertinent to the
application of metal glaze resistors (designated as RM). |
| 2 .Temperature range of the application： |
| -55℃ ～ +155℃。 |
| 3.Marking and illustration： |
| Two types of designation methods are
available for metal glaze resistors. One is black ink |
| alphanumeric marking and the other one is
color code marking. |
| alphanumeric marking
---->1/2W、1W、2W、S1W、S2W、S3W (Fig.1) |
| color code marking
---------------->1/6W、 S1/4W、1/4W、S1/2W (Fig.2) |
| |
| The color of flame proof resin coating is
pinkish red for the following types of resistors: (1/2W |
| 、1W、2W 、S1W、S2W、S3W). Other type of resin
and the corresponding color is also listed: |
| Blue epoxy resin (1/6W、1/4W). |
| Pinkish red epoxy resin (S1/4W、S1/2W) |
| |
| Illustration of color codes： |
|
5%
Designation
|
1-st Band
(Sig. digit)
|
2-nd Band
(Sig. digit)
|
|
3-rd Band
(Multiplier)
|
4-th Band
(Tolerance)
|
|
|
1-st Band
(Sig. digit)
|
2-nd Band
(Sig. digit)
|
3-rd Band
(Sig. digit)
|
4-th Band
(Multiplier)
|
5-th Band
(Tolerance)
|
|
Black
|
0
|
0
|
0
|
1
|
.
|
|
Brown
|
1
|
1
|
1
|
10
|
±1%
|
|
Red
|
2
|
2
|
2
|
100
|
±2%
|
|
Orange
|
3
|
3
|
3
|
1000
|
.
|
|
Yellow
|
4
|
4
|
4
|
10000
|
.
|
|
Green
|
5
|
5
|
5
|
100000
|
±0.5%
|
|
Blue
|
6
|
6
|
6
|
1000000
|
±0.25%
|
|
Purple
|
7
|
7
|
7
|
10000000
|
±0.1%
|
|
Gray
|
8
|
8
|
8
|
.
|
±0.05%
|
|
White
|
9
|
9
|
9
|
.
|
.
|
|
Gold
|
.
|
.
|
.
|
0.1
|
±5%
|
|
Silver
|
.
|
.
|
.
|
0.01
|
±10%
|
|
| |
| 4.Illustration of color codes |
|
|
Resistance
Range
(Ω)
|
Highest Working Voltage
(V)
|
 2 |
|
L
|
Dψ
|
ι
|
dψ
|
|
1/6、S1/4
|
1K～100M
|
500
|
3.3 ±0.3
|
1.8±0.2
|
28±2
|
0.45±0.05
|
|
1/4、S1/2
|
1K～100M
|
1600
|
6±0.3
|
2.4±0.1
|
28±2
|
0.6±0.05
|
|
1/1、S1
|
1K～100M
|
3500
|
9±0.5
|
3.3±0.5
|
30±3
|
0.6±0.05
|
|
1、S2
|
1K～100M
|
3500
|
|
4.5±0.5
|
38±3
|
0.8±0.05
|
|
2、S3
|
1K～100M
|
3500
|
|
5.5±0.5
|
38±3
|
0.8±0.05
|
|
| |
| 5.Coating |
| |
| 5.1 The maximum length of the lead wire
covered by the resin is 1mm |
| 5.2 The maximum area of the end cap which
is not covered by the resin is half of the diameter of |
| 5.2 the cap. |
| 5.3 The status of coating condition
described by 5.1 and 5.2 are acceptable. |
| |
| 6.Characteristics of electrical
performance |
| 6.1 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℃. When the ambient temperature is higher than |
| 70℃, the rated power of the resistor is
determined by the derating curve described in the following |
| figure. |
| |
| 6.2 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(Ω) E: Rated voltage(V) |
| |
| 6.3 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 500V from the tester for 1 min. and
the measured resistance value should be larger than |
| 1,000MW. |
| |
| 6.4 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. |
|
W
|
1/6、S1/4
|
1/4、1/2、1、2、S1/2、S1、
S2、S3
|
|
Dielectric strength
|
300V
|
700V
|
|
| |
| 6.5 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-2, 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 acceptable change of the
resistance before and after the test is listed in Table-1. |
| |
|
W
|
1/6、S1/4
|
1/4、1/2、1、2、S1/2、S1、
S2、S3
|
|
Acceptable change
|
±(1%+0.05Ω)
|
±(0.5%+0.05Ω)
|
|
| (Table-1) |
|
W
|
1/6、S1/4
|
1/4、1/2、1、2、S1/2、S1、
S2、S3
|
|
Voltage
|
1000V
|
1500V
|
|
| (Table-2) |
| |
| 6.6 Intermittent overload (Ref. JIS C5202
5.8) |
| Equipment: Intermittent tester |
| First put the resistor to the
environment chamber at 55±2℃ 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：±(1%+0.1Ω)The voltage |
| applied should not exceed the
value listed in the following table. |
|
W
|
1/6、S1/4
|
1/4、1/2、1、2、S1/2、S1、
S2、S3
|
|
Voltage
|
1000V
|
1500V
|
|
| |
| 6.7 Pulse test |
| Equipment: Pulse tester |
| Arrange the sample (Rx)
according to the following diagram. Apply DC:10KV, 0.001μF capacitor. |
| One charge-discharge cycle is 5
sec. Continue 50 cycles. After the test, take the sample out and |
| stabilize at room temperature
for 30 min.. Measure the resistance before and after the test. The |
| acceptable change is±20%. the
appearance should show no remarkable abnormality and |
| legibility of marking. During
the test, no arcing should be observed. |
 - |
| |
| 7.Environmental tests |
| 7.1 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±3℃ |
| 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 ±(1.5%+0.1Ω) and the appearance should show |
| no remarkable abnormality and legibility
of marking. |
| |
| 7.2 Resistance to damp heat (Ref. To JIS
C5202 7.2) |
| Equipment: Constant temperature and
humidity chamber |
| The resistors are put in a 40±2℃ chamber
with RH=90～95% for 240±4 hours. After the test, take |
| the resistors out and stabilize in room
temperature for 1 - 4 hour. Measure the resistance. The |
| acceptable change of resistance should not
exceed ±(2%+0.1Ω) and the appearance should |
| show no remarkable abnormality and
legibility of marking. |
| |
| 7.3 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±2℃ |
| chamber with RH=90～95% 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 |
| ±(5%+0.1Ω) and the appearance should show
no remarkable abnormality and legibility of marking. |
| |
| 7.4 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℃ 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: |
| < 100K±300 PPM/℃ or ≧100K±200 PPM/℃. |
 |
| R = Resistance at T T = RT + 100℃ Ro =
Resistance at To To =room temperature |
| |
| 7.5 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℃ chamber for 30 min. then take it |
| out at room temperature for 2 to 3 min..
Put the resistor to +155 ℃chamber 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 ±(1%+0.05Ω). The |
| appearance should show no remarkable
abnormality and legibility of marking. |
| |
| 7.6 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±3℃ and maintain at that |
temperature for 
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 |
| ±(1%+0.05Ω). The appearance should show no
remarkable abnormality and legibility of marking. |
| (Remove any water condensation on the
resistor body during the test) |
| |
| 8.Mechanical performance |
| 8.1 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±0.8mm away from |
| the body to the flux for 5 - 10 sec. Take
the resistor out and immerse resistors in the solder bath of |
| 350±10℃ for 3.5±0.5 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 ±(1%+0.05Ω). |
| |
| 8.2 Solderability (Ref. JIS C5202 6.5) |
| Equipment: Solder bath |
| Immerse part of the lead wire which is
4±0.8mm away from the body to the flux for 5 - 10 sec. Take |
| the resistor out and immerse
resistors in the solder bath of 245±5℃ for 3.5±0.5 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. |
| |
| 8.3 Robustness of terminals (Ref. JIS
C5202 6.1) |
| 8.3.1 Tensile strength of termination |
| Equipment: Weight gauge |
| Fixed the resistor and apply
axially along the lead wire of 2.5Kg (0.8φ lead wire), 1.0Kg (0.6φ lead
|
| wire) or 0.5Kg (0.45φ 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 ±(0.5%+0.05Ω). |
| |
| 8.3.2 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～0.80mm. 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
0.8φ, 1.5 cycles for that of 0.6φ and 1 cycle for that of 0.45φ. |
| The terminal should not break
down or detached from the body. The acceptable change of |
| resistance is ±(0.5%+0.05Ω). |
  |
