Test Methods
*RCWV = Rated Continuous Working Voltage = Rated Power x Resistance Value
Characteristics Limits
DC. Resistance Must be within the specified tolerance 5.1 The limit of error of measuring apparatus shall not exceed
allowable range or 1% of resistance tolerance
Temperature coefficient
5.2 Natural resistance change per temp. degree centigrade.
R1: Resistance value at room temperature (t1)
R2: Resistance value at room temp. plus 100°C (t2)
R1(t2-t1)
R2-R1x 106 (PPM/°C)
±50 PPM/°C Maximum
Within the temperature coefficient
specified below:
Short time overload 5.5 Permanent resistance change after the application of
a potential of 2.5 times RCWV for 5 seconds
Resistance change rate is
±(0.5% +0.05Ω) Max. with No
evidence of mechanical damage.
Pulse overload 5.8 Resistance change after 10,000 cycles (1 second "ON",
25 seconds "OFF") at 4 times RCWV
Resistance change rate is
±(1% +0.05Ω) Max. with no evidence
of mechanical damage.
Dielectric withstanding
voltage 5.7 Resistors shall be clamped in the trough of a 90° metallic
V-block and shall be tested at AC potential respectively
specified in sheet '1'
No evidence of flashover mechanical
damage, arcing or insulation
breakdown.
Terminal strength
6.1Direct load:
Resistance to a 2.5 kgs direct load for 10 seconds in the
direction of the longitudinal axis of the terminal leads.
Twist test:
Terminal leads shall be bent through 90° at a point of about
6mm from the body of the resistor and shall be rotated through
360° about the original axis of the bent terminal in alternating
directions for a total of 3 rotations.
No evidence of mechanical damage.
Resistance to soldering
heat 6.4 Permanent resistance change when leads immersed to
3.2 to 4.8mm from the body in 350°C ±10°C solder for 3 ±0.5
seconds.
Resistance change rate is
±(1% +0.05Ω) Max. with no evidence
of mechanical damage.
Solderability 6.5 The area covered with a new, smooth, clean, shiny and
continuous surface free from concentrated pinholes.
Test temperature of solder: 245°C ±3°C
Dwell time in solder: 2-3 seconds
95% coverage Min.
Resistance to solvent 6.9 Specimens shall be immersed in a bath of trichroethane
completely for 3 mins with ultrasonic.
No deterioration of protective coating
and markings.
Temperature cycling
7.4 Resistance change after continuous five cycles for duty shown
below :
10 ~ 15Room Temp.4
10 ~ 15
Time (min)
-55°C ±3°C
Room Temp.
+155°C ±2°C
Temperature
1
2
3
Step 30
30
Resistance change rate is
±(1% +0.05Ω) Max. with no evidence
of mechanical damage.
Load life in humidity 7.9 Resistance change after 1,000 hours (1.5 hours "ON, 0.5 hour
"OFF" ) at * RCWV in humidity test chamber controlled at
40°C±2°C and 90 to 95% relative humidity.
Resistance Value
Normal type
∆R/R
±1.5%
Load life 7.10 Permanent resistance change after 1,000 hours operating at
* RCWV with duty cycle of 1.5 hours "on", 0.5 hour "off"
at 70°C ±2°C ambient.
Resistance Value
Normal type
∆R/R
±1.5%
(JIS C 5201-1)