Characteristics |
Test Methods |
Limits |
D C Resistance |
Resistors are tested with standard specified voltages for its Ohmic values to check the specified tolerance. |
The Resistors shall be within specified tolerance limits. |
Short Time Overload |
The Resistors shall be subjected to 2.5 times the Rated Voltage or Maximum overload voltage (whichever is low) for a duration of 5 secs. |
? R % = ± 0.5% (+ 0.05 ?) |
Temp - Coefficient |
The Resistors value shall be checked at 2 temp. i.e. one At Ambient & the final at Amb + 100? C. The TCR is then Calculated as :
|
PPM |
25 PPM /?C |
50 PPM /?C |
100 PPM /?C |
200 PPM / ?C |
Rated Load |
A Rated Continuous Working Voltage or Maximum Wkg. Voltage whichever less shall be applied to the resistors for a duration of 2 Hrs. |
? R % = ± 0.5% Max |
Solderability |
A solder bath is maintained at 230? C. The specimen leads are immersed in the bath & withdrawn within 3 secs. A suitable flux is used during the test. |
A fresh solder shall cover the specimen leads by Min. 95% coverage. |
Resistance to solder heat |
A solder bath is maintained at 350? C. The specimen leads are subjected to the bath for a duration of 10 secs. |
? R % = ± 1 % Max |
Resistance to Solvents |
The specimen shall be subjected to IPA for duration of 1 min. 10 strokes of hard brush shall be applied. The test shall be conducted 3 times. |
The colour code marking shall remain legible. |
Die-electric Strength |
A foil is wrapped around the specimen body. A voltage of 300 V @ 0.5 ma shall be applied between both the terminals of the specimen for a duration of 1 min. |
There shall be no flash over or break down. |
Terminal Strength |
Pull Test: The resistors leads shall be pulled using 5 N force Bend Test: The resistor leads are bend through 180? three times. |
There shall be no damage. |
Load Life |
The specimen shall be subjected to an ambient of 70?C for duration of 1000 Hrs. The specimen shall also be loaded for full power dissipation. The duty cycle shall be 1½ Hr. On ½ Hr. Off. |
? R % = ± 2 % Max |
Steady State Humidity |
The shall be subjected to an amb. Of 40?C with RH as 95%, for a duration of 56 days. A small DC voltage shall be so applied that the specimen shall dissipate 1% of the rated power. |
? R % = ± 2 % Max |