Presentation at 2013 RAMS with focus on case study of life testing for new product in storage.

1. Accelerated Testing
for 2-year Storage
Fred Schenkelberg
OPS A LA CARTE
990 Richard Avenue, Santa Clara 95054
(408)710-8248
fms@opsalacarte.com
RAMS 2013

3. cylindar
block
Epoxy

4. cylinder
block
Activation
Energy?
Epoxy

6. Low
Medium
High
Arrhenius model and
Inverse power law model
Temperature-Nonthermal Weibull model

7. cylinder
block
Plate

8. cylinder
block
Plate

10. Histogram of average daily temperatures
5 years of California Data
*data from different study
1500 90th’ile = 31°C
1000
500
0 10 20 30 40
°C

11. Histogram of daily temperature range
5 years of California Data
6000
*data from different study
5000 90th’ile = 20.6°C
4000
3000
2000
1000
5 10 15 20 25 30
°C

12. Sample size & test design Sample size & test design
for thermal cycling– using for temperature – using
Wasserman Success Testing Meeker Hahn monograph

13. Current Draw, TP1,2,3,4,5,6
Thermal Cycling Results
60
55
50
Current Draw (mA)
Current Draw over 2 years thermal cycling
45
60
40
55
35
50
Current Draw (mA)
30
45
1 2 3 4 5 6
Test Points 40
35
30
500 1000 1500 2000
Hours
Intercept no significantly different than zero

14. 98.3% within specification after 2 years
with 95% confidence

15. Current Draw 45°C Samples
Temperature only data
60
Aged at 45°C Current Draw
50
60
40
50
Current
30
40
20
30
TP0 TP1 TP2 TP3 TP4 TP5
20
0 10 20 30 40
Days

16. 99.4% within specification after 2 years
with 95% confidence