电容寿命计算方式

ACT-RX Technology Corporation MTTF&L10 Life Test ReportModel No. TM31 Current Bearing System Test Sample (pcs) Test Hours/Each Over Total Test Hours Failure Criteria 50 3000 150000 Test Condition Input Voltage 12VDC Test Temp. Direction Start Date 70℃ Vertical 2/13'04 Number of Failure Confidence Level Get MTTF at 70℃ Get L10 at 70℃ 65143 6863 0 90﹪ Electrical Specification Speed 5800RPM 0.11Amp

CeraDyna A

Finish Date 6/21'04 Total Test Hours =50*3000 = 150000Hours The Estimated MTTF =150000/2.3026=65143 Hours(IEC-60605-4:2001 section Failure mode

Test Result: (TTF: Time To Failure; UUT: Unit Under Test; F/R: Failure Rate, Datum, Sta

1. Speed: Under 15% of original value Accu. F/O TTF(Hours) UUT(pcs) Accu. F/R 2. Current: Over 15% of original value 3. Fan not run Remark: other competitors failure criteria - 30% Check point at the hours of 0, 250, 500, 750,1000,1500,2000… MTTF Test Result AF:Acceleration factor for calculating MTTF at different temperature. AF=2^﹝(Ta – Tu) / 10﹞ Ta:Test temperature , Tu:Reference temperature The following produre explains the derivation of L10

Point estimates, confidence intervals, prediction intervals and tolerance intervals mL1: Lower one-sided limit for the mean time to failure (MTTF) mL1 =

2T* χ21-α

1-α: Confidence Level (90%) r: Number of Failure

T*:The accumulated test time

The (L10)L1 at a lower one-sided 90﹪ confidence on MTTF is (L10)L1 = 【-ln(0.9)】*mL1 Temp(℃). L10 30℃ 109815 40℃ 54908 50℃ 27454 60℃ 13727 70℃ 6863

2T*

(2r+2): Degree of Freedom X21-α(2r+2):Tables of the fractiles of the χ2 distribution

Calculation Refer To: IEC 60605-4:2001, EQUIPMENT RELIABILITY TESTING – Part 4:Statistical procedures fo exponential distribution – Point estimates, confidence intervals, prediction intervals and tolerance intervals. Approved : Neil Chang Checked : Robert Tested : Helen Tsai

ACT-RX Technology Corporation

0 90﹪ Hours Hours

3 Hours(IEC-60605-4:2001 section 5.1) Failure mode

Test; F/R: Failure Rate, Datum, Stastics…etc.)

(0.9)】*mL1

Part 4:Statistical procedures for

Helen Tsai

（0.9

）】*mPart 4：ai