有谁能告诉我一下,风扇MTBF寿命标蓝色的7是怎么来的?????

zhuangyuwu

L10Expectancy:
80,000hoursminimum@fanratedvoltageandthetemperatureof40℃
AccordingtotheequationforWeibulldistribution,MTTF≒7×L10=
560,000hours
AndwerelyonazerofailureWeibullteststrategyandacceleratedtestingtechnique,todeterminethetotaltesttime(t)forverifyingtheabovelifeestimationbytheequations,
t=1.036×MTTF×[(Br;c)÷n]0.91÷AF,andAF=2(Ts-Tu)/10

where,(Br;c)isPoissondistributionfactorwiththefailurenumberofrequalto0and
thedecimalconfidencelevelofcequalto0.90(90%).