Panasonic is part of a large worldwide groupselling relays and associated switching products under different brand names in different territories.The conditions of use in some territories may differ from those customary in Europe. In particular there are often major differences in regard to national and international specifications, such as UL, CSA, VDE, SEV, EVE, SEMKO, etc. Thus, when considering contact loads as stated in this catalogue (e.g. 10 A, 30 VDC for the SP relay) its hould be understood that these values are not necessarily an absolute maximum but tested ratings. Mostly the stated value has been tested for a certain life expectancy as stated by the manufacturer or the respective test house. Thus, under different conditions, the stated “maximum” may, in practice, be safely exceeded.
2. Failure Rate
F ilu ilu te
a ilu rate.
T tiv f
M TTF .
3. Maintainability
MTTR
Preventive maintenance, predicted
maintenance
3. Reliability (narrow sense), durability
Long life time: MTTF, B10, R(T),
Low failure rate: Lamda (X), MTBF
2. Reliability Narrow Sense the
Term
In tria rld lia ility an
in rtic t
s ith ilu .
T fin e
d lia ility llo :
T ility ,
e ifie d
fu tio tio n
u ifie itio .
1.
Availability
3. F
o lie ira . Degree Reliability
D lia ility ts
p tio lia ility.
S tim t
th life tim ilu .
M lls be
u ith repair.
F ira ir
s ility ility r
p itio lia ility t
d rio r
th rin stry.
64
.
P t/c lly ys.
M ilu fin llo :
M ilu tal ilu t/
to tin rs
In ilu to
m ilu te. lia ility
o itse lf, ility e
p lia ility . Design reliability
Human factor, redundancy,
fool-proof, fail-safe
[2] RELIABILITY MEASURES
T llo list e
m lia ility :
Reliability measure
Sam ple
representation
Degree reliability R(T) 99.
F ilu fte e
u t/h rts ith w
fa ilu “fa ilu it) 10-9 /
h fte ilu te. MTBF
M tim e
b ilu n
tim rio ,
e lly
b pair.
P lia ility r's ite is
c lle lia ility ts
m lia ility In
th stry, lia ility a
s ific .
2.
T tin e
n fin ite t
h it
Reliability
(broad sense)
a it.Excerpts from Technical Information
RELIABILITY
[1] WHAT RELIABILITY?
1. lia ility f
re ira as
“ lia ility . ts
th ility ,
e rt, tin d
n tio rta f
tim lty t
s ifie tim rio .e. MTTF
M tim to
fa ilu tim rio d
u til lty F
n lly lie ira ts
s rts ria . rt,
re lia ility i. Reliability Broad Sense the
Term
E fin ite life tim . Intrinsic Reliability and Reliability
of Use
R lia ility ilt” is
re rre trin lia ility h
c lia ility rro w
s . r
e lig s
fa ile f
re lia ility fin in, tim is
1 s
re live lia ility is
3 .9%
M TBF 100 hours
M TTF 100 hours
Failure rate fit, /hour
Safe life B10 hours
(b) MTTF
(c) Safe life
1.
4
