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.
T tiv f
M TTF . Failure Rate
F ilu ilu te
a ilu rate.
T tin e
n fin ite t
h it
Reliability
(broad sense)
a it.
64
.
4. Intrinsic Reliability and Reliability
of Use
R lia ility ilt” is
re rre trin lia ility h
c lia ility rro w
s . 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. Reliability Narrow Sense the
Term
In tria rld lia ility an
in rtic t
s ith ilu .e.9%
M TBF 100 hours
M TTF 100 hours
Failure rate fit, /hour
Safe life B10 hours
(b) MTTF
(c) Safe life
1. MTBF
M tim e
b ilu n
tim rio ,
e lly
b pair.
S tim t
th life tim ilu . F
o lie ira . rt,
re lia ility i. MTTF
M tim to
fa ilu tim rio d
u til lty F
n lly lie ira ts
s rts ria . r
e lig s
fa ile f
re lia ility fin in, tim is
1 s
re live lia ility is
3 . Maintainability
MTTR
Preventive maintenance, predicted
maintenance
3.
M ilu fin llo :
M ilu tal ilu t/
to tin rs
In ilu to
m ilu te.
P lia ility r's ite is
c lle lia ility ts
m lia ility In
th stry, lia ility a
s ific . lia ility
o itse lf, ility e
p lia ility .
T fin e
d lia ility llo :
T ility ,
e ifie d
fu tio tio n
u ifie itio . lia ility f
re ira as
“ lia ility . Degree Reliability
D lia ility ts
p tio lia ility.
1.
F ira ir
s ility ility r
p itio lia ility t
d rio r
th rin stry.
P t/c lly ys.Excerpts from Technical Information
RELIABILITY
[1] WHAT RELIABILITY?
1.
F ilu fte e
u t/h rts ith w
fa ilu “fa ilu it) 10-9 /
h fte ilu te.
2. Reliability Broad Sense the
Term
E fin ite life tim .
2.
M lls be
u ith repair.
3. Reliability (narrow sense), durability
Long life time: MTTF, B10, R(T),
Low failure rate: Lamda (X), MTBF
2.
Availability
3. ts
th ility ,
e rt, tin d
n tio rta f
tim lty t
s ifie tim rio
