Mtbf, Mttr, Table 6 – Vaisala WAA151 User Manual
Page 28: Mtbf values

User's Guide ________________________________________________________
26 _____________________________________________________ M210293en-A
Property
Description/Value
Recommended
connector at cable end
SOURIAU MS3116F10-6P
Operating temperature
-50 ... +55
°C (with shaft heating)
Storage temperature
-60 ... +70
°C
Housing material
AlMgSi, gray anodized
Cup material
PA, reinforced with carbon fiber
Dimensions
240 (h) Ч 90 (Ш) mm
Swept radius of cup wheel: 91 mm
Weight
570 g
1) Measured with cup wheel in position least favored by flow direction.
Optimum position yields < 0.35 m/s starting threshold.
2) Standard Deviation
MTBF
According to the standard MIL-HDBK-217F calculated
mean times between failures are listed in Table 6 below.
Actually, the last column provides the failure frequency
during 10
6
hours of use.
Table 6
MTBF Values
Abbreviation
Installation
f/10
6
h
Gf
Permanent installations
2.34
Gm
Mobile installations
8.52
Nu
Ship equipments
5.48
MTTR
Mean time to repair is 0.3 h.