BBH SMX Series - Page 248

Installation manual
HB-37420-810-01-25F-EN SMX100 Installation manual.docx Page 248 of 260
Version: 25F
Channel B – shut-down via STO/inverter:
Component
MTTFD [years]
DC
Door closer
B10d = 100000
Nop = 30/AT = 9270/year (309 AT/year)
MTTFD =
B10d
0,1 ∗ Nop
=𝟗𝟐𝟕𝟎 𝐲𝐞𝐚𝐫𝐬
DCSwitch = 99%
SIN/COS-
encoder
MTTFD_SinCos = 30 years
DCEncoder = 99%
PES
PFH = 1,4 * 10
-8
MTTFD =
1
8760∗ MTTFD
=107,87 𝑦𝑒𝑎𝑟𝑠  𝟏𝟎𝟖 𝒚𝒆𝒂𝒓𝒔
DCPES = 99%
STO/ inverter
MTTFD_STO = 150 years
DCPES = 90%
MTTFD_A =
1
1
MTTFD_Türz
+
1
MTTFD_SinCos
+
1
MTTFD_PES
+
1
MTTFD_Netzsch
=20,25 years 𝟐𝟎 𝐲𝐞𝐚𝐫𝐬
Resulting PI for both channels:
Symmetry of
both channels:
MTTFD =
2
3
[
MTTFD_A + MTTFD_B −
1
1
MTTFD_A
+
1
MTTFD_B
]
=21,53 years  𝟐𝟏,𝟓 𝐲𝐞𝐚𝐫𝐬
DC mean value
MTTFD
=
DCSwitch
MTTFD_Türz
+
DCSinCos
MTTFD_SinCos
+
DCPES
MTTFD_PES
+
DCSchütz
MTTFD_Schütz
+
DCSTO
MTTFD_STO
1
MTTFD_Türz
+
1
MTTFD_SinCos
+
1
MTTFD_PES
+
1
MTTFD_Netzsch
+
1
MTTFD_STO
=0,9776  𝟗𝟖%
PL
MTTFD = 21,5 years = average
DC avg = 98 % = average
PL =“d“ (from EN ISO 13849-1, tables 5,6, and 7)
In this case the B10d value of the door monitoring feature is is determining for PI.
If an even higher safety level is to be reached a correspondingly higher
qualitative switch is to be used.
Note:
The PI can also be determined with the program tool "Sistema" from BGIA.