Pilz PMCprimo DriveP.01/AA0/4/0/0/208-480VAC - Manual (Page 90)

Technical details
Operating Manual PMCprotego S1­2(­C)
1002528­EN­02 90
The safety­related characteristic data is valid for all safety functions.
All the units used within a safety function must be considered when calculating the safety
characteristic data.
9.1.2 Safe actuator with two encoders
Operating
mode EN ISO
13849­1:
2008
PL
EN ISO
13849­1:
2008
Category
EN IEC
62061
SIL CL
EN IEC
62061
PFH
D
[1/h]
IEC 61511
SIL
IEC 61511
PFD
EN ISO
13849­1:
2008
T
M
[year]
Safe actu­
ator
PL e Cat. 4 SIL CL 3 1,46E­08 SIL 3 4,72E­04 20
The safety analysis of the plant or machine may necessitate a second encoder (external
encoder). Example: Fault detection in the mechanical transmission path between motor and
process.
The sensor subsystem consists of the motor encoder (sensor 1) and an external encoder
(sensor 2). A separate PL or SIL must be calculated for this subsystem. For this subsystem
structure, Category 3 with a DC of 99 % is acceptable. The following characteristic data is
required for both sensors (motor encoder and external encoder): MTTF
d
and λ
d
/λ.
Subsystem
Safe actuator
Subsystem
Sensor
Sensor 1
Motor encoder
Sensor 2
External encoder
Diversity
with cross-
comparison
PMCprotego D
PMCprotego S1
The safety­related characteristic data is valid for all safety functions.
All the units used within a safety function must be considered when calculating the safety
characteristic data.