Pilz PSEN sc B 5 Series - Overall Response Time Calculation

Project configuration
Operating Manual PSEN sc B 5 Series
1004508-EN-02
19
The minimum distance from the start of the protected area by the safety laser scanner to
the hazardous machine component should be such that the operator cannot reach the haz-
ardous area until the movement of the hazardous machine part has stopped.
In accordance with the standard
} ENISO13855
this distance depends on the following factors:
} Overall response time of the safety laser scanner
Time between the interruption of the laser beam and the OSSDs' change to the OFF
state (see
Calculating the overall response time [ 21]).
} Machine's stopping time
Interval between the change of the OSSD to the OFF state and the stopping of the haz-
ardous machine movement (including the reaction time of the connected relay)
} Approach speed
The speed with which the object to be detected is nearing the hazardous area in mm/s
The following applies for PSEN sc B 5 Series:
S = K * (t
1
+ t
2
) + Z
T
+ Z
R
+ C
S Minimum distance in mm, measured from the start of the safety zone to the danger
source
K Approach speed with which the object to be detected is nearing the hazardous area
in mm/s (in accordance with ENISO13855)
K = 1600 mm/s for S > 500 mm
t
1
Overall response time of the safety laser scanner in seconds
Time it between the violation of a safety zone and signal change at the OSSD output
on the safety laser scanner
t
2
Machine's stopping time in seconds
The time required for the machine to stop after the signal at the OSSD output
changes
C Additional distance depending on the height of the scanning plane and the detection
capability
Z
T
General safety allowance = 150mm
Z
R
Allowance when installing near intense light sources or reflective surfaces (see Dis-
tance to intense light sources and to reflective surfaces [ 24])
Determining the additional distance C depending on the height of the scanning plane
and the detection capability (see ENISO13855)
C = (1200 -0.4H)
Please note:
} Permitted height H of the scanning plane
– H = 15(d-50)
d = resolution (see
Technical details [ 66])
– Max. 1000 mm