Project Engineering
44
5.1.3.2.2 Safety Clearance for Horizontal Approach to the Safety Field
Danger zone boundary
S
H
S = (K × T ) + C or
S = (1,600 mm/s × T ) + (1,200 mm – 0.4 × H)
S [mm]
Safety clearance
S = (1600 mm/s × T) + (1200 mm – 0.4 × H)
S may not be
≤
850 mm
S is between the danger zone and the furthest beam of the sensor.
K [mm/s]
Approach speed for horizontal approach to the safety field
K = 1600 mm/s
T [s]
Total response time
T = (t
1
+ t
2
+ t
3
)
t1 [s]
Response time of the ESPE
t2 [s]
Response time of the safety switching device
t3 [s]
Machine over-travel time
C [mm]
Margin
C = 1200 mm – 0.4 × H
C
min
≥
850 mm
H
Height of the safety field
200 mm < H < 1000 mm
H
min
Minimum permissible mounting height (never smaller than 0)
H
min
= 15 × (d – 50 mm)
d
Resolution of the ESPE
d = (H / 15) + 50 mm
Required resolution must be calculated for the specified height.
