Omron F3SG-SRB Series User Manual page 281

Calculation Example for Systems with Larger Detection Capability than 40mm
Use K = 1,600 mm/s and C = 850 mm in formula (1) for calculation.
S = 1,600 mm/s x (Tm + Ts) + 850 . . . Formula (4)
• S = Safety distance (mm)
• Tm = Machine's response time (s)
• Ts = Response time of the F3SG-SR from ON to OFF (s)
[Calculation example]
When Tm = 0.05 s and Ts = 0.008 s:
S = 1,600mm/s x (0.05 s + 0.008 s) + 850 mm
= 942.8 mm
 Possible Circumventing by Reaching Over the Detection Zone
If access to the hazardous zone by reaching over the detection zone of vertically mounted F3SG-SR
cannot be excluded, the height and the safety distance, S, of the F3SG-SR shall be determined. S
shall be determined by comparison of the calculated values in  Detection Zone Orthogonal to
Direction of Approach. The greater value resulting from this comparison shall be applied.
S=(K × T) + Cro . . . Formula (5)
• S: Safety distance
• K: Approach speed to the detection zone
• T: Total response time of the machine and the F3SG-SR
• Cro: Approach distance based on the distance which
personnel can move towards the hazardous zone of a
machine by reaching over the detection zone. The distance
is determined in the table below based on the height of the
hazardous zone, a, and the height of the upper edge of the
detection zone, b.
Note: Lower edge of the detection zone above 300 mm in
relation to the reference plane does not offer sufficient
protection against crawling below.
First, use K = 2,000 mm/s in formula (5) for the calculation. If the result of this calculation is less than
100 mm, use S = 100 mm.
If the result exceeds 500 mm, use K = 1,600 mm/s to recalculate it. If the result of the recalculation is
less than 500 mm, use S = 500 mm.
Wiring and Installation
Safety
distance (S)
Hazard
b
a
300 mm max.
Reference plane
E
F3SG-SR
253
User's Manual