Safety Distance; Safety Distance Formulas According To Iso 13855/En Iso 13855 - Omron F3SG series User Manual

Wiring/Installation

4-1-2. Safety Distance

The safety distance is the distance that must be set between the F3SG-R and a machine's hazardous
part to stop the hazardous part before a person or object reaches it. The safety distance varies
according to the standards of each country and the individual specifications of each machine. Always
refer to the relevant standards.
Make sure to secure the safety distance (S) between the F3SG-R and the hazardous part.
Otherwise, the machine may not stop before a person reaches the hazardous part, result-
ing in serious injury.
The response time of a machine is the time period from when the machine receives a stop signal to when the machine's
hazardous part stops. Measure the response time on the actual system. Also, periodically check that the response time
of the machine has not changed.

4-1-2-1. Safety Distance Formulas according to ISO 13855/EN ISO 13855

Detection Zone Orthogonal to Direction of Approach
S = K x T + C . . . Formula (1)
•S: Safety distance
•K: Approach speed to the detection zone
•T: Total response time of the machine and F3SG-R
•C: Additional distance calculated by the detection capability
(or object resolution) of the F3SG-R
Calculation Example for Systems with a Resolution of 
30 mm
Use K = 2,000 mm/s and C = 8 x (d - 14 mm) in formula (1)
for the calculation.
S = 2,000 mm/s x (Tm + Ts) + 8 x (d - 14 mm)
•S = Safety distance (mm)
•Tm = Machine's response time (s)
•Ts = Response time of the F3SG-R from ON to OFF (s)
•d = Detection capability (or object resolution) of the F3SG-R (mm)
[Calculation example]
When Tm = 0.05 s, Ts = 0.08 s, and d = 14 mm:
S=2,000 mm/s x (0.05 s + 0.08 s) + 8 x (14 mm - 14 mm)
= 116 mm . . . Formula (2)
If the result
If the result exceeds 500 mm, use the following expression where K = 1,600 mm/s.
S=1,600 mm/s x (Tm + Ts) + 8 x (d - 14 mm) . . . Formula (3)
If the result of this formula (3)
Possible Circumventing by Reaching Over the Detection Zone
If access to the hazardous zone by reaching over the detection zone of vertically mounted F3SG-R
cannot be excluded, the height and the safety distance, S, of the F3SG-R shall be determined. S shall
F3SG-R
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User's Manual
<
100 mm, use S = 100 mm.
<
500 mm, use S = 500 mm.
Safety distance (S)
Hazard