KEYENCE SL-V Series User Manual
Page 82
3-2
Safety Distances
3-6
In
3
SL-V-M-NO3-E
Example 2 :ANSI B11.19-2010
Safety distance calculation according to ANSI B11.19-2010 (in a case where the detection zone is
orthogonal to the direction of approach)
Equation Ds=K x T + Dpf
Ds : Safety Distance (inch)
K : The maximum speed that an individual can approach the hazard
T : The total time that it takes for the hazardous motion to stop, or for the hazardous portion of the
machine cycle to be completed. This value includes portions of time that vary by machine type
and by the safeguarding device applied.
Dpf : The distance (depth) penetration factor. This value varies depending on the SL-V detection
capability. Dpf=3.4 (S-0.275) inch. See the following figure.
Penetration factor, Dpf, for presence-sensing devices used in a vertical application with object
sensitivity less than 64 mm (2.5 inches)
One of the accepted values for K is the hand speed constant (It is usually considered as the horizontal
motion of the hand and arm while seated). Its common value is 1.6m/s (63inch/s) although other values
(typically greater) are also used. The hand speed constant does not include other body movements,
which can affect the actual approach speed. Consideration of the above factors should be included
when determining the speed constant for a given application. OSHA 1910.217(c) provides K = 63 inch/s
(= 1,600 mm/s) as a recommended value.
For more detail information, especially calculation for the value of “T”, see ANSI B11.19-2010, Annex D.
0.0
25
(1.0)
50
(2.0)
76
(3.0)
102
(4.0)
127
(5.0)
152
(6.0)
178
(7.0)
64 (2.5)
51 (2.0)
38 (1.5)
25 (1.0)
13 (0.5)
0.0
Detection
capability:
S mm (inch)
Dpf = 3.4 (S-7) mm
(Dpf = 3.4 (S-0.275) inch)
Additional distance Dpf mm (inch)