KEYENCE SL-C Series - Manual (Page 29)

Chapter 2 Installation and Assembly
2-7
2
ENGLISH
2-2-2 ANSI B11.19-2010
detection zone is perpendicular 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-C detec-
tion capability. Dpf=3.4(S-0.275)inch. See the below figure.
Penetration factor, Dpf, for presence-sensing devices used in a vertical
application with object sensitivity less than 64 mm (2.5 inches)
64 (2.5)
51 (2.0)
38 (1.5)
25 (1.0)
13 (0.5)
0.0
0.0 25
(1.0)
50
(2.0)
76
(3.0)
102
(4.0)
Dpf = 3.4 (S - 7) mm
(Dpf = 3.4 (S - 0.275) in)
Detection
capability:
S mm (inch)
127
(5.0)
152
(6.0)
178
(7.0)
* 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 con-
stant 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.