KEYENCE SL-CHG Series - Manual (Page 26)

Chapter 2 Installation and Assembly
2-8
2
English ENGLISH
2-2-4 ANSI B11.19-2003
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-CHG
detection 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)
Minimum
Object
Sensitivity,
S
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 B11.19-2003,
Annex D.
2-2-5 ANSI/RIA R15.06-1999
zone)>
Formula: S = [K x (Ts + Tc + Tr)] + Dpf
S: Safety distance (mm)
K: Approaching speed of the body or the part of body into detection zone (= 63 inch/s)
Ts: Final stop time required when stop control is issued to machine (s)
Tc: Maximum response time of machine's control system (s)
Tr: Maximum response time of the SL-CHG and its interface (s)
Dpf: Additional distance (mm) from the approach factor as illustrated below. This value varies
depending on the SL-CHG detection capability.
Additional distance Dpf (inch)
64mm(2.5)
and greater
51mm(2.0)
38mm(1.5)
25mm(1.0)
13mm(0.5)
0.0 25
(1.0)
51
(2.0)
76
(3.0)
102
(4.0)
127
(5.0)
152
(6.0)
178
(7.0)
203
(8.0)
Minimum
Object
Sensitivity
(Os)
in mm(in)
ANSI/RIA R15.06-1999 Fig. B.2
* ANSI/RIA R15.06-1999 establishes K = 63 inch/s (= 1,600 mm/s) as a minimum speed.
WARNING
Calculate the safety distance accurately and be sure to position the SL-CHG so
that it is separated from the machine's hazardous zone or hazard by at least the
minimum safety distance. Installation of the SL-CHG closer to the hazardous zone
or hazard than the minimum safety distance may result in significant harm to the
machine operator, including death.