SICK L4000 Instrucciones De Operación página 76

en
Chapter 4
Note
Note
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Installation and mounting
Example:
Access protection with two beams C = 850 mm
Machine stopping/run-down time = 290 ms
Response time from interruption of the light path = 30 ms
Approach speed of personnel = 1.6 m/s
T = 290 ms + 30 ms = 320 ms = 0.32 s
S = 1600 x 0.32 + 850 = 1362 mm
How to calculate the safety distance D
ANSI B11.19:2003-04, Annex D and Code of Federal Regulations,
Volume 29, Part 1910.217 ... (h) (9) (v):
The following calculation shows an example calculation of the safety
distance. Depending on the application and the ambient conditions, a
different calculation may be necessary.
= First calculate D using the following formula:
s
D = H x (T + T
s s s c
Where ...
D = The minimum distance in inches (or millimetres) from the
s
hazardous point to the protective device
H = A parameter in inches/second or millimetres/second,
s
derived from data on approach speeds of the body or parts
of the body.
Often 63 inches/second is used for H
T = Stopping/run-down time of the machine tool measured at
s
the final control element
T = Response time of the control system
c
T = Response time of the presence-sensing device and its
r
interface
T = Additional response time allowed for brake monitor to
bm
compensate for wear
Any additional response times must be accounted for in this
calculation.
D = An additional distance added to the overall safety distance
pf
required. This value is based on intrusion toward the hazar-
dous point prior to actuation of the electro-sensitive
protective equipment (ESPE). The value for applications
where reaching over is possible is D
arrangements that allow reaching in with the arm, or the
detectable object size is greater than 63 mm, D
according to
s
+ T + T ) + D
r bm pf
Operating Instructions
L4000 system
.
s
= 1.2 m and for beam
pf
= 0.9 m.
pf
8010009/YTA2/2016-05-02
Subject to change without notice