Chapter
5
Operating Instructions
C4000 Select
32
© SICK AG • Industrial Safety Systems • Germany • All rights reserved
8012247/RI61/2007-11-30
Installation and mounting
Example
Stopping/run-down time of the machine = 290 ms
Response time after light path interruption = 30 ms
Resolution of the light curtain = 30 mm
T
total
= 290 ms + 30 ms = 320 ms = 0.32 s
D
s
= (H
s
× T
total
) + D
pf
= (63 in/s × 0.32 s) + 3.08 in
= 23.25 in (591 mm)
5.1.4
Minimum safety distance according to EN 999 and EN 294
The following table summarizes typical calculations of the minimum safety distance.
Approach
Minimum safety distance calculation based on 30 mm object
detection (resolution) (mm)
Perpendicular
P
= 90º (± 5º)
D
s
= 2000 × T + 128
If D
s
> 500 mm, using the formula above, then recalculate using:
D
s
= 1600 × T + 128
The result of this second calculation cannot be less than 500 mm
Horizontal
P
= 0º (± 5º)
D
s
= 1600 × T + (1200 – 0.4 × H)
Where H is the mounting height and (1200 – 0.4 × H) must be
greater than 850 mm
Angular
5º
P
85º
For
P
30º, use the perpendicular approach.
For
P
30º, use the horizontal approach.
D
s
applies to the furthest beam whose height is 1000 mm
This table presents summary information only and additional requirements may apply for
your application. Consult the relevant standards and regulations for additional require-
ments related to the minimum safety distance calculation.
The following calculation shows an example calculation of the safety distance for a perpen-
dicular (e.g. vertical) installation of a safety light curtain based on EN 999 and EN 294.
First, calculate D
s
using the following formula:
D
s
= 2000 × T + 8 × (d – 14) [mm]
Where …
D
s
= Safety distance [mm]
T
= Stopping/run-down time of the machine
+ response time of the protective device after light path interruption [s]
d
= Resolution of the light curtain [mm] i.e. 30 mm
The reach/approach speed is already included in the formula
If the result D
s
is 500 mm, then use the determined value as the safety distance
If the result D
s
is > 500 mm, then recalculate D
s
as follows:
D
s
= 1600 × T + 8 × (d – 14) [mm]
If the new value D
s
is > 500 mm, then use the newly determined value as the minimum
safety distance
If the new value D
s
is 500 mm, then use 500 mm as the safety distance
3)
D
S
is referenced as “S” in EN 999 and EN 294.
Tab. 16: Minimum safety
distance formula summary
per EN 999 and EN 294
when no floating blanking is
implemented
