SICK microScan3 Core I/O

Calculating minimum distance
T
he calculation of the minimum distance is based on international or national stan‐
dards and statutory requirements applicable at the place of installation of the machine.
If the minimum distance is calculated according to ISO 13855, then it depends on the
following points:
•
Machine stopping time (time interval between triggering the sensor function and
the end of the machine’s dangerous state)
•
Response time of the protective device, see "Response times", page 147
•
Reach or approach speed of the person
•
Resolution (detection capability) of the safety laser scanner
•
Type of approach: orthogonal
•
Parameters specified based on the application
NOTE
A
dditional information is available in the ISO 13855 standard and in the Guidelines
Safe Machinery.
NOTE
SIC
K offers a stopping/run-down time measurement service in many countries.
Calculation example of the minimum distance S according to ISO 13855
T
he example shows the calculation of the minimum distance for an orthogonal
approach to the protective field. A different calculation may be required depending on
the application and the ambient conditions (for example, for a protective field parallel to
or at any angle to the direction of approach or an indirect approach).
b
First, calculate S using the following formula:
S = 2000 mm/s × T + 8 × (d – 14 mm)
where:
°
S = minimum dis
tance in millimeters (mm)
°
T=stopping/run-down time for the entire system in seconds (s)
(Response time of the safety laser scanner + machine’s stopping/run-down
t
ime, incl. response time of the machine’s control system and signal propaga‐
tion time)
°
d = r
esolution of the safety laser scanner in millimeters (mm)
The reach/approach speed is already included in the formula.
✓
If the result S is ≤ 100 mm, use S = 100 mm.
✓
If the result 100 mm < S ≤ 500 mm, use the calculated value as the minimum
distance.
b
If the result is S > 500 mm, you may be able to reduce the minimum distance
using the following calculation:
S = 1600 mm/s × T + 8 ×(d – 14 mm)
✓
If the new value is S > 500 mm, use the newly calculated value as the minimum
distance.
✓
If the new value S is ≤ 500 mm, then use 500 mm as the minimum distance.
5.3.8 Access protection
Overview
T
he safety laser scanner is mounted with a vertical scan plane in a stationary applica‐
tion, for example on a machine, for which access to the hazardous area may be defined
structurally. For access protection, the safety laser scanner detects an intrusion by a
whole body. The protective field is orthogonal to the person’s direction of approach.
PROJECT PLANNING 5
8025870/2020-09-04 | SICK O P E R A T I N G I N S T R U C T I O N S | microScan3 Core I/O
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Subject to change without notice