Rockwell Automation 442L SC300 Safety Sensor User Manual User Manual
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Rockwell Automation Publication 10000202762 Ver 00 - January 2012
Chapter 4
Mounting
K =
2000 mm/s
Definition and value as per prEN ISO 13 855, derived from data on the approach
speed of the body or parts of the body
T =
Stopping/run-down time of the entire system in [s]
Stopping/run-down time of the entire system = Stopping/run-down time of the
machine + response time of the protective device after light path interruption
d =
Detection capability (resolution) of the protective device in [mm]
The reach/approach speed is already included in the calculation formula.
With K = 2000 mm/s the 1st formula is:
1. calculation formula: S = 2000 × T + 8 × (d – 14)
If the result S is
≥ 100 mm and S ≤ 500 mm, then use the determined value as the safety
distance.
Note
As per prEN ISO 13 855 a safety distance S < 100 mm is not allowed. If you obtain a
value S < 100 mm with your calculation, please contact Rockwell Automation.
If the result is S > 500 mm, use K = 1600 mm/s in the formula and calculate S again:
2. calculation formula: S = 1600 × T + 8 × (d – 14)
If the new value S is > 500 mm, then use the newly determined value as the minimum
safety distance.
If the new value S is
≤ 500 mm, then use 500 mm as the minimum safety distance.
Example:
The following values apply:
Stopping/run-down time of the machine = 290 ms
Response time of the SC300 after light path interruption = 20 ms
Detection capability (resolution) d of the SC300 = 20 mm
Note
You will find the values for the response time and the resolution of the SC300 in
“Technical specifications” on page 47.
Minimum safety distance calculation:
•
Step 1: Calculation of the stopping/run-down time of the entire system:
T = 290 ms + 20 ms = 310 ms = 0.31 s
•
Step 2: Insert the values in the 1st formula (S = 2000 × T + 8 × (d – 14)):
S = 2000 Ч 0.31 + 8 Ч (20 – 14) = 668 mm
•
Step 3: Check the value for S.
S > 500 mm. For this reason the 2nd formula must be used.
•
Step 4: Insert the values in the 2nd formula (S = 1600 × T + 8 × (d – 14)):
S = 600 Ч 0.31 + 8 Ч (20 – 14) = 544 mm
•
Step 5: Check the value of S.
S > 500 mm. For this reason 544 mm must be used as the minimum safety distance.