Banner EZ-SCREEN SLS, Инструкция по эксплуатации

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May 22, 2023
EZ-SCREEN SLS Safety Light Curtain Instruction Manual
76
The pair in position #1 (connected directly to the machine control), maintains its 15 ms response time. Response time for the
second pair in the cascade circuit increases by 2 ms, to 17 ms; for the third pair by 4 ms, to 19 ms, and for the fourth pair by
6 ms, to 21 ms.
The formula used for U.S. applications (other standards may apply) to calculate separation distance for individual placement
of each emitter/receiver pair in the cascaded system is:
Position #1: Ds = K (Ts + Tr) + Dpf
Position #2: Ds = K (Ts + Tr + 2 ms) + Dpf
Position #3: Ds = K (Ts + Tr + 4 ms) + Dpf
Position #4: Ds = K (Ts + Tr + 6 ms) + Dpf
Use the above formulas in place of the Ds formula in "Calculating the Safety Distance (Minimum Distance)" on page 22 to de-
termine individual separation distance (Ds). This ensures each sensor pair is located at an adequate distance from the haz-
ard.
The cascaded system’s Overall Response Time (Tr) is equal to the response time of the individual sensor pair with the most
beams (the slowest individual response time), plus an adder resulting from the number of systems in the cascade. Tr can be
found by the following formula:
Tr = Tr
(max)
+ [(N-1) × 2 ms]
where:
Tr
(max)
is the response time of the slowest individual pair in the cascade (the pair with the most beams; see "Components"
on page 17 ).
N is the number of sensor pairs in the cascade.
Use Tr value from the formula in "Calculating the Safety Distance (Minimum Distance)" on page 22 to determine Overall
Safety Distance (Ds). This will ensure that all sensor pairs will be located at an adequate distance from the hazard, no matter
how the system is installed.
When contacts, for example, an E-stop button, are connected to a cascaded receiver, the CSSI response time is 40 ms plus
the 2 ms adder for each additional light screen, similar to the defined area Tr.
Tr
(CSSI)
= 40 ms + [(N-1) × 2 ms]
When light screens of different lengths or different resolutions (and therefore different response times) are used in one circuit,
their positions in the cascade may become a consideration.
For example, consider the light screen circuits shown. Each example contains three safety light screens, one 1200 mm (with
a response time of 40 ms), and two 300 mm light screens (15 ms response each). Depending on their placement in the cas-
cade, the individual response time for the same three light screens can vary from 40 to 44 ms.
Overall Response Time and Safety (Minimum) Distance
8.5.2
Cascade Configuration vs. Response Time
8.5.3
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