Calculating The Safety Distance - Honeywell SmartPAC 2 User Manual

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Calculating the Safety Distance

DANGER
!
INCORRECT SAFETY DISTANCE
• Calculate the safety distance carefully according to the instructions below, and mount your
light curtain heads at least this distance from the hazardous area.
• Mount your light curtain heads at least 7.5" (191 mm) from the hazardous area, regardless of
the calculated safety distance.
Failure to comply with these instructions will result in death or serious injury.
Before you can calculate the correct safety distance, you must know your press's stopping
time. You can find the press's stopping time using SmartPAC 2. You must use the 90° stop
time test to find stopping time. This is required by OSHA regulation 1910.217. During this
test, the press control stops the press at 90° of the stroke and displays stop time. How to
perform this test is covered in the previous section.
After you know the press's stopping time, you can calculate the safety distance. Shadows
must be mounted away from the pinch point (or hazardous area) of the machinery at a
specific distance. This distance is based on stopping time. The safety distance must be
calculated using a precise formula. This ensures that Shadow can send the stop signal to the
press, and the press will stop, before the operator's hand reaches the hazardous area. (The
safety distance is also discussed in the Shadow light curtain user manual.)
Figure 6 - 19. Distance Between Pinch Point and Light Curtain on a Press
ANSI and OSHA Safety Distance Formulas
You are governed by Occupational Safety and Health Administration (OSHA) regulations
when mounting Shadows. The Shadow, must be located at the correct safety distance from
the pinch point. OSHA regulation 1910.217 specifies requirements for light curtains when
used with mechanical power presses.
When calculating safety distance, however, Honeywell recommends you use the formula
from the American National Standards Institute (ANSI)—standard B11.1-1988. The formula
represents a new consensus among manufacturers on the proper installation of light curtains.
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One of Shadow's
invisible light beams
Shadow transmitter
Chapter 6
SmartPAC 2 with WPC Integration
pinch point
Distance between
light curtain and Shadow
pinch point receiver
SmartPAC 2 Run Mode