2.3.5.2
Lever Arm Type Limit Switches
Provide for anchored group doors to stop the travel of each group in the
fully open and fully closed positions. The limit switches shall be:
a.
Positive acting, snap action, lever arm type with actuating cams
designed with sufficient overtravel to permit the group to come to
a complete stop without overtraveling the limit switches.
b.
Mounted on the leaves, and the actuating cams mounted either on
the top guides or on adjacent door leaves.
2.3.6
Safety Edges
**************************************************************************
NOTE: Edit to suit type of door operation required.
**************************************************************************
Provide fail-safe safety edges on [each edge of each leaf of individually
operated doors] [each leading and trailing edge of drive leaves for
floating group doors] [the leading edge of the drive leaf of anchored group
doors] from 25 mm one inch above the floor to the top of the door leaf.
For leaves 300 mm 12 inches thick (including siding) or less, provide a
single run of safety edge the full width of door. For leaves over 300 mm
12 inches thick (including siding,) provide a double run of safety edge
spaced to provide the maximum degree of safety in stopping the leaves. For
leaves over 300 mm 12 inches thick (including siding) provide a double run
of safety edges on the outer edge of each side of door leaf covering no
less than 80% of leaf.
a.
Design: Provide safety edges to provide a minimum of 90 mm 3 1/2
inches of overtravel after actuation until solid resistance is met
and door motion comes to a complete stop. If door requires more
than 90 mm 3 inches to come to a complete stop, provide
additional overtravel built into safety edge the distance required
for door motion to come to a complete stop. Use electric safety
edges.
b.
Specs: Use sensing edges of reinforced polyvinyl chloride cover
or other Government-approved material with chemical resistance to
diesel and JP-4 fuel, hydraulic fluids, SAE-30 oil and salt water.
Use cover that provides hermetic seal for weather and moisture
resistant protection of internal foam and contact elements.
Internal foam may be polyurethane and/or latex foam per military
specification MIL-R-5001, medium density. Use two contact
elements separated by perforated foam or other Government
-approved materials and design to perform the switching function
when the sensing edge encounters an obstruction along any portion
of its active length.
b.
Operation: Actuation of the safety edge on leading edge of a
group of leaves shall stop movement of the group. Actuation of a
safety edge shall lock out the motor control in the direction of
travel until reset, but shall permit the door to be reversed away
from the obstruction which tripped the safety edge. Safety edges
shall be alive only when doors are moving. Safety edges shall be
reset by moving doors away from the obstruction. The lower
portion of the safety edges to a height of approximately 1500 mm 5
feet shall be independently removable for convenience in servicing
SECTION 08342
Page 18
Previous Page
