AT&T System 75 Wiring Diagram page 111

CHAPTER 3. EQUIPMENT ROOM DESIGN
mounting screw 7-11/16 inches to the right of the screw just
installed. Repeat Steps 3, 4, and 5.
If a horizontal patch cord trough is to be installed, install it, on the
8.
line, between the trunk/auxiliary field and the distribution field.
9. To install the first distribution field terminal block, partially install
two 3/4-inch, No. 12 wood screws, 7-11/16 inches apart on the line,
to the right of the vertical patch cord trough. Repeat Steps 3, 4, and
5.
10. If another distribution field terminal block is to be installed, partially
install the first screw for the terminal block, on the line, 7/8 inch to
the right of the previous screw. Partially install the second mounting
screw 7-11/16 inches to right of the screw just installed. Repeat
steps 3, 4, and 5.
11. If a vertical patch cord trough is to be installed in the distribution
field, go to Step 6.
12. Repeat Steps 10 and 11 until all the terminal blocks and vertical
patch cord troughs in the distribution field have been installed.
Frame Mounting 110P-Type Terminal Blocks
The 900-pair 110P-type terminal blocks and the associated patch cord
troughs can also be mounted on a free-standing, floor-mounted 1110A2
apparatus mounting frame (Figure 3-16). Each 1110A2 apparatus
mounting frame provides the space to mount five terminal blocks/patch
cord troughs on each side of the frame. A cable support structure,
apparatus mounting 1110C1, mounts directly on top of the 1110A2
apparatus mounting frame and provides support for all cables routed to
and from the frame.
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