LANTNAVFACENGCOM A&E GUIDE
Circuit breakers, panelboards, etc., shall be rated, calibrated, and labeled by
the manufacturer, and indicated on the contract drawings as 400 Hz
equipment. However, the manufacturer, at his option, may use 60 Hz
equipment if the 60 Hz equipment is properly derated for 400 Hz operation
and if the 60 Hz equipment contains the manufacturer's label stating that the
equipment has been properly derated and is satisfactory for 400 Hz
DIRECT CURRENT (DC) SYSTEMS
Provide in accordance with MIL-STD-704, "Aircraft Electric Power
MIL-HDBK-1004/4. "Electrical Utilization Systems," Section 4.
GENERAL DESIGN PROCEDURE
See Telecommunications Coordination and Responsibility Chart (Figure 9).
a. Provide sufficient access to and working space around the telephone
backboard. This space shall extend out from the backboard mounted
equipment a minimum of 36 inches and from the floor to a height of
75 inches or to the top of the backboard, whichever is greater. Every
effort should also be made to provide a clear wall space (for entrance
and exit of telephone system conduits) of 12 inches on each side of the
backboard. In addition, provide an exclusively dedicated space
extending from the floor to a height of 25 feet or to the structural
ceiling with a width and depth equal to that of the backboard and
contained equipment. No piping, ducts. or equipment foreign to the
telephone equipment or architectural appurtenances shall be permitted
to be installed in. enter. or pass through such spaces.
b. Indicate the size, the mounting orientation, and the mounting height of
the telephone backboard.