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|  MIL-S-17000N(SH)
3.6.20.2.4 Size 20 AWG (green) wire shall be used to terminate the shield
of shielded internal switchboard conductors, that is, between the shield termi-
nating ferrule and the terminal.
3.6.21 Batteries.
Batteries shall only be used as specified in the ATDP.
3.6.22 Signal generator. Where a signal generator is specified in the
ATDP, it shall be in accordance with requirement 17 of MIL-STD-1657.
3.6.23 Supply bus load.
In development of switching requirements for
types II through VI, VIII, IX,
X, and XI switchboards, loads shall be grouped
to limit the maximum connected
load on any one supply bus to 30 A. These
supplies shall be fused at not
more than 35 A on the source switchboard.
3.6.23.1 Bus bars. Bus bars shall be copper in accordance with QQ-C-591.
The edges of bus bars shall have a radius approximately one-half the bar
thickness (full round edges).
3.6.23.2 Use of the bus bars. The use of bus bars shall be kept to a
minimum. The principal use of bus bars shall be for very large currents where
it would be impractical to employ insulated wiring, and as vertical strips
for distribution to individual circuits. In no case shall bus bars be used
as interconnecting circuits between or among switchboard units. Unless speci-
fied in the ATDP, bus bars shall not be attached to hinged structures.
3.6.23.3 Connections between buses. Connections between the buses of
adjacent units of a switchboard shall be made by cables to permit relative
movement of the units under shock without rupturing the switchboard bus circuit.
The cable connections shall be made by the installing activity. The installation
shall conform to the following:
(a) The switchboard design shall provide for the entrance of the
connecting cables into the switchboard structure, and for
connecting to the switchboard bus. The connecting cable shall
extend below the side sheet or flash barrier provided between
adjoining units.
(b) Connecting cable shall be in accordance with MIL-C-915. The
connecting cables shall have a current rating equal to that of
the smaller of two connected buses. Three conductor, heat and
flame resistant, type TSGA of MIL-C-915/30 shall be used with
3-phase buses. Where several cables in parallel are required,
the three phases shall be carried in each cable. For d.c. buses,
one conductor type SSGA of MIL-C-915/28, two conductor type
DSGA, MIL-C-915/29 of four conductor type FSGA, of MIL-C-915/31,
as applicable, shall be used. Paralleling conductors to secure
current carrying capacity is to be avoided wherever practicable.
Armor shall be removed from cable installed within the switch
board enclosures.
Instructions for interconnecting wiring including cable and connector sizes
shall be shown on switchboard drawings (see 3.12).
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