Siemens TIASTAR SFIM-70020, Руководство пользователя

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F2
Siemens Energy & Automation, Inc. 1000 McKee Street Batavia, Illinois 60510
SFIM-7002A-0501
Section F, September, 2001
2.4 MCC's shall be assembled in such a manner that it is
not necessary to have rear accessibility to remove any
internal devices or components.
Bus
3.0 The main horizontal bus shall be rated at (600) (800)
(1200) (1600) (2000) amperes. Horizontal bus bars shall
be mounted edge wise and located at the top of the
MCC.
3.0.1 All power bus shall be braced to withstand a fault
current of (42,000) (65,000) (100,000) RMS sym-
metrical amperes.
3.1 Horizontal bus shall be tin (silver) plated copper with a
conductivity rating of 100% AICS. The horizontal bus
bars shall be fully sized to carry 100% of the rated cur-
rent the entire length of the MCC. Tapered horizontal
bus is not acceptable.
3.1.1 Regardless of amperage rating, the entire horizon-
tal bus assembly must be located behind the top
horizontal wireway. Horizontal bus bars located
behind usable unit space are not acceptable.
3.1.2 The horizontal bus shall be isolated from the top
horizontal wireway by a clear, flexible, polycarbon-
ate (Lexan®) barrier allowing visual inspection of
the horizontal bus without removing any hardware.
3.2 The vertical bus shall be rated 300 (600) amperes.
Vertical bus bars shall be fabricated of tin (silver) plated
solid copper bars with a conductivity rating of 100%
AICS.
3.2.1 The vertical bus assembly shall be isolated from
the unit mounting space by means of a full height
steel barrier. Provisions shall be made to close off
unused unit stab openings in the vertical bus barri-
er with removable covers.
-- OR --
The vertical bus barrier support shall be designed
as to effectively enclose each vertical bus bar.
Provisions shall be made to close off unused unit
stab openings in the vertical bus barrier with
removable covers.
3.3 All bus ratings are to be based on a maximum tempera-
ture rise of 50
I
C over a 40
I
C ambient temperature.
3.4 Horizontal to vertical bus and horizontal bus splice con-
nections shall be made with two (2)
3
/
8
" grade 5 bolts
and Belleville-type conical washers at each connection
point. All connecting hardware shall be designed to be
tightened from the front of the MCC without applying
any tools to the rear of the connection.
Units
4.0 Plug-in units shall connect to the vertical bus by means
of self-aligning, tin plated copper stab-on connectors
provided with spring steel back-up springs to insure pos-
itive connection to the vertical bus.
4.0.1 When vertical ground bus is specified, plug-in units
shall include a ground stab which engages the ver-
tical ground bus before the power stabs engage
the vertical bus when the unit is inserted into the
structure. When the plug-in unit is withdrawn from
the vertical bus, the vertical ground stab shall
release after the power stabs.
4.1 The interior of all MCC units shall be painted white,
including unit top and bottom plates or isolation barriers.
4.1.1 All plug-in units 12" tall and larger will include two
(2) auxiliary handles to aid in installation, removal
and transporting plug-in units.
4.1.2 All plug-in units will include a racking mechanism
to assure full engagement of the stab-on connec-
tors with the vertical bus.
4.1.3 Plug-in units shall be provided with interference
type draw-out to prevent complete removal of the
plug-in unit from the structure in one motion. The
interference mechanism shall also provide clear
indication when the plug-in unit has been with-
drawn to the "TEST" position.
4.1.4 A mechanical interlock shall be supplied on all plug-
in units to prevent insertion of removal of a unit
from the structure when the unit operator handle is
in the ON position. This interlock may not be
defeated.
4.1.5 Each 12" tall and larger plug-in unit shall be secured
in the structure by two (2) readily accessible
devices, one of which is tool operated. These
devices shall be located at the front of the unit.
4.1.6 Plug-in units with NEMA Type B or C wiring shall be
supplied with unit terminal block mounted on the
right hand side of the unit, adjacent to the vertical
wireway. The terminal blocks shall be mounted on
a movable bracket that maintains the terminals
inside the unit structure for normal operation and
pivots into the vertical wireway exposing the ter-
minals for wiring, test and maintenance.
4.1.7 All plug-in units shall include a positive means of
grounding the unit to the structure at all times.