Schneider Electric ALTIVAR 58 TRX - Manual (Page 225)

Class 8998 Motor Control Centers
Sample Specifications
225
09/2003 © 2000–2003 Schneider Electric All Rights Reserved
shall be connected directly to the main horizontal bus with appropriately size cable or riser bus.
f. All AC drive controller units shall be enclosed in a structure which contains a 12" (305 mm) high
horizontal wireway at the top of each section, and a 6" (152 mm) high horizontal wireway at the
bottom of each section. These wireways should be unobstructed the full length of the motor control
center to allow room for power and control cable to connect between units in different sections.
g. A full-depth vertical wireway shall be provided within motor control center sections containing AC
drive controller units up to 50 hp variable torque. The vertical wireway shall connect both the top and
bottom horizontal wireways, and shall be isolated from the AC drive controller unit interiors by a full
height barrier. The vertical wireway shall be at least 4" (102 mm) wide with a separate hinged door.
There should be a minimum of 4,000 cubic inches (65,548 cubic millimeters) of cabling space
available. Access to the wireways shall not require opening control unit doors. AC drive controller
units that require a full section are not required to have vertical wireways.
h. All AC drive controller unit interior mounting panels shall be white for better visibility inside.
i. The motor control center structure shall include unit mounting shelves with hanger brackets to
support AC drive controller units up to 50 hp variable torque during installation and removal. A twin
handle camming lever shall be located at the top of AC drive controller units up to 50 hp variable
torque to rack the unit in and out.
j. A cast metal handle operator shall be provided on each AC drive controller unit disconnect. With the
AC drive controller unit connected to the motor control center bus and the AC drive controller unit
door closed, the handle mechanism shall allow complete on/off control of the unit disconnect, with
clear indication of the disconnect’s status. All circuit breaker operators shall include a separate
tripped position to clearly indicate a circuit breaker trip condition. It shall be possible to reset a tripped
circuit breaker without opening the control unit door.
1. A mechanical interlock shall prevent an operator from opening the AC drive controller unit door
when the disconnect is in the on position. Another mechanical interlock shall prevent an operator
from placing the disconnect in the on position while the AC drive controller unit door is open. It
shall be possible for authorized personnel to defeat these interlocks.
2. A non-defeatable interlock shall be provided between the handle operator and the structure to
prevent installing or removing a plug-on AC drive controller unit unless the disconnect is in the
off position.
k. Provisions shall be provided for locking all disconnects in the off position with up to three padlocks.
l. All plug-on AC drive controller units shall have a grounded stab-on connector which engages the
vertical ground bus prior to, and releases after, the power bus stab-on connectors.
m. Handle mechanisms shall be located on the left side to encourage operators to stand to the left of
the unit being switched.
n. Unit construction shall combine with the vertical wireway isolation barrier to provide a fully
compartmentalized design.
o. All AC drive controller units shall be provided with unit control terminal blocks for use in terminating
field wiring. Terminal blocks shall be pull-apart type, 250 Vac, and rated for 10 A. All current-carrying
parts shall be tin-plated. Terminals shall be accessible from inside the unit when the unit door is
opened. The stationary portion of the terminal block shall be used for factory connections and will
remain attached to the unit when the portion used for field connection is removed. The terminals
used for field connections shall be accessible so they can be wired without removing the unit or any
of its components.
2.04 Thermal Management
a. The AC drive controller unit shall incorporate a self-contained air-based cooling system. Any air
exhaust vents shall be louvered to help direct air flow away from personnel operating the AC drive
controller unit. Any fans, ductwork, or filters shall be easily accessible for maintenance.
b. The AC drive controller unit cooling system shall be sized to cool the drive regardless of mounting
location within the motor control center. The AC drive controller unit shall not be restricted to a
specific location in the motor control center.