Rockwell Automation 1395 DC Drive, 800-1250 Hp, FRN 5.XX-9.30 - Manual (Page 68)

Chapter 4
Installation
4-3
Cooling Airflow In order to maintain proper cooling, the drive must be mounted in a vertical
position (fuses in the upper left hand corner). The recommended minimum
clearance for the drive is 12 inches top, 6 inches sides and 9 inches front
as shown in Figure 4.1.
The drive design produces up to a 10
°
C or 18
°
F air temperature rise when
the drive is operated at full capacity. Precautions should be taken not to
exceed the maximum inlet ambient air temperature of 40
°
C (104
°
F). If the
drive is in an enclosed cabinet, air circulation fans or a closed circuit heat
exchanger may be required.
The heat loss for additional equipment that is mounted in the enclosure
should be added to the heat loss of the drive.
Wiring Clearance Although the minimum clearance should be maintained for proper cooling,
this space may not always provide proper wiring clearance. The minimum
allowable wire bending radius may necessitate that extra space be provided
to accommodate power wiring. Consult the governing code for the proper
wiring method.
Disconnect IMPORTANT: The user is responsible for completing the installation of
the drive system and to comply with all National and Local Electrical
Codes. The following information is to be used as a reference only.
ATTENTION: Hazard of electric shock or equipment damage
exist if drive is not installed correctly. The National Electrical
Code (NEC) and local codes outline provisions for safely instal-
ling electrical equipment. Installation must comply with speci-
fications regarding wire types, conductor sizes, branch circuit
protection and disconnect devices. Failure to do so may result
in personal injury and/or equipment damage.
Wire Size and Type Wire sizes must be selected individually, observing all applicable safety
and NEC regulations. The minimum permissible wire size does not
necessarily result in the best operating economy. Due to the drive overload
capacity, the conductors for the transformer primary and secondary must be
sized (at a minimum) for 125% of the maximum motor current. The motor
armature conductors must also be rated for 125% of the full load motor
current. Motor field conductors should be run with no less than 14 gauge
wire. The distance between the drive and motor may affect the size of the
conductors used.
Shielded type wire is recommended in control circuits for protection
against interference. A shielded wire is required for all signal wires. The
recommended conductor size must be a minimum of 24 AWG. The best
interference suppression is obtained with a wire having an individual shield
for every pair. Table 4.A provides a listing and description of cable types
and wiring recommendations. Figure 4.2 shows recommended cable
shielding.