MK Diamond Baldor Motor - Manual (Page 13)

Installation & Operation 2-3 MN428
Use a flat washer and lock washer under each nut or bolt head to hold the motor feet secure.
Flanged nuts or bolts may be used as an alternative to washers.
WARNING: Guards must be installed for rotating parts such as couplings, pulleys, external fans, and unused shaft
extensions, should be permanently guarded to prevent accidental contact by personnel.
Accidental contact with body parts or clothing can cause serious or fatal injury.
Guarding Guards must be installed for rotating parts such as couplings, pulleys, external fans, and unused shaft
extensions. This is particularly important where the parts have surface irregularities such as keys, key ways or
set screws. Some satisfactory methods of guarding are:
1. Covering the machine and associated rotating parts with structural or decorative parts of the driven
equipment.
2. Providing covers for the rotating parts. Covers should be sufficiently rigid to maintain adequate guarding
during normal service.
Power Connection
Motor and control wiring, overload protection, disconnects, accessories and grounding should conform to the
National Electrical Code and local codes and practices.
For ExnA hazardous location motors, it is a specific condition of use that all terminations in a conduit box
be fully insulated. Fully insulated and lugged terminations must be bolted and provided with lock washer to
prevent rotation. Flying leads must be insulated with two full wraps of electrical grade insulating tape or heat
shrink tubing.
Grounding In the USA consult the National Electrical Code, Article 430 for information on grounding of motors and
generators, and Article 250 for general information on grounding. In making the ground connection, the
installer should make certain that there is a solid and permanent metallic connection between the ground point,
the motor or generator terminal housing, and the motor or generator frame. In non−USA locations consult the
appropriate national or local code applicable.
Motors with resilient cushion rings usually must be provided with a bonding conductor across the resilient
member. Some motors are supplied with the bonding conductor on the concealed side of the cushion ring to
protect the bond from damage. Motors with bonded cushion rings should usually be grounded at the time of
installation in accordance with the above recommendations for making ground connections. When motors
with bonded cushion rings are used in multimotor installations employing group fusing or group protection,
the bonding of the cushion ring should be checked to determine that it is adequate for the rating of the branch
circuit over current protective device being used.
There are applications where grounding the exterior parts of a motor or generator may result in greater hazard
by increasing the possibility of a person in the area simultaneously contacting ground and some other nearby
live electrical parts of other ungrounded electrical equipment. In portable equipment it is difficult to be sure that
a positive ground connection is maintained as the equipment is moved, and providing a grounding conductor
may lead to a false sense of security.
Select a motor starter and over current protection suitable for this motor and its application. Consult motor
starter application data as well as the National Electric Code and/or other applicable local codes.
For motors installed in compliance with IEC requirements, the following minimum cross sectional area of the
protective conductors should be used:
Cross sectional area of phase
conductors, S
Minimum cross sectional area of the
corresponding protective conductor, S
p
mm 2 mm 2
S< 16 S
16 < S < 35 16
S>35 0,5 S
Equipotential bonding connection shall made using a conductor with a cross-sectional area of at least 4 mm 2 .
Conduit Box For ease of making connections, an oversize conduit box is provided. Most conduit boxes can be rotated
360 º in 90 º increments. Auxiliary conduit boxes are provided on some motors for accessories such as space
heaters, RTD’s etc.