LEESON Permanent Magnet AC Motors User Manual

Page 8

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Equalize ground potential between the motor and driven equipment
if the driven equipment and motor are not mounted to the same
metallic base plate.


3.4.4.1 Electrical Interference

Due to high switching frequencies of variable frequency drives,
use a low resistance ground cable that is low impedance at high
frequencies. A shielded motor power cable with a complete
circumferential braided or copper film ground jacket around the
power leads is recommended to minimize electrical interference.
Secure this ground to both the motor’s primary ground and the
variable frequency drive ground.

Primary “Internal” Ground: A grounding conductor must be
connected to the grounding terminal provided in the terminal
housing. This grounding terminal is either a ground screw,
ground lug, or a tapped hole to be used with a separately
provided ground screw. The internal grounding feature is
accessible inside the terminal housing and must be used as the
primary grounding connection.

Secondary “External” Ground: Some motors are provided with
a supplemental grounding terminal located on the external
surface of the motor frame or feet. This external terminal is for
supplemental grounding connections where local codes permit or
require such connection.

3.4.5

START UP

WARNING:

LOOSE & ROTATING PARTS HAZARD

Before proceeding read Section 1.2 on Mechanical Safety. Failure
to follow the instructions could result in serious personal injury,
death and/or property damage.

WARNING:

ELECTRICAL LIVE CIRCUIT HAZARD

Shaft rotation produces voltage in PM motors even when motor is
disconnected from power source. Do not open terminal box or
touch unprotected terminals while the motor shaft is rotating.
Failure to do so may cause serious injury or death to personnel.

WARNING:

ELECTRICAL SHOCK HAZARD

Be certain that all connections are secure and the conduit box cover
is fastened in place before electrical power is applied. Failure to
follow these instructions could result in serious personal injury,
death, and/or property damage.

WARNING:

EXCESSIVE SURFACE TEMPERATURE

HAZARDOUS LOCATIONS
Motors with the temperature code stated on the nameplate are
designed to operate within this limit. Improper application or
operation can cause the maximum surface temperature to be
exceeded. A motor operated in a Hazardous Location that exceeds
this surface temperature limit increases the potential of igniting
hazardous materials. Therefore, motor selection, installation,
operation, and maintenance must be carefully considered to ensure
against the following conditions: (1) Motor load exceeds service
factor value, (2) Ambient temperature above nameplate value, (3)
Voltages outside of limits in Section 3.4.1.2, (4) Loss of proper
ventilation, (5) VFD operation exceeding motor nameplate rating,
(6) Altitude above 3300 feet / 1000 meters, (7) Severe duty cycles,
(8) Repeated starts, (9) Motor stall, (10) Motor reversing, and (10)
Single phase operation. Failure to follow these instructions could
result in serious personal injury, death and/or property damage.

CAUTION:

USER CONTACT OF

HOT SURFACE

Normal motor surface temperatures may exceed 90 ° C (194° F).
Touching the motor frame may cause discomfort or injury. Surface
temperatures should only be measured with suitable instruments
and not estimated by hand touch.

3.4.5.1

Start Up - No Load Procedure

WARNING:

ROTATION HAZARD

Incorrect motor rotation direction can cause serious or fatal injury
or equipment damage. Verify rotation direction before coupling to
driven equipment.

1. Check Instructions:

Before startup carefully read and fully

understand these instructions including all warnings, cautions,
and safety notice statements.

2. Motor out of storage after more than three months:

C

heck winding insulation integrity with a Megger. If winding

resistance to ground is less than 1.5 Meg-ohms consult the local
authorized service shop before energizing the motor.

3. Check Installation:

Mechanical - Check tightness of all

bolts and nuts. Manually rotate the motor shaft to ensure motor
shaft rotates freely. Note: Motor will not turn freely if power
leads are shorted together. User may feel small pulsations
when turning shaft due to the magnets in rotor. Shaft & bearing
seals will add drag.
Electrical - Inspect all electrical connections for proper
terminations, clearance, mechanical tightness and electrical
continuity. Be sure to verify connections are made per the
nameplate connection diagram or separate connection plate.
Replace all panels and covers that were removed during
installation before energizing the motor.

4. Energize Motor:

Check Rotation

If practical, check motor rotation before coupling to the load. If
motor has a rotational arrow, only operate the motor in the
rotation identified. Energize VFD and momentarily jog motor to
verify direction of rotation. If opposite rotation is required, (a)
select reverse rotation from VFD or (b) de-energize VFD,
remove power, then reconnect motor leads for reverse rotation.
Repeat jog cycle and ensure proper rotation.

5. Record No Load Amps, Watts & Voltage:

Recommend - To establish a baseline value check and record
the no load amps, watts, and voltage.

3.4.5.2

Start Up – Load Connected Procedure

1. Check Instructions:

Before startup carefully read and fully

understand these instructions including all warnings, cautions, &
safety notice statements.

2. Coupling Installation:

Check that the connected equipment

is properly aligned and not binding. Check that all guards and
protective devices are properly installed.

3. Energize Motor:

When all personnel are clear of the

machine, apply power and verify that the load is not transmitting
excessive vibration back to the motor though the shaft or the
foundation. Verify that motor amps are within nameplate rating.
The equipment can now be fully loaded and operated within
specified limits as stated on the nameplate.


4.0

MAINTENANCE

WARNING:

ELECTRICAL SHOCK HAZARD: Voltage may be

present at the motor terminals even after the motor has stopped rotating.
Disconnect power to the VFD and verify VFD DC output voltage is zero
before performing service or maintenance.

Failure to follow this

instruction could result in serious personal injury or death.

WARNING:

ELECTRICAL SHOCK HAZARD

Electrical connections are to be made by a qualified electrician in
accordance with all applicable codes, ordinances and sound practices.
Failure to follow these instructions could result in serious personal injury,
death and/or property damage. Only qualified personnel who are familiar
with the applicable national codes, local codes and sound practices
should install or repair electric motors and their accessories.

WARNING:

ELECTRICAL LIVE CIRCUIT HAZARD

Do not touch electrically live parts. Disconnect, lockout and tag input
power supply before installing or servicing motor (includes accessory
devices).

WARNING:

ELECTRICAL LIVE CIRCUIT HAZARD

Shaft rotation produces voltage in PM motors even when motor is
disconnected from power source. Do not open terminal box or touch
unprotected terminals while the motor shaft is rotating. Failure to do so
may cause serious injury or death to personnel.

WARNING:

DISASSEMBLY APPROVAL REQUIRED

Due to powerful magnetic fields, disassembly and assembly of
permanent magnet motors should only be performed by the
manufacturer or specialized personnel authorized by the manufacturer.

WARNING:

MAGNETIC FIELD HAZARD

Permanent magnet motor rotors contain powerful magnetic fields.
Exposure to magnetic field may cause serious health hazards to persons

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