Baldor MN605 Installation And Operating Manual

Integral Horsepower

DC Motor

Designed for operation with an SCR Control

2/09 Installation & Operating Manual MN605

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Important:
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Table of Contents

Section 1

General Information ................................................................. 1−1

Overview ...................................................................... 1−1

Important: ...................................................................... 1−1

Safety Notice: ................................................................... 1−1

Receiving ...................................................................... 1−2

Handling Handling ................................................................ 1−2

Storage ........................................................................ 1−3

Preparation for Storage ............................................................ 1−3

Removal From Storage ............................................................ 1−4

EMC Compliance Statement for European Union ........................................ 1−4

Section 2

Installation & Operation .............................................................. 2−1

Overview ....................................................................... 2−1

Location ....................................................................... 2−1

Mounting ....................................................................... 2−1

Alignment ....................................................................... 2−1

Doweling & Bolting ............................................................... 2−1

Guarding ....................................................................... 2−2

Power Connection ............................................................... 2−2

Conduit Box .................................................................... 2−2

Power ......................................................................... 2−2

Motor Connections ............................................................... 2−2

Thermostats .................................................................... 2−3

Blower Ventilation System .......................................................... 2−3

Initial Start-Up ................................................................... 2−4

Coupled Start-Up ................................................................ 2−4

Section 3

Maintenance & Troubleshooting ....................................................... 3−1

General Inspection ............................................................... 3−1

Relubrication & Bearings .......................................................... 3−1

Type of Grease .................................................................. 3−1

Lubrication Intervals .............................................................. 3−1

Lubrication Procedure ............................................................ 3−2

Brush Replacement .............................................................. 3−3

Brush Springs ................................................................... 3−3

Poor Brush Life .................................................................. 3−3

Brush Chatter or Bounce .......................................................... 3−3

Brush Sparking .................................................................. 3−3

Carbon Brushes For Special Operating Conditions ...................................... 3−3

Authorized Service ............................................................... 3−3

Humidity and Brush Wear .......................................................... 3−4

Commutator .................................................................... 3−4

Rapid Commutator Wear .......................................................... 3−4

Blowers & Filters ................................................................. 3−4

Guide To Commutator Appearance .................................................. 3−5

Continued on next page

Troubleshooting .................................................................. 3−6

iMN605

Armature Overheating ............................................................. 3−6

Field Coil Overheating ............................................................ 3−6

Excessive Load .................................................................. 3−6

Jogging and Repeated Starts ....................................................... 3−6

Heating ........................................................................ 3−6

Thermostat ..................................................................... 3−6

Reash Instructions .............................................................. 3−7

Accessories .................................................................... 3−8

Section 4

Connection Diagrams ............................................................... 4−1

ii MN605

Section 1

General Information

Overview This manual contains general procedures that apply to Baldor Motor products. Be sure to read and understand

the Safety Notice statements in this manual. For your protection, do not install, operate or attempt to perform
maintenance procedures until you understand the Warning and Caution statements.
A Warning statement indicates a possible unsafe condition that can cause harm to personnel.
A Caution statement indicates a condition that can cause damage to equipment.

Important: This instruction manual is not intended to include a comprehensive listing of all details for all procedures required

for installation, operation and maintenance. This manual describes general guidelines that apply to most of the
motor products shipped by Baldor. If you have a question about a procedure or are uncertain about any detail,
Do Not Proceed. Please contact your Baldor District Ofce for more information or clarication.

Before you install, operate or perform maintenance, become familiar with the following:

• NEMA Publication MG-2, Safety Standard for Construction and guide for Selection, Installation and
Use of Electric Motors and Generators.

• The National Electrical Code

• Local codes and Practices

Safety Notice: This equipment contains high voltage! Electrical shock can cause serious or fatal injury. Only qualied personnel

should attempt installation, operation and maintenance of electrical equipment.
Be sure that you are completely familiar with NEMA publication MG-2, safety standards for construction and
guide for selection, installation and use of electric motors and generators, the National Electrical Code and local
codes and practices. Unsafe installation or use can cause conditions that lead to serious or fatal injury. Only
qualied personnel should attempt the installation, operation and maintenance of this equipment.

WARNING: Do not touch electrical connections before you first ensure that power has been disconnected. Electrical

WARNING: Disconnect all electrical power from the motor windings and accessory devices before disassembling of

WARNING: Be sure the system is properly grounded before applying power. Do not apply AC power before you ensure

WARNING: Avoid extended exposure to machinery with high noise levels. Be sure to wear ear protective devices to

WARNING: Surface temperatures of motor enclosures may reach temperatures which can cause discomfort or injury

WARNING: Guards must be installed for rotating parts to prevent accidental contact by personnel. Accidental contact

WARNING: This equipment may be connected to other machinery that has rotating parts or parts that are driven by

WARNING: Do not by-pass or disable protective devices or safety guards. Safety features are designed to prevent

WARNING: Avoid the use of automatic reset devices if the automatic restarting of equipment can be hazardous to

WARNING: Be sure the load is properly coupled to the motor shaft before applying power. The shaft key must be

WARNING: Use proper care and procedures that are safe during handling, lifting, installing, operating and maintaining

WARNING: Pacemaker danger − Magnetic and electromagnetic fields in the vicinity of current carrying carrying

WARNING: Before performing any motor maintenance procedure, be sure that the equipment connected to the motor

WARNING: Motors that are to be used in flammable and/or explosive atmospheres must display the UL label on the

WARNING: Adjustable speed controls may apply hazardous voltages to the motor leads after power to the controller

WARNING: Use only UL/CSA listed explosion proof motors in the presence of flammable or combustible vapors or dust.
WARNING: Motors that are to be used in flammable and/or explosive atmospheres must display the UL label on the

shock can cause serious or fatal injury. Only qualified personnel should attempt the installation, operation
and maintenance of this equipment.

the motor. Electrical shock can cause serious or fatal injury.

that all grounding instructions have been followed. Electrical shock can cause serious or fatal injury.

reduce harmful effects to your hearing.

to personnel accidentally coming into contact with hot surfaces. When installing, protection should be
provided by the user to protect against accidental contact with hot surfaces. Failure to observe this
precaution could result in bodily injury.

with body parts or clothing can cause serious or fatal injury.

this equipment. Improper use can cause serious or fatal injury. Only qualified personnel should attempt to
install operate or maintain this equipment.

damage to personnel or equipment. These devices can only provide protection if they remain operative.

personnel or equipment.

fully captive by the load device. Improper coupling can cause harm to personnel or equipment if the load
decouples from the shaft during operation.

operations. Improper methods may cause muscle strain or other harm.

conductors and permanent magnet motors can result result in a serious health hazard to persons with
cardiac pacemakers, metal implants, and hearing aids. To avoid risk, stay way from the area surrounding a
permanent magnet motor.

shaft cannot cause shaft rotation. If the load can cause shaft rotation, disconnect the load from the motor
shaft before maintenance is performed. Unexpected mechanical rotation of the motor parts can cause
injury or motor damage.

nameplate along with CSA listed logo. Specific service conditions for these motors are defined in NFPA 70
(NEC) Article 500.

has been turned off. Verify the controller is incapable of delivering hazardous voltages and that the voltage
at the motor leads is zero before proceeding. Failure to observe this precaution may result is severe bodily
injury or death.

nameplate along with CSA listed logo. Specific service conditions for these motors are defined in NFPA 70
(NEC) Article 500.

1-1MN605

Safety Notice Continued

WARNING: UL Listed motors must only be serviced by UL Approved Authorized Baldor Service Centers if these

WARNING: This equipment is at line voltage when AC power is connected. Disconnect and lockout all ungrounded

WARNING: Rotating parts can cause serious or fatal injury. If relubrication is performed with the motor running, to

WARNING: Solvents can be toxic and/or flammable. Follow manufacturer’s safety procedures and directions.
WARNING: Space Heaters operate at line voltage. Disconnect power to space heaters before performing

WARNING: Thermostat contacts automatically reset when the motor has slightly cooled down. To prevent injury or

Caution: To prevent premature equipment failure or damage, only qualified maintenance personnel should

Caution: Do not over−lubricate motor as this may cause premature bearing failure.
Caution: Do not lift the motor and its driven load by the motor lifting hardware. The motor lifting hardware is

Caution: If eye bolts are used for lifting a motor, be sure they are securely tightened. The lifting direction should not

Caution: Do not use the coupling to compensate for poor alignment. This can result in vibration, noise, coupling

Caution: To prevent equipment damage, be sure that the electrical service is not capable of delivering more than

Caution: If a Motor Insulation test (High Potential Insulation test) must be performed, disconnect the motor from

Caution: Do not use Silicone grease or Sealing Compounds (RTV) on or in the vicinity of the motor or its air

Caution: Series wound motors must never be allowed to run with no load (broken belt etc.) An unloaded motor

Caution: Motors designed for forced ventilation must have cooling air when fields are excited at rated voltage.

motors are to be returned to a hazardous and/or explosive atmosphere.

conductors of the ac power line before proceeding. Failure to observe these precautions could result in
severe bodily injury or loss of life.

avoid injury do not contact any rotating parts.

maintenance work on motor. Failure to observe this precaution could result in severe bodily injury or
loss of life.

damage, the control circuit should be designed so that automatic starting of the motor is not possible
when the thermostat resets.

perform maintenance.

adequate for lifting only the motor. Disconnect the load (gears, pumps, compressors, or other driven
equipment) from the motor shaft before lifting the motor.

exceed a 20 ° angle from the shank of the eye bolt or lifting lug. Excessive lifting angles can cause damage.

wear, overloaded bearings and early failure.

the maximum motor rated amps listed on the rating plate.

any Speed Control or drive to avoid damage to connected equipment.

supply. Silicone vapor inside the motor will result in extremely rapid brush wear.

may reach destructive high speeds.

Installations having the air supply interrupted when the motor is not operating must have field
disconnected or field voltage reduced to 50% rated by means of field economizing resistor and relay or
motor insulation life will be significantly reduced.

If you have any questions or are uncertain about any statement or procedure, or if you require additional
information please contact your Baldor District Ofce.

Receiving Each Baldor Electric Motor is thoroughly tested at the factory and carefully packaged for shipment. When you

receive your motor, there are several things you should do immediately. Do not unpack until ready for use.

1. Observe the condition of the shipping container and report any damage immediately to the commercial
carrier that delivered your motor.

2. Verify that the part number of the motor you received is the same as the part number listed on your purchase order.

Lifting Magnet Generators

Caution: Do not lift the motor and its driven load by the motor lifting hardware. The motor lifting hardware is

Treat Baldor lifting magnet generators like motors during installation or maintenance.
Generally, they have standard compound self-excited elds. Standard magnetism is for counter-clockwise
rotation (facing the drive end of the motor). To reverse (operate clockwise), refer to the connection diagrams in
Section 4 of this manual.

adequate for lifting only the motor. Disconnect the load (gears, pumps, compressors, or other driven
equipment) from the motor shaft before lifting the motor.

Handling The motor should be lifted using the lifting lugs or eye bolts provided.

1. Use the lugs or eye bolts provided to lift the motor. Never attempt to lift the motor and additional
equipment connected to the motor by this method. The lugs or eye bolts provided are designed to lift only
the motor. Never lift the motor by the motor shaft or the hood of a WPII motor. If eye bolts are used for
lifting a motor, be sure they are securely tightened. The lifting direction should not exceed a 20° angle from
the shank of the eye bolt. Excessive lifting angles can cause motor damage.

2. To avoid condensation inside the motor, do not unpack until the motor has reached room temperature.
(Room temperature is the temperature of the room in which it will be installed). The packing provides
insulation from temperature changes during transportation.

3. When lifting a WPII (Weather Proof Type 2) motor, do not lift the motor by inserting lifting lugs into holes on
top of the cooling hood. These lugs are to be used for hood removal only. A spreader bar should be used
to lift the motor by the cast lifting lugs located on the motor frame.

1-2 MN605

4. If the motor must be mounted to a plate with the driven equipment such as pump, compressor etc., it may

not be possible to lift the motor alone. For this case, the assembly should be lifted by a sling around the
mounting base. The entire assembly can be lifted as an assembly for installation.
Do not lift the assembly using the motor lugs or eye bolts provided. Lugs or eye bolts are designed to lift
motor only. If the load is unbalanced (as with couplings or additional attachments) additional slings or other
means must be used to prevent tipping. In any event, the load must be secure before lifting.

Storage Storage requirements for motors and generators that will not be placed in service for at least six months from

date of shipment. To avoid condensation inside the motor, do not unpack until the motor has reached room
temperature. (Room temperature is the temperature of the room in which it will be installed). The packing provides
insulation from temperature changes during transportation.
Improper motor storage will result in seriously reduced reliability and failure. An electric motor that does not
experience regular usage while being exposed to normally humid atmospheric conditions is likely to develop rust
or rust particles on surrounding surfaces to contaminate the bearings. The electrical insulation may absorb an
excessive amount of moisture leading to the motor winding failure.
A wooden crate “shell” should be constructed to secure the motor during storage. This is similar to an export box
but the sides & top must be secured to the wooden base with lag bolts (not nailed as export boxes are) to allow
opening and reclosing many times without damage to the “shell”.
Minimum resistance of motor winding insulation is 5 Meg ohms or the calculated minimum, which ever is greater.
Minimum resistance is calculated as follows: Rm = kV + 1
where: (Rm is minimum resistance to ground in Meg−Ohms and
kV is rated nameplate voltage dened as Kilo−Volts.)
Example: For a 480VAC rated motor Rm =1.48 meg−ohms (use 5 MΩ).
For a 4160VAC rated motor Rm = 5.16 meg−ohms.

Preparation for Storage

1. Some motors have a shipping brace attached to the shaft to prevent damage during transportation. The

shipping brace, if provided, must be removed and stored for future use. The brace must be reinstalled to hold
the shaft rmly in place against the bearing before the motor is moved.

2. Store in a clean, dry, protected warehouse where control is maintained as follows:
a. Shock or vibration must not exceed 2 mils maximum at 60 hertz, to prevent the bearings from

brinelling. If shock or vibration exceeds this limit vibration isolation pads must be used.
b. Storage temperatures of 10°C (50°F) to 49°C (120°F) must be maintained.
c. Relative humidity must not exceed 60%.
d. Motor space heaters (when present) are to be connected and energized whenever there is a possibility

that the storage ambient conditions will reach the dew point. Space heaters are optional.

Note: Remove motor from containers when heaters are energized, reprotect if necessary.

3. Measure and record the resistance of the winding insulation (dielectric withstand) every 30 days of storage.
a. If motor insulation resistance decreases below the minimum resistance, contact your

Baldor District ofce.
b. Place new desiccant inside the vapor bag and re−seal by taping it closed.
c. If a zipper−closing type bag is used instead of the heat−sealed type bag, zip the bag closed instead of

taping it. Be sure to place new desiccant inside bag after each monthly inspection.
d. Place the shell over the motor and secure with lag bolts.

4. Where motors are mounted to machinery, the mounting must be such that the drains and breathers are fully

operable and are at the lowest point of the motor. Vertical motors must be stored in the vertical position.

Storage environment must be maintained as stated in step 2.

5. Motors with anti−friction bearings are to be greased at the time of going into extended storage with periodic

service as follows:
a. Motors marked “Do Not Lubricate” on the nameplate do not need to be greased before or during storage.
b. Ball and roller bearing (anti−friction) motor shafts are to be rotated manually every 3 months and greased

every 6 months in accordance with the Maintenance section of this manual.
c. Sleeve bearing (oil lube) motors are drained of oil prior to shipment. The oil reservoirs must be relled to

the indicated level with the specied lubricant, (see Maintenance). The shaft should be rotated monthly

by hand at least 10 to 15 revolutions to distribute oil to bearing surfaces.
d. “Provisions for oil mist lubrication” – These motors are packed with grease. Storage procedures are the

same as paragraph 5b.
e. “Oil Mist Lubricated” – These bearings are protected for temporary storage by a corrosion inhibitor.

If stored for greater than 3 months or outdoor storage is anticipated, connected to the oil mist system

while in storage. If this is not possible, add the amount of grease indicated under “Standard Condition”

in Section 3, then rotate the shaft 15 times by hand.

6. All breather drains are to be fully operable while in storage (drain plugs removed). The motors must be stored

so that the drain is at the lowest point. All breathers and automatic “T” drains must be operable to allow

breathing and draining at points other than through the bearings around the shaft.

Vertical motors should be stored in a safe stable vertical position.

7. Coat all external machined surfaces with a rust preventing material.

An acceptable product for this purpose is Exxon Rust Ban # 392.

8. Carbon brushes should be lifted and held in place in the holders, above the commutator, by the brush

holder ngers. The commutator should be wrapped with a suitable material such as cardboard paper as a

mechanical protection against damage.

1-3MN605

Non−Regreaseable Motors

Non−regreasable motors with “Do Not Lubricate” on the nameplate should have the motor shaft rotated
15 times to redistribute the grease within the bearing every 3 months or more often.

All Other Motor Types

Before storage, the following procedure must be performed.

1. Remove the grease drain plug, if supplied, (opposite the grease tting) on the bottom of each bracket prior

2. The motor with regreasable bearing must be greased as instructed in Section 3 of this manual.

3. Replace the grease drain plug after greasing.

4. The motor shaft must be rotated a minimum of 15 times after greasing.

5. Motor Shafts are to be rotated at least 15 revolutions manually every 3 months and additional grease

6. Bearings are to be greased at the time of removal from storage.

Removal From Storage

1. Remove all packing material.

2. Measure and record the electrical resistance of the winding insulation resistance meter at the time

3. Regrease the bearings as instructed in Section 3 of this manual.

4. Reinstall the original shipping brace if motor is to be moved. This will hold the shaft rmly against the

to lubricating the motor.

added every nine months (see Section 3) to each bearing.

of removal from storage. The insulation resistance must not be less than 50% from the initial reading
recorded when the motor was placed into storage. A decrease in resistance indicates moisture in the
windings and necessitates electrical or mechanical drying before the motor can be placed into service. If
resistance is low, contact your Baldor District ofce.

bearing and prevent damage during movement.

EMC Compliance Statement for European Union

The motors described in this instruction manual are designed to comply 2004/108/EC . These motors are
commercial in design and not intended for residential use. When used with converters, please consult
converter manufacturers literature regarding recommendations on cable types, cable shielding, cable shielding
termination, connection recommendations and any lters which may be recommended for EMC compliance.
For additional information, consult Baldor MN1383.

1-4 MN605

Section 2

General Information

Overview Installation should conform to the National Electrical Code as well as local codes and practices.

When other devices are coupled to the motor shaft, be sure to install protective devices to prevent future
accidents. Some protective devices include, coupling, belt guard, chain guard, shaft covers etc.
These protect against accidental contact with moving parts. Machinery that is accessible to personnel should
provide further protection in the form of guard rails, screening, warning signs etc.

Caution: Do not use Silicone grease or Sealing Compounds (RTV) on or in the vicinity of the motor or its air supply.

Silicone vapor inside the motor will result in extremely rapid brush wear.

Location

The motor should be installed in an area that is protected from direct sunlight, corrosives, harmful gases or
liquids, dust, metallic particles, and vibration. Exposure to these can reduce the operating life and degrade
performance. Be sure to allow clearance for ventilation and access for cleaning, repair, service and inspections.
Ventilation is extremely important. Be sure the area for ventilation is not obstructed.
Obstructions will limit the free passage of air. Motors get warm and the heat must be dissipated to prevent damage.
These motors are not designed for atmospheric conditions that require explosion proof operation.
They must NOT be used in the presence of ammable or combustible vapors or dust.
TEFC motors can be used for indoor or outdoor standard service. They cannot be used outdoors where they
would be exposed to freezing rain. Standard TEFC motors are not designed for atmospheric conditions requiring

Caution: Do not lift the motor and its driven load by the motor lifting hardware. The motor lifting hardware is

explosion-proof operation, such as ammable or combustible vapors or dust.

adequate for lifting only the motor. Disconnect the load (gears, pumps, compressors, or other driven
equipment) from the motor shaft before lifting the motor.

Mounting The motor must be securely installed to a rigid foundation or mounting surface to minimize vibration and maintain

alignment between the motor and shaft load. Failure to provide a proper mounting surface may cause vibration,
misalignment and bearing damage.
Foundation caps and sole plates are designed to act as spacers for the equipment they support. If these devices
are used, be sure that they are evenly supported by the foundation or mounting surface.
After installation is complete and accurate alignment of the motor and load is accomplished, the base should be
grouted to the foundation to maintain this alignment.
The standard motor base is designed for horizontal or vertical mounting. Adjustable or sliding rails are designed
for horizontal mounting only. Consult your Baldor distributor or authorized Baldor Service Center for further
information.

Alignment Accurate alignment of the motor with the driven equipment is extremely important.

1. Direct Coupling

For direct drive, use exible couplings if possible. Consult the drive or equipment manufacturer for more

information. Mechanical vibration and roughness during operation may indicate poor alignment.

Use dial indicators to check alignment. The space between coupling hubs should be maintained as

recommended by the coupling manufacturer.

2. End-Play Adjustment

The axial position of the motor frame with respect to its load is also extremely important. The motor bearings

are not designed for excessive external axial thrust loads. Improper adjustment will cause failure.

3. Pulley Ratio

The pulley ratio should not exceed 8:1. Consult your Baldor distributor or authorized Baldor Service Center

for further information.

Caution: Do not over tension belts. Excess tension may damage the motor or driven equipment.

4. Belt Drive

Refer to NEMA MG 1 section 14.07 or Baldor application section for the application of pulleys, sheaves,

sprockets, and gears. Align sheaves carefully to minimize belt wear and axial bearing loads (see End-Play

Adjustment). Belt tension should be sufcient to prevent belt slippage at rated speed and load. However, belt

slippage may occur during starting. Do not over-tension belts.

Caution: Series wound motors must never be allowed to run with no load (broken belt etc.) An unloaded motor may

reach destructive high speeds.

Doweling & Bolting

After proper alignment is veried, dowel pins should be inserted through the motor feet into the foundation.
This will maintain the correct motor position should motor removal be required. (Baldor motors are designed for
doweling.)

1. Drill dowel holes in diagonally opposite motor feet in the locations provided.

2. Drill corresponding holes in the foundation.

3. Ream all holes.

4. Install proper tting dowels.

5. Mounting bolts must be carefully tightened to prevent changes in alignment. Use a at 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.

2-1MN605

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 sufciently 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. Ground the motor by attaching a strap from an

Conduit Box

Power

Motor Connections

established ground point to the grounding bolt provided inside the conduit box.

For ease of making connections, an oversize conduit box is provided. The box can be rotated 360° in 90°
increments.

Connect the motor leads as shown on the connection diagram located on the name plate or inside the cover on
the conduit box. Be sure the following guidelines are met:

1. DC power is within ±5% of rated voltage (not to exceed 600VDC). (See motor name plate for ratings).

OR

2. DC eld power is within ±1% of rated voltage.

Terminal connections should be made as specied. See the connection diagrams located in Section 4 of this
manual. Tables 2−1 and 2−2 show the NEMA standard lead markings and the Accessory Markings.

Table 2-1 NEMA Standard Lead Markings

Lead Markings Motor

Armature A1, A2

Field (shunt) F1, F2, F3, F4, etc.

Field (series) S1, S2

Thermostat P1, P2, etc.

Space Heater H1, H2, H3, H4, etc.

Thermal Protector P1, P2, P3, P4, etc.

Resistance Temperature Detector (RTD) R1, R2, R3, R4, etc.

Optional Brush Monitor System A1Probe, A2Probe

Table 2-2 Accessory Markings

DC Tachometers + —

XPY 1 2 G

XC Red (1) Black (2) G

RL

AC Tachometers 45/90V Output

45V Red White

90V Red Black

Brake Coil Leads B1, B2, B3, etc.

Space Heater (Brake) H1, H2, H3, H4, etc.

Brake Interlock Switch BS1, BS2, BS3, etc.

2-2 MN605

Electrically

Isolated

Encoder

Standard Receptacle MS3112W12−10P
Standard Plug MS3116J12−10S

Figure 2-1 Encoder Connections

Color Codes for Optional

Baldor Encoder Cable

A
H
B

J
C
K
D
F

E

A
A
B

B
C
C
+5V
COMMON

A B

H

K

G J C

F E D

Thermostats The thermostat is a pilot circuit device used in a protective relay circuit. Thermostat ratings are given in Table 2−3.

Table 2-3 Thermostat Ratings

Maximum Current Ratings for Thermostats (Normally Open or Closed Contacts)

Voltage 125VAC 250VAC 24VDC Continuous Current All Voltages

Amperage 12A 8A 2A 2A

Blower Ventilation System

Before loading a force-ventilated motor, be sure that the blowers, cooling fans, or central air supply systems
are operating properly to supply cooling air to the motor. Air lters should also be in place. If you energize the
main elds with the motor at standstill, the blowers or external cooling systems must be left on. This will prevent
excessive heat buildup that will decrease the life of the insulation.
When using eld economy circuits to reduce the voltage to the main elds during standstill, blowers do not need
to be left on.
Blower motors should be checked for correct rotation. Don’t rely on feeling airow from the drive end of the
motor. Look at the outline drawing or rotation arrow shown on the blower housing. Refer to Figure 2-2.

Figure 2-2 View from Air Inlet (Motor is on Opposite Side)

Air Inlet

Housing

Impeller
Blades

Airflow

Size Motor Frame HP RPM Volts Phase Hz Amps

LM2 180 1/40 3000 230 1 60 0.4

LM3 180 1/8 3450 115/230 1 50/60 2.6/1.3

LM3 210-250 1/8 3450 208-230/460 3 50/60 0.66-0.60/0.30

LM4 280 1/3 3450 208-230/460 3 50/60 1.5-1.4/0.7

LM6 320-400 1 3450 208-230/460 3 50/60 3.1-3.0/1.5

LM8 504-506 3/4 1750 208-230/460 3 50/60 3.4-3.2/1.6

LM9 508-5012 3 3450 208-230/460 3 50/60 8.2-7.6/3.8

Note: Motor mounted blower units. Mount on commutator end (opposite drive end of motor. We supply blowers that are powered by totally enclosed motors (standard).

Blowers have a cast aluminum fan housing with washable, wire mesh filters.

Table 2-4 Electrical Data - Forced Ventilation Blower Units

2-3MN605

Table 2-5 Minimum Blower CFM for DPBV Motors (Drip Proof Blower Ventilated)

Blower Size Motor Frame

Size

LM2 180 55 0.50

LM3 180 150 1.45

LM3 210 175 1.45

LM3 250 215 0.78

LM4 280 350 0.88

LM6 320 780 2.80

LM6 360 780 2.80

LM6 400 820 2.50

LM8 504-506 1120 1.58

LM9 508-5012 2000 5.00

Blower CFM Blower Static Pressure

(In H

O)

2

Each motor nameplate is stamped with the above data for DPBV (less Blower), DPSV and TEPV enclosures.

Caution: Motors designed for forced ventilation must have cooling air when fields are excited at rated voltage.

Installations having the air supply interrupted when the motor is not operating must have field
disconnected or field voltage reduced to 67% rated by means of field economizing resistor and relay or
motor insulation life will be significantly reduced.

Initial Start-Up

If driven equipment can be damaged by rotating in the wrong direction, uncouple the motor from the load before
checking for rotation.

Caution: Series wound motors must never be allowed to run with no load (broken belt etc.) An unloaded motor may

reach destructive high speeds.

If the direction of rotation needs to be corrected, disconnect the input power supply and interchange the
appropriate leads. Refer to the motor connection diagrams in Section 4 of this manual.

1. The rst start-up and running of the motor should be with the motor uncoupled from the load.

2. Check the direction of rotation by momentarily applying power to the motor.

3. With the motor running, make sure it’s running smoothly without too much noise or vibration. If either are
present, shut down the motor immediately and nd the cause of the problem.

Coupled Start-Up

1. After the rst successful no load start-up, stop the motor and assemble the coupling.

2. Align the coupling and be sure it is not binding in any way.

3. The rst coupled start-up should be without load. Check to see that the driven equipment is not transmitting
any vibration back to the motor through the coupling or the base. Vibrations (if any) should be within
acceptable levels.

4. Run about 1 hour with driven equipment unloaded.

5. After completing these steps, the motor can now be loaded.

6. Do not exceed the value of armature nameplate amperes under steady continuous loads.

2-4 MN605

Section 3

Maintenance & Troubleshooting

General Inspection

Inspect the motor at regular intervals, approximately every 500 hours of operation or every 3 months, whichever
occurs rst. Keep the motor clean and the ventilation openings clear. The following steps should be performed at
each inspection:

1. Check that the motor is clean. Check that the interior and exterior of the motor is free of dirt, oil, grease,

2. Periodically measure the motor winding resistance to ensure that the integrity of the winding insulation has

3. Check all electrical connectors to be sure that they are tight.

4. Check for too much vibration or looseness. It may be caused by improper alignment, an unbalanced

5. Listen for unusual noises, especially in the area of the bearings. Also, rubbing or rumbling noises could

Note: Motors applied with rectied power supplies will often make a humming noise when operating normally. This

6. At start−up, check the tightness of the main and commutating pole bolts (external on the frame) as listed in

water, etc. Oily vapor, paper pulp, textile lint, etc. can accumulate and block motor ventilation. If the motor is
not properly ventilated, overheating can occur and cause early motor failure.

been maintained. Record the motor winding resistance. Immediately investigate any signicant drop in
insulation resistance.

coupling sheave, damaged motor bearings, or loose mounting bolts. Excessive vibration will damage the
motor bearings, brushes and commutator.

be signs of internal damage. Check for loose parts on the motor such as thru bolts, hold down bolts, bad
alignment of hoods, etc. An unbalanced armature or load may also cause noise.

is even more noticeable at lower operating speeds. If you can hear a growling or erratic hum, the power
supply should be checked for proper operation and phase balance. Improper adjustment or functioning of
the power supply can cause overheating of the motor and shorten its life.

Table 3-1. Loose pole bolts could be a source of unpleasant noise when rectied power runs the motor.

Table 3-1 Torque Specifications for Commutating and Main Pole Bolts

Frame Bolt Size Torque (lb-ft)

180AT 3/8 - 16 24 - 30

210AT 3/8 - 16 24 - 30

250AT 3/8 - 16 24 - 30

280AT 1/2 - 13 60 - 75

320AT 1/2 - 13 60 - 75

360AT 3/8 - 16 24 - 30

400AT 3/8 - 16 24 - 30

500AT 1/2 - 13 60 - 75

Lubrication & Bearings

Bearing grease will lose its lubricating ability over time, not suddenly. The lubricating ability of a grease (over time)
depends primarily on the type of grease, the size of the bearing, the speed at which the bearing operates and the
severity of the operating conditions. Good results can be obtained if the following recommendations are used in

Type of Grease

Lubrication Intervals

* Lubrication intervals are for ball bearings. For roller bearings, divide the listed lubrication interval by 2.

your maintenance program.

A high grade ball or roller bearing grease should be used. Recommended grease for standard service conditions
is Polyrex EM (Mobil).
Equivalent and compatible greases include:
Texaco Polystar, Rykon Premium #2, Pennzoil Pen 2 Lube and Chevron SRI−2.

− Maximum operating temperature for standard motors = 110° C.

− Shut−down temperature in case of a malfunction = 115° C.

Recommended lubrication intervals are shown in Table 3-2. It is important to realize that the recommended
intervals of Table 3-2 are based on average use. Refer to additional information contained in Tables 3-3 and 3-4.

Table 3-2 Lubrication Intervals *

NEMA / (IEC) Frame Size Base Speed - RPM

>2500 1750 1150 <800

Up to 210 incl. (132) 5500 Hrs. 12000 Hrs. 18000 Hrs. 22000 Hrs.

Over 210 to 280 incl. (180) 3600 Hrs. 9500 Hrs. 15000 Hrs. 18000 Hrs.

Over 280 to 360 incl. (225) * 2200 Hrs. 7400 Hrs. 12000 Hrs. 15000 Hrs.

Over 360 to 500 incl. (300) *2200 Hrs. 3500 Hrs. 7400 Hrs. 10500 Hrs.

3-1MN605

Table 3-3 Service Conditions

Severity of Service Ambient Temperature

Maximum

Standard 40° C Clean, Little Corrosion Deep Groove Ball Bearing

Severe 50° C Moderate dirt,

Extreme >50° C * or Class H Insulation Severe dirt, Abrasive

Low Temperature <-30° C ** All Bearings

* Special high temperature grease is recommended (Dow Corning DC44). Note that Dow Corning DC44 grease does not mix with other grease types.
Thoroughly clean bearing & cavity before adding grease.
** Special low temperature grease is recommended (Aeroshell 7). Different brushes may also be required.
Contact your local Baldor district office or an authorized Baldor service center for technical assistance.

Atmospheric
Contamination

Corrosion

dust, Corrosion

Type of Bearing

Ball Thrust, Roller

All Bearings

Table 3-4 Lubrication Interval Multiplier

Severity of Service Multiplier

Standard 1.0

Severe 0.5

Extreme 0.1

Low Temperature 1.0

Table 3-5 Bearings Sizes and Types

Frame Size
NEMA (IEC)

Up to 210 incl. (132) 6307 80 21 0.30 (8.4 ) 0.6 2.0

Over 210 to 280 incl. (180) 6311 120 29 0.61 (17 ) 1.2 3.9

Over 280 to 360 incl. (225) 6313 140 33 0.81 (23 ) 1.5 5.2

Over 360 to 500 incl. (300) NU319 200 45 2.12 (60) 4.1 13.4

Bearing Description (These are the Large bearings (Shaft End) in each frame size)

Bearing

OD
D mm

Width
B mm

Weight of Grease to
add oz (Grams) *

Volume of grease to be added

in

3

teaspoon

* Weight in grams = .005 DB

Lubrication Procedure

Be sure that the grease you are adding to the motor is compatible with the grease already in the motor. Consult
your Baldor distributor or an authorized service center if a grease other than the recommended type is to be used.

Caution: To avoid damage to motor bearings, grease must be kept free of dirt. For an extremely dirty environment,

contact your Baldor distributor or an authorized Baldor Service Center for additional information.

With Grease Outlet Plug

1. Clean all grease ttings.

2. Remove grease outlet plug.

3. If motor is stopped, add the recommended amount of grease.
If motor is to be greased while running, a slightly greater quantity of grease will have to be added.
Add grease slowly until new grease appears at shaft hole in the endplate or purge outlet plug.

4. Re-install grease outlet plug.

Without Grease Outlet Plug

1. Disassemble motor.

2. Add recommended amount of grease to bearing and bearing cavity. (Bearing should be about 1/3 full of
grease and outboard bearing cavity should be about 1/2 full of grease.)

Note: Bearing is 1/3 full when only one side of bearing is completely full of grease.

3. Assemble motor.

Sample Lubrication Determination

Assume - NEMA 286T (IEC 180), 1750 RPM motor driving an exhaust fan in an ambient temperature of 43° C and
the atmosphere is moderately corrosive.

1. Table 3-2 list 9500 hours for standard conditions.

2. Table 3-3 classies severity of service as “Severe”.

3. Table 3-4 lists a multiplier value of 0.5 for Severe conditions.

4. Table 3-5 shows that 1.2 in

3

or 3.9 teaspoon of grease is to be added.

Note: Smaller bearings in size category may require reduced amounts of grease.

3-2 MN605

Brush Replacement

Do not change brush grades or suppliers without rst contacting Baldor for technical assistance.
Brush life will vary greatly due to motor load conditions and the operating environment. The brush pigtail leads
should be checked for secure connection to the brush support stud. Brushes should be replaced when their
pigtails touch the top of the brush holder.

When replacing brushes, proper seating is important!

1. Wrap a strip of coarse grit (60) sandpaper, rough side out, around the commutator and under the brush
holder. (Do not use metal oxide based sandpaper or emery cloth that contains electrically conductive
materials).

2. Slide the new brush into the holder and snap the spring clip in place.

3. Rotate the armature slowly in the direction of normal motor rotation.

4. Remove the brush and inspect the face. The brush should be seated over 90% of the face area and
completely seated from leading to trailing edge.

Brushes should move freely in their holders. If brushes stick, it is usually due to built up dirt and oil.
Brushes should be inspected on occasion to see that they are long enough to press rmly against the
commutator. Brush springs should have equal tension. Only brushes of the same size, grade and shape as those
originally supplied should be used.
All motors have their brushes set on neutral before leaving Baldor’s factory. After replacing the brush holder,
realign it to the factory neutral mark.
When replacing a turned-down commutator in the motor with a new commutator, the brush holder assembly must
be adjusted. Keep 1/16” clearance between the bottom of the brush holder and commutator. The brush holder
assembly is designed with a nut/bolt guide assembly for ease in positioning of the brush-box.
During periodic inspections, check that electrical connections are tight and properly insulated.

Brush Springs

Brush springs should be inspected for proper tension during brush replacement. If the spring shows a loss in
tension, it should be replaced. Routine replacement of brush springs is recommended with every third set of
brushes.

Poor Brush Life

Poor brush life may be caused by overloading, brushes operating at higher than their rated speed, or very light
electrical loads. These can be corrected by using a brush with greater current-carrying capacity for overloads.
Friction-reducing treatments reduce wear on high speed applications. Where light loading is the cause, the
answer may be to remove some brushes from the motor (with multiple brushes per pole).
Another is to install brushes with a higher content of graphite that can handle the lower current and still
lm properly. Poor brush life is generally not related to the “softness” or “hardness” of the brush.
Do not change brush grades or the number of brushes per pole. Doing so may void the warranty and
make the motor unsafe to operate. Contact your local Baldor district ofce or an authorized Baldor
service center for technical assistance.

Brush Chatter or Bounce

Brush chatter or bouncing can be caused by vibration from an external source. This may be a bad gearbox
coupling or condition, or insecure mounting of the motor. Stronger carbon grades are available that provide more
capacity for the brush to resist vibration. It is always best to x the cause of the problem.

Brush Sparking

Excessive sparking of brushes may be due to electrical causes such as an overload or a very unstable DC power
supply. Mechanical causes include a at spot on the commutator or external vibration.
Changing to a better brush grade, or a split-brush design may be required.

Carbon Brushes For Special Operating Conditions

Sometimes, there are problems if motor operation requires a different design or grade of carbon brush than what
was installed when the motor was built. These special operating conditions include long periods of operation with
loads that are signicantly greater or less than rated load capacity. Also, operation in in the presence of certain
chemicals, or extreme temperature and humidity can degrade brush performance.
Generally, poor brush life or commutator wear can occur if one or more of the above conditions exist. The brush
used doesn’t match the operating conditions.
Baldor offers optional brush grades for the above conditions and has replacement brushes available to retrot
motors. Contact your local Baldor District Ofce or an Authorized Baldor Service Center for technical assistance.
Do not change brush grades or the number of brushes per pole. Doing so may void the warranty and make
the motor unsafe. Contact your local Baldor district ofce or an authorized Baldor service center for technical
assistance.

Authorized Service

Baldor catalog 505 (and the Baldor CD−ROM) lists service shops authorized to service Baldor DC motors.
Contact your local Baldor District Ofce for more information.

3-3MN605

Humidity and Brush Wear

This curve represents 2 grains of water per cubic foot of dry air or 4.6 grams per cubic
meter of dry air.

Zone of Safe Brush Operation

110

100

90

80

70

60

50

Temperature Degrees F

40

30

Danger Zone

Too Low Humidity

10 20 30 40 50 60 70 80 90 100

Percent Relative Humidity

45

40

35

30

25

20

15

10

Temperature Degrees C

5

0

Caution: Be very careful when repainting a drip proof motor. Do not get any paint on the commutator. Paint on

the commutator will show up as black marks in brush tracks. Also, excessive brush sparking or erratic
operation can be caused by paint or other material on the commutator.

Commutator

After several hours of operation, the commutator surface under the brush should take on a darker bronze
color. This is due to self-generated lm caused by normal commutation. This coloration should be even,
without blotches or black areas. A shiny copper color or black streaks in the brush tracks are signs of improper
commutation or contamination by a foreign material. Contact Baldor for assistance in correcting these problems.
If the commutator becomes rough and burned, or becomes black, it should be cleaned of dirt and carbon
particles. This can be done by wiping it with a dry, lint-free cloth. Also vacuuming or blowing out the motor with
a dry air supply are suitable cleaning methods. Do not use solvents or cleaning solutions on the commutator.
To remove spots or contamination that will not wipe off, wrap a strip of coarse (60# grit) sandpaper around the
commutator. Then rotate the armature back and forth by hand. Do not use emery cloth as this contains electrically
conductive materials.
Another method of commutator resurfacing is to use a commercially available commutator dressing stone.
This should only be done by trained and experienced people. This stone should be taped or attached to the end
of a stick made of electrically insulated material. The motor should be run at about half speed and the stone
applied lightly to the commutator surface. This operation must be done with no load on the motor.
The surface of the commutator should be smooth and round. This can be checked while the motor is running at
low speed. Press lightly on one brush with an insulated stick. Do not use a lead pencil as this contains electrically
conductive graphite. If you feel movement of the brush, it suggests a worn or uneven commutator. The armature
must be removed from the motor and the commutator machined by a qualied repair shop.

Rapid Commutator Wear

Light electrical loads and contamination are the usual causes of rapid commutator wear.
Light loading may require the removal of some brushes on motors with multiple brushes per pole.
Sometimes a low current density brush grade is used. There are also brushes that have a mild polishing action.
These prevent certain chemicals, especially chlorine and silicone, from attacking the commutator.
Brushes, are available for use in plastic extruder applications where PVC is present. Usually, you do not have to
change the design or grade of the brushes on new motors unless special operating conditions exist.
Do not change brush grades or the number of brushes per pole. Doing so may void the warranty and make
the motor unsafe. Contact your local Baldor district ofce or an authorized Baldor service center for technical
assistance.

Blowers & Filters

Do not use silicone RTV around DC motors as commutator surface damage can occur. Intake lters on blowers
and louvers of drip proof motors should be cleaned to remove any dust or foreign matter.
Canister type lters should be replaced when dirty. Failure to keep air intakes clear will cause overheating and
premature failure of the insulating system.

3-4 MN605

Guide To Commutator Appearance (This chart courtesy of Helwig Carbon Products, Inc., Milwaukee, WI)

Light Film: Indicates good brush
performance. Light load, low humidity,
brush grades with low filming rates, or film
reducing contamination can cause lighter
color.

Streaking: Results from metal transfer to
the brush face. Light loads and/or light
spring pressure are most common causes.
Contamination can also be a contributing
factor.

Medium Film: Is the ideal commutator
condition for maximum brush and
commutator life.

Threading: Is a further development of the
streaking condition as the metal
transferred becomes work hardened and
machines into the commutator surface.
With increased loads and increased spring
pressure this condition can be avoided.

Heavy Film: Results from high load, high
humidity or heavy filming rate grades. Colors
not in the brown tones indicate contamination
resulting in high friction and high resistance.

Grooving: May result from an overly
abrasive brush grade. The more common
cause is poor electrical contact resulting in
arcing and the electrical machining of the
commutator surface. Increased spring
pressure reduces this electrical wear.

Copper Drag: Develops as the commutator
surface becomes overheated and
softened. Vibration or an abrasive grade
causes the copper to be pulled across the
slots. Increased spring pressure will
reduce commutator temperature.

Bar Edge Burning: Results from poor
commutation. Check that brush grade has
adequate voltage drop, that the brushes
are properly set on neutral and that the
interpole strength is correct.

Slot Bar Marking: Results from a fault in
the armature windings. The pattern relates
to the number of conductors per slot.

3-5MN605

Troubleshooting

Armature Overheating

Field Coil Overheating

Excessive Load

Jogging and Repeated Starts

Heating

Thermostat

Excessive overloads will cause a noticeable odor of overheated varnish or charred insulation. The commutator
may eventually become blackened and pitted and the brushes burned. This overheating may be general and
uniform. To cure, remove the overload and rewind or replace armature if damaged beyond use.
An open-circuited armature coil will cause ashing at the commutator. Two adjacent bars will show severe
burning and a resulting overheated armature. Short-circuited coils or commutator bars may cause local heating
that could destroy the insulation at that spot. This may result in the burning of the armature coils, banding or
commutator bars.
Grounds in the armature circuit may be found by measuring the motor winding resistance. If the armature s
grounded, less than 1 meg ohm is measured. These tests should be done by experienced and qualied
personnel.

The blowers or external cooling systems should be left in operation if the main eld windings remain fully
energized with the motor at standstill. Failure to do so may cause too much heat build-up which could cause
reduced insulation life.
When using eld economy circuits to reduce voltage to the main elds during standstill, blowers do not need to
be operating. The most common failure with overheated eld coils is a short in one or more of the shunt coils.
Shorted coils show less than half the line voltage for two pole motors. This is with the elds connected for high
voltage (in series). Shorted four pole motor coils will read less than 1/4 of the line voltage with the coils connected
for high voltage (in series).
A grounded coil may cause overheating. This defect may be tested as shown by the ground test for an armature.
With brushes lifted, measure the motor winding resistance. If the armature is grounded, less than 1 meg ohm is
measured.
An open eld coil on a motor will cause the armature to have no torque. The motor may run at a very high speed
at no load. The commutator may be ashing. To locate an open coil, apply line voltage to the shunt coils (brushes
lifted). A voltmeter will show no reading across a good coil. It will show about the line voltage across the open
coil.
These tests should be done by experienced and qualied personnel. If you nd any of the above defects, don’t
run the motor. First contact your local Baldor District Ofce or an Authorized Baldor Service Center for repairs.

Excessive load may be found by checking the DC armature ampere input and comparing it with the rating on
the nameplate. An excessive load may prevent the motor from starting or accelerating to full load speed. It could
nally result in premature failure of the motor or control. Be sure to use an averaging type ammeter if the motor’s
power is coming from a rectier or SCR control.

Repeated starts or jogs of motors may reduce the life of the brushes and winding insulation. The heat produced
by excessive starting may be more than what can be dissipated by the motor under a constant full load
conditions. If you must frequently start or jog a motor, you should check the application with the local Baldor
District Ofce.

Duty cycle and maximum ambient temperature are shown on the nameplate of the motor. If there is any question
about safe operation, contact the local Baldor District Ofce.
Motor overheating may be caused by improper ventilation, excessive ambient temperature, dirty conditions or an
inoperable blower or dirty lter. Electrical causes may be due to excess current caused by an overload or over­voltage to the elds.

Most stock Baldor DC motors 180 frame and above have a standard temperature-sensing thermostat mounted to
their interpole winding. This normally closed thermostat opens when the temperature limit is exceeded. Another
option available is a normally open thermostat that closes with temperature.
On blower cooled or separately ventilated motors, the protection capabilities of the thermostats are greatly
reduced at low speeds. This is because the interpoles have the same amount of heat transfer regardless of
speed. Armature heat transfer is less at low speed. There is less internal air turbulence at low speeds causing
higher temperatures at the armature.
The thermal time constant for interpoles can be as much as ve times longer than the armature’s time constant.
Because of this, the thermostat cannot be relied upon to protect the armature during extreme overloads lasting a
short time.
The ripple of the rectied power supply and manufacturing tolerances of mounting the device affect the
thermostat’s accuracy.
For thermostat contact ratings, refer to Thermostats in Section 2 of this manual.

3-6 MN605

Table 3-6 Troubleshooting Chart

Symptom Possible Causes Possible Solutions
Motor will not start Usually caused by line trouble, such

as, single phasing at the starter.

Excessive humming High Voltage. Check input line connections.

Loose pole pieces. Torque the bolts as specified in Table 3-1.

Motor Over Heating Overload. Compare actual amps

(measured) with nameplate rating.

Improper ventilation. Check external cooling blower to be sure air is moving properly across cooling fins.

Armature rubbing on stator. Check air gap clearance and bearings.

Field over voltage. Check input voltage.
Full voltage on field with motor stopped. Reduce field voltage to 60% with field economy circuit in the control.
Grounded winding. Perform dielectric test and repair as required.
Improper connections. Inspect all electrical connections for proper termination, clearance, mechanical strength and electrical

Bearing Over Heating Misalignment. Check and align motor and driven equipment.

Excessive belt tension. Reduce belt tension to proper point for load.
Excessive end thrust. Reduce the end thrust from driven machine.
Excessive grease in bearing. Remove grease until cavity is approximately 3/4 filled.
Insufficient grease in bearing. Add grease until cavity is approximately 3/4 filled.
Dirt in bearing. Clean bearing cavity and bearing. Repack with correct grease until cavity is approximately 3/4 filled.

Vibration Misalignment. Check and align motor and driven equipment.

Rubbing between rotating parts and
stationary parts.

Armature out of balance. Have armature balance checked are repaired at your Baldor Service Center.
Resonance. Tune system or contact your Baldor Service Center for assistance.

Noise Foreign material in air gap or

ventilation openings.

Growling or whining Bad bearing. Replace bearing. Clean all grease from cavity and new bearing.

Check source of power. Check overloads, fuses,
controls, etc.

Locate and remove source of excessive friction in
motor or load.
Reduce load or replace with motor of greater capacity.

Check blower for proper direction of rotation.
Check motor brush covers to ensure they are solid on the commutator end and that they are not
louvered.
Check filter for dirt, clean or replace.
Excessive dirt build-up on motor. Clean motor.

Tighten Thru Bolts that hold the endplates to frame.
Torque the pole bolts as specified in Table 3-1.

continuity. Refer to connection diagram.

Isolate and eliminate cause of rubbing.

Remove armature and foreign material. Reinstall armature. Check insulation integrity. Clean ventilation
openings.

Repack with correct grease until cavity is approximately 3/4 filled.

Reflash Instructions

Instructions to reash the residual magnetism for Lifting Magnet Generators only. These generators are self−
exciting. If voltage will not build up, it is possible the residual magnetism is insufcient to initiate excitation. This
procedure is to restore sufcient residual magnetism to self excite.

Note: Loss of residual magnetism can be caused by misconnection (reversing the connections) of F1 and F4.

1. Disconnect F1 and F4. All other leads may remain connected.

2. Connect 24 to 40VDC power source positive lead to F1 and negative to F4.
DC source may be batteries, a DC welder (not AC) or rectied AC.

3. Drive generator at rated RPM.

4. Measure the voltage across A1 and A2. Voltage should be 150 to 200% of F1 to F4 voltage. When A1 to A2
voltage level reaches this level (approximately 30 seconds) carefully remove the source leads, an arc may be
present during disconnect.

5. Stop the generator.

6. Reconnect F1 and F4 as shown in the DC Generator Connection Diagram. Rotation is viewed from opposite
drive end (commutator end) A1 is positive for CCW rotation. A2 is positive for CW rotation. S1 is always
negative.

DC Generator Connection Diagram

Shunt Fields

ARM

Shown for CCW (counterclockwise) rotation, (viewed from opposite drive end or
commutator end). For CW (clockwise) rotation, interchange leads A1 and A2.

Compound Wound Short Shunt Connection

COMM Field

Series Field

3-7MN605

Accessories The following list shows some accessories available through Baldor’s Mod Express or available on custom

manufactured motors. Contact your Baldor supplier for information on each additional accessory or those listed
below.

Bearing RTD

Bearing Thermocouples

Bearing Thermostat

Blowers with Filters

Brush Wear Indicator

Condensation Drains & Breathers

Conduit Boxes

Cord & Plug Assembly

Drip Covers

Fan Cover & Lint Screen

Nameplate

Roller Bearings

Rotation Arrow Labels

Slide Bases

Space Heater

Stainless Hardware

Tachometers

Transparent Brush Inspection

Winding RTD

Winding Thermocouples

Winding Thermostat

RTD (Resistance Temperature Detector) devices are used to measure or monitor the temperature of the motor
bearing during operation.

Used to measure or monitor bearing temperatures.

Temperature device that activates when bearing temperatures are excessive. Used with an external circuit to warn
of excessive bearing temperature or to shut down a motor.

Available to increase the constant torque speed range of DPFG motors. This increases the continuous operating
torque range at low speeds.

Provides a warning when the brushes have worn down to the level where they need to be replaced (before
damage to the commutator).

Stainless steel drains and separate breathers are available.

Optional conduit boxes are available in various sizes to accommodate accessory devices.

Adds a line cord and plug for portable applications.

Designed for use when motor is mounted in a vertical position. Contact your Baldor distributor to
conrm that the motor is designed for vertical mounting.

To prevent build-up of debris on the cooling fan.

Additional stainless steel nameplates are available.

Recommended for belt drive applications with a speed of 1800 RPM or less.

Rotation arrows are supplied on motors designed to operate in one direction only. Additional rotation arrows are
available.

Allows easy belt adjustment while maintaining correct pulley and belt alignment.

Added to prevent condensation of moisture within the motor enclosure during periods of shut down or storage.

Stainless steel hardware is available. Standard hardware is corrosion resistant zinc plated steel.

DC, AC and digital outputs are available. These can be mounted to our motors or shipped separately.
Tachs help the SCR control achieve more precise speed regulation than by armature feedback alone.

For easy brush inspection and commutation monitoring without disassembly of the motor.

RTD (Resistance Temperature Detector) devices are used to measure or monitor the temperature of the motor
winding during operation.

Used to measure or monitor winding temperatures.

Temperature device that activates when winding temperatures are excessive. Used with an external circuit to
warn of excessive winding temperature or to shut down a motor.

3-8 MN605

Section 4

Connection Diagrams

Low Voltage connection Shunt Field

F1

F3

Interpole

Armature

A1

+

F2

F4

A2 S2S1

Series Motor CCW Rotation
(Facing Commutator End)

Shunt Field

F2

F3

F1

Field Reversing Series Motor

Series Field

−

Armature Reversing

Compound and Stabilized Motors

High Voltage connection Shunt Field

F2

Armature

A1

+

F3

Interpole

A2 S1S2

Series Motor CW Rotation
(Facing Commutator End)

Shunt Field

F2

F3

F4

Series Field

−

Interpole Series Field

Armature

F1

A1

+

A2 S2S1

Compound or Stabilized Shunt Motor
CCW Rotation (Facing Commutator End)
High Voltage Field Connection

Interpole Series Field

Armature

− −

F1

A2

+

1A4F

S2S1

Compound or Stabilized Shunt Motor
CW Rotation (Facing Commutator End)
High Voltage Field Connection

F4

4-1MN605

Field Reversing Shunt Motor

Shunt Field

F2

F3

Interpole

Armature

F1

A1

+

Shunt Motor CCW Rotation
(Facing Commutator End)
High Voltage Field Connection

Field Reversing Shunt Motor

Shunt Field

F3

F2

Interpole

Armature

F4

A1

+

Shunt Motor CW Rotation
(Facing Commutator End)
High Voltage Field Connection

DC Generator Connection Diagram

Compound Wound Short Shunt Connection

A2

A2

F4

−

F1

−

Shunt Field

F1

Rheostat

A1

+

F2 F3 F4

Comm. Field

CCW Rotation

A2

Series Field

S2 S1

−

(Facing Commutator End)
For CW Rotation, Interchange Leads A1 and A2.

4-2 MN605

Baldor Electric Company

P.O. Box 2400, Fort Smith, AR 72902-2400 U.S.A., Ph: (1) 479.646.4711, Fax [phone], International Fax [phone]

www.baldor.com

© Baldor Electric Company
MN605

All Rights Reserved. Printed in USA.

2/09