Rockwell Automation 1325R User Manual

Installation, Operation and Maintenance Manual
Small DC Motors
56 Frames
2 Small DC Motors

Receiving and Handling

ATTENTION: Only qualified electrical personnel familiar with the construction and operation of this equipment and the hazards
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involved should install, adjust, operate, and/or service this motor. Read and understand this manual in its entirety before proceeding. Failure to observe this precaution could result in personal injury or loss of life.

Acceptance

Unpack motor carefully and inspect for possible damage during shipment. Check packing materials and save any instruction tags or wiring diagrams found in the carton. Report any damages or shortages immediately to the local transportation agent.
ATTENTION: High voltageandrotating parts can cause serious or fatal injury. The use of electric machinery, like all other
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utilization of concentrated power and rotating equipment, can be hazardous. Installation, operation, and maintenance of electric machinery should be performed by qualified personnel. Familiarization with NEMA safety standards, national electrical code and sound local practices is recommended.

Installation

Mounting

Check nameplate data on motor before installing to assure the correct rating and that the available power supply agrees with the required motor power supply. Motor should be mounted on a firm foundation. If the foundation is not flat, use shims to prevent misalignment when tightening hold-down bolts. DC motors arc equipped with ball bearings and may be operated in any position. For anypositionotherthanbasedown, newdrainholesshould be provided so that condensation is allowed to run off. Location should be dry, clean and well ventilated for most satisfactory service. Be sure the possibility of oil seepage into the motor is prevented. Commutator end of the motor should be accessible so that brushes can be conveniently inspected.
ATTENTION: To guard against personal injury or death caused by contact with moving parts, guards (coupling, belt, chain, etc.)
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must be installed. Machines accessible to the public should be further guarded by screening, guard rails, etc.

Mounting Instructions for 56C & 140TC Face Mounted Motors

Before mounting a “C” face motor to a mating flange, be sure both surfaces and all mounting holes are smooth and free of debris.
When mounting into a quill type reducer, make sure the input and output shafts are coated with an anti-seize compound suitable for the application.
Small DC Motors 3
When mounting through a flexible coupling, verify that there is adequate clearance between the driven equipment shaft, the coupling interface and the motor shaft. Lack of clearance may result in binding of the shafting and premature bearing failure.
Always slide the motor tenon into the mating flange to its full depth before tightening the mounting bolts. Do not allow the motor to hang by the shaft extension while assembling it to the driven equipment (i.e. quill input gear case). This may bend or crease the shaft and damage any seals that are present.
Only use the proper mounting bolts. These should be 3/8”-16 threads per inch and sized for length such that engagement into the motor flange does not exceed 9/16”. For example, a gear case with a 3/8” flange thickness requires a bolt that is: 3/8” + 9/16” = 15/16” = Maximum Bolt Length
Since 15/16” is not a standard bolt length, a 7/8” bolt or a 1” bolt with a lockwasher can be used.
ATTENTION: To guard against motor damage such as premature failure and/or a loose assembly, use only mounting
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bolts that are the correct length. A bolt that is too long may cause damage to the motor.

Alignment

Shafts should be carefully aligned before tightening any couplings. Inspect couplings and shaft for paint, dirt or burrs. If necessary, remove with sandpaper for proper fit. Pulley or coupling should be carefully fitted. Do not hammer on shaft, pulley or coupling.

Application

Permanent Magnet “PM” motors are not always designed for across the line starting. This may cause loss of flux resulting in an increase in speed and possibly instability. Wound field motors can be started across the line with full applied voltage. However, for frequent starting or reversing, voltage should be reduced for normal brush and commutator life.
Dynamic or regenerative braking methods should not be used unless provisions are made to limit the maximum instantaneous current to a value not greater than the maximum allowable peak amperes shown on the nameplate. This also applies to plug reversing the PM motor.

Connections

All motors should be installed in accordance with the National Electric Code and local requirements. Fuses, thermal cutouts and other protective devices should be the proper size and rating to safely carry the load and to interrupt the circuit on overloads.
4 Small DC Motors
Type
Low Voltage Connection
ShuntStabilized Shunt and Compound
High Voltage Connection
Series
Low Voltage Connection
High Voltage Connection
Permanent Magnet
Thermostat (if furnished)
1, 2
1, 2
1, 2
1, 2
Rotation Facing Commutator End
CCW
+A1
–A2
+A1
A2
+A1
A2
+A1
A2 S1 S2 F22 S2 F22
+A1
A2 S1
–S2 +A1
–A2
CW
+F1 F11 –F2 F22
+F1 F11 F2 F22
S1 S2
+F1 F11 F2
+F1 F11 F2 F22 –S2 F22
P1 P2
–A1
+A2
–A1
+A2
A1
+A2
A1
+A2
S1
A1
+A2
S1
–A1 +A2
Connect in Series with Control Stop Device
+F1 F11 –F2 F22
+F1 F11 F2 F22
S1 S2
+F1 F11 F2
+F1 F11 F2
Ground Connection
1 Motors with single voltage fields do not have leads F11 & F22. Leads F11 & F22 may be
marked F3 & F4, respectively. Connect on low voltage field connection.
2 Consult motor nameplate to determine value of low and high voltage connection.
Earth Ground
Connection diagrams are shown above. Care must be taken to ensure that the dual-voltage shunt field is properly connected.
ATTENTION: Ground the machine properly to avoid serious injury to personnel. Grounding should be in accordance with the
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National Electrical Code and consistent with sound local practices.
Some DC motors are equipped with a thermostat inside the motor. This thermostat has a normally closed (NC) contact which opens if the motor temperature exceeds design limits due to extended overload operation. Leads from the thermostat are labeled P1 & P2 and should be connected in series with the drive “STOP” button (refer to the previous figure).
Small DC Motors 5
Important:When motors are provided with thermal protection (typically
thermostats), it is important to properly connect and apply the devices. This will ensure that the motor is properly protected from being operated if thermal limits are reached and/or exceeded. The control system must be configured to reduce the motor load and/or shut down the motor control system to allow the motor to cool to a level within acceptable operating ranges. If the motor is operated with the thermal protective devices tripped (indicating an over temperature condition), the motor insulation could be damaged and complete failure of the motor insulation is possible. In the event of motor failure due to an overtemperature condition, Rockwell Automation requires that motor thermal protective devices (when supplied) be adequately monitored and incorporated into the motor control system to maintain warranty. Failure on the part of the individual installing this equipment to take these steps will result in the factory warranty being voided.

Operation

Maintenance

These motors are inherently capable of operating over a wide range of speeds and loads. If the motor is not operated on the type of power supply for which it was designed, performance will differ from nameplate values and applicable standards.
The motor should start quickly. If it fails to start, the load may be too great, the applied voltage too low, or the motor improperly connected and/or the control misadjusted (check particularly current (torque) limit adjustment). In any case, immediately disconnect the power and investigate the cause.
While operating the motor, observe the performance. Any undue noise, overheating, sparking or erratic performance should be investigated and necessary corrective action taken to prevent serious damage.
The fundamental principle of electrical maintenance is keep the apparatus clean and dry. This requires periodic inspection of the motor, the frequency of inspection depending upon the type of motor and the service.
ATTENTION: Internal parts of this motor may be at line voltage even when motor is not rotating. Disconnect all AC line
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connections before contacting any internal part.
6 Small DC Motors

Bearings

Ball bearings are deep grooved, double shielded with sufficient lubricant packed into the bearings by the manufacturer for “life lubrication.” The initial lubricant is supplemented by a supply packed into larger reservoirs in the end shield at time of assembly. No grease fittings are provided. The initial lubrication is adequate for up to 5 years of operation under normal conditions.
Should it become necessary to replace bearings, the bearing bore and cavity should be thoroughly cleaned and repacked with approximately 1/2 teaspoonful of recommended grease.
Bearings should be removed with bearing pullers using a center insert in the end of the shaft to protect the shaft center. To reinstall ball bearings, either in a press or on the bench, pressure should be applied to the inner race by using a square faced sleeve or piece of pipe that will fit over the shaft, to avoid damaging the bearing. If a press is not available and a hammer is used, the blows should be transmitted against the sleeve by a block of wood or fiber.

Brushes

Check brushes to make certain that they move freely in the holders and make proper contact with the commutator. Re-place worn brushes. Give complete motor identification when ordering parts. New brushes should be pre-radiused to fit the commutator curvature. Blow out the carbon dust. Short brush life and poor commutation may be due to a rough commutator, a shorted armature, or poor undercutting of mica. Dirt and chemicals in the air are common causes of trouble.

Commutator

The commutator should remain a polished surface. Blackening may indicate rough or eccentric commutator. Occasional wiping (power off) with dry canvas or non-linting cloth may suffice. If rough or excessively dirty, smooth with very fine (00) sandpaper lightly with armature rotating. Never use emery cloth. Never allow the brushes to wear so short that spring tension is lost. The resultant sparking will seriously damage the commutator.
If frequent dressing is required, the cause should be found and corrected. A very rough commutator should be turned in a lathe, at high speed, with a sharp tool. Do not remove more copper than necessary. The mica should be undercut if necessary.
An authorized service shop is recommended for this work.
Small DC Motors 7

General

ATTENTION: Internal parts of this motor may be at line voltage even when motor is not rotating. Disconnect all AC line
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connections before contacting any internal part.
The following should be checked at regular intervals:
Windings should be dry and free of dust, grease, oil, and dirt. Windings
may be cleaned by suction cleaners or by wiping. Nozzles on suction type cleaners should be non-metallic. Gummy deposits of dirt and grease may be removed by using a commercially available low volatile solvent. Do not use gasoline or other inflammable solvents.
Terminal connections, assembly screws, bolts and nuts should be tight.
They may loosen if motor is not securely bolted and tends to vibrate.
Insulation resistance of motors in service should be checked periodically
at approximately the same temperature and humidity conditions to determine possible deterioration of the insulation. When such measurements at regular intervals indicate a wide variation, the cause should be determined. Motor should be reconditioned if the motor has been subjected to excessive moisture, or by rewinding or reinsulating if necessary. Enclosed motors require very little attention. Be sure that external air chamber of fan cooled motors does not become clogged with foreign material which will restrict passage of air.

Troubleshooting

If trouble develops in operation of motor, verify that:
1. The bearings are in normal condition and have been properly lubricated
with a high grade, ball bearing lubricant, free of dirt or grit. If dirt enters bearing, flush and relubricate.
2. There is no mechanical misadjustment to preventfree rotation of moving
parts of motor and drive.
3. All bolts and nuts are properly tightened.
4. Motor instructions have been carefully carried out.
5. The rated voltage is available at the motor terminals.
6. The voltage corresponds to the value stamped on the nameplate.
7. All connections are properly made in all circuits between motor and
control.
8. The overload and low voltage devices in control equipment, fuses or
other protective devices are in proper working order.
9. Brushes are in good condition and are making good con-tact with the
commutator.
10.The commutator is clean and has smooth polished surface.
11.No excessive overload exists on the motor. Compare line amperes at full
load with nameplate stamping.
Online Documentation
The latest motor information can be obtained from the Allen-Bradley Drives & Motors home page on the World Wide Web at:
http://www.controlmatched.com
Publication 1325R-UM001B-EN-P Ð August, 2001
Supersedes 1325R-UM001A-EN-P dated May, 2001 Copyright © 2001 Rockwell Automation. All rights reserved. Printed in USA.
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