Motor Installation and Maintenance Manual
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Transcript of Motor Installation and Maintenance Manual
Installation and Maintenance Manual
CONTENTS
TOPICS PAGES
2
333456
899999
1010
11111111
1212141415
- Insulation Resistance
- Foundation & Mounting- Drain Holes- Motor Alignment- Fitting Half Coupling/Pulley- Slide Rails & Belt Drives- V-Belt coupling- Direct connected- Vibrations
- Terminal Box- Earthing- Direction Of Rotation- Reduced Voltage Starting- Voltage And Frequency Variation- Connections- Precautions- T Time
- Cleaning- Checks- Drying Motor- Reassembly
- Bearing Mounting- Bearing Removal- Lubrication- Grease valve Lubrication- Relubrication chart
coupling 7
hot
Reception 1Storage 1Pre installation checks 2
Installation & Commissioning 2
7Motor Protection 8Electrical Connection 8
Operation With Inverters 10Maintenance 11
Bearing 12
Troubleshooting Chart 16Exploded view 21
! On receipt of the motor, please check for transit damage, if any.
! Unpack motor carefully and check motor for breakage and missing parts. Check all data on the rating plate to see that they correspond to your order. Make a special point of checking voltage, and the connection method. (i.e. star or delta)
! If any damage to the motor is observed obtain a damage certificate from the transporter within 24 hours.
! Please report damage, if any, to ABB local office through whom the motor has been purchased within 48 hours in order to observe the time limit for filing claims.
! While reporting damage please mention motor serial number and if possible the document no. for quicker response.
! Turn shaft by hand to check free rotation.
If the motor is not installed immediately
RECEPTION
STORAGE
the following storage method has to be employed:
Motor to be stored indoors in a clean and dry atmosphere. Keep covered to eliminate airborne dust and dirt. Cover openings for ventilation, conduit connections, etc. to prevent entry of undesirable elements(e.g. rodents). The temperature of the store room
0should be kept 5 C above ambient temperature and as constant as
CAUTION
possible as temperature swings cause condensation. To prevent bearing damage the storeroom should be free from vibration.
Machined parts should have a protective coat of rust inhibitor during storage period. In case of long storage, periodic examination should be carried out and fresh inhibitor should be applied where necessary.
In case of storage for a long period, the spare bearing should be given a coating of light oil or grease and packed in polythene bags for protection against moisture .
Anti-condensation heaters, if fitted, should be energised if motor is idle.
Once per month, rotate shaft several turns to distribute grease in the bearings as it tends to settle at the bottom of the housings. If the unit has been stored more than a year add grease before start up.
Do not roll or drag motor on floor. Avoid jerks and jolts to increase the life of the bearings. Do not keep a totally enclosed fan cooled motor in vertical position with external cover as base.
Eyebolts are intended for lifting of motor only. These lifting devices must never be used when lifting or handling the motor with other equipment's (i.e. pumps, gear boxes, fans or other driven equipment) as a single unit. Eyebolt lifting capacity ratings is based on a lifting alignment coincident with the centreline.
1
CAUTION
WARNING
Inspect the name plate details and ensure that: the voltage and frequency correspond to that of the supply. HP & rpm correspond to that of the driven machine.
Remove the anti-corrosion agent on shaft with kerosene/thinner. Do not use sandpaper or scraper.
INSULATION RESISTANCE
Measure the insulation resistance using a 500 V Megger as per IS 325-1996. The following formula gives a rough estimate of reference value for insulation resistance:
Insulation resistance R ³20xU/ 1000+2P (MOhms.)U = Voltage (V)P = Rated output of the motor (kW)(highest output for a multispeed motor)
0R= Calculated insulation resistance at 25 C
0The formula applies at 25 C ambient temperature. If the temperature is clearly different, the value must be revised with the factor given in the nomogram in Fig. 1
PRE-INSTALLATION CHECKS0Example; at +60 C ambient
temperature the insulation resistance is 0only about 30% of the value at +25 C
Note: Always measure the insulation resistance before the first starting from the beginning of the supply mains to detect possible damages on the cables, wrong connections etc.
Windings should be discharged immediately after measurement to avoid the risk of electric shock.
In case the insulation resistance values are low, then the motor should be dried according to IS 900-1992.
If this value is very low on account of adverse weather conditions or long storage, we recommend that the motor be examined by our local authorised service centre.
Accurate and careful installation of the motor is of prime importance.
Rotating parts such as pulleys, couplings, external fans and shaft extensions should be permanently guardedDisconnect and lock out before working on motor or driven equipment.
The motor should be installed where it can obtain adequate ventilation and clean dry air. The clearance between the fan cover and any barrier should be a minimum of 30 mm upto frame 200.
INSTALLATION & COMMISSIONING
3.0
2.0
1.0
0.5
0.4
0.3
0.2
0.120 40 60 080 C
Fig. 1
2
For higher frames this should be at least 85 mm.
If the air contains dust, moisture or corrosive gases the equipment should be appropriately protected or else supplied with pure air through special pipes or ducting. The motor should be accessible for inspection and repairs.
FOUNDATION & MOUNTING
Foundation must be flat, even, sufficiently rigid and free from vibration. They should be designed as to avoid the occurrence of vibration due to resonance. A cast concrete foundation is therefore recommended. If it is a metal foundation it should be painted to avoid corrosion.
The foundation must be stable enough to withstand the forces that can arise in the event of a three phase short circuit. The short circuit torque is primarily a sinusoidal oscillation, and thus can have both positive and negative values. The stress on the foundation can be calculated with the aid of details in the data tables of the motor catalogue and the formula below :
F=0.5 x g x m + 4 x M /A (N)max
where F = stress per side, N2g = acceleration due to gravity, 9.81m/s
m = weight of motor, kgM = maximum torque, Nmmax
A = Lateral distance between the holes in the motor feet. The dimension is taken from the dimension drawing and is expressed in metres.(Please refer to ABB technical catalogue for values)
The foundation should be dimensioned to give a large enough resonance distance between the natural frequency of the installation and any interference frequency.
Before mounting the motor see that motor feet are cleaned. Foundation studs or a baseplate should be used to secure the motor. Bolt the foundation studs to the feet of the motor firmly. Align the motor directly using appropriate means.
In the case of flange motors, care should be taken to ensure that the motor has a snug fit in the recess and the mounting screws are uniformly tightened.
For foot mounted motors to be fixed on the wall a support should be provided for the mounting feet from below.
DRAIN HOLES
When mounting the motors, make sure that the drain holes face downwards when the mounting designation is different from the standard, See Fig 2. Rotate the endshields so that these holes are no longer between the mounting feet, but at the lowermost point of the motor. In case of vertical mounting, the upper plug must be hammered in completely and grease plug should be positioned in such a way that grease can be applied easily. In very dusty environments or when the motor is in such a position that water can run into the motor both plugs should be hammered home.
MOTOR ALIGNMENT
Correct motor alignment is essential to avoid bearing failures, vibrations and possible fractured shaft extensions. As soon as any vibrations or bearing failures are observed, there is every reason to suspect alignment is faulty and a check therefore to be made.Temperatures have a considerable
3
influence and should therefore be considered during the alignment. The machine temperature is lower during erection than under operating conditions. For this reason shaft centre is going to lie higher during operating conditions. It may be necessary to usecompensating alignment. Mounting instruction from manufacturers of pumps, gear units etc. often state the vertical and lateral displacement of the shaft at operating temperature. It is important to bear in mind this information to avoid the vibration and other problems in service.
FITTING HALF COUPLING/ PULLEY
The driven member(Pulley, Coupling half) must be balanced with a half key. The members should be keywayed and balanced on a smooth shaft. Clean keyway and make sure the key is fitting properly on the sides of the keyway in both shaft and coupling or pulley. The key should have clearance at the top and should not fit tightly on top and bottom faces.
It is recommended that the couplings or pulleys should be heated to a
0temperature of about +125 C in an oil
bath for a sufficient length of time to get uniform temperature and then slid on to the shaft extension of the motor. The coupling half can be locked with an end washer. If the coupling half/pulley is drilled for a tighter than a push fit , it
0must be heated to around 150 C.
Please ensure that, once pressed on members fit tightly. They should be pressed firmly against the shaft shoulder. If the hub of the member is short in relation to the shaft end, the difference in length should be adjusted by placing a distance piece in front of the shaft shoulder. A coupling shaft which is mounted on the shaft with a push fit and is then keyed on can be pushed on by hand along about half the shaft extension. A special tool or a fully threaded bolt, a nut, and a piece of flat iron can be used to press the pulley against the collar of the shaft.
Bearings of the motor will get damaged when a hammer is used to drive the coupling or pulley on to the shaft extension of the motor.Should force be applied to fit the pulley or coupling on shaft, it is desirable that non drive end bearing bracket is removed and shaft is supported so that the hammer or
Fig. 2
4
pressure blows are not borne by the bearings.
Mounting accuracy of a half coupling: check that the clearance b is less than 0.05mm and that the difference a1 to a2 is less than 0.05 mm also. See Fig. no 3.
When investigating whether the shafts are parallel, measure the distance X between the outer edges of the coupling halves at one point on the circumference with a feeler gauge. See Fig 4. Then turn at the same time both
0the coupling halves 90 so that the relative position of the shafts are not altered, and measure again at exactly the same point. The coupling halves
0 0are then turned 180 and 270 and further measurements are made.
The difference between the largest and smallest X-dimension must not exceed 0.05mm(0.002 in) for normally occurring coupling dimensions.
When checking the shafts stand opposite one another, place a straight steel rule parallel with the shafts on the turned circumference of one of the coupling halves then measure the playbetween the rule and the circumference of the other half in four positions as previously. The difference between the highest and lowest value must not exceed 0.05 mm (0.002 in).
The best tools for obtaining a perfect alignment are a couple of dial gauges fitted as shown in Fig. 5. They are placed on each coupling half and point in different directions, one axially and the other radially. By slowly rotating the shafts and reading off at the same time deflections, one can obtain an idea of whether any adjustments should be made in the axial or radial direction. The coupling halves should loosely be bolted together so that they move easily when the shafts are turned.
SLIDE RAILS AND BELT DRIVES
If belt or rope drive is used, install the motor in such a manner that it can be
Fig. 3
Fig. 4
Fig. 5
5
shifted on its base(e.g on slide rails) to obtain correct belt tension. The lower belt part should be pulling. Align so that the centre of the motor's belt pulley is exactly opposite the centre of the corresponding pulley, See Fig 6.
Fasten the motor to the slide rails as shown in the Fig. 7. Place the slide rails
horizontally on the same level. Check that the motor shaft is parallel with driven, or driving shaft. The slide rails should have the screw in opposite directions so that the screw which is nearest the belt is between the motor and the driven machine, See Fig 8. Make certain that the upper surfaces of the slide rails lie horizontally in the
longitudinal direction. The position in the lateral direction determines the driven shaft. After the alignment is completed, grout the foundation bolts and slide-rails with concrete.
V-BELT COUPLING
1. Select proper belts and sheaves, do not over belt. Excessive belt load will damage bearings.
2. Align pulleys carefully to avoid axial thrust on motor bearing. The drive sheave on the motor should be positioned toward the motor so it is as close to the bearing.
3. When adjusting the belt tension, make sure the motor is secured by all mounting bolts before tightening belts.
4. Pulleys that are too small or too wide may damage the bearings or the shaft. Arrange the drive that the slack side of the belt is uppermost. Avoid vertical drives. Fast and loose pulley drives should be arranged such that the drive is on the fastest pulley when the belt is nearest to
Fig. 6
Fig. 7
Fig. 8
6
WARNING
the motor.
5. Adjust belt tension to beltmanufacturers recommendations.Excessive tension will decreasebearing life.
1. Flexible or solid shaft couplingsmust be properly aligned forsatisfactory operation. Use flexibletype couplings which willaccommodate small inaccuracies inalignment between the motor andthe driven member. Ensure that theshaft does not project beyond theface of the coupling and that there isa small amount of axial clearancebetween the faces of the two halvesof the couplings so that the motorbearings are not subjected to endthrust.
2. On flexible couplings, the clearancebetween the ends of the shaftshould be in accordance with thecoupling manufacturer'srecommendations for end play andlimited travel in coupling.
3. Misalignment and Run-Outbetween the direct connected shaftswill cause increased bearing loadsand vibration even when theconnection is made by means of aflexible coupling. Excessivemisalignment will decrease thebearing life. Proper alignment, asper the specification of the couplingbeing used is critical. electricalmachines must always be carefullyaligned, particularly when coupleddirect to a driven machine. Faultyalignment along with bearingfailures cause vibrations andfractured shaft extensions. As soon
DIRECT CONNECTED COUPLING
as any vibrations or bearing failuresare observed, there is every reasonto suspect alignment is faulty and acheck is therefore to be made.
Excessive belt tension willdamage bearings and causeshaft breakage.Do not exceed the maximum beltforces (i.e. radial bearingloading) stated in the relevantproduct catalogues.
Clean the space between the ribs ofthe TEFC motor. Dust can have aharmful effect if it is allowed to settle onthe windings , to enter the bearings, orto collect in the ventilating passagesover a period of time. Therefore motorshould be cleaned with compressedair or blower periodically depending onthe atmospheric conditions on the site.
Be sure rotor turns freely whendisconnected from the load. Any foreignmatter in the air gap must be removed.
If the drive end of the motor facesupward, ensure that the water isprevented from entering the upperbearing.
The cable and air ducts must bearranged so as to facilitate theconnection of the cables.
The maximum level of vibrations asmeasured a per IS 12075-1987 are:
If the machine vibrates even after
VIBRATIONS
.
Max. vibration velocity, mm/s rms as per IS 12075-1987 are:POLE Frame 71-132 Frame 160-225 Above Frame 2252P 1.8 2.8 4.54P-8P 1.8 1.8 2.8
7
WARNING
WARNING
trips. If manual protectors trips disconnect motor from power line. After the protector cools it can be reset and power may be applied to motors.
4. Discharge all capacitors before servicing motor.
5. Never attempt to measure the rise of temperature by touch. Temperature rise must be measured by thermometer, resistance temperature detector, imbedded detector or thermocouple. The temperature of the outlet of the motors may be hot to touch during normal operation.
6. Electrical repair should be performed by trained and qualified personnel only.
7. Failure to follow instruction and safe electrical procedure could result in serious injury or death.
8. If safety guards are required, be sure that guards are in use.
9. Prior to commissioning it is important to check that the incoming cables are separated properly. The cables should be grounded.
TERMINAL BOX
Beside the main winding and earthing terminals the terminal box can also contain connections for thermistors, space heaters or PT 100 resistance elements.Before closing the terminal box ensure
8
proper alignment on an amply sized foundation, this could be caused by incorrectly balanced pulley, coupling shaft or similar, fitted to the shaft. Other causes could be a weak foundation structure generating vibrations.
Fuses alone do not protect a motor against single phasing or overloading. Fuses protects the supply lead but not the motor. Use a reliable starter with proper protection devices to protect the motor against faulty operating conditions. We recommend the use of over load setting, under voltage relay, single phasing preventer , motor protection relays.
1. Disconnect power before working on motor or driven equipment. It is necessary to make sure that rotor of the motor can neither be energised electrically nor start to rotate by any other means.
2. Motors with automatic thermal protectors will automatically restart when the protector temperature drops sufficiently. Do not use motors with automatic thermal protectors in applications where automatic restart will be hazardous to personnel or equipment.
3. Motor with manual thermal protectors may start unexpectedly after protector
MOTOR PROTECTION
ELECTRICAL CONNECTION
that:- Interior of the terminal box is clean
and free of cable residue.- All terminals and screws and bolts
are firmly tightened.- All sealing surfaces have adequate
contact.- Unused cable entries must be
closed.
EARTHING
Clean the area underneath the earthing terminal and smear it with petroleum jelly before making earthing connections. Two separate earthing screws (painted green) are provided for earthing. Connect the protective earth conductor to the terminal located in the terminal box, and on the motor body.
DIRECTION OF ROTATION
As standard, the motors are connected in a clockwise rotation as determined from the drive end. In the case of motors designed for operation in one direction only the direction of rotation is indicated by an arrow plate, See Fig 9.
Changing rotation : Before the motor is coupled to the load, determine proper rotation by jogging or bumping. Apply
power to the motor for a short period of time, enough to get the motor shaft to rotate a slight amount to observe the shaft rotating direction. To reverse the rotation interchange any two of the three line leads.
REDUCED VOLTAGE STARTING
Motors used on reduced voltage starting, should be carefully selected on power supply limitations and driven load requirements. The motor's starting torque will be reduced when using reduced voltage starting. The eclipsed time on the start step should be kept as short as possible.
VOLTAGE AND FREQUENCY VARIATION
If voltage and frequency are within the following range, motors will operate, but with somewhat different characteristics than obtained with correct name plate values.
Voltage: 10% of the value stamped on the name plate. 3 Phase systems should be balanced within 2%. A small voltage imbalance will cause a significant current imbalance. Please see that the full load current does not exceed the name plate current and is balanced in all three phases.
Frequency: 5% of the value stamped on the name plate.
Voltage and frequency together: Within 10%(providing frequency variation is less than 5%) above or below values stamped on the name plate.
CONNECTIONS
Connect the motor terminals as per connection diagram provided at the
9
fig. 9
fig. 10Y Connection
Connection
CAUTION
terminal box cover.
The terminal plate is normally equipped with 6/3 terminals.In direct starting the motor can be used in two different
connections as in Fig.10. In the event that a star-delta starter is used no links are required on the terminal plate, and all 6 terminals are connected to the corresponding terminals of the starter.
PRECAUTIONS
The supply cables should be of adequate size to carry the full load current(current density not greater than
24 Amp/mm ) and also large enough to carry the starting current without excessive voltage drop. The starting current for DOL starting will be 6 to 7 times full load current at rated voltage in case of squirrel cage motors.
Use proper size of line current protection and motor controls as required by Indian Electricity Rule. Recommended use is 115% of full load
0amps at 40 C and a service factor of 1.0. Do not use protection with larger capacities than recommended. Three
phase motors must have all three phases protected.
Space heater(if provided) should be switched ON when the motor is not running and OFF before starting the motor.
Leave the motor disconnected from the load for the initial start; it is desirable to operate the motor without load for about an hour to test for any localised heating in bearings and windings.
Check for correct and balanced voltage and current at the motor terminals.
T TIMEhot
T time by definition is the permissible hot
time for a motor with rotor in locked condition. For the setting of certain electronic relays, T times are required. hot
This is available from the T times in hot
ABB technical catalogue.
Too many starts and over-loading of the motor will overheat the windings and reduce the life of the insulation.
When a squirrel cage motor is used with an inverter the following must be done.
1. Always check :a. The motor and inverter ratingb. Insulation level of motor c. Earth connection of motor and the
driven equipment
OPERATION WITH INVERTERS
10
2. Check if the motor will be operating at high speeds:a. Bearing type and lubricationb. Fan characteristicsc. Critical speedsd. Maximum torque
3. Check if the motor will be operating at low speedsa. Bearing type and lubricationb. Motor's cooling systemc. Magnetic noise
CLEANING
Inspect the motor at regular intervals. Keep the exterior and interior of the motor free from dust , oil and moisture. Dust can have a very harmful effect. Motor should be blown out periodically depending on the atmospheric conditions of the site. Make sure there is free ventilation air flow. Use safe solvent(e.g. Carbon tetra chloride- CTC) to remove any gummy accumulations of dirt in air passages.
Winding
Keep clean to prevent layer of dust from acting as a heat insulator, holding moisture or chemical particles or from starting abrasive action on insulation. Inspection is required regularly, depending on conditions around the motor. Open motors in dusty locations should be avoided. To clean windings, vacuum clean or blow out with air. Clean gummy dirt with a safe solvent(e.g. white petroleum, lactra clean). Revarnish coils if varnish has got removed.
MAINTENANCE
CHECKS
Insulation resistance should be checked regularly between phases and phase to earth terminals.
- Inspect earthing terminals and clean regularly.
- Check the condition of shaft oil seals and replace if necessary.
- Check the condition of connections and mounting and assembly bolts.
DRYING MOTOR
Motors installed outside or in a humid environment can be fitted with space heaters to prevent the insulation resistance dropping during idle periods. An element rated 50/100 W provides enough heat for a motor upto 355 frame. In small low-voltage squirrel cage motors the stator winding can be used to heat the motor when it is idle. For this, a single-phase voltage of about 10% of the rated voltage of the motor is connected to two of the terminals for a small duration.
RE-ASSEMBLY
The motors must be assembled in a dust free, dry and clean location. Provide a fresh coat of bearing grease to all the machined mating surfaces for motors with IP55 protection. Unmachined surfaces should have rubber gaskets in good condition mounted carefully to achieve correct sealing. During reassembly all fasteners that are used on the exterior of the motor are provided with a coat of suitable loctite sealant available in the market, to prevent ingress of water and dust through tapped holes.
11
When assembling the shaft oil seal ensure that they are fitted properly.
(For other maintenance tips refer to our troubleshooting chart)
FANS
The axial locking of thermoplastic fans is provided with built-in tounges which engage in the groove of the shaft. Thermoplastic fans have two openings for the insertion of puller arms so that the pulling force can directly act on the fan-hub.
For removal of fans only a proper puller is to be used. Hammering is strictly not permitted since the same can damage fans. In case of fans with built in tounges for axial locking, the same should temporarily held in lifted up position at the time of removal.
Metallic fans are axially locked with separate circlip. These fans are best removed by engaging the puller arms on the outer rim of the fan. In case of the larger fans the tapped holes provided on the hub can be used.
BEARING MOUNTING
When a bearing is mounted on a shaft, cold or hot mounting may be used. Cold mounting is only suitable for small bearings . For hot mounting, the bearing is heated in an oil bath or with a special heater or with an induction heater. It is then pressed on to the shaft with a mounting sleeve that fits the inner ring of the bearing or with the help of other specialised tools for the purpose. Grease-filled bearing which usually have sealing plates or shield
BEARINGS
plates, should not be heated.
BEARING REMOVAL
In many instances bearings have to be removed . Regrettably it often happens that bearings that are perfect before removal for inspection or cleaning are damaged during removal or mounting. It is good practise only to remove bearings when strictly necessary. Instead of removal bearing inspections must be done by checking for unusual noise, scoring marks, vibration measurement, bearing temperature (see Fig. 11), inspection of spent grease( for any change in colour), grease leakage and SPM monitoring.Removal of small and medium sized bearings does not present any difficulty. They are usually removed by using conventional pullers. Reusable bearings having interference fit on the shaft have to be removed by attaching the puller jaws to the inner ring of the bearing. If it is necessary to attach
puller arms on the outer ring of the bearing, then the bearing must be rotated during withdrawal to avoid damage to the bearing. When bearings are removed from the motor wrap them in a polythene with grease immediately, if partially dismantled, keep them free from dirt/corrosive atmosphere. The removal of large bearings is more complicated. For example they can be
Fig. 11
12
removed cold with the aid of hydraulic pullers. It is a good idea to get expert advice before attempting the removal of large bearings.
Bearings that have been removed should be reused only if they show no signs of damage and provided they are thoroughly cleaned beforehand. For cleaning bearings use proper cleaning agent e.g. white spirit or CTC, and wear gloves for protection. The cleaned bearing must be free from foreign bodies.
Removal of bearings or inner rings which are not to be re-used is facilitated by heating them with gas or welding torch.
Motors provided with Roller bearings on the drive End side have very high dynamic capacity. As per bearing manufacturers the roller bearing performs satisfactorily only when it is physically loaded to approximately 1-2% of its dynamic capacity. In view of this , the roller bearing may not run smooth when the motor is run uncoupled.
It is advisable not to run the motor with roller bearings in uncoupled condition.
By far the commonest type of fault to affect electric motors is bearing damage. Experts estimate that although more secure bearing housings and more reliable high capacity bearings have been introduced, bearing defects still account for around three quarters of all motor faults.The main reasons for bearing failure
FOR INFORMATION:
are poor alignment of the motor and driving machine, badly balanced coupling, vibrating or weak foundations and the like. Faults of this type give rise to pulsating forces which reach the bearing valve shaft and can cause the bearing to wander. This means that the outer ring of the bearing starts to rotate in it's seating, leading to failure.
When a belt pulley or coupling is being fitted and, unfortunately, also when the bearings are being changed, it often happens that a hammer or tin sledge is used. This results in indentations in the bearing races. These relatively small marks are enlarged during the rotation of the bearing and will result eventually in severe flaking. The danger of such handling of bearing cannot be sufficiently over-emphasised.Among other reasons for bearing failure is overtensioning of the belts, which damages bearings and may even lead to shaft fracture, and failure to observe the lubrication instructions for the motor and duty in question, which may lead to bearing running dry and failing.
There are now objective methods for monitoring condition of ball and roller bearings based on the techniques of condition monitoring at regular intervals or vibration analysis. These methods allow the life reserve of bearings to be better utilised and replacements to be planned in good time.
13
LUBRICATION
GREASE VALVE LUBRICATION
The motors are provided with single-row deep groove ball bearings on both ends.The complete type designation of each bearing is stamped on the motor rating plate, including bearing sizes and radial clearance class. The lubrication used in the bearings is Lithium complex grease (IOC Servoplex LC3 or equivalent)
The principle of valve lubrication is that while the motor is running the grease is forced in behind the bearing and so through it, See Fig 12. The old grease is forced out through the gap on a rotating disk which carries the excess grease out through an opening in the outer bearing cover. The grease that
remain in the outlet opening serves as a seal against the entry of dust. The advantages of grease valve lubrication is that the grease can be changed with the motor in service, and that the
bearing can never be over lubricated. A plate stating the lubrication intervals is attached to every motor with grease valve lubrication. It is important to follows these instructions . The stated intervals are for a motor installed in a normal environment. If the place is particularly dusty or wet the intervals should be shorter.
Relubrication procedure:
- Remove grease outlet plug if fitted.
- Press fresh grease into the bearing until all old grease has been forced out.
- Let the motor run 1-2 hours to ensure that all excess grease is forced out of the bearing. Close the grease outlet plug if fitted.
Regrease motors while running. If this is not possible, lubrication can be carried out while the machine is at a standstill. In this case, use only half the quantity of grease, then run the motor for a few minutes at full speed. When the motor has stopped, the remaining quantity of grease can be forced in until the old grease has been replaced. After 1-2 running hours close the grease outlet plug (If fitted).
The grease outlet plug must be removed permanently with automatic lubrication.
If the machine is fitted with a lubrication information plate, follow the values given, otherwise use the valves in table below.
Fig. 12
14
FRAMES
HX 71
HX 80
HX 90 SL
HX100 L
HX 112 MA
HX132 SM
HX160 ML
HX180 ML
HX200 ML
HX225 SM
HX250 M
HX280 SM
M2BA315 SM ML 2P
M2BA315 SM ML 4...8P
M2BA355 SM ML 2P
M2BA355 SM ML 4...8P
BEARING
DS NDS
6203ZZ 6202ZZ
6204ZZ 6203ZZ
6205ZZ C3 6205ZZ C3
6306ZZ C3 6206ZZ C3
6307ZZ C3 6206ZZ C3
6308ZZ C3 6307ZZ C3
6309ZZ C3 6308ZZ C3
6310 C3 6309 C3
6312 C3 6311 C3
6313 C3 6312 C3
6315 C3 6313 C3
6316 C3 6315 C3
6316 C3 6316 C3
6319 C3 6316 C3
6319 C3 6319 C3
6322 C3 6319 C3
GREASE RELUBRICATION
QTY. INTERVAL (HRS)
GM DS NDS
- - - -
- - - -
- -
- - - -
- - - -
- - - -
- - - -
15 12 4200 (2P) 4400 (2P)
7000 (4P) 7300 (4P)
9000 (6P) 9300 (6P)
10700 (8P) 11000 (8P)
20 17 3600 (2P) 4000 (2P)
6700 (4P) 6900 (4P)
8700 (6P) 8900 (6P)
10300 (8P) 10500 (8P)
23 20 3200 (2P) 3600 (2P)
6500 (4P) 6700 (4P)
8500 (6P) 8700 (6P)
8500 (8P) 8700 (8P)
30 23 2400 (2P) 3200 (2P)
6100 (4P) 6500 (4P)
8100(6P/8P) 8500 (6P/8P)
35 30 2000 (2P) 2400 (2P)
6000 (4P) 6100 (4P)
8000 (6P) 8100 (6P)
15100 (8P) 15300 (8P)
35 35 1000 (2P) 1000 (2P)
45 35 3000 (4P) 3500 (4P)
2500 (6P) 6000 (6P)
2500 (8P) 6000 (8P)
45 45 800 (2P) 800 (2P)
60 45 2200 (4P) 5000 (4P)
2500 (6P) 5000 (6P)
4000(8P) 5000 (8P)
RELUBRICATION CHART
15
TROUBLE
Motor fails to start
The above table is prepared for horizontally mounted motors. Lubrication intervals for vertical motors are about half of the above values.
The grease amount in the table is used if small quantities of fresh grease are replaced at regular intervals as above.
As an alternative, when the machine is provided with grease escape valves, fresh grease may be pressed into the bearings until the old grease is totally replaced.
High speed operation i.e. inverter applications, or lower speed with heavy loading will require shortened lubrication intervals.
Typically a doubling of speed will require reduction of lubrication intervals to approx. 50% of values in the table.
CAUSE
Blown fuses
Overload trips
Improper power supply
Improper line connection
Open circuit in winding or control switch
Mechanical failure
WHAT TO DO
Replace fuses with proper type and ratings.
Check and reset overload in starter.
Check to see that power supply agrees with motor name plate and load factors.
Check connections with diagram supplied with motor.
Indicated by humming sound when switch is closed. Check for loose wiring connections. Also, ensure that all control contacts are closing.
Check to see if motor and drive turn freely. Check bearings and lubrication.
TROUBLE SHOOTING CHART
16
Short circuited stator
Poor stator coil connection
Rotor defective
Motors may be over loaded
One phase may be open
Wrong application
Overload
Low voltage
Open circuit
Power failure
Not applied properly
Voltage too low at motor terminals because of line drop
Starting load too high
Broken rotor bars or loose rotor.
Indicated by blown fuses. Motor must be rewound.
Remove end shields, locate with test lamps
Look for broken bars and/or end rings
Reduce load.
Check lines for open phase.
Change type or size. Consult manufacturer.
Reduce load.
Ensure the name plate voltage is maintained. Check connection.
Fuses blown, check overload relay, stator and push buttons.
Check for loose connections to line, fuses and control.
Consult supplier for proper type.
Use higher voltage or transformer terminals or reduce load. Check connections. Check conductors for proper size.
Check load motor is supposed to carry at start.
Look for cracks near the rings. A new rotor may be required, as repairs are
Motor stalls
Motors runs and then dies down
Motor does not come up to speed
17
Open primary circuit.
Excessive load
Low voltage during start
Defective squirrel cage rotor
Applied voltage too low
Wrong sequence of phases
Overload
Frame vents may be clogged with dirt and prevent proper ventilation of motor
Motor may have one phase open
Grounded coil
Unbalanced terminal voltage
Motor misaligned
Weak support
Coupling out of balance
Driven equipment unbalanced
usually temporary.
Locate fault with testing device and repair.
Reduce load
Check for high resistance. Adequate wire size.
Replace with new rotor.
Increase power tap.
Reverse connections at motor or at switchboard.
Reduce load.
Open vent holes and check for a continuous stream of air from the motor.
Check to make sure that all leads are well connected.
Locate and repair.
Check for faulty leads, connections and transformers.
Realign.
Strengthen base.
Balance coupling.
Rebalance driven equipment.
Motor takes too long to accelerate and/or draws high amp
Wrong rotation
Motor overheats while running underloaded
Motor vibrates
18
Defective bearings
Bearings not in line
Balancing weights shifted
Contradiction between balancing of rotor and coupling(half key - full key)
Polyphase motor running single phase.
Excessive end play
Fan rubbing fan cover
Fan striking insulation
Loose on bedplate
Rotor unbalance
Bent or sprung shaft
Excessive belt pull
Pulleys too far away
Pulley diameter too small
Misalignment
Insufficient grease
Deterioration of grease of lubricant contaminated
Replace bearings.
Line up properly.
Rebalance motor.
Rebalance coupling or motor.
Check for open circuit.
Adjust bearing or add shim.
Remove interference.
Clear fan.
Tighten holding bolts.
Rebalance.
Straighten shaft.
Decrease belt tension.
Move pulley closer to motor bearing.
Use larger pulleys.
Correct by realignment of drive.
Maintain proper quality of grease in bearing.
Remove old grease, wash bearings thoroughly in kerosene and replace with new grease.
Scraping noise
Noisy operation
Hot bearings general
Hot bearings ball
19
Excess lubricant
Overload bearing
Broken ball or rough races
Reduce quantity of grease, bearing should not be more than 1/2 filled.
Check alignment, side and end thrust.
Replace bearing, first clean housing thoroughly.
20
RVM
CAD
RVM
CAD
1
2
3
4
6
8
14
13
15
16
17
19
5
12
18
7
11
10
9
20
21
22
23
1
B
ea
ring
Co
ver D
S O
ute
r
2
E
nd
shie
ld D
S
3
B
ea
ring
DS
4
B
ea
ring
co
ver D
S in
ne
r
5
S
ha
ft e
xte
nsi
on k
ey
6
R
oto
r a
sse
mb
ly
7
F
an k
ey
8
W
ound
sta
tor
9
T
erm
ina
l bo
x
10
Te
rmin
al p
late
11
Te
rmin
al b
ox
co
ver
12
Eye
bo
lt
17
Fan
18
Circ
lip
19
Fa
n C
ow
ling
13
Be
arin
g N
DS
14
Be
arin
g C
ove
r N
DS
Inne
r
15
End
shie
ld N
DS.
16
Be
arin
g C
ove
r N
DS
Oute
r
20
21
22
23
Gre
ase
Outle
t Plu
g
Re
gre
asi
ng
Ho
le
Dra
in H
ole
Plu
g
Ea
rthin
g B
olt
Ex
plo
de
d v
iew
of
HX
mo
tor