GEH-5304A GE Industrial Systems Instructions Direct Current Motors & Generators Type CD Frames 2512AT, 2513AT Frames 2812AT, 2813AT
GEH-5304A These instructions do not purport to cover all of the details or variations in equipment nor to provide for every possible contingency to be met in connection with installation, operation, or maintenance. Should further information be desired or should particular problems arise which are not covered sufficiently for the purchaser’s purposes, the matter should be referred to the General Electric Company.
GEH-5304A Table of Contents Subject Page Introduction..............................................................................................................................5 Receiving ..................................................................................................................................5 Storage ............................................................................................................................5 Handling ...........................................
GEH-5304A Subject Page Brushes .......................................................................................................................... 22 Brush Removal With Machines Stopped and Power Off......................................... 22 Brush Installation................................................................................................... 23 Commutator...................................................................................................................
GEH-5304A Direct Current Motors and Generators Type CD Frames 2512AT, 2513AT, 2812AT, 2813AT I. INTRODUCTION This instruction book covers the CD2512AT-CD2813AT line of DC motors and generators. High voltage and rotating parts can cause serious or fatal injury. The use of electric machinery, like all other utilization of concentrated power and rotating equipment, can be hazardous. Installation, operation and maintenance of electric machinery should be performed by qualified personnel.
GEH-5304A Brushes should not remain in contact with the commutator during prolonged storage because corrosion may occur and later result in flat spots on the commutator. Release the brush springs and lift the brushes when stored for a period of more than six months. All exposed machined steel parts are slushed with a rust preventative before shipment. These surfaces should be examined carefully for signs of rust and moisture, and reslushed if necessary.
GEH-5304A Table 1 Typical Weights** CD2512AT CD2513AT CD2812AT CD2813AT Motor (Less Accessories) 500 550 650 750 Armature 120 135 160 190 **Typical weights. For specific weight, see certified outline. III. INSTALLATION Installation should be in accordance with the National Electrical Code and consistent with all local codes. Coupling, belt and chain guards should be installed as needed to protect against accidental contact with moving parts.
GEH-5304A B. Mounting Motors and generators should be mounted on rigid and solid foundations. Level the base (or the machine). Hold-down bolts should be inspected regularly and kept tight. The feet of the machine may be doweled to the foundation plates or base when alignment procedures are completed. Sliding bases, when used, should be securely anchored to the foundation. Motors are mechanically suitable for mounting with shaft horizontal or vertical on floor, ceiling or sidewall.
GEH-5304A Horizontal alignment should be corrected by shifting machines on the base. b. Alignment Procedure Flexible Couplings, Self-Supporting Bases Before operating the machine, the base should be bolted down and the alignment checked as follows: 2. 1. Remove all of the coupling bolts and slide the shells back so that the hub faces are exposed. 2. Check the coupling hub spacing in accordance with the outline dimensions with the units in the mechanical center of their end play. 3.
GEH-5304A The radial load, W, produced by the belts when tightened just enough to transmit the load without slipping is given by the relation: 126,000 x HP W x Kb, lbs = D x RPM Where: D = Sheave pitch diameter in inches for V-belt application HP RPM = Maximum ratio of horsepower, including overloads, to the minimum speed at which that power occurs. Kb = Belt tension factory from table below: Kb 1.0 1.2 1.5 1.8 2.
GEH-5304A Mounting may be either horizontal or vertical for these bearing life determinations, as long as no axial load (i.e., suspended load) other than the weight of the armature is present if vertical. 5. Special Load Considerations Where the load is overhung beyond the motor shaft extension or greater bearing life is desired, the application should be referred to GE Industrial Systems. 6.
GEH-5304A Before starting the motor, remove all unused shaft keys and loose rotating parts to prevent them from flying off. A. Inspection Before Starting These inspection procedures should be followed before starting the machine for the first time, after an extended shutdown or after a teardown for extensive maintenance or repair. 1.
GEH-5304A Table 3 Bearing Life at 1750 RPM Average Speed Vs. Load, W (For other average speeds, multiply life by life factor) Speed Life Factor Less Than 500 2.15 650 1.83 850 1.55 1150 1.29 1500 1.10 2000 .92 2500 .80 3000 .72 4000 .60 5000 .
GEH-5304A NP Rating Code Table 4 Power Supply Available A C D E K A √ √ √ √ √ C * √ √ √ √ D * * √ √ √ E * * * √ √ K * * * * √ √ Compatible power supply. * External inductance may be necessary to limit ripple current. C. Power Supply Identification The nameplates of DC motors intended for operation from rectified power supplies will be stamped with a power supply identification as described below. 1.
GEH-5304A 2. When intended for use on a power supply other than “A”, “C”, “D”, “E” or “K”, the motor will be identified as follows: M/NF - V - H -L Where D.
GEH-5304A Thermostats automatically reset after the motor has cooled somewhat. In order to prevent property damage or injury to personnel, the control circuit should be designed to prevent re-energizing of the motor when the thermostat resets. Table 5 Maximum Current Ratings for Thermostats on Dripproof and Totally Enclosed Motors (Normally open or normally closed contacts) Load 125 VAC 250 VAC 600 VAC 30 VDC Do not use above 600 VAC or 30 VDC Resistive 5 Amps 2.5 Amps 1 Amp 5 Amps Inductive* 3 Amps 1.
GEH-5304A The surface of a space heater block becomes hot when the heater is energized. The temperature rise above the ambient temperature may be as high as 400°C. Avoid touching heater blocks which have recently been energized to prevent burns. Also, to prevent fire or explosion, ignitable dust or lint should not be allowed to collect around the surface of the heaters. J. Ventilation System Blowers or central systems must be in operation to supply cooling air before loading force ventilated machines.
GEH-5304A Table 7 Bolt Tightening Torque Values Thread Sizes (UNC-2A) 1/4-20 5/16-18 3/8-16 1/2-13 5/8-11 3/4-10 Hex Head (C1C5) Grade 5 Medium Carbon Steel (Without Lubricant) Lb-Ft N-m 7-9 10-12 13-17 18-23 24-30 33-40 60-75 80-100 120-150 160-200 210-260 280-350 For lubricated bolts, use 65% of value shown in Table 7. L. Accessory Mounting Provisions for mounting accessories on the commutator endshield is a standard feature.
GEH-5304A 2. Noise and Vibration Check for unusual vibration or noises that might indicate rubbing or interference. Vibration of new machines at the bearing housings, as measured by a vibration meter, should not exceed the values shown in Table 8. (Measurements are according to NEMA MG 1-12.06 and MG 112.07.) The most likely cause of vibration in new machines is misalignment due to improper installation, loose foot bolts, uneven shimming under feet, or damage to machine during shipment or installation.
GEH-5304A A. Disassembly The following procedure should be used for disassembly: B. 1. Remove all covers. 2. Disengage brush springs. 3. Remove complete brushholder assemblies. 4. Remove four (4) nuts on CE bracket. 5. Remove commutator end cover plate, if fitted. 6. Remove four (4) CE bearing cap bolts. 7. Using a soft mallet, tap on CE bracket to remove it. 8. Remove four (4) DE bearing cap bolts. 9.
GEH-5304A C. Bearings Ball bearing and roller bearing housings are packed with grease at the factory. Therefore, greasing is not required before the motor is put into service. Since the oil in the grease will ultimately become depleted, it is necessary to relubricate ball bearing and roller bearing motors periodically, depending on the size and type of service (refer to Table 9). Avoid mixing different kinds of grease. Lubricate the motor at standstill.
GEH-5304A Table 11 Sources of Supply for Bearing Greases Temperature Standard Temperature 15°F to 212°F -10°C to 100°C GE Designation D6A2C5 Supplier Supplier’s Designation GE Supply 158 Gaither Drive Mt. Laurel NJ 08054 1-800-341-1010 GE Ball Bearing Grease (supplied in In small tubes and cans) Shell Oil Company P.O. Box 2463 One Shell Plaza Houston TX 77002 (713) 241-4201 Alvania No. 2 Texaco, Inc.
GEH-5304A 2. a. Unfasten pigtail. b. Release spring by pushing in slightly to disengage locking tab, then pull spring back. c. Remove brush. Brush Installation The following procedure should be used to install brushes: a. Place brush in holder with bevel towards spring. Brushes should move freely in holder. b. Push spring into position until lock tab engages slot and locks. c. Connect pigtail.
GEH-5304A Do not use liquid solvents of any kind. Solvents will not remove carbon dust accumulations, but will spread and wash them into critical areas. Figure 2 Brush Assembly F. Commutator Keep the commutator clean. Ordinarily, the commutator will require only occasional wiping with a piece of canvas or other nonlinting cloth. Do not use lubricant or solvent on the commutator.
GEH-5304A G. Mechanical Check the condition of air filters and replace filters if they are dirty. Check for unusual noises which were not present when the unit was originally installed. Check all electrical connections for tightness. Clean out any dirt from screens, louvers, etc. which would interfere with the flow of cooling air. H. Shaft End Play The CD2512AT-CD2813AT designs use a wavy washer (preload spring) to eliminate endplay. I.
GEH-5304A ues.
GEH-5304A For maximum insulation life, these three causes of insulation failures should be prevented: L. 1. Contamination. 2. Mechanical factors. 3. High temperatures. Testing Methods 1. Visual Inspection In addition to collecting contaminants, insulation shrinks, cracks and becomes brittle with heat and age. These changes allow movement of coils, loose filler strips, loose ties, chafing and abrasion, all of which can be picked up by visual inspection.
GEH-5304A Table 13 Effect of Temperature on Insulation Resistance Winding Temperature (Degree C) 80 70 60 50 40 30 20 10 Multiplying Factor to Obtain Insulation Resistance at 40°C (104°F) 10.00 5.50 3.10 1.70 1.00 0.55 0.31 0.17 Note that for a 104°F (40°C) decrease in temperature, the insulation resistance is increased by a multiplier of ten. The insulation resistance of a machine is affected by its design.
GEH-5304A Dirt can be removed from stationary parts of the machine by either compressed air or a vacuum nozzle or a combination of both. Air should be directed between the stator coils, into the pocket corners of bearing brackets, around the cables and onto the brush rigging. Special care should be taken to keep the commutator clean. The commutator should be wiped with a clean lint-free cloth after blowing out.
GEH-5304A FREON TF is a chlorofluorocarbon. Chlorofluorocarbons have been identified as upper atmosphere ozone depletors. The use of Freon in industry is expected to be greatly reduced in the future. The availability of Freon may be limited, and its use could be prohibited by regulations. Carbon brush performance may be ruined by absorbed solvents. brushes prior to solvent wiping. N. Remove Drying of Windings Drying of machines is most effectively done by application of heat.
GEH-5304A An extreme overload or electrical failure may result in heating or arcing, which can cause the insulation to give off noxious fumes. All power should be removed from the motor circuit as a precaution, even though the circuit has overload protection. Personnel should not approach the motor until adequate ventilation of the area has purged the air of fumes. When covers of a totally enclosed motor are removed after a failure, care should be observed to avoid breathing fumes from inside the motor.
GEH-5304A Table 14 Recommended Spare Parts Number of Duplicate Motors in Service Description 1 With or Without Electrical Shop Facilities Complete Machine --Ball Bearing (Sets) 1 Brushes (Sets) 2 Brushholders (Sets) --Brushholder Springs (Sets) 1/2 Armature (Complete) * --Wound Frame ** --Blower Ventilated Motors: Blower Motors --With Electrical Shop Facilities: Shaft --Armature Rewinding Supplies --* 2-4 5-10 10-20 More Than 20 --1 4 1/2 1 1 --- --1 6 1/2 1 1 1 1 2 8 1 2 2 2 2 3 10 1 2 2 2 1 1
GEH-5304A Commutator Check Chart For Comparing Commutator Surface Markings SATISFACTORY COMMUTATOR SURFACES LIGHT TAN FILM over entire commutator surface is one of many normal conditions often seen on a wellfunctioning machine- MOTTLED SURFACE with random film pattern is probably the most frequently observed condition of commutators in industry. SLOT BAR-MARKING, a slightly darker film appears on bars in a definite pattern related to number of conductors per slot.
GEH-5304A Figure 3 Application Information for CD2512AT – CD2813AT Frames 34
GEH-5304A Figure 4 Blower Unit, Commutator End Mounted for Use With CD2512AT – CD2813AT Frames 35
GEH-5304A Figure 5 Dimensions, Air Openings for CD2512AT – CD2813AT Frames 36
GEH-5304A Table 15 Air Flow Requirements For Separately Ventilated Motors Frame 2512AT, 2513AT 2812AT, 2813AT Base Speed RPM All All CFM 380 455 Static Pressure Inches of Water A B Standard Enclosed Separately Separately Ventilated Ventilated 4.85 6.1 4.8 5.64 A. Standard Separately Ventilated Air in one CE opening with solid covers on other CE openings. Standard louvered covers on DE air outlets. B.
GEH-5304A Figure 6 Accessory Mounting CD2512AT – CD2813AT 38
GEH-5304A Figure 7 Accessory Mounting CD2512AT – CD2813AT 39
GEH-5304A 40
GEH-5304A Type CD Frames 2512AT – 2813AT DC Motors & Generators Figure 8 Type CD Frames 2512AT – 2813AT 41
GEH-5304A To: GE Industrial Systems Attn: Industrial Engineering Technical Publications Editor 2000 Taylor Street Fort Wayne IN 46801-2205 Fax: 1-219-439-3881 (GE Internal DC: 8*380-3881) 5HDGHU &RPPHQWV General Electric Company We welcome comments and suggestions to make this publication more useful. Your Name Today’s Date If needed, how can we contact you? Your Company’s Name and Address Job Site Fax No. GE Requisition No. Phone No. Publication No.
GEH-5304A Detach and fax or mail to the address noted above.
GEH-5304A ……………………………………………….…………………Fold here and close with staple or tape………………………………….…………………. Place Stamp Here GE INDUSTRIAL SYSTEMS INDUSTRIAL ENGINEERING TECHNICAL PUBLICATIONS EDITOR 2000 TAYLOR STREET FORT WAYNE IN 46801-2205 USA …………………………………………………..………….………………..Fold here first……………………………………………………………….
GEH-5304A Document Revision History Rev # 0 Date 12/14/99 Author GJG ISAAC # N/A Description Conversion from PageMaker.