Marathon MX Series Generators Information and Installation

General information about Marathon MX Series AC three phase brushless generator. The service manual also suits to marine generator (MX generator).

First of all, please read the service manual before using the generator.

① Safety Caution

PLEASE REMEMBER SAFETY FIRST. If you are not sure of the instructions or procedures, seek qualified help before continuing. This service manual emphasizes the safety precautions necessary during the installation, operation and maintenance of the MAGNAMAXDVR~ generator.

1.The lifting eyes on the generator are designed to support the generator only. Don't lift a complete generator set by means of the lifting eyes on the generator, Personal injury or damages to the equipment may result.

2. Don't apply any force to the generator fan. Never "BAR OVER" the generator set by using the fan. Failure to comply with these safety procedures could result in severe injury to personal or damages to the equipment.

3.Before any service work is done, disconnect all power sources, and lock out all controls to prevent an unexpected start-up of the generator set.

4.Proper grounding in compliance with local and national electrical codes must be provided.

5.Whenever the generator is running, always assume and proceed as if voltage is present. Residual voltage is present at the generator leads and at the regulator panel connections, even with the regulator fuse removed. Caution must be observed. Otherwise, serious personal injury or death can result.

6.Whenever solvents, cleaners, or flammable liquids are present, adequate ventilation must be available to avoid fire, explosion, and health hazards. Always avoid breathing vapors and use suitable personal protective equipment to prevent personal injuries (such as eyes, face, and hand protection).

7. Special caution must be taken during trouble shooting since protective covers and safety devices may be removed or disabled to gain access and make tests.

② Description

MX series three phase AC synchronous brushless generator is a new generation brushless generator, which based on the MAGNA MAX~DVR generator of Marathon electric co., USA. It offers the PMG exciting system and the original digital voltage regulator ( BE2000E), so it is new product integrating traditional generator and the modern state of art.

MX generator can be combined with different kinds of diesel engine (internal combustion engine) to make fixed or movable electrical power. It is suited for commercial buildings, hospitals, factories, farms, fields, etc. as power and lighting. The generator set can be used as prime or standby power. A special power supply also can be constructed if in cooperated with other prime-mover. Because of small size, light weight and easy operation, this kind of generators have been used in varying condition.

MX series generators are of unique design, advanced construction, excellent performances and

reliably using, it is especially suited for the system where all and part of the load is non-linear, and these outstanding features make it the first ideal generator for computers, telecommunication centers, commercial buildings, hospitals, airport, etc, important field.

Features:

1. MX series generators are manufactured in accordance with NEMA ODP types, of which consists main generator, AC brushless exciter, rotating rectifier, PMG, voltage regulator, conduit box, etc.

2. he frame is made of steel plate, and the bracket and adapter are made by high grade iron cast. The adapter and drive discs of single bearing generators are conformity with SAE standard.

3. The design of stator lamination is unique. If necessary, the generator with 6 or 12 leads can be supplied.

4. Main rotor adopts the single piece 4-pole salient pole lamination, coupled with aluminum die cast or welding damping winding to form a unirotor construction. The field winding is directly layer wound with thermo setting epoxy for high mechanical and electrical integrity.

5. The BE2000E is an electronic, solid-state, microprocessor-based control device. Input power to the BE2000E is from a multi-pole, high-frequency permanent magnet generator (PMG). It consists of three phase pure-RMS sensing, various operation and protection function. It is full encapsulated, and has the ability to against moisture, vibration, shock, etc. harsh condition. The regulator meets EMI suppression to Mil-Std-461C, part 9. (See the regulator manual for more information).

6.PMG supplies power to the  BE2000E  . It isolates the power of the regulator from the load, so as to be free from the effect of waveform distortion of load voltage and the fluctuation of voltage. PMG and DVR exciting system improved the ability of nonlinear load, dynamic function and starting-up motor.

Performance:

1. MX series generator can be operated continuously at rated load under following conditions:

 a. Ambient temperature，air≤40'C, good ventilation; marine≤45℃

 b. Altitude≤l000m over sea level

2. Electrical performance:

 a.Steady voltage regulation≤0.5%

 b.Transient voltage regulation≤+20%, -15% (60%ln, cos Φ=0.41ag)

 c. Adjustable voltage range: 95% ~ 105% Un

 d. Waveform distortion of line voltage at no-load≤5%

 e. Steady short circuit current: 300%ln. Maintaining time: 10s

③ Storage

In the event that the generator is not to be installed on its prime mover immediately, it's recommended that the unit be stored in a cleaned, dry area which is not subject to rapid changes in temperature and humidity.

In the event of long term storage, the generator should be cleaned, tested and dried as required,

before being put into service. See the maintained section of this manual for further information.

④ Installation and adjustment:

1. Generator must be mounted at the clean, dry and well ventilated place. The prime mover and generator should be installed on a public frame, never put them on the cement floor, and ensure the generator frame un-deformed in tightening bolts.

2. Single bearing generators. Single bearing units are provided a SAE adapter and flexible drive discs to match the engine. Close tolerances are maintained in the manufacture of the generator to promote ease of alignment.

The SAE adapter and the engine flywheel housing are designed to match each other, and the outside diameter of drive discs fit in a rabbet in the flywheel so that concentricity is assured, and with no further alignment necessary.

CAUTION: Special steel drive discs are bolted the shaft. In some cases, spacers are used to achieve the proper "XG" dimension. Holes are provided in the periphery of the coupling discs which correspond to tap holes in the engine flywheel.

Grade 8.8 bolts and hard washers are recommended to fit drive discs to the flywheel, don't use split type lock washers, they will cause stress risers, and may result in disc failure.

Shims may be necessary  under the generator feet to insure a solid mounting. Don't force the feet to an

uneven mounting surface, serious problems could result.

3.Two bearing generators: If generator couples with engine by flange rabbet. It's easy to mount. If it's coupled by other way, more attention should be paid to installation, also it may be necessary to shim the generator feet for proper support and alignment. By micrometer aligning the generator and engine as accurately as possible will reduce vibration, increase bearing life, and minimize coupling wear.