Marelli Motori Generators

Marelli Motori Generators serve as essential power solutions designed to maintain operational continuity and safeguard business productivity during unexpected electrical outages.

In the following sections, we will look at how a generator functions, the main components of a generator, and how a generator operates as a secondary source of electrical power in residential and industrial applications.

How does a generator work?

An electric generator is a device that converts mechanical energy obtained from an external source into electrical energy as the output.

It is important to understand that a generator does not actually ‘create’ electrical energy. Instead, it uses the mechanical energy supplied to it to force the movement of electric charges present in the wire of its windings through an external electric circuit. This flow of electric charges constitutes the output electric current supplied by the generator. This mechanism can be understood by considering the generator to be analogous to a water pump, which causes the flow of water but does not actually ‘create’ the water flowing through it.

The modern-day generator works on the principle of electromagnetic induction discovered by Michael Faraday in 1831-32. Faraday discovered that the above flow of electric charges could be induced by moving an electrical conductor, such as a wire that contains electric charges, in a magnetic field. This movement creates a voltage difference between the two ends of the wire or electrical conductor, which in turn causes the electric charges to flow, thus generating an electric current.

Technical and Features of Marelli Motori Generators

SERIES: MJRM (Low Voltage) / MJHRM (Medium Voltage)
POWER: Up to 12000 kVA
VOLTAGE: Up to 15000 V
FRAME: 315 – 1250
POLES: 4 to 12
FREQUENCY: 50/60 Hz or variable speed
PROTECTION DEGREE (IP): 44 (up to 56 on request)
COOLING METHOD (IC): 81W
AMBIENT TEMPERATURE: 0°C to +60°C
WATER TEMPERATURE: Up to 40°C
AVR: E-Vo up to 630 frame; D-Vo Light above (Low Voltage) / D-Vo Light (Medium Voltage)
BEARINGS: antifriction or sleeve (on request)
APPLICATIONS: Auxiliary Generator, Shaft Generator, Hybrid Machine, Variable speed generator, Off-shore, PTO-PTI system
STANDARDS: IEC 60034-1 – BS 4999-5000 – NEMA MG 1.32
CERTIFICATIONS: Marine Survey Certificate

Main Options of Marelli Motori Generators

Flanged shaft for direct coupling with the engine flywheel (in case of single bearing solution)
Reinforced construction for high linear vibrations
Neutral point terminals in a separate terminal box
Raised feet to match engine baseframe dimensions (B20 – IM1101)
Dedicated current transformer installed on neutral point (differential protection and measurement)
Insulated bearing and earthing brush
Excitation/overboosting PMG mounted on the generator
Arrangement for rotor earth fault protection 64R
Arrangement for vibration sensors

Source: www.marellimotori.com