MXB

Model	MXB
Power	Up to 375 kVA
Voltages	Up to 480 V
Frame	160 ÷ 250
Poles	4
Cooling	IC01 as per IEC 60034-6
IP	IP23 as per IEC 60034-5 (up to IP 44)
Enclosure	ODP - Open Drip Proof
Main Applications	Data center, Emergency, Portable, PRP and COP, Stand-by, UPS
Sector	Power generation

Certificates and testing
Main components
Construction
Technical data
Operating conditions
Auxiliary device
Optional features

Certificates and testing

Applicable standards	Applicable standards Generators are designed in compliance with: IEC 60034 - 1 CEI 2-3 BS 4999 - 5000 VDE 0530 NF 51 - 100 NF 51 - 111 OVE M - 10 NEMA MG 1.32 Generators conform to EU rules UL 1004 - 1 UL 1004 - 4 C22.2 No. 100
Certificate	Certificate Test Certificate supplied with the machine Material certificates in accordance with EN 10204 : 2001 can be supplied

Main components

Housing	Housing Rigid frame, rugged welded steel fabrication (EN 10025 - S235 JR) Frame is provided with side ribs to increase the strength Marelli Generators for continuous duty operation are designed to meet vibration levels per IEC 60034-14, ISO 10816-1 and BS 5000-3
Shield NDE	Shield NDE Aluminium alloy 46100S T6 (from 160 to 225 frame size) Cast iron GJL 300 (250 frame size)
Shaft	Shaft Carbon steel - hot rolled (EN 10025 - S355 JR)
Terminal board	Terminal board Made of Bakelite PF2736 7-pins (from 160 to 180 frame size) 9-pins (from 225 to 250 frame size)
Fan	Fan PA 6.6 up to MXB 180 SC4 included - Aluminum alloy above

Construction

Cooling System	Cooling System IC01 as per IEC 60034-6
Degree of protection	Degree of protection IP 23 as per IEC60034-5 (up to IP 44 from 180 to 250 frame size)
Mounting	Mounting Horizontal single bearing (160 frame size) Horizontal single bearing - IM 2105 from 180 to 250 frame size (double bearing available on request)

Technical data

Stator/Rotor core	Stator/Rotor core Laminated and enamel-insulated on both sides to minimise eddy-current losses
Rotor	Rotor Salient pole type Made by copper wire H class insulated with enamel coating Winding retaining by pass-through bars of high quality steel Rotating rectifier: Graetz diode bridge with 6 diodes Rotors are dynamically balanced
Bearing	Bearing General data Single or double antifriction bearing grease lubricated (ball type) Bearing lifetime >=20'000 hours Bearing selection Antifriction bearings
Impregnation system	Impregnation system Epoxy resin through high quality process
Insulation system	Insulation system Class H for stator and rotor
Protective treatments	Protective treatments Standard impregnation with epoxy resin through high quality process CW1081 on request

Operating conditions

Overloads	Overloads During continuous duty (S1), the following overloads are allowed: 10% for 1 hour 15% for 10 minutes 30% for 4 minutes 50% for 2 minutes These overloads must be occasional and followed by one hour of running at normal load or less
Parallel operations	Parallel operations All generators are provided with an amply sized damper cage and are suitable for parallel operations with other generators, when equipped with the paralleling unit (available on 180, 225 and 250 frame size)
Transient ratings	Transient ratings All generators can be designed to meet specific reactance values (x'd and x''d). Values can be confirmed by contacting Marelli Motori
Three pahse short circuit current	Three pahse short circuit current Generators with auxiliary windings or PMG ensure a three phase short-circuit current (Icc) higher than 3 times the rated current (in): Icc > 3 In for 10 seconds
Radio interference	Radio interference All generators are equipped with Class B Group 1 radio interference filters as defined by EN 55011
THD (Total Harmonic Distortion) / THF	THD (Total Harmonic Distortion) / THF The no-load voltage wave form is sinusoidal with THD content less than 2% / THF < 2%
Vibrations	Vibrations Vibration level is in accordance with ISO 10816. Measurement, evaluation and limits of vibration severity are in accordance with IEC 60034-14

Auxiliary device

AVR model	AVR model AVR model 11000013 - MARK VX Dedicated AVR for optional PMG
AVR position	AVR position On right side viewed from D-End 225 - 250 frame size front mounted
AVR supply	AVR supply Auxiliary winding
Voltage sensing	Voltage sensing Single phase
Accuracy	Accuracy ± 0,5% (@rated load, balanced and not deforming, P.F. 0,8)
EMI filter	EMI filter Included
Limiters	Limiters U/F Under Frequency

Optional features

Options available

-	160	180	225	250
Operating conditions	-
Special voltage including 380V, R3, R6 (LV only)	o	o	o	o
Provision for parallel operation with similar generators with AVR	n/a	o*	o	o
Terminal box	-
IP55 terminal box	o	o	o	o
Large terminal box	n/a	o	n/a	n/a
Separate auxiliary terminal box	n/a	o	o	o
Non-magnetic exit cable panel	n/a	n/a	n/a	o
6-leads winding	n/a	n/a	n/a	o
Heating	-
Anti-condensation heaters (V=220 V)	o	o	o	o
Temperature sensors	-
N. 3 PTC thermistors	o	o	o	o
N. 3 PT100 resistance temperature detectors in stator winding	n/a	o	o	o
N. 1 PT100 on N-End bearing	o	o	o	o
N. 1 PT100 on D-End bearing (for double bearing configuration)	n/a	o	o	o
N. 1 PT100 duplex type on N-End bearing	n/a	o	o	o
N. 1 PT100 duplex type on D-End bearing (for double bearing configuration)	n/a	o	o	o
N. 1 PT100 air inlet	n/a	n/a	n/a	o
N. 1 PT100 air outlet	n/a	n/a	n/a	o
Protection degree	-
Inlet filter	n/a	o	o	o
Inlet + outlet filter (IP43)	n/a	o	o	o
Inlet + outlet filter (IP44)	n/a	o	o	o
Air to fresh water heat exchanger top mounted on generator (IP44)	n/a	n/a	n/a	o
Air to salt water heat exchanger top mounted on generator (IP44)	n/a	n/a	n/a	o
Air to air heat exchanger top mounted on generator	n/a	n/a	n/a	o
AVR	-
Single-phase sensing AVR (Mark VX), side mounted	s	s	o	o
Single-phase sensing AVR (Mark VX), front mounted	n/a	o*	s	s
Three-phase sensing AVR (MEC-20), side mounted	n/a	o*	o	o
Three-phase sensing AVR (MEC-20), front mounted	n/a	o*	n/a	o
Digital AVR D-Vo (mounted on board)	n/a	n/a	n/a	o
Automatic power factor regulator (mounted on board)	n/a	n/a	n/a	o
Painting	-
Non standard colour (MM ref. F96831)	o	o	o	o
Special painting cycle (MM ref. F96819)	o	o	o	o
Special painting cycle (MM ref. F96826)	o	o	o	o
Environmental solutions	-
Tropicalization (CW1081)	o	o	o	o
Excitation system	-
PMG with single-phase AVR (Mark XX) side mounted	o	o	o	o
PMG with single-phase AVR (Mark XX) front mounted	n/a	o*	o	o
PMG with three-phase AVR (MEC-20) side mounted	n/a	o*	o	o
PMG with three-phase AVR (MEC-20) front mounted	n/a	o*	n/a	o
PMG with digital AVR D-Vo (mounted on board)	n/a	n/a	n/a	o
Mechanical configuration	-
Special shaft extension	n/a	n/a	n/a	o
Second shaft extension (as per catalogue)	n/a	n/a	n/a	o
Special housing	n/a	n/a	n/a	o
Neutral point terminal box for B2-B3-B34 construction	n/a	n/a	n/a	o
NDE grease nipple	n/a	n/a	n/a	o
DE grease nipple	n/a	n/a	n/a	o
Other accessories	-
Toothed wheel (n.60 teeth) with provision for speed sensor (sensor not included)	n/a	n/a	n/a	o
64R - Brush connection with rotor for earth fault detection (without protection device)	n/a	n/a	n/a	o
N. 3 CT single core on neutral point (low voltage)	n/a	n/a	n/a	o
*()** this option includes also large terminal box
-	o: optional \| n/a: not available \| s: standard