PM734F - Technical Data Sheet Winding 28

2

PM734FSPECIFICATIONS & OPTIONS

TERMINALS & TERMINAL BOXStandard generators feature a main stator with 6 ends brought out to the terminals, which are mounted on the frame at the non-drive end of the generator. A sheet steel terminal box contains the AVR and provides ample space for the customers' wiring and gland arrangements. It has removable panels for easy access.

SHAFT & KEYSAll generator rotors are dynamically balanced to better than BS6861:Part 1 Grade 2.5 for minimum vibration in operation. Two bearing generators are balanced with a half key.

INSULATION/IMPREGNATIONThe insulation system is class 'H', and meets the requirements of UL1446.All wound components are impregnated with materials and processes designed specifically to provide the high build required for static windings and the high mechanical strength required for rotating components.

QUALITY ASSURANCEGenerators are manufactured using production procedures having a quality assurance level to BS EN ISO 9001.

NOTE ON REGULATIONThe stated voltage regulation may not be maintained in the presence of certain radio transmitted signals. Any change in performance will fall within the limits of Criteria 'B' of EN 61000-6-2:2001. At no time will the steady-state voltage regulation exceed 2%.

DE RATESAll values tabulated on page 6 are subject to the following reductions

5% when air inlet filters are fitted.10% when IP44 Filters are fitted.3% for every 500 metres by which the operating altitude exceeds 1000 metres above mean sea level.3% for every 5°C by which the operational ambient temperature exceeds 50°C.

Note: Requirement for operating in an ambient temperature exceeding 60°C must be referred to the factory.

Continuous development of our products entitles us to change specification details without notice, therefore they must not be regarded as binding.

Front cover drawing is typical of the product range.

STANDARDS

STAMFORD AC generators are designed to meet the performance requirements of IEC EN 60034-1. Other international standards, including BS5000, VDE 0530, NEMA MG1-32, AS1359, CSA C22.2, UL and CE; as well as a wide range of international Marine Certification Approvals, can be met on request. For clarification regarding compliance please contact Cummins Generator Technologies.

VOLTAGE REGULATORS

MX341 AVR - STANDARD

This sophisticated Automatic Voltage Regulator(AVR) is incorporated into the Stamford PermanentMagnet Generator (PMG) control system, and isstandard on marine generators of this type.The PMG provides power via the AVR to the mainexciter, giving a source of constant excitation powerindependent of generator output. The main exciteroutput is then fed to the main rotor, through a fullwave bridge, protected by a surge suppressor. TheAVR has in-built protection against sustained over-excitation, caused by internal or external faults. Thisde-excites the machine after a minimum of 5seconds.An engine relief load acceptance feature can enablefull load to be applied to the generator in a singlestep.If three-phase sensing is required with the PMGsystem the MX321 AVR must be used.We recommend three-phase sensing for applicationswith greatly unbalanced or highly non-linear loads.

MX321 AVR

The most sophisticated of all our AVRs combines allthe features of the MX341 with, additionally, three-phase rms sensing, for improved regulation andperformance.Over voltage protection is built-in and short circuitcurrent level adjustments is an optional facility.

WINDINGS & ELECTRICAL PERFORMANCE

All generator stators are wound to 2/3 pitch. Thiseliminates triplen (3rd, 9th, 15th …) harmonics on thevoltage waveform and is found to be the optimumdesign for trouble-free supply of non-linear loads.The 2/3 pitch design avoids excessive neutralcurrents sometimes seen with higher winding pitches,when in parallel with the mains. A fully connecteddamper winding reduces oscillations duringparalleling. This winding, with the 2/3 pitch andcarefully selected pole and tooth designs, ensuresvery low waveform distortion.

3

CONTROL SYSTEM SEPARATELY EXCITED BY P.M.G.

A.V.R. MX341 MX321

VOLTAGE REGULATION ± 1% ± 0.5 % With 4% ENGINE GOVERNING

SUSTAINED SHORT CIRCUIT

INSULATION SYSTEM

PROTECTION

RATED POWER FACTOR

STATOR WINDING

WINDING PITCH

WINDING LEADS

MAIN STATOR RESISTANCE

MAIN ROTOR RESISTANCE

EXCITER STATOR RESISTANCE

EXCITER ROTOR RESISTANCE

R.F.I. SUPPRESSION BS EN 61000-6-2 & BS EN 61000-6-4,VDE 0875G, VDE 0875N. refer to factory for others

WAVEFORM DISTORTION NO LOAD < 1.5% NON-DISTORTING BALANCED LINEAR LOAD < 5.0%

MAXIMUM OVERSPEED 2250 Rev/Min

BEARING DRIVE END BALL. 6232 C3

BEARING NON-DRIVE END BALL. 6319 C3

1 BEARING 2 BEARING

WEIGHT COMP. GENERATOR

WEIGHT WOUND STATOR

WEIGHT WOUND ROTOR

WR² INERTIA

SHIPPING WEIGHTS in a crate

PACKING CRATE SIZE

TELEPHONE INTERFERENCE

COOLING AIR

VOLTAGE STARkVA BASE RATING FOR REACTANCE VALUES

Xd DIR. AXIS SYNCHRONOUS

X'd DIR. AXIS TRANSIENT

X''d DIR. AXIS SUBTRANSIENT

Xq QUAD. AXIS REACTANCE

X''q QUAD. AXIS SUBTRANSIENT

XL LEAKAGE REACTANCE

X2 NEGATIVE SEQUENCE

X0 ZERO SEQUENCE

REACTANCES ARE SATURATED VALUES ARE PER UNIT AT RATING AND VOLTAGE INDICATED

T'd TRANSIENT TIME CONST. 0.154sT''d SUB-TRANSTIME CONST. 0.02sT'do O.C. FIELD TIME CONST. 2.54s

Ta ARMATURE TIME CONST. 0.02sSHORT CIRCUIT RATIO 1/Xd

3.45 m³/sec 7300 cfm

0.14

0.02

0.15

0.02

690V

1925

2.16

0.14

0.10

1.38

0.19

0.03

0.11

1.51

0.21

0.03

660V

1925

2.36

0.14

WINDING 28PM734F

THF<2% TIF<50

3807 kg

48.424 kgm2

216 x 105 x 154(cm) 216 x 105 x 154(cm)

49.3409 kgm2

3913 kg 3876 kg

1908 kg

3840 kg

1908 kg

1565 kg1609 kg

0.8

IP23

CLASS H

REFER TO SHORT CIRCUIT DECREMENT CURVES (page 5)

2.31 Ohms at 22°C

17.5 Ohms at 22°C

DOUBLE LAYER LAP

0.063 Ohms PER PHASE AT 22°C

0.0016 Ohms PER PHASE AT 22°C STAR CONNECTED

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TWO THIRDS

4

PM734FWinding 28

THREE PHASE EFFICIENCY CURVES

Locked Rotor Motor Starting Curve

0

5

10

15

20

25

30

0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000 5500LOCKED ROTOR kVA

PER

CEN

T TR

AN

SIEN

T VO

LTA

GE

DIP

.

660V 690V

5

3-phase 2-phase L-L 1-phase L-Nx 1.00 x 0.87 x 1.30x 1.00 x 1.80 x 3.20x 1.00 x 1.50 x 2.5010 sec. 5 sec. 2 sec.

All other times are unchanged

Three-phase Short Circuit Decrement Curve. No-load Excitation at Rated Speed

InstantaneousMinimum

PM734FWinding 28

Based on star (wye) connection.

SustainedMax. sustained duration

Sustained Short Circuit = 6,230 Amps

NoteThe following multiplication factor should be used to convert the values from curve for thevarious types of short circuit :

1000

10000

100000

0.001 0.01 0.1 1 10TIME (secs)

CURR

ENT

(Am

ps)

SYMMETRICAL

ASYMMETRICAL

Class - Temp Rise

Star (V)

kVA

kW

Efficiency (%)

kW Input

© 2008 TD_PM734F.28.GB_08.08_04_GB

DIMENSIONS

1598

690

1925

1540

96.5

1596

660

1925

96.4

1411

690

1700

1360

96.4

1411

660

1700

96.4

PM734FWinding 28 / 0.8 Power Factor

RATINGS

1540

Cont. B - 70/50°C Cont. F - 90/50°C

1360

60Hz

Barnack Road • Stamford • Lincolnshire • PE9 2NBTel: 00 44 (0)1780 484000 • Fax: 00 44 (0)1780 484100