UCI274G - Winding 311

Technical Data Sheet

 UCI274G
SPECIFICATIONS & OPTIONS

STANDARDS WINDINGS & ELECTRICAL PERFORMANCE

Stamford industrial generators meet the requirements of All generator stators are wound to 2/3 pitch. This eliminates
BS EN 60034 and the relevant section of other international triplen (3rd, 9th, 15th …) harmonics on the voltage waveform
standards such as BS5000, VDE 0530, NEMA MG1-32, IEC34, and is found to be the optimum design for trouble-free supply
CSA C22.2-100, AS1359. of non-linear loads. The 2/3 pitch design avoids excessive
Other standards and certifications can be considered on request. neutral currents sometimes seen with higher winding pitches,
when in parallel with the mains. A fully connected damper
VOLTAGE REGULATORS winding reduces oscillations during paralleling. This winding,
with the 2/3 pitch and carefully selected pole and tooth
SX460 AVR - OBSOLETE designs, ensures very low waveform distortion.

With this self excited control system the main stator supplies TERMINALS & TERMINAL BOX
power via the Automatic Voltage Regulator (AVR) to the exciter
stator. The high efficiency semiconductors of the AVR ensure Standard generators are 3-phase reconnectable with 12 ends
positive build-up from initial low levels of residual voltage. brought out to the terminals, which are mounted on a cover at
The exciter rotor output is fed to the main rotor through a three the non-drive end of the generator. A sheet steel terminal box
phase full wave bridge rectifier. This rectifier is protected by a contains the AVR and provides ample space for the customers'
surge suppressor against surges caused, for example, by short wiring and gland arrangements. It has removable panels for
circuit. easy access.

AS440 AVR - STANDARD SHAFT & KEYS

With this self-excited system the main stator provides power via All generator rotors are dynamically balanced to better than
the AVR to the exciter stator. The high efficiency semi- BS6861:Part 1 Grade 2.5 for minimum vibration in operation.
conductors of the AVR ensure positive build-up from initial low Two bearing generators are balanced with a half key.
levels of residual voltage.
The exciter rotor output is fed to the main rotor through a three-
phase full-wave bridge rectifier. The rectifier is protected by a INSULATION/IMPREGNATION
surge suppressor against surges caused, for example, by short
circuit or out-of-phase paralleling. The insulation system is class 'H'.
The AS440 will support a range of electronic accessories, All wound components are impregnated with materials and
including a 'droop' Current Transformer (CT) to permit parallel processes designed specifically to provide the high build
operation with other ac generators. required for static windings and the high mechanical strength
required for rotating components.
MX341 AVR
QUALITY ASSURANCE
This sophisticated AVR is incorporated into the Stamford
Permanent Magnet Generator (PMG) control system. Generators are manufactured using production procedures
The PMG provides power via the AVR to the main exciter, giving having a quality assurance level to BS EN ISO 9001.
a source of constant excitation power independent of generator
output. The main exciter output is then fed to the main rotor, The stated voltage regulation may not be maintained in the
through a full wave bridge, protected by a surge suppressor. presence of certain radio transmitted signals. Any change in
The AVR has in-built protection against sustained over- performance will fall within the limits of Criteria 'B' of EN 61000-
excitation, caused by internal or external faults. This de-excites 6-2:2001. At no time will the steady-state voltage regulation
the machine after a minimum of 5 seconds. exceed 2%.
An engine relief load acceptance feature can enable full load to
be applied to the generator in a single step. DE RATES
If three-phase sensing is required with the PMG system the
MX321 AVR must be used. All values tabulated on page 8 are subject to the following
We recommend three-phase sensing for applications with reductions
greatly unbalanced or highly non-linear loads.
5% when air inlet filters are fitted.
MX321 AVR 3% for every 500 metres by which the operating altitude
exceeds 1000 metres above mean sea level.
The most sophisticated of all our AVRs combines all the features 3% for every 5°C by which the operational ambient
of the MX341 with, additionally, three-phase rms sensing, for temperature exceeds 40°C.
improved regulation and performance. Note: Requirement for operating in an ambient exceeding
Over voltage protection is built-in and short circuit current level 60°C must be referred to the factory.
adjustments is an optional facility.
NB Continuous development of our products entitles us to
change specification details without notice, therefore they must
not be regarded as binding.

Front cover drawing typical of product range.

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 UCI274G
WINDING 311
CONTROL SYSTEM SEPARATELY EXCITED BY P.M.G.
A.V.R. MX321 MX341
VOLTAGE REGULATION ± 0.5 % ± 1.0 % With 4% ENGINE GOVERNING
SUSTAINED SHORT CIRCUIT REFER TO SHORT CIRCUIT DECREMENT CURVES (page 7)

CONTROL SYSTEM SELF EXCITED

A.V.R. SX460 AS440
VOLTAGE REGULATION ± 1.0 % ± 1.0 % With 4% ENGINE GOVERNING
SUSTAINED SHORT CIRCUIT SERIES 4 CONTROL DOES NOT SUSTAIN A SHORT CIRCUIT CURRENT

INSULATION SYSTEM CLASS H

PROTECTION IP23
RATED POWER FACTOR 0.8
STATOR WINDING DOUBLE LAYER CONCENTRIC
WINDING PITCH TWO THIRDS
WINDING LEADS 12
STATOR WDG. RESISTANCE 0.0199 Ohms PER PHASE AT 22°C SERIES STAR CONNECTED
ROTOR WDG. RESISTANCE 1.69 Ohms at 22°C
EXCITER STATOR RESISTANCE 20 Ohms at 22°C
EXCITER ROTOR RESISTANCE 0.091 Ohms PER PHASE AT 22°C
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. 6315-2RS (ISO)
BEARING NON-DRIVE END BALL. 6310-2RS (ISO)
1 BEARING 2 BEARING
WEIGHT COMP. GENERATOR 580 kg 598 kg
WEIGHT WOUND STATOR 225 kg 225 kg
WEIGHT WOUND ROTOR 210.35 kg 199.39 kg
WR² INERTIA 1.7674 kgm2 1.7169 kgm2
SHIPPING WEIGHTS in a crate 613 kg 630 kg
PACKING CRATE SIZE 123 x 67 x 103 (cm) 123 x 67 x 103 (cm)
50 Hz 60 Hz
TELEPHONE INTERFERENCE THF<2% TIF<50
COOLING AIR 0.514 m³/sec 1090 cfm 0.617 m³/sec 1308 cfm
VOLTAGE SERIES STAR 380/220 400/231 415/240 440/254 416/240 440/254 460/266 480/277
VOLTAGE PARALLEL STAR 190/110 200/115 208/120 220/127 208/120 220/127 230/133 240/138
VOLTAGE SERIES DELTA 220/110 230/115 240/120 254/127 240/120 254/127 266/133 277/138
kVA BASE RATING FOR REACTANCE
182 182 182 N/A 205 218 218 231
VALUES
Xd DIR. AXIS SYNCHRONOUS 2.15 1.94 1.80 - 2.43 2.31 2.11 2.06
X'd DIR. AXIS TRANSIENT 0.19 0.17 0.16 - 0.21 0.20 0.18 0.18
X''d DIR. AXIS SUBTRANSIENT 0.13 0.12 0.11 - 0.15 0.14 0.13 0.12
Xq QUAD. AXIS REACTANCE 1.29 1.16 1.08 - 1.47 1.40 1.28 1.24
X''q QUAD. AXIS SUBTRANSIENT 0.18 0.16 0.15 - 0.18 0.17 0.16 0.15
XL LEAKAGE REACTANCE 0.08 0.07 0.07 - 0.09 0.08 0.08 0.07
X2 NEGATIVE SEQUENCE 0.13 0.12 0.11 - 0.16 0.15 0.13 0.13
X0 ZERO SEQUENCE 0.08 0.07 0.07 - 0.10 0.09 0.08 0.08
REACTANCES ARE SATURATED VALUES ARE PER UNIT AT RATING AND VOLTAGE INDICATED
T'd TRANSIENT TIME CONST. 0.038 s
T''d SUB-TRANSTIME CONST. 0.012 s
T'do O.C. FIELD TIME CONST. 1s
Ta ARMATURE TIME CONST. 0.01 s
SHORT CIRCUIT RATIO 1/Xd

3
 UCI274G
50 Winding 311
Hz THREE PHASE EFFICIENCY CURVES

4
 UCI274G
60 Winding 311
Hz THREE PHASE EFFICIENCY CURVES

5
 UCI274G
Winding 311

Locked Rotor Motor Starting Curve

50
Hz
MX SX
346V 380V 400V 415V 346V 380V 400V 415V
30 30

25 25
.

.
20 20
P E R C E N T T R A N S IE N T V O L T A G E D IP

P E R C E N T T R A N S IE N T V O L T A G E D IP
15 15

10 10

5 5

0 0
0 100 200 300 400 500 600 0 50 100 150 200 250 300 350 400 450 500 550
LOCKED ROTOR kVA LOCKED ROTOR kVA

60
MX Hz SX
380V 416V 440V 460V 480V 380V 416V 440V 460V 480V
30 30

25 25
.

20 20
P E R C E N T T R A N S IE N T V O L T A G E D IP

P E R C E N T T R A N S IE N T V O L T A G E D IP

15 15

10 10

5 5

0 0
0 100 200 300 400 500 600 700 800 0 100 200 300 400 500 600 700
LOCKED ROTOR kVA LOCKED ROTOR kVA

6
 UCI274G

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

Based on star (wye) connection.

50
10000
Hz
SYMMETRICAL

ASYMMETRICAL

1000
CURRENT (Amps)

100

10
0.001 0.01 0.1 1 10
TIME (secs)

Sustained Short Circuit = 850 Amps

60 10000

Hz SYMMETRICAL

ASYMMETRICAL

1000
CURRENT (Amps)

100

10
0.001 0.01 0.1 1 10
TIME (secs)

Sustained Short Circuit = 970 Amps

Note 1 Note 2
The following multiplication factors should be The following multiplication factor should be used to convert the
used to adjust the values from curve between values calculated in accordance with NOTE 1 to those applicable to
time 0.001 seconds and the minimum current the various types of short circuit :
point in respect of nominal operating voltage :

50Hz 60Hz 3-phase 2-phase L-L 1-phase L-N

Voltage Factor Voltage Factor Instantaneous x 1.00 x 0.87 x 1.30
380v X 1.00 416v X 1.00 Minimum x 1.00 x 1.80 x 3.20
400v X 1.07 440v X 1.06 Sustained x 1.00 x 1.50 x 2.50
415v X 1.12 460v X 1.12 Max. sustained duration 10 sec. 5 sec. 2 sec.
480v X 1.17 All other times are unchanged
The sustained current value is constant irrespective of
voltage level Note 3
Curves are drawn for Star (Wye) connected machines. For other
connection the following multipliers should be applied to current
values as shown :

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 UCI274G
Winding 311 / 0.8 Power Factor

RATINGS
Class - Temp Rise Cont. F - 105/40°C Cont. H - 125/40°C Standby - 150/40°C Standby - 163/27°C

Series Star (V) 380 400 415 440 380 400 415 440 380 400 415 440 380 400 415 440
50 Parallel Star (V) 190 200 208 220 190 200 208 220 190 200 208 220 190 200 208 220
Hz Series Delta (V) 220 230 240 254 220 230 240 254 220 230 240 254 220 230 240 254

kVA 164.6 164.6 164.6 N/A 182.0 182.0 182.0 N/A 187.0 187.0 187.0 N/A 200.0 200.0 200.0 N/A

kW 131.7 131.7 131.7 N/A 145.6 145.6 145.6 N/A 149.6 149.6 149.6 N/A 160.0 160.0 160.0 N/A

Efficiency (%) 92.3 92.6 92.8 N/A 92.0 92.3 92.5 N/A 91.9 92.2 92.5 N/A 91.6 92.0 92.2 N/A

kW Input 142.7 142.2 141.9 N/A 158.3 157.7 157.4 N/A 162.8 162.2 161.8 N/A 174.7 173.9 173.5 N/A

Series Star (V) 416 440 460 480 416 440 460 480 416 440 460 480 416 440 460 480
60 Parallel Star (V) 208 220 230 240 208 220 230 240 208 220 230 240 208 220 230 240
Hz
Series Delta (V) 240 254 266 277 240 254 266 277 240 254 266 277 240 254 266 277

kVA 192.8 199.0 199.0 212.2 205.0 218.5 218.5 231.4 213.0 228.8 228.8 250.0 218.5 234.0 234.0 253.3

kW 154.2 159.2 159.2 169.8 164.0 174.8 174.8 185.1 170.4 183.0 183.0 200.0 174.8 187.2 187.2 202.6

Efficiency (%) 92.4 92.7 92.9 93.0 92.2 92.4 92.7 92.7 92.0 92.2 92.5 92.5 91.9 92.1 92.4 92.5

kW Input 166.9 171.7 171.4 182.5 177.9 189.2 188.6 199.7 185.2 198.5 197.9 216.2 190.2 203.3 202.6 219.1

DIMENSIONS

Dimensional and Torsional Drawing

For dimensional and torsional information please refer to the alternator General Arrangement and rotor drawings
available on our website (http://stamford-avk.com/)

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 www.stamford-avk.com

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Stamford and AvK are registered trade marks of Cummins Generator Technologies Ltd
Cummins and the Cummins logo are registered trade marks of Cummins Inc.

UC274G-311-TD-EN-SG-B