S4L1D-E41 Wdg.

311 - Technical Data Sheet

Standards
STAMFORD industrial alternators meet the requirements of the relevant parts of the IEC 60034 and the relevant
sections of other international standards such as BS5000-3, ISO 8528-3, VDE 0530, NEMA MG1-32, CSA C22.2-
100 and AS 60034. Other standards and certifications can be considered on request.

Quality Assurance
Alternators are manufactured using production procedures having a quality assurance level to BS EN ISO 9001.

Excitation and Voltage Regulators

Excitation System
AVR Type AS440 MX341 MX321 MX322
Voltage Regulation ± 1% ± 1% ± 0.5% ± 0.5% with 4% Engine Governing

Excitation Type Self-Excited PMG PMG PMG

No Load Excitation Voltage (V) 12 - 9

No Load Excitation Current (A) 0.7 - 0.5
Full Load Excitation Voltage (V) 41 - 39
Full Load Excitation Current (A) 2.3 - 2.2
Exciter Time Constant (seconds) 0.105

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Electrical Data
Insulation System Class H
Stator Winding Double Layer Lap
Winding Pitch Two Thirds
Winding Leads 12
Winding Number 311
Number of Poles 4
IP Rating IP23
RFI 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%
Short Circuit Ratio 1/Xd
Steady State X/R Ratio 13.56
50 Hz 60 Hz
Telephone Interference THF<2% TIF<50
Cooling Air 0.8 m³/sec 0.96 m³/sec
Voltage Star 380 400 415 440 416 440 460 480
Voltage Parallel Star 190 200 208 220 208 220 230 240
Voltage Series Delta 220 230 240 254 240 254 266 277
kVA Base Rating (Class H) for
Reactance Values 350 360 360 350 400 435 440 455

Saturated Values in Per Unit at Base Ratings and Voltages

Xd Dir. Axis Synchronous 3.01 2.79 2.59 2.24 3.47 3.38 3.12 2.97
X'd Dir. Axis Transient 0.20 0.19 0.17 0.15 0.21 0.20 0.19 0.18
X''d Dir. Axis Subtransient 0.14 0.13 0.12 0.11 0.15 0.14 0.13 0.12
Xq Quad. Axis Reactance 2.57 2.39 2.22 1.92 2.92 2.84 2.62 2.49
X''q Quad. Axis Subtransient 0.36 0.33 0.31 0.27 0.41 0.40 0.37 0.35
XL Stator Leakage Reactance 0.07 0.06 0.06 0.05 0.08 0.08 0.08 0.07
X2 Negative Sequence Reactance
0.24 0.23 0.21 0.18 0.28 0.27 0.25 0.24
X0 Zero Sequence Reactance 0.10 0.09 0.09 0.07 0.10 0.09 0.09 0.08
Unsaturated Values in Per Unit at Base Ratings and Voltages
Xd Dir. Axis Synchronous 3.61 3.35 3.11 2.69 4.17 4.05 3.75 3.56
X'd Dir. Axis Transient 0.23 0.21 0.20 0.17 0.24 0.23 0.21 0.20
X''d Dir. Axis Subtransient 0.17 0.16 0.15 0.13 0.17 0.17 0.15 0.15
Xq Quad. Axis Reactance 2.65 2.46 2.29 1.98 3.00 2.92 2.70 2.57
X''q Quad. Axis Subtransient 0.43 0.40 0.37 0.32 0.49 0.48 0.44 0.42
XL Stator Leakage Reactance 0.08 0.07 0.07 0.06 0.10 0.09 0.09 0.08
Xlr Rotor Leakage Reactance 0.12 0.11 0.10 0.09 0.13 0.13 0.12 0.11
X2 Negative Sequence Reactance 0.29 0.27 0.25 0.22 0.33 0.32 0.30 0.29
X0 Zero Sequence Reactance 0.12 0.11 0.10 0.09 0.11 0.11 0.10 0.10

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Time Constants (Seconds)

T’d TRANSIENT TIME CONST. 0.08
T’’d SUB-TRANSTIME CONST. 0.019
T’do O.C. FIELD TIME CONST. 1.7
Ta ARMATURE TIME CONST. 0.018
T’’q SUB-TRANSTIME CONST. 0.0079
0
Resistances in Ohms (Ω) at 22 C
Stator Winding Resistance (Ra), per
0.009
phase for series connected
Rotor Winding Resistance (Rf) 1.19
Exciter Stator Winding Resistance 18
Exciter Rotor Winding Resistance per
0.068
phase
PMG Phase Resistance (Rpmg) per
1.9
phase
Positive Sequence Resistance (R1) 0.01125
Negative Sequence Resistance (R2) 0.01296
Zero Sequence Resistance (R0) 0.01125
Saturation Factors 400V 480V
SG1.0 0.32 0.33
SG1.2 1.3 1.32
Mechanical Data
Shaft and Keys All alternator 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.

1 Bearing 2 Bearings
SAE Adaptor SAE 0.5, 1 N/A
Moment of Inertia 4.6331kgm2 N/A
Weight Wound Stator 470kg N/A
Weight Wound Rotor 400kg N/A
Weight Complete Alternator 1024kg N/A
Shipping weight in a Crate 1095kg N/A
Packing Crate Size 155 x 87 x 107 (cm) N/A
Maximum Over Speed 2250 RPM for two minutes
Bearing Drive End N/A N/A
Bearing Non-Drive End Ball 6314 N/A

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THREE PHASE EFFICIENCY CURVES

50Hz 60Hz

insert curves of 50Hz insert curves of 60Hz

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Locked Rotor Motor Starting Curves - Separately Excited

50Hz
380V 400V 415V 440V
insert
35 curve

30

25
PER CENT TRANSIENT VOLTAGE DIP

20

15

10

0
0 200 400 600 800 1000 1200 1400 1600
LOCKED ROTOR kVA

60Hz
380V 416V 440V 460V 480V
insert
35 curve

30

25
PER CENT TRANSIENT VOLTAGE DIP

20

15

10

0
0 200 400 600 800 1000 1200 1400 1600

LOCKED ROTOR kVA

Transient Voltage Dip Scaling Factor Transient Voltage Rise Scaling Factor
Lagging PF Scaling Factor Lagging PF Scaling Factor
<= 0.4 1.00 <= 0.4 1.25
0.5 0.95 0.5 1.20
0.6 0.90 0.6 1.15
0.7 0.86 0.7 1.10
0.8 0.83 > 0.7 1.00
0.9 0.75
0.95 0.70
1 0.65
Note: To determine % Transient Voltage Dip or Voltage Rise at various PF, multiply
the % Voltage Dip from the curve directly by the Scaling Factor.

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Locked Rotor Motor Starting Curves - Self Excited

50Hz
380V 400V 415V 440V
insert
35 curve

30

25
PER CENT TRANSIENT VOLTAGE DIP

20

15

10

0
0 200 400 600 800 1000 1200 1400
LOCKED ROTOR kVA

60Hz
380V 416V 440V 460V 480V
insert
35 curve

30

25
PER CENT TRANSIENT VOLTAGE DIP

20

15

10

0
0 200 400 600 800 1000 1200 1400

LOCKED ROTOR kVA

Transient Voltage Dip Scaling Factor Transient Voltage Rise Scaling Factor
Lagging PF Scaling Factor Lagging PF Scaling Factor
<= 0.4 1.00 <= 0.4 1.25
0.5 0.95 0.5 1.20
0.6 0.90 0.6 1.15
0.7 0.86 0.7 1.10
0.8 0.83 > 0.7 1.00
0.9 0.75
0.95 0.70
1 0.65
Note: To determine % Transient Voltage Dip or Voltage Rise at various PF, multiply
the % Voltage Dip from the curve directly by the Scaling Factor.

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Three-phase Short Circuit Decrement Curve

50Hz
10000curve
insert

SYMM. ASYMMETRICAL
CURRENT (Amps)

1000

100
0.001 0.01 0.1 1 10
TIME (secs)

Sustained Short Circuit = 1500 Amps

60Hz
10000
insert curve

SYMM. ASYMMETRICAL
CURRENT (Amps)

1000

100
0.001 0.01 0.1 1 10
TIME (secs)

Sustained Short Circuit = 1600 Amps

Note 1 Note 2
The following multiplication factors should be used to The following multiplication factor should be used to convert
adjust the values from curve between time 0.001 the values calculated in accordance with NOTE 1 to those
seconds and the minimum current point in respect of applicable to the various types of short circuit :
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 1.05 440V X 1.06 Sustained x 1.00 x 1.50 x 2.50
415V X 1.09 460V X 1.10 Max. sustained duration 10 sec. 5 sec. 2 sec.
440V X 1.16 480V X 1.15 All other times are unchanged
The sustained current value is constant irrespective of voltage
Note 3
level
Curves are drawn for Star connected machines under no-load
excitation at rated speeds. For other connection the following
If MX322 or digital AVR is used, the sustained shortcircuit multipliers should be applied to current values as shown :
current value is to be multiplied by a factor of 1.1. Parallel Star = Curve current value X 2
Series Delta = Curve current value X 1.732

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Typical Alternator Operating Charts

400V/50Hz

Inser chart

480V/60Hz

Inser chart

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RATINGS AT 0.8 POWER FACTOR

Class - Temp Rise Standby - 163/27°C Standby - 150/40°C Cont. H - 125/40°C Cont. F - 105/40°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 380 415 400 380 370 385 385 370 350 360 360 350 320 325 325 320

kW 304 332 320 304 296 308 308 296 280 288 288 280 256 260 260 256

Efficiency (%) 92.7 92.5 93.0 93.5 92.9 93.0 93.2 93.6 93.2 93.3 93.5 93.8 93.6 93.8 93.9 94.1

kW Input 328 359 344 325 319 331 331 316 300 309 308 298 274 277 277 272

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 435 470 475 490 420 460 460 475 400 435 440 455 365 395 400 410

kW 348 376 380 392 336 368 368 380 320 348 352 364 292 316 320 328

Efficiency (%) 92.9 92.9 93.1 93.2 93.1 93.0 93.3 93.3 93.4 93.3 93.5 93.5 93.7 93.7 93.9 93.9

kW Input 374 405 408 421 361 396 395 407 343 373 377 389 312 337 341 349

De-Rates
All values tabulated above are subject to the following reductions:
- 5% when air inlet filters are fitted
- 3% for every 500 meters by which the operating altitude exceeds 1000 meters above mean sea level
- 3% for every 5°C by which the operational ambient temperature exceeds 40°C
- For any other operating conditions impacting the cooling circuit please refer to applications

Note: Requirement for operating in an ambient exceeding 60°C and altitude exceeding 4000 meters must be
referred to applications.

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/)

Note: Continuous development of our products means that the information contained in our data sheets can change
without notice, and specifications should always be confirmed with Cummins Generator Technologies prior to
purchase.

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