User Manual

Selection of Optimum Generators
Example of AC arc welder
AC arc welder is in general single phase load. So when a three phase generator is used for single phase load, it shall be equally
connected to three phase.
Three times more generating power is required for single load welding.
Example of electric motors
(
three-phase squirrel-cage motor
)
Engine generators are used for large and small various type electric
motors.
In general capacity of electric motor is specified in kW or PS.
This shows motor output capacity, not motor input capacity or not required
to operate motor
(
machine
)
. The relation between motor output and input
is shown in the following formula.
Select such a cable length and cross section area so that the voltage drop will remain less than 5%.
Load Current
I
(
A
)
Cable cross section area
S
(
mm
2
)
Cable Length L
(
m
)
1 PS = 0.7355 kW
Efficiency = 85% (three phase induction motor)
Power factor = 0.8 (three phase induction motor)
Input
(
kW
)
Power factor
Input
(
kVA
)
Output
(
kW
)
Efficiency
0.7355 Output
(
PS
)
Efficiency
Input
(
kW
)
Voltage drop e
(
V
)
= × × Current I
(
A
)
× 3
1
58
List of Neutral Point
(
O terminal
)
Allowable Power
50
115
30.3
30.3
60
127
34.1
34.1
254
17.1
17.1
50
115
57.7
57.7
60
127
65.6
65.6
254
32.8
32.8
50
115
107
107
60
127
118
118
254
59.0
59.0
50
115
144
144
60
127
157
157
254
78.5
78.5
50
115
231
115
60
127
262
131
254
131
65.0
50
115
361
180
60
127
394
197
254
197
98.0
SDG13 SDG25 SDG45 SDG60 SDG100 SDG150
Model
Frequency
(
Hz
)
200/220V
Voltage
(
V
)
400
(
380
)
/440V
Voltage
(
V
)
List of current values at a glance
SDG13
30.3
16.0
15.2
34.1
17.1
SDG25
57.7
30.4
28.9
65.6
32.8
SDG45
107
56.2
53.4
118
59.0
SDG60
144
76.0
72.2
157
78.7
SDG100
231
122
115
262
131
SDG125
289
152
144
328
164
SDG150
361
190
180
394
197
SDG220
563
296
281
577
289
SDG300
779
410
390
787
394
SDG400
1,010
532
505
1,050
525
SDG500
1,299
684
650
1,312
656
Model
50Hz
60Hz
Generators are capable of operating following numbers of arc welders.
50
1
60
1
1
50
3
2
2
60
3
2
2
50
3
3
3
2
60
5
4
3
2
SDG25 SDG45 SDG60
50
7
6
5
3
3
60
8
6
6
4
3
2
SDG100
50
10
8
7
5
3
3
60
12
9
8
6
3
3
SDG125
50
13
10
9
6
5
3
60
14
11
10
7
5
3
SDG150
50
18
15
14
10
6
5
60
20
16
15
11
7
6
SDG220
50
14
9
7
60
17
12
10
SDG300
50
19
13
11
60
21
14
12
SDG400
50
24
16
13
60
27
19
15
SDG500
Model
Frequency(Hz)
180A
200A
250A
300A
400A
500A
Note:Numbers of welders in the above table are for such ones without condensers equipped for reference purpose only. When using generators for extremely low
efficientwelders, reduce the numbers of welders. When using generators for AC arc welders equipped with condenser, it is necessary to be very careful for
self-exciting phenomena (Output voltage of generator extremely increases in case of no load or light load).
The above table shows the numbers of welders when operating 40%. In case of more Percentage than 40%, reduce the numbers of welders. When using
generators for more welders than 2 units , connect evenly it to each welder, not concentrating one unit only.
Motor starting capacity
50
10.5
4
7.5
6
7.5
60
13
4.5
9
6.8
9
50
20
6.5
15.1
9.8
15.1
60
25
7.5
18.8
11.3
18.8
50
37
12
27.9
18
27.9
60
45
14
34
21
34
50
50
17
37.7
22.5
37.7
60
60
19
45.3
28.5
45.3
SDG13 SDG25 SDG45 SDG60
50
80
26
60.4
39
60.4
60
100
32
75.5
48
75.5
SDG100
50
125
43
94.4
64.5
94.4
60
150
51
113
76.5
113
SDG150
50
100
35
75.5
52.5
75.5
60
125
43
94.4
64.5
94.4
SDG125
Motor capacity
Direct
start
50
200
68
147
102
147
60
220
76
166
114
166
SDG220
50
270
91
188
137
188
60
300
102
226
153
226
SDG300
50
350
130
265
195
265
60
400
145
302
218
302
SDG400
50
450
160
340
240
340
60
500
181
377
272
377
SDG500
Motor capacity
Direct
start
Length L
(
m
)
Cross section area S
(
mm
2
)
Leakage Protection Device and Grounding Method
Leakage Protection Device
This machine is equipped with a leakage relay which detects
leakage caused by a defective insulation of working load to prevent
an accident such as an electric shock by shutting down the circuit.
However, for additional safety, install ground fault circuit interrupter
(
GFCI
)
for each load equipment close to the load equipment. The
sensitivity current of the leakage relay is 30mA.
Grounding Method
<Procedure>
Connect a lead wire fitted with a ground rod to the leakage relay
grounding terminal
(
E
)
of the three-phase output terminal board.
1.Connect the generator machine ground terminal of the package to
ground.
2.Be sure to ground the package of the load equipment as well.
3.These grounding must be carried out in accordance with local
regulations.
200V
380V
400V
220V
440V
Unit: ampere (A)
231
(
219
)
15.2
(
16.0
)
15.2
(
16.0
)
231
(
219
)
28.9
(
30.4
)
28.9
(
30.4
)
231
(
219
)
53.5
(
56.2
)
53.5
(
56.2
)
231
(
219
)
72.0
(
76.0
)
72.0
(
76.0
)
231
(
219
)
115
(
121.5
)
57.0
(
60.8
)
231
(
219
)
180
(
190
)
90.0
(
95.0
)
50
115
289
144
100
100100
100
50
100
100
80
100
80
60
127
328
164
254
164
82.0
SDG125
231
(
219
)
144
(
158
)
72.0
(
79.0
)
Simplified formula to estimate voltage drop according to
cable length and working current:
The motor capacities in the above table are only for reference purpose. The generator capacities vary upon instantaneous voltage drop, motor start class, efficiency,
old and new type machine.
The instantaneous voltage drop when motor starts shall be within 30% of no load voltage. Motor starting kVA shall be 7 kVA per one
(
1
)
kW.
Motor efficiency shall be 85% and load 90%.
When operating many motor loads
(
starting by turns one by one
)
and total capacity of the loads within the values in the above table, it can operate as many loads as
expected. But the total capacity of the motors which are operated first shall be within the capacity at direct start instantaneous start.
The engine load of the engine complete with turbo-charger sometimes may be influenced by engine net average efficient pressure.
Allowable ampere
3 phase average
(
A
)
Allowable ampere
Single phase
(
A
)
Allowable ampere
3 phase average
(
A
)
Allowable ampere
Single phase
(
A
)
Allowable ampere
3 phase average
(
A
)
Allowable ampere
Single phase
(
A
)
Allowable ampere
3 phase average
(
A
)
Allowable ampere
Single phase
(
A
)
50
115
450
563
60
127
462
577
254
231
289
50
115
623
779
60
127
630
787
254
315
394
50
115
808
1,010
60
127
840
1,050
254
420
525
50
115
1,039
1,299
60
127
1,050
1,312
254
525
656
SDG220 SDG300 SDG400 SDG500
Model
Frequency
(
Hz
)
200/220V
Voltage
(
V
)
400
(
380
)
/440V
Voltage
(
V
)
231
(
219
)
225
(
237
)
281
(
296
)
231
(
219
)
312
(
328
)
390
(
410
)
231
(
219
)
404
(
425
)
505
(
532
)
231
(
219
)
520
(
547
)
650
(
684
)
U
V
W
O
E
Grounding rod
Leakage relay
ground terminal
(
E
)
Leakage relay
ground terminal
(
E
)
Independent
grounding method
Independent
grounding method
Machine
grounding terminal
Common
grounding method
Simultaneously
(
kW
)
By turns
(
kW
)
start
(
open
)(
kW
)
start
(
closed
)(
kW
)
Model
Frequency
(
Hz
)
Generator
(
kVA
)
Simultaneously
(
kW
)
By turns
(
kW
)
start
(
open
)(
kW
)
start
(
closed
)(
kW
)
Model
Frequency
(
Hz
)
Generator
(
kVA
)
1 When you use single phase with O terminal at the same time for each phase from Model SDG13S/25S/AS to SDG150S/AS,the unbalance of current value for each
phase should be kept within 50%.When the current values exceed the limit, please note that the output voltages for each phase may be unbalanced.
2 Output ratio shows an allowable output figure of the rated current. (Rated output 100% = it is allowable to use the rated current value until 100%.)
3 Output ratio shows an allowable output figure of the rated current. (Rated output 50% = it is allowable to use the rated current value until 50%.)
4 Output ratio shows an allowable output figure of the rated current. (Rated output 80% = it is allowable to use the rated current value until 80%.)
1
1
1
1
2
2
2
2
2
2
2
4
4
3
Output ratio
Output ratio
Output ratio
Output ratio
Output ratio
Output ratio
Output ratio
Output ratio
14 15