Aksa AGM 100, Руководство пользователя

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13
8.3 LOADING
When planning the electrical distribution system, it is important to
ensure that a balanced load is presented to the generating set. If
loading on one phase is substantially higher than the other phases
it will cause overheating in the alternator windings, imbalance in
the phase to phase output voltage and possible damage to sensitive
3 phase equipment connected to the system. Ensure that no
individual phase current exceeds the current rating of the generating
set. For connection to an existing distribution system, it may be
necessary to reorganize the distribution system to ensure these
loading factors are met..
8.4 POWER FACTOR
The power factor (cos
j
) of the connected load should be determined.
Power factors below 0.8 lagging (inductive) can overload the
generator. The set will provide its kilowatt rating and operate
satisfactorily from 0.8 lagging to unity power factor (1.0). Particular
attention must be given to installations with power factor correction
equipment such as capacitors to ensure that a leading power factor
is never present. This will lead to voltage instability and may result
in damaging overvoltages. Generally whenever the generating set
is supplying the load any power factor correction equipment should
be switched off.
8.5 GROUNDING/EARTHING REQUIREMENTS
The frame of the generating set must be connected to an earth
ground. Since the set is mounted on vibration isolators, the ground
connection must be flexible to avoid possible breakage due to
vibration.
Ground connection cables or straps should have at least full load
current carrying capacity and meet applicable regulations.
8.6 ALTERNATOR RECONNECTION
Most alternators can be reconnected to suit different output
voltages. Ensure that all other components such as circuit breakers,
current transformers, cables and ammeters are suitable before
operating at a different voltage.
8.7 PARALLEL RUNNING
Extra equipment must be fitted for the standard generating sets
to be operated in parallel with other generating sets or with mains
power.
8.8 INSULATION TEST
Before starting the generating set after installation, test the insulation
resistance of the windings. The Automatic Voltage Regulator (AVR)
should be disconnected and the rotating diodes either shorted out
with temporary links or disconnected. Any control wiring must also
be disconnected.
A 500V Megger or similar instrument should be used. Disconnect
any earthing conductor connected between neutral and earth and
megger an output terminal to earth. The insulation resistance should
be in excess of 1M to earth. Should the insulation resistance be
less than 1M the winding must be dried out.
Table 8.1 Current carrying capacity of power cables (PVC - ISOLATED CABLES YVV
(NYY) SUTABLE TO 0.6/1 KV VDE NORMS AND TS)
CABLE
SECTION
(mm
2
)
0,6/1 KV, NYY TYPE CABLE CURRENT CAPACITY
2.5
4
6
10
16
25
35
50
70
95
120
150
185
240
Soil 25°C at air
36
46
58
77
100
130
155
185
230
275
315
355
400
465
25
34
44
60
80
105
130
160
200
245
285
325
370
435
Multiple
Core
Multiple
Core
Multiple
Core
Single
Core
40°C at air
22
30
38
53
71
94
114
138
176
212
248
238
322
380
25
33
42
57
76
101
123
155
191
228
267
305
347
-
21
28
36
50
67
88
110
138
170
205
245
271
310
-
HO7RN-F
Table 8.2 Recommended cable cross section.
STAND-BY POWER FULL LOAD CURRENT CABLE CURRENT CAPACITY RECOMMENDED
(kVA) (Ampere) (Ampere) CABLE SECTION
U=400 Vac COS = 0,8
(mm
2
)
GENERATING SETS
24 - 30 38 71 4 x 16
35 - 40 61 71 4 x 16
60 - 65 103 114 3 X ( 35 / 16 )
80 - 85 122 138 3 X ( 50 / 25 )
95 - 105 150 176 3 X ( 70 / 35 )
120 - 130 180 212 3 X ( 95 / 50 )
j
13
8.3 LOADING
When planning the electrical distribution system, it is important to
ensure that a balanced load is presented to the generating set. If
loading on one phase is substantially higher than the other phases
it will cause overheating in the alternator windings, imbalance in
the phase to phase output voltage and possible damage to sensitive
3 phase equipment connected to the system. Ensure that no
individual phase current exceeds the current rating of the generating
set. For connection to an existing distribution system, it may be
necessary to reorganize the distribution system to ensure these
loading factors are met..
8.4 POWER FACTOR
The power factor (cos
j
) of the connected load should be determined.
Power factors below 0.8 lagging (inductive) can overload the
generator. The set will provide its kilowatt rating and operate
satisfactorily from 0.8 lagging to unity power factor (1.0). Particular
attention must be given to installations with power factor correction
equipment such as capacitors to ensure that a leading power factor
is never present. This will lead to voltage instability and may result
in damaging overvoltages. Generally whenever the generating set
is supplying the load any power factor correction equipment should
be switched off.
8.5 GROUNDING/EARTHING REQUIREMENTS
The frame of the generating set must be connected to an earth
ground. Since the set is mounted on vibration isolators, the ground
connection must be flexible to avoid possible breakage due to
vibration.
Ground connection cables or straps should have at least full load
current carrying capacity and meet applicable regulations.
8.6 ALTERNATOR RECONNECTION
Most alternators can be reconnected to suit different output
voltages. Ensure that all other components such as circuit breakers,
current transformers, cables and ammeters are suitable before
operating at a different voltage.
8.7 PARALLEL RUNNING
Extra equipment must be fitted for the standard generating sets
to be operated in parallel with other generating sets or with mains
power.
8.8 INSULATION TEST
Before starting the generating set after installation, test the insulation
resistance of the windings. The Automatic Voltage Regulator (AVR)
should be disconnected and the rotating diodes either shorted out
with temporary links or disconnected. Any control wiring must also
be disconnected.
A 500V Megger or similar instrument should be used. Disconnect
any earthing conductor connected between neutral and earth and
megger an output terminal to earth. The insulation resistance should
be in excess of 1M to earth. Should the insulation resistance be
less than 1M the winding must be dried out.
Table 8.1 Current carrying capacity of power cables (PVC - ISOLATED CABLES YVV
(NYY) SUTABLE TO 0.6/1 KV VDE NORMS AND TS)
CABLE
SECTION
(mm
2
)
0,6/1 KV, NYY TYPE CABLE CURRENT CAPACITY
2.5
4
6
10
16
25
35
50
70
95
120
150
185
240
Soil 25°C at air
36
46
58
77
100
130
155
185
230
275
315
355
400
465
25
34
44
60
80
105
130
160
200
245
285
325
370
435
Multiple
Core
Multiple
Core
Multiple
Core
Single
Core
40°C at air
22
30
38
53
71
94
114
138
176
212
248
238
322
380
25
33
42
57
76
101
123
155
191
228
267
305
347
-
21
28
36
50
67
88
110
138
170
205
245
271
310
-
HO7RN-F
Table 8.2 Recommended cable cross section.
STAND-BY POWER FULL LOAD CURRENT CABLE CURRENT CAPACITY RECOMMENDED
(kVA) (Ampere) (Ampere) CABLE SECTION
U=400 Vac COS = 0,8
(mm
2
)
GENERATING SETS
24 - 30 38 71 4 x 16
35 - 40 61 71 4 x 16
60 - 65 103 114 3 X ( 35 / 16 )
80 - 85 122 138 3 X ( 50 / 25 )
95 - 105 150 176 3 X ( 70 / 35 )
120 - 130 180 212 3 X ( 95 / 50 )
j