Man L23/30DF, Project Manual

Page: 277 / 392

The length of the U shall min. be 1 meter the cable
manufacturer can have prescriptions for the min
bending diameters. Se also installation manual
chapter B/G 50 00 0: Alternator cable installation
Dimentioning of the Alternator
Before buying the alternator it has to be decided
which DIN norm has to be fulfilled.
The most normal is DIN6270A (popular said, 12
hours 100%+1hour 110%) at rated surrounding
temperature, for industry air 40 deg C and cooling
medium at rated temp.
If it is an water cooled Generator it is 32 deg C
Insulation class and the construction lifetime has to
be decided.
The insulation can be H=165 deg.C, F=145 deg.C,
B=120 deg.C. in respect of IEC 34
F used as F theoretical lifetime 30 years. The most
common for high voltage machines.
150% lifetime-dimension if the machine is running
with an under temperature for 7 deg.C
200% lifetime-dimension the machine is running
one class lower as insulation F used as B.
Power reductions factors for marine
generators
Classification Cooling air Temp. enc. Red. fact.
H insulation
VDE 40 125 1
GL 45 120 0,96
RINA 50 115 0,93
LR 45 110 0,9
NKK 45 110 0,9
DNV 45 115 0,93
BV 50 110 0,9
ABS 50 115 0,93
MRS 45 120 0,96
Classification Cooling air Temp. enc. Red. fact.
F insulation
VDE 40 105 0,93
GL 45 100 0,89
Classification Cooling air Temp. enc. Red. fact.
RINA 50 90 0,86
LR 45 90 0,86
NKK 45 90 0,86
DNV 45 90 0,86
BV 50 90 0,86
ABS 50 95 0,89
MRS 45 100 0,89
Classification Cooling air Temp. enc. Red. fact.
B insulation
VDE 40 80 0,79
GL 45 75 0,76
RINA 50 70 0,73
LR 45 70 0,73
NKK 45 70 0,73
DNV 45 70 0,73
BV 50 70 0,73
ABS 50 70 0,73
MRS 45 75 0,76
Alternator Protection
▪
Alternator protection settings below are all
standard values.
▪
For each individual plant the settings can be
adjusted to the site condition.
▪
Further to below we also recommend imple-
menting Start blocking of the diesel engine in
case of MSB earthing
▪
In case of Differential protection we recommend
to implement trip of excitation.
▪
For Earth fault protection special consideration
must be made due to Island operation, Grid
operation and type of earthing system.
MAN Diesel & Turbo
3700383-8.2
Page 5 (6)
Power Management - Alternator protection
B 17 00 0
L23/30DF, L28/32DF, V28/32S, L28/32S, L28/32H, L27/38S, L27/38, L23/30S,
L23/30H, L21/31S, L21/31, L16/24S, L16/24
2015.11.17