Komatsu 4D98 Series Shop Manual page 158

IO. Alternator
10.1.7 Service standards
Characteristic Unit
Revolution at 13.5 V (cold at 20%)
rpm
Adjustment voltage V
Standard
1050 or less
14.2-14.8
Standard temperature slope
13.5 V constant output current (hot at 20%)
Coil resistance (at 20°C) Stator
Rotor
VPC
AMm
n
-0.01
4Ol5000 or above
0.108 (phase)
3.45
10-12