· ND444 is a range of 4 pole, single or 2-bearing advanced AVR controlled industrial or marine AC generators
· 2/3 pitch winding as standard to avoid excessive neutral currents
· Engines adaptors to SAE 0, 1/2, 1, 2 & 3 and coupling discs to SAE 11.5, 14 & 18 are offered for ND444
·Windings offered are 12-wire reconnectable
· Voltages available range up to 690V
·IP22/23 enclosure protection is standard
· Class ‘H’ Insulation with sever environmental protection as standard
· SX440 AVR as standard
·PMG excitation system is optional
Regulation accuracy when no load to full load
SX460 AVR,+/- 1.5%
SX440,AS440,SA465 ,MX341 AVR,+/- 1.0%
MX321 AVR,+/- 0.5%
External and internal voltage control range
> ± 10%
Short time load rating of up to 150% of the ratedcurrent in 2 minutes.
The alterators can carry a load of 110% for onehour in six.
Dynamic voltage characteristics
The transient dip in voltage when rated load is plac-ed on the alternator at 0.8 power factor is 15~20%Un.The recovery time is between 0.2 and 1.0 second.
The alternators permit an unbalanced load of 25%rated current. The deviation of line voltage is less than5%.
Radio interference suppression
The alternators are supplied with interferencesup-pression grade N to VDE 0875.
During the usually short period required for no-breakload transfer the alternators can be operated in parallelregardless of design variant and manufacturer.
The reactive load sharing is assured by a droop co-mpensation device. Thus equipped, the alternators are suitable for parallel operation with other alternators having the same voltage droop or with a supply system.