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UPS for 480 Vac Grid, User Guide, doc. rel.4.0
Figure 59: Boost Current Calibration
The ideal boost voltages are ± 425 Vdc.
The voltages can be adjusted up or down by up to 1.875 volts.
Modification of the boost voltage should be done when there is no load on the
UPS, and no ac input – the input circuit breakers are in the “OFF” position.
8.2.3.6.
Adjusting the battery voltage (the “buck” voltage)
The fields labeled Battery positive dc and Battery negative dc effect the voltage between the
positive battery bus bar and the dc midpoint, and between the negative battery bus bar and the
dc midpoint.
The ideal buck voltages are ± 270 Vdc for strings of 40 batteries.
This function enables you to adjust the “buck” voltage up or down by a maximum of 1.875
volts.
