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UPS for 480 Vac Grid, User Guide, doc. rel.4.0
calibrated, the battery voltage reading would be displayed as 270 Vdc negative and 270 Vdc
positive.
To detect and correct any inaccuracy in the UPS’s display of the battery voltage:
1.
Measure the actual battery voltage with a calibrated voltmeter. There are labeled battery dc
bus bars inside the UPS. Carefully, observing all safety precautions, measure the voltage
between the negative (“–”) battery bus bar (Figure 52) and the midpoint bus (Figure 52).
Figure 52: Battery bus bars and midpoint bus bar
