Load Imbalance; Supply Transformer - ABB PCS100 UPS-I User Manual

PCS100 UPS-I User Manual 135

17.8 Load Imbalance

Excessive load imbalance can result in high currents in the neutral cables and connection. For load imbalance >10%
contact ABB for more information.

17.9 Supply transformer

During complete electrical system design precaution should be taken for PCS100 UPS-I system supply transformer
capacity, especially for battery models because of battery charging period after PCS100 UPS-I discharging mode.
As fast charging of batteries through PCS100 UPS-I Inverters can be up to 30 minutes additional load on supply
transformer should be taken in consideration.
Note:
Current level during fast charging period can be set between 0% and 40% of inverter rated current, with standard
setting of 10% for battery models.