Coupling Transformer Enclosure; Coupling Transformer - ABB PCS100 UPS-I User Manual

PCS100 UPS-I User Manual
The main visual difference of the Utility Disconnect MkII is the addition of the cooling fans in the front doors. The
MkI Utility Disconnect has the cooling fans in the bottom.
5.1.3

Coupling Transformer Enclosure

The Coupling Transformer Enclosure houses:
•

Coupling Transformer

• Float Charger
• And various small protection and measuring devices.
DANGER – Hazardous Voltages
An Operator must not open doors or panels marked as containing hazardous voltages. Many
parts in this product, including printed circuit boards operate at lethal voltages. DO NOT
TOUCH components or connections that have voltage present
5.1.4 Coupling Transformer
The Coupling Transformer consists of delta connected primary and star connected secondary.
In the event of an outage the inverter supplies approximately 428 Vac to the primary and the secondary is
connected to the load.
The coupling transformer has 3 main purposes:
Transforms inverter output voltage to match the utility voltage,
–
Transforms the 3-wire inverter voltage (U, V and W) into a 4-wire voltage (L1, L2, L3, & N),
–
Isolation of the inverter common mode voltages from the utility.
–
CAUTION
The star point of the coupling transformer must be connected to the supply neutral. The star point
is the neutral reference while the PCS100 UPS-I inverter is discharging.
Coupling Transformer
Figure 5-4: Coupling Transformer Enclosure
Float Charger
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