Operation Overview; Figure 1.1 Single Line Diagram-Normal Operation - Mitsubishi Electric 9800A Owner Technical Manual

MITSUBISHI
ELECTRIC

1.4 OPERATION OVERVIEW

The UPS provides two power paths between the utility source and the critical load.
Figure 1.1 shows the path for normal operation, with the load powered from the inverter.
Figure 1.2 shows the path for bypass operation, with the load supplied through the static
bypass line.
A) Normal operation: Load power supplied by each system UPS inverter.
Figure 1.1 Single Line Diagram - Normal Operation: Load powered by UPS inverters
AC Bypass
Input
User supplied
MCCB
AC input
CB1
During normal operation, the path through the UPS inverters is used to power the load.
Referring to Figure 1.1: For each system UPS, the Input AC power is converted to DC by
the Rectifier. DC power is utilized to charge the UPS battery and to provide power to the
Inverter. The Inverter converts the DC power to clean AC power to supply the critical load.
The conversion - inversion process eliminates any voltage transients or fluctuations
existing in the input power before it reaches the critical load.
The power drawn by the critical load is equally shared between all system UPS.
In the event of a UPS module failure, the critical load power will be continually supplied
and shared by all other system UPS.
In the event of a load overcurrent, all system UPS will transfer to bypass without
interruption to the critical load.
MITSUBISHI ELECTRIC 9800A SERIES UPS
9800A SERIES UPS
OWNERS / TECHNICAL MANUAL
CB
RECTIFIER
Battery cabinet
Static Transfer
Switch
CB3
INVERTER
52S
52C
CB2 Power Flow
Not in Use
UPS Module
Page Number:
1-7
Output