Mitsubishi Electric 9900D Series Owner Technical Manual page 15

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 UPS whenever the system is in
the Parallel Operation.
!
The Bypass Input circuit breaker (MCCB) for protection of the UPS and cables are field
supplied and field installed. (See WARNING 4 on page 1-5).
NOTE
B) Bypass Operation: Load Power supplied through UPS internal static bypass line.
Figure 1.2
Single Line Diagram - Bypass Operation: Load fed through static bypass line
CB
Bypass
Input
User
supplied
MCCB
CB
AC
input
User
supplied
MCCB
CB
Battery
Cabinet
External
BATTERY
Power Flow
Not in Use
Referring to Figure 1.2: The Internal Bypass line is a Hard-wired line through 52S which supplies
the critical load with unconditioned bypass input power. Upon switching to the Internal Bypass line,
9900D SERIES UPS
OWNERS / TECHNICAL MANUAL
Bypass Module
CB 3
CONVERTER / INVERTER
CB 1
CHARGER
CONVERTER / INVERTER
CB 1
CHARGER
CONVERTER / INVERTER
CB 1
CHARGER
MITSUBISHI ELECTRIC 9900D SERIES UPS
52 S
Static Transfer
Switch
52 C
UPS Module
52 C
UPS Module
52 C
UPS Module
Page Number:
1-8
Output
–
3 5 UPS
M odules
UPS
CABINET