Figure 1.2 Single Line Diagram-Bypass Operation - Mitsubishi Electric 2033G Series Owner Technical Manual

MITSUBISHI
ELECTRIC
FIGURE 1.2 Single Line Diagram - Bypass Operation. Load fed through static bypass line.
CB
AC input
User
supplied
Referring to Figure 1.2, the Internal Bypass line is a Hard-wired line through 52S which supplies
the unconditioned bypass input power to the critical load. Upon switching to the Internal Bypass
line, the Static Transfer Switch line through CB3 (herein after STS contactor CB3) supplies the
power immediately, and then the Internal Bypass line through 52S supplies the power. In the
event of a switching to the Bypass line, the power to the critical load will be uninterrupted. The
purpose of this Internal Bypass line is to route power to the critical load while the UPS module is
de-energized (converter and inverter), and during Start-up before the system is fully operational.
The internal control system determines the operation of the two paths, with the load powered
from the inverter being the normal operation.
Referring to Figure 1.3, in the event of AC input power failure or abnormal condition, the battery
will immediately supply the DC power required by the Inverter to maintain continuous AC power
to the critical load until a) The battery capacity expires and the inverter turns off. (This means
a state called a low battery shutdown.) b) AC input power is restored after which the converter
will power the inverter and simultaneously recharge the batteries.
A fully charged battery will provide power for the specified time at the rated load, or longer at
reduced load.
When AC input power is recovered after a low battery shutdown, the Internal Bypass line
supplies the unconditioned bypass input power to the critical load. Simultaneously, the
Converter automatically restarts operation, recharges the batteries and the Inverter
automatically restart its operation. And then the UPS transfers the power supply from Bypass
line to Inverter output without operator intervention.
2033G SERIES UPS
OWNERS / TECHNICAL MANUAL
CONVERTER
/ CHARGER
FI
CB1
CB2
External
BATTERY
MITSUBISHI ELECTRIC 2033G SERIES UPS
52S
Static Transfer
Switch
CB3
INVERTER
FO
52C
UPS Module
FB
Power Flow
Not in Use
CB
Page Number:
1-8
Output