Toshiba 1600EP Power Supply User Manual


 
24
1600EP Series Instruction Manual
Online Mode
Online Mode (Run operation)
The following illustration shows circuit power ow when the UPS is operating normally in the Online
mode. The UPS rectier, including a boost chopper circuit, converts AC input power to DC power. The
boost chopper circuit maintains a constant voltage, with current limiting, for charging the batteries. It also
supplies a DC voltage of the proper level to the inverter section. The inverter section generates a high
quality sine wave output voltage. The unit’s batteries are always maintained in a constantly charged state
when the UPS is in the run operation mode.
Static-Bypass Mode (Stop operation)
If the UPS unit is severely overloaded or develops an internal fault, power ow is automatically switched
from the unit’s main circuit to the bypass circuit. Power ow through the bypass is shown in the following
illustration. This change-over occurs automatically in phase in less than 4 milliseconds. The switching
period is not long enough to cause interruptions to occur in most loads.
If the power ow is transferred to the bypass circuit because of an overload and that overload condition •
ends within a specied period of time then the power ow will be transferred back to the Online mode
(run operation) automatically.
If the power ow is transferred to the bypass circuit due to an external • fault the UPS will shut down
power through the bypass to the load and indicate a system fault message.
If the power ow is transferred to the bypass circuit due to an internal fault the UPS will continue to •
supply power to the load through the bypass and indicate a system fault message (see system fault
message DC-OC on page 43).
If the power ow is transferred to the bypass circuit due to an overload condition (see system warning •
message  on page 39 and AUTO RETRANSFER on page 41), then the power
ow will automatically transfer from the UPS’s bypass circuit back to the inverter circuit after removing
the overload if set to do so (see auto-transfer setting on page 35).
POWER FLOW IN ONLINE MODE FOR ALL MODELS
POWER FLOW IN BYPASS MODE FOR ALL MODELS