Bypass Mode - Toshiba 4200FA CT/XT User Manual

6.2

Bypass Mode

If the UPS unit is severely overloaded or develops an internal fault, power flow is automatically
switched from the main circuit to the Bypass circuit. Power flow through the bypass is shown in the
following illustration. This changeover occurs automatically in less than 4 milliseconds in phase
(Make-Before-Break). If the power flow is transferred to the Bypass circuit because of an overload
and that overload condition ends within a specified period of time, then the power flow will "re-
transfer" to the AC Input Mode (Normal Operation) automatically. If the power flow is transferred to
the Bypass circuit due to a fault condition, then the power flow must be transferred manually
from the UPS's Bypass circuit back to the Inverter circuit after repairing the fault (see "Start-up
Procedure"). If the power flow is transferred to the Bypass circuit due to an overload condition,
then the power flow will automatically transfer from the UPS's Bypass circuit back to the
Inverter circuit after removing the overload (see "Overload Operation").
Power Flow
Input Isolating
Power XFMR
6.3 Bypass Mode for Optional Alternate Input Models
Power Flow
Bypass
Power
Input Isolating
Power XFMR
4200FA CT/XT User's Manual
TOSHIBA
MCCB
Converter
Power flow in Bypass mode
MCCB
Power flow in Bypass mode for the Alternate Input Models
MBS
Bypass
Inverter
Charger/
Chopper
External
Batteries
MBS
Bypass
Converter
Charger/
Chopper
External
Batteries
Output
Power
Output
Inverter
Power
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