Battery backup (on batteries), Epo (emergency power off) function – Toshiba UNINTERRUPTIBLE POWER SYSTEM 1600XP User Manual
Page 38

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1600Xp Series installation and operation manual
Battery Backup (On batteries)
The following illustration shows power flow during the battery backup mode. When commercial AC power
failures occur, the UpS’s batteries instantly begin supplying dC voltage to the UpS’s main inverter circuit.
this circuit changes (inverts) the dC power into AC power. the AC power is available at the output of the
unit.
this back-up process will continue until the UpS’s battery voltage drops below a specific minimum level.
when this occurs, the batteries will stop supplying power to the load. this minimum level is the rated
minimum voltage (Vmin). the rated battery voltage chart on
page
28 shows (Vmin). the battery backup
time and discharge process is explained on
page
28.
EPO (Emergency Power Off) Function
these units are equipped with terminals for receiving an emergency power-off (epo) command via a
closed-contact switch at a remote location (see terminal block details on
page
13 and terminal block
location on
pages
65-66). this safety feature enables quick shut-down of the UpS’s AC output and
battery circuits.
Usually the emergency power off switch is installed in a central location that is easily accessible to
personnel concerned with the operation of the UpS unit and the load equipment connected to it. the epo
function is initiated by pressing the switch to the closed (shutdown) position.
the effect of using the epo switch is the same whether the UpS unit is in AC input mode, battery backup
mode, or the circuit bypass mode. The following figure shows the UPS condition after application of the
epo switch.
POWER FLOW IN BATTERY BACKUP FOR ALL MODELS
Output
Power
Line Filter
*Static Switch
Isolation
Transformer
Input
Power
Input
Fuse
Power Flow
Bypass
* Switches are
solid state
devices.
MCCB
Output
Fuse
Surge
Absorber
Batteries
+
–
Rectifier/
Chopper
Inverter
Negative Bus
POWER FLOW AFTER AN EPO COMMAND FOR ALL MODELS
Output
Power
Line Filter
Inverter
*Static Switch
Isolation
Transformer
Input
Power
Input
Fuse
Power Flow
Bypass
* Switches are
solid state
devices.
MCCB
Output
Fuse
Surge
Absorber
Batteries
+
–
Rectifier/
Chopper
Negative Bus