TOSHIBA
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6.6
EPO (Emergency Power Off) Function
These units are equipped with terminals for receiving an emergency power-off (EPO) "closed
contact" switch command from two locations: (1) a remote location (see Section 4.3 Terminal
Block Details) and (2) from a front panel mounted EPO switch (see Section 6.5 "Front Panel
Layout). This safety feature enables quick shutdown of the UPS 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 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 the AC
input mode (see Section 6.1.1), battery backup mode (see Section 6.1.3), or the circuit bypass
mode (see Section 6.1.2). See 'EMERGENCY OFF' screen in Section 6.1.2 "Shutdown
Procedure." The following figure shows the UPS condition after application of the EPO switch.
Use the Start-up Procedure (see Section 6.11) for restarting the unit.
6.7
Audible Alarm Functions
Audible alarms will sound when the UPS unit is in the battery backup mode, has a fault, has
low battery voltage, or is in an overload condition. The following chart shows the audible alarm
pattern duration for each condition. Time intervals are shown in seconds. The audible alarm
can be stopped by pressing BUZZ STOP on the front panel keypad (see Section 6.5 "Front
Panel Layout").
Condition
Audible pattern
UPS in Battery Backup Mode
(Battery Voltage 100-90%)
UPS Low Battery
(Battery Voltage < 90%)
Overload
Fault
.5 S
.5 S
.5 S
.5 S
1 S
1 S
1 S
7 S