TOSHIBA
7.0 UPS Protection System
7.1 System Protection Features
The following one-line schematic illustrates the electrical locations of the protection devices on
the 80 kVA UPS models.
7.2 System Protection Functions
The following tables show the built-in UPS fault-protection functions of the 80 kVA models.
Built-in UPS Fault Protection Functions
Protection Item
Converter Inverter
Static
Bypass
Charger/
Chopper
Isolating
XFMR
External
Batteries
Output
Power
Input
Power
MCCB
Power Flow
Overcurrent
Input Abnormal Current-Limit
Overload
Over-Voltage /
Under-Voltage
Overheat
Low Battery
Overheat
Inverter Overvoltage
(IVOV) Inverter Undervoltage
(IVUV) UPS Overload
LCD Message INVERTER
OVERVOLTAGE
INVERTER
UNDERVOLTAGE OUTPUT OVERLOAD
Cause Control Malfunction
;
Feedback Erro
r
Overload or short circuit at the load.
Operation Mode Bypass Operation; Chopper and Inverter Stopped
after Fault Inverter Overload: Transfer to bypass; Inverter stopped.
Bypass Overload: Inverter, Chopper, & Bypass stopped.
Audible Alarm Yes: See Section 6.7 Audible Alarm Functions
Visible Alarm Red Fault Lamp On Inverter OL: No Fault Lamp — Bypass OL: Fault Lamp On
Relay Contact
Alarm Fault Relay closed; Bypass Relay closed Inverter OL: Bypass Relay closed
Bypass OL: Bypass Relay open and Fault relay closed
Auto-Retransfer No Inverter OL: Yes, if bypass OK — Bypass OL: No
Protection Item Low Battery Voltage
(
level-1
)
Low Battery Voltage
(
level-2
)
Inverter Output Current Limit
LCD Message Line-4 will read
BATTERY LOW DC UNDERVOLTAGE OUTPUT OVERLOAD
Cause Battery Discharge Battery Shutdown Level
reached Load Inrush current
Operation Mode Battery Dischar ge Sh utdown: No Output
after Fault If Bypass OK, transfer to bypass
If not, current-limit mode
Audible Alarm Yes: See Section 6.7 Audible Alarm Functions
V
isible Alarm Batter
y
Lam
p
Flickers NO NO
Relay Contact
Al
a
rm Low Battery Relay closed Bypass Relay closed
Auto-Retransfer No Yes
,
if b
yp
ass OK
DC circuit overvoltage
(
DCOV
)
Protection Item Memory error (EERR) Internal overheat (OH) DC circuit overcurrent (DCOC)
LCD Messa
e MAIN EEPROM ERROR OVERHEAT
;
INTERNAL DC OVERVOLTAGE DC OVERCURRENT
Cause Control board chi
p
erro
r
Fan failure
;
hi
g
h ambient Cho
pp
er malfunction Inverter / cho
pp
er fault
Operation Mode
after Fault Start is inhibited Bypass operation; chopper and inverter are stopped
Audible Alarm Yes
;
continuous buzze
r
Visible Alarm RED fault lamp On
Relay Contact
Alarm Fault relay closed; bypass relay closed
Auto-Retransfer NO
52 4200FA User’s Manual