Delta NT Series User Manual

14
Chapter 3 Operation Modes
When maintenance is needed and the reserve AC power is normal, the parallel UPS
units can be switched from inverter mode to bypass mode manually with continuous
power delivering to the loads. Under such conditions, the internal power will be
completely cut off except that each parallel UPS's terminals and manual bypass
breaker or switch still have high voltage. As a result, risks will not exist in the parallel
UPS units so service personnel can perform maintenance safely (see Figure 3-9-a
and 3-9-b).
3.10 Hot Standby Redundancy
)RUKRWVWDQGE\UHGXQGDQF\FRQ¿JXUDWLRQV83623LVFRQQHFWHGWRWKHUHVHUYH
AC power of UPS2 (see Figure 3-10-a and 3-10-b). Such configurations could
UHGXFHWKHSUREDELOLW\RISRZHUFXWRႇDQGLPSURYHWKHTXDOLW\RISRZHUVXSSO\
Figure 3-10-a: Status Block of Hot-standby Redundancy (10-200kVA)
RECTIFIER INPUT
RESERVE
MAINS
BREAKER
RESERVE INPUT
BREAKER
MANUAL BYPASS
BREAKER
OUTPUT
BREAKER
Power Flow
BATTERY BANK
Power Flow
STATIC SWITCHINVERTERRECTIFIER
RECTIFIER INPUT
MAINS
BREAKER
RESERVE INPUT
BREAKER
MANUAL BYPASS
BREAKER
OUTPUT
BREAKER
Power Flow
BATTERY BANK
Power Flow
STATIC SWITCHINVERTERRECTIFIER
LOAD
UPS 1
UPS 2
Power Flow
Power Flow
Power Flow
Power Flow
UPS 1 OUTPUT
UPS 2 OUTPUT
RESERVE INPUT

Delta NT Series Specifications

General

Brand	Delta
Model	NT Series
Category	UPS
Language	English