Hot Standby Redundancy (Only For Dual Input & At Least Two Upss) - Delta Modulon DPH series User Manual

3.3 Hot Standby Redundancy (Only For Dual Input & At Least
Two UPSs)
To provide customers more application choices, the UPS with a dual-input configuration can
have a hot standby redundancy function. If you use two UPSs and wish them to work in hot
standby redundancy mode, please connect the output of UPS1 to the bypass AC source of
UPS 2. Please see Figure 3-23. For more information about the hot standby redundancy
application, please contact service personnel.
In normal condition, it is the UPS 2 inverter that supplies power to the critical loads. Both UPS
1 & UPS 2 tri-color LEDs illuminate green.
When the UPS 2 inverter becomes abnormal, the UPS 2 will automatically transfer to bypass
mode and the UPS 1 inverter will supply power to the critical loads. Under such circumstances,
the UPS 1 tri-color LED illuminates green and the UPS 2 tri-color LED illuminates yellow.
1
Batteries
2
Batteries
(Figure 3-32: Hot Standby Redundancy Diagram (only for Dual Input & at Least Two UPSs))
Delta or non-Delta External Maintenance Bypass Cabinet
Q3
BYPA.
Q2
MAIN
Q1
Q5
Delta or non-Delta External Maintenance Bypass Cabinet
Q3
BYPA.
Q2
MAIN
Q1
Q5
UPS
Static Switch
Q0
Rectifier
UPS
Static Switch
Q0
Rectifier
3-33
3 Operation Modes
Inverter
Q4
Inverter
Q4
LOAD