KR series
（
6
-
10kVA
）
user
’s manual
- 11 -
Short-circuit
Long beep
INV. Off, Bypass on,
Fault on, Output on
“Output 220.0V
OUTPUT SHORT”
Protected
Note: If commercial power recovers after low-voltage protection to battery, the product will restart and charge batteries.
3.2 Parallel System Principle
3.2.1Working Principle
Parallel flow equalization of AC input is mainly through rapid adjustment of paralleled single’s
output waveform, amplitude and phase, then make them strictly the same, to achieve current
sharing purposes. Any difference of the voltage amplitude or phase may have a great
circulation; seriously, it may cause overload or inverter damage. As the high-power UPS itself
may have large interference, therefore, parallel systems must have strong anti-interference
features, thus ensure the system reliability service.
3.2.2Working Mode
Diagram of Parallel system is shown as Fig.3.2-1.
PFC
DC/DC
PFC
DC/DC
Bypass Switch
Inverter
Load
Battery
Main(UPS2)
AC Input
Bypass Switch
Inverter
Battery
Main(UPS1)
Fig.3.2-1 Diagram of Parallel System
