Emerson 7400 - Manual (Page 18)

9
Series 7400 Single Phase 1+N UPS
A “Common battery” option kit contains a DCCT (DC Current
Transformers) which are fitted to the battery power lines and
monitored by the parallel control logic. Each module monitors its
battery charge current and compares it with the charge current
provided by the other module. This enables a module to match its
charge current to that of its partner by effecting fine voltage control
over the rectifier section.
The components used by the Common Battery Option are
contained in a separate cabinet known as the Common Battery
Panel.
Figure 5: ‘Common Battery’ configuration
1.2.7 Common Battery
RECTIFIER
STATIC
SWITCH
INVERTER
Mains
Supply
UPS
Output
Supply
BATTERY
1+1 PARALLEL CONTROL
RECTIFIER
STATIC
SWITCH
INVERTER
Mains
Supply
1+1 PARALLEL CONTROL
Common Batt. Panel
Control
Logic
Bypass
Supply
Bypass
Supply