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OPM_LPS_31E_8K0_20K_1GB_V010.doc
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Operating
Manual
LP 31
/ 8-10-15-20
kVA
2. FUNCTIONAL EXPLANATION
2.1 THE PRINCIPLES OF OPERATION
The
LP 31
UPS stores electric energy in batteries housed in the unit.
This allows the UPS to supply output power even when the incoming mains power is cut OFF
completely.
Energy is stored as Direct Current (DC), while input and output energy must be Alternating
Current (AC).
Therefore the UPS contains an input converter (AC to DC) and an output converter (DC to
AC) (fig.1).
The
LP 31
UPS is a SECOND GENERATION On-line UPS with:
•
battery not in line with the DC link, resulting in:
- enhanced battery life;
- optimal battery charging;
•
full wave input converter with power factor correction;
•
extremely wide input voltage and input frequency tolerance;
•
output converter (inverter) using IGBT technology.
2.2 NORMAL
CONDITIONS
Under normal conditions (see section 9 - Input Specifications), energy from the mains is
channelled through the input converter, which supplies the output converter and, together with
the battery charger, keeps the battery fully charged.
The output converter synthesises a completely new AC output sine wave to supply the load
(electrical equipment).
Figure 1 - Block diagram, mains present
(
1
) RFI = Radio Frequency Interference
(
2
) PF = Power Factor
