Liebert NX UPS System Multi Module UPS-1+N, Redundant Control Power Supply Board, Socket Outlet

Operation

5.1.4Redundant Control Power Supply Board

The UPS is equipped with two identical and fully redundant control power supply boards. Each of them takes inputs from the AC and DC sources. When one of the sources or even if one of the control power boards fails, the UPS system can still operate normally. This feature further enhances the reli- ability of the system.

5.1.5Socket Outlet

One single-phase Shuko-type universal outlet of 3A current handling capability provides nominal UPS output voltage of up to 3A current capacity for the ease of testing, commissioning & servicing of the UPS.

5.2Multi Module UPS—1+N

Multi-module UPS are formed by several “single unit” UPS modules to constitute “1+N”system where groups of one or more, up to six, single units operate together for the purpose of providing additional power or reliability or both. The load is equally shared between any paralleled UPS.

Figure 29 1+N multi-module UPS with external maintenance bypass switch

Qin UPS1

Supplied by Others

Input Mains Supply

L1,L2,L3,N

Qin UPS2

Input Mains Supply

Bypass Mains Supply

L1,L2,L3,N L1,L2,L3,N

Qin UPS3

Input Mains Supply

Bypass Mains Supply

L1,L2,L3,N L1,L2,L3,N

Qin Ext

Byp

L1,L2,L3,N

CB1

RECTIFIER

STATIC

SWITCH

INVERTER

UPS1

L1,L2,L3,N OUTPUT

Qout UPS1

Qout all UPS

CB1

RECTIFIER

STATIC

SWITCH

INVERTER

UPS2

L1,L2,L3,N OUTPUT

Qout UPS2

Distribution Cabinet

CB1

RECTIFIER

STATIC

SWITCH

INVERTER

UPS3

OUTPUT

L1,L2,L3,N

Qout UPS3

Qout Byp

Further, single unit or 1+N groups may be configured as “distributed redundant” systems with inde- pendent outputs that nevertheless are synchronised through a Load Bus Synchroniser (LBS) so that critical loads can be seamlessly transferred from one system to another. See 5.3 - Modes of Opera- tion for more information.

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