User Manual 10H52188UM60 - Rev. 2 - 09/2012
13
Liebert NXC
Battery
Chapter 2
Battery
This chapter provides relevant information about the battery, including a short introduction, and information on battery
safety, battery power cables, battery maintenance and recycling.
2.1
Brief Introduction
The UPS battery string consists of batteries connected in series in order to supply the rated DC input voltage for the UPS
inverter. The battery backup time (that is, the time that the battery can continue to supply the load for when the mains supply
is interrupted) depends on load level and the ampere-hour capacity of the batteries. Therefore, it may be necessary to connect
several battery strings in parallel.
The NXC UPS includes a battery compartment that can accommodate the internal batteries.
In the case of UPS configurations without internal batteries, the unit must be connected to an external battery cabinet. The
external battery is fitted with a protective device that can be used to isolate the battery in the event of maintenance work. This
device is mounted inside or in close proximity to the battery cabinet.
Note
1. The external battery cabinet for the UPS can hold up to 128 12 V batteries.
2. It must be possible to disconnect the battery from the UPS when carrying out maintenance or service work. The fuse holder can be
switched on or off manually.
3. The requirements of the EC directives are satisfied when battery cabinets are used with original accessories. If alternative batteries are
used, you must ensure that the applicable EC directives are met, and declare conformity.
2.2
Safety
Take special care when working with the batteries associated with the UPS. When all the blocks are connected together, the
battery string voltage can be up to 460 Vdc. This is potentially lethal. Please follow the precautions for high voltage operation.
Only qualified personnel are allowed to install and maintain the battery. To ensure safety, the external batteries are to be
installed inside a lockable cabinet or in a purpose-designed, dedicated battery room, so that they are only accessible to
qualified maintenance personnel.
During battery maintenance, pay attention to the following items:
Ensure that the UPS is in maintenance mode.
The battery block number setting in the background software must be consistent with the actual battery block number.
The battery complete Ah setting must be done in the background software.
If the battery fuses are blown, the UPS must be repaired by authorized service personnel. The fuses must be replaced
using the same type as those that were delivered with the UPS and must be supplied by the same manufacturer.
Note
Full safety instructions concerning the use and maintenance of UPS batteries are provided in the appropriate battery manufacturers’
manuals. The battery safety information contained in this section relates to key considerations that must be taken into account during the
installation design process and might affect the design outcome depending on localized conditions.
