Liebert NXC 40kVA - Battery Disposal

44 Chapter 6 Battery
Liebert NXC 30kVA And 40kVA UPS User Manual
Chapter 6 Battery
This chapter introduces the battery, including the battery safety, installation and maintenance information, battery
protection function, as well as the connection of BCB box (optional).
6.1 Introduction
The UPS battery string is composed of several batteries in series connection and provides rated DC input voltage for
the UPS inverter. The required battery backup time (i.e. the time for battery to supply load upon mains failure) is
subject to the ampere-hour value of the battery. Sometimes, it is necessary to connect several strings of battery in
parallel.
To facilitate the UPS installation, the battery is generally installed on the specially designed battery rack or in the
battery room.
During the maintenance or repair, the battery must be disconnected from the UPS. This operation may be realized by
the battery circuit breaker of proper capacity. This circuit breaker shall be located as close as possible to the battery
connecting terminal, and the wiring distance of the power and signal cables connected to the UPS shall be minimized.
When several strings of battery are paralleled to increase the battery backup time, disconnecting device shall be
equipped, so that the maintenance operation on a certain battery string will not affect the normal operation of other
battery strings.
6.2 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 432Vdc. 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 service personnel.
Confirm that the battery switch has been disconnected before battery maintenance.
Warning: hazardous battery voltage present behind covers
1. No user-serviceable parts are located behind covers that require a tool for their removal. Only qualified service personnel are
authorized to remove such covers.
2. Before working on the copper bars connected to the external battery, please ensure they are disconnected from all power
supplies.
Proper connection mode Improper connection mode
Tighten the terminal bolt of the battery with
specified torque
Too large or too small torque may cause poor connection of the terminal. Under
certain conditions, the terminal may have arcing or heat accumulation, which
finally will cause fire
3. Observe the following safety precautions when working on the batteries:
1) The battery shall be firmly and reliably connected. After the connection is completed, the screw connections between all the
terminals and the batteries shall be calibrated. The requirements on torque specified in the specifications or user manual provided