Emerson 60HZ - Manual (Page 25)

Battery Installation
19
3.0 B
ATTERY
I
NSTALLATION
3.1 Introduction
Liebert recommends that the batteries in external cabinets match the internal batteries in the NX in
manufacturer and type.
If using multiple sets of batteries connected in parallel to provide the required battery backup run
times, fit each set with an isolating device to permit working on one of the battery sets while leaving
the others in service and providing backup protection.
When replacing batteries, replace with the same manufacturer and type, or equivalent. See your Lie-
bert representative for a list approve batteries.
3.2 Safety
Special care should be taken when working with the batteries associated with the NX system equip-
ment. When all batteries are connected together, the battery terminal voltage may exceed 324V and is
POTENTIALLY LETHAL.
3.3 UPS Batteries
The NX's internal batteries are fully charged before the unit is shipped. During storage and transpor-
tation, some charge is lost. All batteries should be recharged before use. The battery charger works
only when the NX is connected to input power and turned On.
NOTE
The NX, as shipped, has 24 12-volt batteries installed internally in each unit.
!
WARNING
The NX's internal batteries are connected and energized even if the UPS is turned Off. To
minimize the risk of injury, a qualified service person should disconnect internal batteries
before any maintenance is performed on the unit.
The center of the battery is connected to the neutral of the UPS and is grounded.
A battery can present a risk of electrical shock and high short circuit current. The following
precautions should be observed when working on batteries:
• Remove watches, rings and other metal objects.
• Use tools with insulated handles.
• Wear rubber gloves and boots.
• Do not lay tools or metal parts on top of batteries.
• Disconnect charging source prior to connecting or disconnecting battery terminals.
NOTE
Full safety instructions concerning the use and maintenance of UPS batteries are provided in
the appropriate battery manufacturer's manuals, available on the manufacturer's Web site.
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 your installation.