UPS Electrical Installation
9
Liebert
®
e
XL
™
The following are guidelines only and are superseded by local regulations and codes of practice where
applicable:
• The grounding conductor should be sized according to the fault rating, cable lengths, type of
protection, etc. The grounding cable connecting the UPS to the main ground system must follow
the most direct route possible.
• Consideration should be given to the use of paralleled smaller cables for heavy currents, as this
can ease installation considerably.
• AC and DC cables must be run in conduits according to local codes, national codes and standard
best practices. This will prevent creation of excess EMI fields.
2.3
Sizing the Input Breaker Feeding a Liebert
e
XL UPS
Nominal input current (considered continuous) is based on full-rated output load. Maximum current
includes nominal input current and maximum battery recharge current (considered noncontinuous).
Continuous and noncontinuous current are defined in the NEC.
Maximum input current is controlled by the current limit setting, which is adjustable. Values shown
are for default current limit of 125%. If a smaller input feed breaker is used, the input current limit
can be adjusted; see your Emerson representative for more information. The input current limit
should not be set less than 105% of the current needed to support the inverter at full load for normal
operation. This results in sufficient power to recharge the battery in a reasonable time and to operate
over the published input voltage range.
2.3.1 Power Cable Connection Procedure
The rectifier input, bypass, output and battery power cables (all require lug-type terminations) are
connected to busbars in the I/O sections (refer to
Equipment Ground
The equipment ground busbars are in the I/O sections (refer to
). The
grounding conductor must be connected to the ground busbar and bonded to each cabinet in the
system.
All cabinets and cabling should be grounded in accordance with local regulations.
Once the equipment has been positioned and secured, connect the power cables as described below
(refer to the appropriate cable connection drawing in
1. Verify that the UPS equipment is isolated from its external power source and all the UPS power
isolators are open. Check that these supplies are electrically isolated and post any necessary
warning signs to prevent their inadvertent operation.
NOTE
Proper grounding reduces problems in systems caused by electromagnetic interference.
!
WARNING
Failure to follow adequate grounding procedures can result in electric shock hazard to
personnel, or the risk of fire, should a ground fault occur.
All operations described in this section must be performed by properly trained and qualified
electricians or technical personnel. If any difficulties are encountered, contact Emerson
Network Power. See the back page of this manual for contact information.
!
AVERTISSEMENT
Le non-respect des procédures de mise à la terre peut entraîner des risques d’électrocution du
personnel, ou des risques d’incendie en cas de défectuosité de la mise à la terre.
Toutes les opérations décrites dans cette section ne doivent être effectuées que par des
électriciens ou des techniciens professionnels dûment formés et qualifiés . En cas de
difficultés, communiquez avec Emerson Network Power. Pour obtenir les renseignements de
contact, consultez la dernière page de ce manuel.
