Wiring Considerations; Power Wiring - Liebert Series 600T Installation Manual

8. WIRING CONSIDERATIONS

8.1. Power Wiring

Refer to Site Planning Data (Appendix A) and the
installation drawings. Determine AC currents for
your system based on kVA, kW, voltage, and
options. Also refer to equipment nameplate for the
model number, rating, and voltage. For wire
termination data, refer to Tables 1-3.
1. Power wiring -- rectifier input, bypass input,
UPS output, and battery cables -- must be run
in individual, separate conduit or cable tray.
Refer to the Outline and Terminal Details
drawings (Figures 11-13 and 35-39) for location
of the various power connections within the
UPS.
CAUTION
Power and control wiring must be
separated!
2. Observe local, state and national electrical
codes. Verify utility power and its overcurrent
protection rating will accommodate the UPS
input rating, including battery recharging.
3. A safety ground wire must be run from
building ground to ground point in the UPS
Module Cabinet, the Battery Cabinet and the
Power-Tie™ switchgear cabinet. See Sections
7.1 through 7.7. The grounding conductor shall
comply with the following conditions of
installation:
a. The insulated grounding conductor must be
sized in accordance with the NEC and local
codes. It must be green (with or without
yellow stripes) and be installed as part of
the branch circuit that supplies the unit or
system.
b. The grounding conductor described above is
to be grounded to earth at the service equip-
ment or, if supplied by a separately derived
system, at the supply transformer or motor-
generator set in accordance with the
instructions in Section 7 of this Manual.
c. The attachment-plug receptacles in the
vicinity of the unit or system are all to be of
a grounding type, and the grounding con-
ductors serving these receptacles are to be
Liebert Series 600T UPS, 65-225 kVA, Single Module
connected to earth ground at the service
equipment.
4. Observe clockwise phase rotation of all power
wiring. Phase A leads Phase B leads Phase C.
A qualified electrician should check the phase
rotation.
5. Power cables must be rated for less than 2 volts
line drop at maximum rated system current.
6. Use 75°C copper wire. Select wire size based on
the ampacities in Table 310-16 and associated
notes of the National Electrical Code (NFPA
70) reprinted on page 24 of this manual.
CAUTION
The weight of power cables must be
adequately supported to avoid stress on
bus bars and lugs. The following
restraining method is recommended to
both to support cable weight and control
cable movement during external fault
conditions: Wrap line cables together at 6
inches and 12 inches from the terminals
with 5 wraps of 3/8 inch nylon rope or
equivalent (tensile strength of 2000
pounds). Support remainder of cable with
5 wraps every 6 inches or 1 wrap every 1
inch.
7. If site equipment includes a backup generator
and automatic transfer switch(es), consult the
manufacturers of those devices for information
on sizing and interfacing to the UPS system.
8. The installing contractor can remove the access
plates from the top left or top right sides of the
UPS in order to cut entry holes for conduit. For
units with bottom-entry cable access, there is a
separate (third) access plate in the base of the
unit, under the cable access wireway.
CAUTION
After cutting holes in the access plates, be
certain that no foreign matter (metal
shavings, sawdust, insulation or wire
fragments, etc.) remains inside the UPS.
Likewise be certain to block any "extra"
holes in the plates through which foreign
matter could later enter the UPS.
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