Digital Equipment HA3000, Руководство по установке

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4–4 INSTALLATION
4.2.2 Bypass AC Input (MAINS2) Connection
The bypass ac input connection is three-phase, four-wire Wye
1
plus equipment ground.
The phase rotation must be A, B, C. Bypass ac input (MAINS2) voltage must match the
UPS output voltage. Refer to Table 4–1 for the nominal bypass ac input current at the
nominal bypass ac input voltage specified. Size the bypass ac input cables and upstream
protection devices accordingly.
CAUTION
Single-point grounding: The UPS cabinet is shipped from the factory with
the neutral bus tied to ground with a jumper that has a yellow tag attached
(Figure 4–2). If the UPS cabinet bypass ac input (MAINS2) source already
has the neutral grounded (either from the facility power source or from the
UPS Auxiliary Cabinet/CSA Cabinet isolation transformer), remove the jumper
between the neutral and ground busbars in the UPS cabinet. This prevents a
ground loop problem.
Proper grounding procedures are essential
to the operation of an Uninterruptible Power
System (UPS), personnel safety and critical
load equipment protection. The National
Electrical Code (NEC) and applicable local
codes must be followed. Please refer to
Installation Manual (EK-HA32X-IN)
for various load configurations and
recommended grounding schemes.
04-45063-38 NC
M K V - A 2 2 4 3 - 9 1
Figure 4–2 Yellow Jumper Tag
4.2.3 UPS Output Load Connection
The UPS output load connection is three-phase, four-wire Wye plus equipment ground.
Phase rotation is A, B, C. Refer to Table 4–1 for the unit ac output current rating at
the nominal output voltage specified. Size the output cables and downstream protective
devices accordingly.
NOTE
A three-wire Delta load can be connected to the UPS inverter output. This Delta
load cannot have any grounded phase connections.
4.2.4 Battery Connection
For each individual UPS Battery Cabinet three wires are required: positive (+), negative
(-), and ground from the UPS Battery Cabinet to the UPS cabinet. Refer to Table 4–1 for
the maximum battery current required for the unit specified. Battery cables should be
sized to keep the total cable voltage drop to less than 0.5 Vdc at the maximum current
specified.
1
The HA32A-Cx cabinet does not require a neutral conductor or a Wye power source. Three phase
wires plus equipment ground are required for these models.