PowerWalker VFI 20000-40000TAP 3/3 BI, User Manual

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• The bypass feed into this equipment uses four wires (three line conductors and neutral conductor), plus
grounding conductor (protective earthing conductor) . The rectifier feed into this equipment uses four wires
(three line conductors and neutral conductor), plus grounding conductor (protective earthing conductor). The
phases must be symmetrical about ground (from a Wye/Star source) for proper equipment operation.
• Parallel UPS input wiring size requirements and output wiring size requirements from the UPSs to the Tie
Cabinet are the sames as those for single systems.
• Install a proper three-pole overcurrent disconnect device before connecting to the UPS, the disconnect
device shall disconnect simultaneously all line conductors of the AC MAINS SUPPLY.
• MBS (Maintenance bypass switch) is installed inside the UPS. When maintaining, open neutral switch and
MBS to isolation the UPS internal parts from the utility. Do not open neutral switch in any other cases
because the neutral is required for UPS operation. For some
VFI 60000-80000TAP 3/3 BX model without
internal neutral switch, external neutral switch shall be installed in site for maintenance.
• If a disconnect device interrupts the neutral conductor, it shall simultaneously interrupt all line conductors.
• When single-phase current exceeds 100A, switches of protective atmosphere should be equipped with
arc-control device.
• The UPS requires an input neutral connection. Ensure that an input neutral is connected prior to energising
the UPS. If a 4 pole Automatic Transfer Switch is installed upstream of the UPS it must work with a break
before make transition with a minimum transfer time of 50ms.
Figure 4-4 and Figure 4-5 show the location of the UPS power cable terminals.
L1 L2 L3 N
Input
Output
MBS
L1 L2 L3 N
Suggested
External Neutral
Switch for
Maintenance
Input switch Output switch
93E60-80K
Figure 3-11. VFI 60000-80000TAP 3/3 BX N Switch connection
(
Recommended
)