Liebert NX 10kVA, Руководство по установке

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5.5 Parallel System Startup
1. Start each UPS normally as described in the Liebert NX installation manual. SL-25215.
2. Turn on the inverter of each UPS module one at a time.
3. Apply the load after the last UPS module transfers to inverter. The total load can be determined
through the LCD of either UPS.
4. Verify the load rate of each UPS module. If the load rates are roughly the same, then the parallel
system may be assumed to be operating normally.
5.5.1 Emergency Power Off (EPO)
The external emergency stop facility is identical to that described for the single unit installation —
that an individual emergency stop button is provided for each unit. Note that this is a Normally Open
switch.
Figure 21 Connecting EPO push button
5.6 Battery Circuit Breaker Box
The box contains the same battery isolating circuit breaker as mounted in the battery cabinet.
Two battery circuit breaker boxes are available for use in installations where the battery is not
installed in the battery cabinet, in which case the appropriate battery box is fitted as close as possible
to the battery and connected to the UPS equipment as illustrated in Figure 22 .
The battery circuit breaker box, is required to protect the battery from overcurrents. It also provides
electrical isolation between the UPS and the battery, permitting technical service personnel to reduce
the risks involved in maintenance work to a minimum.
A separate safety earth must be connected between the UPS unit and circuit breaker box.
NOTE
If one module cannot transfer to inverter mode long after its inverter is on, its output
connection may not be good or its output phase rotation may not be coincident with other
modules. At this time, the LCD for the UPS module will display “inverter asynchronous” and
the inverter indicator will flash continuously. If either UPS module makes abnormal noise
after it transfers to inverter, its parallel cables may be incorrectly connected.
EPO-H
EPO
Monitor board
EPO-L
X2
UPS1
UPS2
EPO-H
Monitor board
EPO-L
X2