Vertiv Liebert EXS 80kVA UPS, User Manual

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Vertiv™ Liebert EXS 80kVA UPS User Manual
6 Parallel System and LBS System
6.3.3. Power Cables
The power cable wiring is similar to that of the UPS module. Refer to 3.1 Wiring of Power Cable .
The bypass and rectifier input supplies must use the same neutral line input terminal. If the input has a
current leakage protective device, the current leakage protective device must be fitted upstream of the
neutral line input terminal.
NOTE: 1. The power cables (including the bypass input cables and UPS output cables) of each UPS
module should be of the same length and specifications to facilitate load sharing.
2. The UPS adopts common input configuration and split bypass configuration. If the mains input and
bypass input come from two different transformers, then these two transformers should share one
grounding grid.
6.3.4. Parallel Cables
Shielded and double-insulated parallel cables available in lengths 5m, 10m and 15m must be
interconnected in a ring configuration between the UPS modules, as shown in Figure 6-2. Method: connect
a single module parallel cable from its PARALLEL1 port to the PARALLEL2 port of another module. Repeat
this step for all the other parallel cables.
The ring connection ensures the reliability of the control of the parallel system. Be sure to verify that the
cables are connected securely before starting up the system!
Figure 6-2 Parallel cables connection
6.3.5. Remote EPO
In addition to the EPO terminal provided from each UPS module for controlling the EPO of each module
respectively, the parallel system also provides remote EPO function for controlling all UPS modules to shut
down simultaneously from a remote terminal, as shown in Figure 6-3.
NOTE: 1. The remote EPO switch must provide dry contact signal, which is normally open or normally
closed.
2. The external EPO device can be composed of another control system which can disconnect UPS
mains supply or bypass input.