Mechanical Installation
Vertiv
| Liebert
®
EXM
™
Parallel Cabinet User Manual |
13
Notes
Refer to the Liebert EXM UPS installation manual, SL-25648, SL-25650 or SL-26100 for additional
details about the Liebert EXM 10-40kVA, 60-100kVA and 120-200kVA UPS’s. The manual is
available at the Liebert Web site:
The following are guidelines only and are superseded by local regulations and codes of practice
where applicable.
• Take special care when determining the size of the neutral cable because current circulating on the neutral
cable may be greater than nominal current in the case of non-linear loads.
• The ground conductor should be sized according to local or NEC codes, cable lengths, type of protection,
etc. The ground cable connecting the UPS to the main ground system must follow the most direct route
possible.
• Consideration should be given to the use of smaller, paralleled cables for heavy currents, as a way to ease
installation.
• In most installations, the load is connected to a distribution network of individually protected busbars fed
by the Liebert EXM Parallel Cabinet output rather than being connected directly to the Liebert
EXM
Parallel Cabinet itself. Where this is the case, the Liebert EXM Parallel Cabinet output cables can be rated
to suit the individual distribution network demands rather than being fully load-rated.
• To avoid increasing formation of electromagnetic interference, do not form coils when laying the power
cables.
Table 3
Control wiring for Liebert EXM UPS to Liebert EXM Parallel Cabinet with SKRU interlock
System Configuration
From Liebert EXM UPS Bypass Module
TB7
2+1
1+1 & 2+0
UPS1
X9J23-4
TB7-1
X9J23-6
TB7-2
UPS2
X9J23-4
TB7-3
X9J23-6
TB7-4
2+1
UPS3
X9J23-4
TB7-5
X9J23-6
TB7-6
