Emerson Liebert APM 120, Manual

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Electrical Connections—UPS
Liebert
®
APM
™
18
3.2.5 UPS Input Configuration with Transformers
Figure 5 shows the Liebert APM in a split bypass (single-source, dual-input) configuration using two
transformers. One transformer is inside the Bypass Distribution Cabinet and the other inside the
UPS.
In this configuration, the static bypass and the maintenance bypass lines are supplied by the same
source using separate feeds. Both feeds must be protected externally with properly sized protective
devices.
Figure 6 shows the control wiring for the dual input transformer configuration.
Figure 5 Liebert APM in a split bypass configuration
AC Output
208V
4 Wire + GRD
* Rectifier
AC Input
4 Wire + GRD
See Note 7
* Bypass
AC Input
4-Wire + GRD
Bypass Distribution Cabinet
(Optional)
54 Pole
See Note 6
MIB BIB
MBB
Static Bypass
UPS Cabinet
Battery
UAM01024
Rev. 0
NOTES:
1. Install in accordance with national and local electrical codes.
2. Input and bypass must share the same single source.
3. A neutral is required from the system AC input source. A full
capacity neutral conductor is recommended. Grounding
conductors are recommended.
4. Bypass and rectifier inputs and output cables must be run in
separate conduits.
5. Control wiring must be run in separate conduits.
6. Optional 54 pole, 225A for 45kVA frame only or
optional 54 pole 400A for 90kVA frame only.
7. Customer must supply shunt trip breaker with 120V coil.
8. Input voltage options of the isolation
transformer: 600V, 480V, 220V and 208V.
BIB - Bypass Isolation Breaker
MBB - Maintenance Bypass Breaker
MIB - Maintenance Isolation Breaker Field-Supplied Wiring * External Overcurrent
Protection by Others