Chapter4
Electrical Installation 21
Liebert. PEX+Series Precision Air Conditioner User Manual
Chapter 4 Electrical Installation
Start electrical installation after mechanical installation is done. This chapter introduces the electrical installation of the
Liebert.PEX+ AC, including installation notes, and the wiring of indoor unit, and condenser power cables.
4.1 Installation Notes
1. The connection of all power cables, control cables and ground cables should comply with the local and national
electrician regulations.
2. The electrical installation and maintenance must be performed by authorized professional installation personnel.
3. See the unit nameplate for the full load current.
The cable sizes should meet the local wiring rules.
4. Mains supply requirement: 380Vac (-10% to +15%), 50Hz, 3N~
5. If the soft power cable uses Y-connection, and if the cable is damaged, it must be replaced by professional service
personnel.
6. Before the wiring, use a voltmeter to measure the power supply voltage and make sure that the power supply has
been switched off.
7. The applicable grid for this air conditioner: TN, TT star connection power system; consult Emerson for other
connections.
8. A breaking device shall be provided to be disconnected from power supply.
4.2 Wiring Of Indoor Unit
4.2.1 Locating Electrical Ports Of Indoor Unit
The locations of the low voltage devices are visible after the front door of the electrical control box of the indoor unit is
opened, as shown in Figure 4-1.The distribution information of the detailed low voltage components shall be
differentiated according to the labels.
Figure 4-1 Electrical control box
4.2.2 Connecting Power Cable Of Indoor Unit
The power connectors are located as shown in Figure 4-1. The enlarged view of power connector is as shown in
Figure 4-2, connect terminals L1 ~ L3, N, and PE respectively to their counterparts of external power supply. Reserve
some redundancy of the incoming cable and fix the cable to the cable clamp located on the inner side panel of the unit,
see Figure 4-1. For the cable specification, see the rated full load ampere (FLA) listed in Table 4-1.