Electrical Connections
2.0ELECTRICAL CONNECTIONS
The UPS requires both power and control cabling once it has been mechanically installed. All control cables must run separate from power cables in metal conduits or metal ducts that are electrically bonded to the metalwork of the cabinets to which they are connected.
! WARNING
Before connecting input power to the NX, ensure that you are aware of the location and operation of the overcurrent protection devices that connect the UPS input/bypass supply to the power distribution panel.
2.1Power Cabling
2.1.1Cable Rating
The main factors affecting the choice and size of cable are voltage, current (also taking into account overcurrent), room temperature and conditions of installation of the cable.
The power cables of the system must be sized with respect to the following description:
•UPS input cables - The UPS input cables must be sized for the maximum input current, includ- ing the maximum battery recharge current, given in Table 10, with respect to the unit rating and the input AC voltage.
•UPS bypass and output cables - The bypass and output cables must be sized for the nominal output current, given in Table 10, with respect to the unit rating and the output AC voltage.
•Battery cables - Each UPS unit has its own internal batteries
NOTE
Table 10 gives nominal currents for determining the size of UPS power cables. Other important factors to consider include cable route length and coordination with protective devices.
The power cables can be sized to suit the UPS unit rating according to Table 10.
Lug Size and Torque Requirements
Refer to Table 27 for lug size and torque requirements.
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