Chapter 3 Electrical Installation 17
NX UPS Single Module And Parallel System 250kVA ~ 800kVA User Manual
Chapter 3 Electrical Installation
This chapter mainly introduces the electrical installation of the UPS, including the wiring of the power cables and
signal cables.
After completing the mechanical installation of the UPS, it is required to connect the power cables and control cables
of the UPS. All the control cables, whether shielded or not, shall be kept away from the power cables.
Warning: professional installation required
1. Do not apply electrical power to the UPS before being authorised to do so by the commissioning engineer.
2. The UPS shall be installed by authorized engineer in accordance with the information contained in this chapter.
3.1 Wiring Of Power Cable
3.1.1 System Configuration
The cable size of the system power cable shall meet the following requirement:
UPS input cable
Cable size of the UPS input cable differs with the UPS power ratings and input AC voltages, provided that it meets
the requirement of maximum input current, including the maximum battery charge current, as shown in Table 3-1.
UPS bypass and output cable
Cable size of the UPS bypass and output cable differs with the UPS power rating and output AC voltages, provided
that it meets the requirement of nominal output or bypass current, as shown in Table 3-1.
Battery cable
Each UPS connects to its battery through the positive, negative and neutral battery cables. The cable size of the
battery cable differs with the UPS power ratings, provided that it meets the battery discharge current requirement
when the battery discharges to near EOD voltage, as shown in Table 3-1.
Note: For 500kVA ~ 600kVA E UPS, the single-phase cable size is up to 3*300mm
2
.
3.1.2 Maximum Steady State AC And DC Currents
The power cable must be selected according to the current and voltage values in Table 3-1, the local wiring
regulations, the environmental conditions (temperature and physical media) and requirements in IEC60950-1
Table 3-B.
Table 3-1 Maximum steady state AC and DC currents
Rated current (A)
Busbar stud size
Output current
2
at
full load
Main input, output
and battery
terminals
Bypass input and
output terminals
UPS
rating
(kVA)
Max.
input
current
1
,
2
380V
400V
415V
Max. battery
discharge
current
(BAT+, BAT-)
Max. battery
discharge
current (BAT N)
Bolt
Torque
(N.m)
Bolt
Torque
(N.m)
800 1380 1212
1160
1112
1990
500
600 1168 910
870
834
1658
500
600 E
956
910
870
834
1064
400
500 896 758
725
694
997
400
400 690 606
580
556
995
250
300
584
455
435
417
829
250
300 E
459
455
435
417
670
250
250 431 379
363
348
628
250
M12 39 M12
39