Connecting The Ups Power Cables; Cable Entry; Cable Rating - Liebert 7400 Series User Manual

Chapter 3 - Installation Procedure
Battery Installation

Connecting the UPS power cables

3.4
3.4.1

Cable entry

by-side.
3.4.2

Cable rating

UPS NOMINAL CURRENT (Amps)
RATING
Input Mains
(kVA)
(with full battery recharge)
380V
6 Pulse
80 167
120 251
200 412
300 609
400 808
3-16
Issue 2
(02/98)
6310018a.02.doc
Before cabling-up the UPS, ensure that you are aware of the location and operation of
the external isolators that connect the UPS input/bypass supply to the mains
Check that these supplies are electrically isolated, and post any necessary warning signs
Cables can enter the smaller UPS modules and battery cabinet either
from below or through either side. Side entry is made possible by
removing blanking pieces fitted in the side ventilation grills to reveal the
cable entry holes. This cable entry method allows the equipment to be
positioned on a solid floor without the need for cable trenching and also
allows cables to pass from one module to the other when positioned side-
On units up to 200kVA normal cable entry is from the bottom, however,
if top entry is necessary, the optional top entry kit Pt.No. 2174011 Vfor
80 and 120kVA or Pt. No. 2174033 R for 200kVA is required. On the
300/400kVA unit cable entry is from the bottom or top of the unit.
The maximum current ratings for the power cables are given in table 3-1.
The neutral cable (bypass and output) should be sized at up to 1.5 times
the phase current to take into account the possible presence of 3rd
armonic currents due to single phase "computer loads".
In a one-plus-one Non-Redundant system, the lenght of the cables on the
Bypass line of the two UPS's should be equal (+/- 20%) to ensure the
balance of the currents, when the load is supplied by the mains.
Bypass/output
380V
12 Pulse
158 121
237 182
390 304
579 442
769 608
Table 3-1 - Nominal current for power cables
When sizing battery cables, a maximum volt drop of 3V d.c. is
permissible at the urrent ratings given in table 3-1.
Single Module and One plus One Systems
WARNING
distribution panel.
to prevent their inadvertent operation.
CABLE CONNECTION
Battery Input/output
(at low battery
disconnect)
Terminations
U - V - W - N
216 Secure with M8 Bolt
322 Secure with M10 Bolt
534 Secure with M10 Bolt
791 Secure with M12 Bolt
1053 Secure with M12 Bolt
7400 Series UPS User Manual
MAXIMUM SIZE
Battery
Cable
Termin-
ations
+ve & -ve
M8 Bolt
M10 Bolt
M10 Bolt
M12 Bolt
M12 Bolt