Battery Over Current Protection And Wire Sizing - GE SG 400 Series Installation Manual

3.7.3 Battery over current protection and wire sizing

NOTE !
•
Please read the safety precautions at the front of this guide carefully, and
thoroughly review the battery manufacturers installation and maintenance
manual before connecting the batteries to the UPS.
•
The remote rack mounted batteries are to be used then DC over current
protection must be provided by others.
•
Choose an appropriate DC fuse or circuit breaker using the current data in the
chart below.
•
Minimum battery cable requirement is based on the current data below.
•
The maximum available fault current from the battery supply is: 20kA.
•
The minimum breaker voltage rating is 540V
These maximum and nominal ratings should be considered when choosing the appropriate AC
NEC (National Electric Code) Section 210-20 (A) rules must be applied.
DC current rating is the nominal battery discharge current which the UPS allows.
UPS rating
Nom.
SG Series 400 512 A
SG Series 500
617 A
Size of Branch Circuit Over Current Protection - All Models: - "CAUTION - To reduce the risk of fire,
only connect UPS to a circuit provided with (See below) maximum amperes branch circuit over
current protection in accordance with the NEC (National Electric Code), NSI / NFPA 70
AC Input Rectifier
UPS rating
SG Series 400
SG Series 500
UPS rating Rectifier Input
SG Series 400
4x500 kcmil
SG Series 500
Modifications reserved
OPM_SGS_ISG_M40_M50_2US_V021.doc
The AC values below are current ratings per phase.
over current protection device.
(See Fig. 3.7.1-1 and 3.7.1.2)
AC Input Rectifier
F1
Max.
615 A
708 A
AC Input Bypass
F1
800 A
1,000 A
Wire sizing according to
NEC Section 210-20 (A)
Use 167°F (75°C) copper wire
Wiring requirements:
AC INPUT RECTIFIER:
AC INPUT BYPASS:
AC OUTPUT:
DC INPUT:
Maximum recommended cable size
Bypass Input
4x500 kcmil
AC Input Bypass
F2
Nom.
481 A 512 A
600 A 617 A
AC Input
F2
700 A 800 A
800 A 1,000 A
WIRING
Table 310-16
3-Phase, 3 wire plus Ground
3-Phase, 4 wire plus Ground
3-Phase, 4 wire plus Ground
2 wire (positive and negative) plus Ground
DC Input
4x600 kcmil
AC Input
F3
Max.
615 A
708 A
DC Input
F3 F4
1,000 A
1,200 A
AC Output
4x500 kcmil 3x500 kcmil
User Manual SG Series 400 & 500 UL S2
DC Input
F4
702 A
960 A
GND
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