3 battery over current protection and wire sizing, Battery over current protection and wire sizing – GE Industrial Solutions SG Series 400 & 500 Installation Guide User Manual
Page 20
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
The AC values below are current ratings per phase.
These maximum and nominal ratings should be considered when choosing the appropriate AC
over current protection device.
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.
(See Fig. 3.7.1-1 and 3.7.1.2)
AC Input Rectifier
AC Input Bypass
AC Input
DC Input
F1
F3
UPS rating
Max.
F2
Nom.
Nom.
Max.
F4
SG Series 400
512 A
615 A
481 A
512 A
615 A
702 A
SG Series 500
617 A
708 A
600 A
617 A
708 A
960 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
AC Input Bypass
AC Input
DC Input
UPS rating
F1
F2
F3
F4
SG Series 400
800 A
700 A
800 A
1,000 A
SG Series 500
1,000 A
800 A
1,000 A
1,200 A
WIRING
Wire sizing according to
NEC Section 210-20 (A) Table 310-16
Use 167°F (75°C) copper wire
Wiring requirements:
AC INPUT RECTIFIER:
3-Phase, 3 wire plus Ground
AC INPUT BYPASS:
3-Phase, 4 wire plus Ground
AC OUTPUT:
3-Phase, 4 wire plus Ground
DC INPUT:
2 wire (positive and negative) plus Ground
Maximum recommended cable size
UPS rating
Rectifier Input
Bypass Input
DC Input
AC Output
GND
SG Series 400
SG Series 500
4x500 kcmil
4x500 kcmil
4x600 kcmil
4x500 kcmil
3x500 kcmil
Modifications reserved
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User Manual SG Series 400 & 500 UL S2