Modifications reserved
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OPM_SGS_ISG_M75_M75_2US_V010.doc
Installation Guide
SG Series 750 UL S2
&
SG Series 750 T12 UL S2
3.8.3 Battery over current protection and wire sizing
•
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.
•
If the UPS system has been purchased with an accompanying
Battery Cabinet
, that cabinet should
have an integral
Battery Circuit Breaker
.
•
If the UPS has been purchased without a
Battery Cabinet
or 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 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. 3.8.1-1
and
3.8.1.2
)
AC Input
Rectifier (A)
AC Input
Bypass (A)
AC Input
(A)
DC Input
(A)*
F1
F3
F4
Nom. Max.
F2
Nom. Max. Nom.
Max.
SG Series 750 (6 pulse) with 5
th
filter
920 1103 902 902 1103
1512
1793
SG Series 750 (6 pulse) with 5
th
& 11
th
filter
900 1080 902 902 1080
1512
1793
SG Series 750 T12 (12 pulse) without filter
1082 1306 902 1082 1306 1512
1793
SG Series 750 T12 (12 pulse) with 11
th
filter
1032 1245 902 1032 1245 1512
1793
*)
DC over current sized to support maximum DC current.
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 (A)**
AC Input
Bypass (A)**
AC Input
(A)**
DC Input
(A)
F1
F2
F3
F4
SG Series 750 (6 pulse) with 5
th
filter
1200 A
1000 A
1200 A
2000 A
SG Series 750 (6 pulse) with 5
th
& 11
th
filter
1200 A
1000 A
1200 A
2000 A
SG Series 750 T12 (12 pulse) without filter
1600 A
1000 A
1600 A
2000 A
SG Series 750 T12 (12 pulse) with 11
th
filter
1600 A
1000 A
1600 A
2000 A
**)
Assumes 100% rated Circuit Breakers. Verify size for application of 80% rated devices.
WIRING
Wire sizing according to
NEC Section 210-20 (a) Table 310-16
Use 75°C (167°F) 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 750
SG Series 750 T12
5 x 500 MCM
4 x 500 MCM
6 x 600 MCM
4 x 500 MCM
4 x 500 MCM