Dc Input; Dc Input Circuit Breaker; Line To Neutral Inverter Receiver Junction Box; Line To Neutral Units Suggested Dc Circuit Breaker Ratings - MGE UPS Systems 3.5 to 21 kVA N+1 Owner's Manual

2.5.2 DC Input

Normal: -48VDC
Operating Range: -39.5 VDC to -57VDC
This system is designed for battery systems with the positive terminal Earth Ground. All DC breakers are
in the negative DC lines. The system DC terminals are isolated from Earth Ground.
2.5.3

DC Input Circuit Breaker

Due to tremendous amounts of short circuit current available (in excess of 1000A for as long as several minutes!)
from bank(s) of batteries, that supply electrical power to inverter systems, it is extremely important to connect a
properly sized DC circuit breaker at the DC input cable that feeds the inverter system. The following table is pro-
vided as a guide for selecting the proper circuit breaker.
Table 2-2: Line To Neutral Units Suggested DC Circuit Breaker Ratings.
Inverter rating
CB rating
Figure 2-3: Line To Neutral Inverter Receiver Junction Box.
GND
N-IN
N-OUT
TB1
L-OUT
L-IN
INVERTER RECEIVER
WITH JUNCTION BOX
7 kVA
200A
JUNCTION
BATTERY
BATTERY
BACK VIEW
Installation & Operation - Line to Neutral
14 kVA
400A
BOX
(-)
(+)
INVERTER RECEIVER
WITH JUNCTION BOX
Owner's Manual
21 kVA
600A
SIDE VIEW
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