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© Copyright 2021 ABB. All rights reserved.
NOTE:
The LINE and NEUTRAL of all shelves in a multiple
-
shelf system must be connected together
in an AC distribution panel or optional maintenance bypass panel (refer to J
-
Drawing 438827E
List number 51 and 52).
NOTE:
The inverter
’
s output protection will shutdown the inverter output after 5 seconds under
short circuit or deep overload conditions. Therefore, the response time of the breaker must
allow the breaker to trip within (4) seconds with a short circuit current of 28A per inverter.
Both the circuit breaker rating and number of inverters equipped in the system must be taken
into account to insure that the circuit breaker trips in the desired timeframe. If faster
response times are desired, e.g. below the AC holdup time of the AC equipment, then the trip
time must be decreased by lowering trip rating of the breaker, and/or increasing the number
of modules equipping the system.
Table 4 shows typical trip times of commercially available AC distribution circuit breakers. The table
lists
“
min
-
max
”
trip times based on most common circuit breaker ratings vs. number of equipped
−48
V inverters in the system. The maximum rating must be used to guarantee tripping within a
specific time. For special situations where commercial AC breakers do not meet the required trip
times, contact technical support for other options.
Table 4 Typical Trip Ratings for 10 –
30
Amp AC Circuit Breakers
Number
of
−48
V
Inverters
Avail.
Trip
Current
(A)
10 A Trip Time
(msec.)
15 A Trip Time
(msec.)
20 A Trip Time
(msec.)
25 A Trip Time
(msec.)
30 A Trip Time
(msec.)
Min
Max
Min
Max
Min
Max
Min
Max
Max
3
84
400
2000
700
3000
1250*
5000*
1700*
7000*
4500*
20000*
4
112
5
1300
5
1600
400
2800
900
3700
2250*
9000*
5
140
5
800
5
1100
5
1600
600
2500
1300*
5500*
6
168
5
700
5
800
5
900
400
1800
1000
4000
7
196
5
450
5
600
5
600
250
1300
600
2800
8
224
5
300
5
300
5
400
60
1000
475
2250
9
252
5
18
5
20.00
5
18
5
850
300
1700
10
280
5
17.5
5
18.00
5
17
5
700
200
1300
11
308
5
15
5
17.00
5
16.67
5
600
5
1200
12
336
5
16.67
5
16.67
5
16.67
5
500
5
1000
13
364
5
16.67
5
16.67
5
16.67
5
450
5
800
14
392
5
16.67
5
16.67
5
16.67
5
425
5
700
15
420
5
16.67
5
16.67
5
16.67
5
375
5
600
16
448
5
16.67
5
16.67
5
16.67
5
350
5
550
17
476
5
16.67
5
16.67
5
16.67
5
300
5
500
18
504
5
16.67
5
16.67
5
16.67
5
275
5
450
19
532
5
16.67
5
16.67
5
16.67
5
250
5
400
20
560
5
16.67
5
16.67
5
16.67
5
225
5
375
21
588
5
16.67
5
16.67
5
16.67
5
215
5
350
22
616
5
16.67
5
16.67
5
16.67
5
200
5
325
23
644
5
16.67
5
16.67
5
16.67
5
175
5
300
24
672
5
16.67
5
16.67
5
16.67
5
150
5
275
* Circuit breaker rating not recommended for this number of inverters equipped
Bas
ed
on
S
qu
ar
e
-
D
, QO
S
er
ies
