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System Design
3.3 Model Selection
Starter sizing
The soft starter must be the correct size for the motor and the application.
Select a soft starter that has a current rating at least equal to the motor's full load current
(nameplate) rating, at the start duty.
The soft starter's current rating determines the maximum motor size it can be used with.
The rating depends on the number of starts per hour, the length and current level of the
start, and the amount of time the soft starter will be off (not passing current) between starts.
The soft starter's current rating is only valid when used in the conditions specified in the
AC53 code. The current rating may be higher or lower in different operating conditions.
3.4 Current Ratings
Contact your local supplier for ratings under operating conditions not covered by these
ratings charts.
IEC ratings
•
AC53b format (bypassed current rating)
80 A : AC-53b
3.5 - 15 : 345
Off time (seconds)
Start time (seconds)
Start current (multiple of motor full load
current)
Starter current rating (amperes)
•
Ratings
All ratings are calculated at altitude of 1000 metres and ambient temperature of 40 ºC.
3.0-10:350
3.5-15:345
4.0-10:350
4.0-20:340
5.0-5:355
0024B
24
20
19
16
17
0042B
42
34
34
27
32
0052B
52
42
39
35
34
3.0-10:590
3.5-15:585
4.0-10:590
4.0-20:580
5.0-5:595
0064B
64
63
60
51
54
0069B
69
69
69
62
65
0105B
105
86
84
69
77
0115B
115
108
105
86
95
0135B
135
129
126
103
115
0184B
184
144
139
116
127
0200B
200
171
165
138
150
0229B
229
194
187
157
170
0250B
250
244
230
200
202
0352B
352
287
277
234
258
0397B
397
323
311
263
289
0410B
410
410
410
380
400
0550B
550
527
506
427
464
0580B
580
579
555
470
508
8