Table 14: Selection of the Correct Pre-charging Unit
System modules
Pre-charging unit
IM10 + IM10 / IR10 + IR10
IM11 + IM11 / IR11 + IR11
2 x IM10 + 2 x IM10 / 2 x R10 + 2 x IR10
Pre-charging unit 10 (IEC or UL)
2 x IM11 + 2 x IM11 / 2 x IR11 + 2 x IR11
3 x IM11 + 3 x IM11 / 3 x IR11 + 3 x IR11
4 x IM11 + 4 x IM11 / 4 x IR11 + 4 x IR11
Pre-charging unit 20 (IEC or UL)
5 x IM11 + 5 x IM11 / 5 x IR11 + 5 x IR11
6 x IM11 + 6 x IM11 / 6 x IR11 + 6 x IR11
Pre-charging unit 30 (IEC or UL)
Table 15: Maximum Capacitance of the Pre-charging Unit
Pre-charging unit
Network [V AC]
Capacitance [μF]
400/500
66500
Pre-charging unit 10 (IEC or UL)
690
29500
400/500
184000
Pre-charging unit 20 (IEC or UL)
690
76500
400/500
275000
Pre-charging unit 30 (IEC or UL)
690
114500
There are thermal restrictions in a repeated use of the pre-charging unit. See the allowed pre-charging cycle in a 60 °C (140 °F) ambient
temperature in
Table 16: The Thermally Allowed Pre-charging Cycle
Step
Task
Duration
1.
Charging
10 s
2.
Discharging
50 s
3.
Charging
10 s
4.
Discharging
50 s
5.
Wait for the pre-charging unit to cool
down.
10 min
6.
Repeat
–
52
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Design Guide | iC7 Series Air-cooled System Modules