Vacon NX series, Руководство пользователя

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Active Front End (AFE) vacon • 49
Local contacts: http://drives.danfoss.com/danfoss-drives/local-contacts/
4
4.15.2 Each Active Front End unit has the pre-charging circuit
Each Active Front End can have its own pre-charging circuit. Each unit controls its own pre-charging
and main contactor. See Figure 20. One control switch can be used, but if an Active Front End unit
needs to be controlled independently, separate switches are needed. With this the system is more
redundant than with a common pre-charging circuit. The circuit diagram for control, see Appendix
74 and Appendix 76.
Figure 20. Active Front End units parallel connection with own pre-charging circuits
PE
+LCL-U1
+LCL-U2
11166.emf
+AFE-U1
NXA xxxx x
+AFE-U2
NXA xxxx x
DC+
DC-
Main Circuit
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