Non-regenerative front end
vacon • 189
Local contacts: http://drives.danfoss.com/danfoss-drives/local-contacts/
11
The Non-regenerative Front End unit must not be connected to mains without pre-charging. In order
to ensure the correct operation of the pre-charging circuit, the input circuit-breaker and the pre-
charging circuit contactor must be controlled by the Non-regenerative Front End unit. The input
circuit-breaker and the pre-charging circuit contactor must be connected as shown in
Chapter 11.2.1.
NOTE!
You need to double-insulate all wirings that do not have short circuit protections and are
used for connecting the pre-charging circuit to the intermediate circuit.
NOTE!
Enough space must be reserved around the resistors to ensure sufficient cooling. Do not
place any heat sensitive components near the resistors.
11.12
Paralleling
The power of the input group can be increased by connecting several Non-Regenerative Front End
units in parallel. Manufacturer's standard chokes must be used for parallel units. Use of other than
these chokes in the Non-Regenerative Front End units connected in parallel may cause a too large
current imbalance between the units.
Each Non-Regenerative Front End unit connected in parallel must have its own short-circuit
protection on AC and DC sides and own circuit breakers in AC side. When paralleling, attention must
be paid to the sufficient short-circuit capacity of the system.
The derating of Non-Regenerative Front End units connected in parallel is 10% of the DC power; this
should be taken into account when dimensioning the system.
If a device is to be isolated from the AC and DC voltages, and other Non-Regenerative Front End
units connected in parallel are also to be used, separate isolators are required in the AC input and
DC output. The AC input can be isolated using a circuit-breaker or a fuse switch. Contactors are not
suitable for isolating the AC input because they cannot be locked in a safe position. The DC output
can be isolated using a proper load switch. The pre-charging circuit must also be isolated from the
AC input by using fuse switch. The device can also be connected to mains even when the other
devices connected in parallel are already connected and running. In such a case, the isolated device
must first be pre-charged. When that is done, the AC input can be switched on. After this, the device
can be connected to the intermediate DC circuit.
FI13 AFE / CHARGING-AFE-FFE-FI13
Item
Q‘ty
Description
Manufacturer
Product Code
1
1
Diode Bridge
Semikron
SKD 82
2
2
Charcing resistors
Danotherm
CBV335C11R
3
1
Snubber capacitor
Rifa
PHE448
4
1
Contactor
Telemecanique
LC1D32P7
Содержание NX
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