Nidec DFS 1, Power Installation Manual

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DFS1/DFS2 Power Installation Guide
Issue Number: 2
4.21.3 Heatsink fan supply
When the drive is operated in low voltage mode, a 24 V supply needs to be provided for the heatsink
fan. This should be connected to terminals 61 and 62.
For further information see the Unidrive M700, M701, M702 Control User Guide. CT Part Number:
0478-0353-02.
4.21.4 Low voltage operation
With the addition of a 24 Vdc power supply to supply the control circuits, the drive can operate from a
low voltage DC supply with a range from 24 Vdc up to the maximum DC volts. It is possible for the
drive to go from operating on a normal line power supply voltage to operating on a much lower supply
voltage without interruption. Going from low voltage operation to normal mains operation requires the
inrush current to be controlled. This may be provided externally. If not, the drive supply can be
interrupted to utilise the normal soft starting method in the drive.
To fully exploit the low voltage mode of operation, the under-voltage level is user programmable.
For more information on how to use this feature, contact the supplier of the drive.
4.22 Electromagnetic compatibility
4.22.1 General requirements for EMC
Variable speed drives are powerful electronic circuits which can cause electromagnetic interference if
not installed correctly with careful attention to the layout of the wiring.
It is the responsibility of the installer to ensure that the equipment or system into which the product is
incorporated complies with the relevant EMC legislation.
Detailed information on EMC compliance is given in the DFS drive EMC Data Sheet, available from
the supplier of the drive, CT part number 0478-0575-01.
In the DFS drives, the drive module is mounted on a metal backplate which is safety bonded to the
power ground busbar in the enclosure. See Figure 4-7.
If used on a low-voltage public network which supplies domestic premises, then radio
frequency interference is to be expected.
CAUTION