Danfoss Vacon NXP Applications Manual page 17

General
- To enable a zero power connection to an existing grid.
- To help in the commissioning of drive active power and reactive power voltage losses
compensation when the actual grid voltage is visible in NCDrive.
The OPT-D7 board is delivered with the transformer which is suitable for a voltage range up to 690
Vac. The transformer cannot be used with a pulse width modulated (PWM) voltage input.
It is possible to use a customised transformer when the input voltage to be measured is not within
the OPT-D7 transformer voltage range. The transformation ratio parameter can be adjusted
according to the transformer primary to secondary ratio. See details in the OPT-D7 user manual.
Synchronisation to the grid can be made without the OPT-D7 when the drive operates in the AFE or
the Micro Grid mode. This requires that the output terminals of the drive are connected to the
existing grid when the drive is in the STOP state. When a start command has been given in AFE or
Micro Grid mode, the drive will make standard AFE synchronisation. Depending on the operation
mode, the drive will start to keep constant DC voltage (AFE) or start to share power based on grid
frequency (Micro Grid). Using OPT-D7 for synchronisation will make the start of the drive smoother.
If the drive does not detect an existing line voltage or frequency in Micro Grid mode, the output
voltage is raised defined time (VoltageRiseTime). In the Island mode, the detection of the grid is not
made and the voltage is raised from zero in the set time (VoltageRiseTime).
NOTE: The OPT-D7 board (in slot C) is mandatory for the Grid Converter unit.
24-hour support: +358 (0)201 212 575 • Email: vacon@vacon.com
vacon · 15
1