Powering The Ac Fan In Frame G - ABB ACS850 Application Manual

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DC voltage control: the overvoltage and undervoltage control of the DC link voltage
•
level are enabled by default. Then the drive modules will limit the motoring and
generating torque, if there is a need to keep the DC link voltage within the control
limits. In common DC configurations with enabled braking chopper, the over voltage
control mode should be disabled. See voltage control parameters in group 47.
DC overvoltage and undervoltage trip limit: these limit values protect the drive
•
modules. The drive module trips and gives a fault message if the DC link voltage
reaches these levels.
Braking chopper limits: the braking chopper in the drive module is activated (if the
•
braking chopper is enabled) when the DC link voltage reaches the low level
(U
braking chopper feeds the braking resistor with continuous current and the
maximum braking power level is reached.

Powering the AC fan in frame G

If the supply of frame size G is not connected to the main supply, the AC fan must be
powered separately. Feed the primary of the fan circuit transformer with the converter's
nominal main supply voltage, V- and W-phases, via the built-in fan circuit. The original
cables between the busbars and the fuses have to be removed. The feeding cable
must be protected against short circuits despite of the used built-in fuses. The fuse
location is shown in the following picture.
Common DC configurations
). If the DC link voltage level reaches the high level (U
D C, brcl
), then the
DC,brch