Lenze 8615E - Manual (Page 40)

6 Accessories
Accessories are not included in the of supply.
6.1 resistors
In the generator mode, e.g. when decelerating the drive, the
returns energy to the DC bus of the controller. If large
inertias are braked and/or short deceleration times are set, the DC
bus voltage may exceed its maximum permissible value. In the
of overvoltage in the DC bus, the controller sets pulse inhibit
and indicates “overvoltage The controller cancels the pulse inhibit
once the votlage has returned to the permissible range.
To avoid overvoltage braking, a brake chopper is used,
switches an external brake resistor when the voltage in the
DC bus exceeds 765 V.
The absorbed energy is dissipated as heat so that the voltage in
the DC bus does not rise
l
The brake chopper is already included in the Standard
controller.
l
The suitable brake chopper is available as an Option. It is
connected to the terminals and BR2
(see connecting diagram, page 28).
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