132 GX9 ASD Installation and Operation Manual
Dynamic Braking Selection
Program Protection Dynamic Braking
This parameter Enables/Disables the Dynamic Braking system.
Settings:
0 — Off
1 — On with Overload
Dynamic Braking uses the transistor IGBT7 to dissipate the bus voltage when
required.
Dynamic Braking
Dynamic Braking is used to prevent over-voltage faults during rapid
deceleration or constant speed run on cyclic overhauling applications.
Dynamic Braking dissipates regenerated energy in the form of heat. When
using a DBR use thermal protection.
The resistive load is connected across terminals PA and PB (non-polarized).
Using a low-value, high-wattage resistance as a load for the generated current,
the resistive load dissipates the induced energy.
Dynamic Braking helps to slow the load quickly; it cannot act as a holding
brake.
The Dynamic Braking function may be set up and enabled by connecting a
braking resistor from terminal PA to PB of the ASD and providing the proper
information at F304, F308, and F309.
See the section titled Dynamic Braking Resistor Requirements on pg. 6 for
more information on using the DBR system and for assistance in selecting the
appropriate resistor for a given application.
Direct Access Number — F304
Parameter Type — Selection List
Factory Default — (ASD-Dependent)
Changeable During Run — Yes
Over-Voltage Limit Operation
Program Protection Stall
This parameter enables the Over-Voltage Limit function. This feature is used
to set the upper DC bus voltage threshold that, once exceeded, will cause an
Over-Voltage Stall.
An Over-Voltage Stall increases the output frequency of the ASD during
deceleration for a specified time in an attempt to prevent an Over-Voltage Trip.
If the over-voltage threshold level setting of parameter F626 is exceeded for
over 4 mS, an Over-Voltage Trip will be incurred.
Parameter F452 (Power Running Stall Continuous Trip Detection Time) setting
may affect the performance of this parameter setting.
Note: This parameter setting may increase deceleration times.
Settings:
0 — Enabled (Over-voltage Stall)
1 — Disabled
2 — Enabled (Forced Shorted Deceleration)
Direct Access Number — F305
Parameter Type — Selection List
Factory Default — Enabled
Changeable During Run — Yes
F304 F305