F304, Dynamic braking, On pg. 136 – Toshiba H9 User Manual
Page 144: F305
136
H9 ASD Installation and Operation Manual
Dynamic Braking
Program
⇒
Protection
⇒
Dynamic Braking
This parameter Enables/Disables the Dynamic Braking system.
Settings:
0 — Off
1 — On with Overload Detection
2 — On without Overload Detection
Dynamic Braking uses the transistor IGBT7 to dissipate the bus voltage when
required.
IGBT7 is a standard item on the 25 HP and below H9 ASD 230-volt systems
and is standard on the 400 HP and below for the for the 460-volt systems.
IGBT7 is optional for all remaining systems.
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 setup and enabled by connecting a
braking resistor from terminal PA to PB of the drive and providing the proper
information at
,
, and
.
See the section titled
Dynamic Braking Resistor Wire/Cable Specifications on
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 — Off
Changeable During Run — No
Overvoltage Limit Operation
Program
⇒
Protection
⇒
Stall
This parameter enables the Overvoltage Limit function. This feature is used to
set the upper DC bus voltage threshold that, once exceeded, will cause an
Overvoltage Stall.
An Overvoltage Stall increases the output frequency of the drive during
deceleration for a specified time in an attempt to prevent an Overvoltage Trip.
If the overvoltage threshold level setting of parameter
is exceeded for
over 4 mS, an Overvoltage Trip will be incurred.
Note:
This parameter setting may increase deceleration times.
Settings:
0 — Enabled (Overvoltage Stall)
1 — Disabled
2 — Enabled (Forced Shorted Deceleration)
3 — Enabled (Forced Dynamic Braking Deceleration)
Direct Access Number — F305
Parameter Type — Selection List
Factory Default — (ASD-dependent)
Changeable During Run — Yes