Toshiba H9 - Manual (Page 132)

124 H9 ASD Installation and Operation Manual
Run Frequency Hysteresis
Program
⇒
Special
⇒
Frequency Control
This parameter provides a plus-or-minus value for the Run Frequency setting
(F241 ).
Direct Access Number — F242
Parameter Type — Numerical
Factory Default — 0.00
Changeable During Run — Yes
Minimum — 0.00
Maximum — 30.0
Units — Hz
End Frequency
Program
⇒
Special
⇒
Frequency Control
This parameter sets the lowest frequency that the drive will recognize during
deceleration before the drive goes to 0.0 Hz.
Direct Access Number — F243
Parameter Type — Numerical
Factory Default — 0.00
Changeable During Run — Yes
Minimum — 0.00
Maximum — 30.0
Units — Hz
0 Hz Dead Band Signal
Program
⇒
Special
⇒
Special Parameters
This parameter sets an output frequency threshold that, until the commanded
frequency surpasses this setting, the ASD will output 0 Hz to the motor.
This setting will override the Start Frequency setting ( F240 ) if this setting has
a higher value.
Direct Access Number — F244
Parameter Type — Numerical
Factory Default — 0.00
Changeable During Run — Yes
Minimum — 0.00
Maximum — 5.00
Units — Hz
DC Injection Braking Start Frequency
Program
⇒
Protection
⇒
DC Braking
During deceleration this is the frequency at which DC Injection braking will
start.
DC Injection Braking
DC Injection Braking is a braking system used with three-phase motors.
Unlike conventional brakes, there is no physical contact between the rotating
shaft and a stationary brake pad or drum. When braking is required, the drive
outputs a DC current that is applied to the windings of the motor to quickly
brake the motor. The braking current stops when the time entered in
F252 times
out.
The intensity of the DC current used while braking determines how fast the
motor will come to a stop and may be set at
F251 . The intensity setting is
entered as a percentage of the full load current of the ASD.
DC Injection Braking is also used to preheat the motor or to keep the rotor
from spinning freely when the motor is off by providing a pulsating DC current
into the motor at the Carrier Frequency. This feature may be enabled at
F254 .
Direct Access Number — F250
Parameter Type — Numerical
Factory Default — 0.00
Changeable During Run — Yes
Minimum — 0.00
Maximum — 120.00
Units — Hz
DC Injection Braking Current
Program
⇒
Protection
⇒
DC Braking
This parameter sets the percentage of the rated current of the drive that will be
used for DC Injection braking. A larger load will require a higher setting.
Direct Access Number — F251
Parameter Type — Numerical
Factory Default — 50
Changeable During Run — Yes
Minimum — 0
Maximum — 100
Units — %
F242 F251