Toshiba TOSVERT VF-S11 Instruction Manual page 149

* The following parameters enables you to make adjustments more finely.
Title Function
Exciting current coefficient
Stall prevention control
coefficient 1
Stall prevention control
coefficient 2
Motor adjustment coefficient
Maximam voltage adjustment
coefficient
Waveform switching
adjustment coefficient
f480: Used to fine adjust the magnetic field increase rate in low-speed range. To increase the torque in
low-speed range, specify a larger value for
only when enough torque cannot be obtained, even though auto-tuning (
after the setting of the parameters
parameter may cause an increase in the no-load current in low-speed range. If the no-load current
exceeds the rated current, do not adjust this parameter.
: Using this parameter along with f492 adjusts characteristics in a region in which the frequency
is above the base frequency (region where the field is weak).
: Using this parameter along with f485 adjusts characteristics in a region in which the frequency
is above the base frequency (region where the field is weak).
* How to make adjustments in a region (region where magnetic field is weak) above the base
frequency
If a heavy load is applied instantaneously (or transiently), the motor may stall before the load
current reaches the current set with the stall prevention level 1 parameter (f601). In many
cases, this kind of stall can be avoided by gradually reducing the setting of f485.
A drop in supply voltage may cause fluctuations of the load current or vibration of the motor. In
some cases, such phenomena can be eliminated by changing the setting of f492 to between
80 and 90. However, this may cause an increase in load current, so that it is also necessary to
adjust the setting of the electronic thermal protective level 1 parameter (thr) properly
according to the motor capacity.
: There is no need to adjust this parameter under normal conditions. (Do not change the setting,
unless otherwise instructed by Toshiba technical staff)
: Specify a larger value for f495 to secure as high an output voltage as possible in a region
(region where magnetic field is weak) above the base frequency. Setting f495 to a larger value
may cause the motor to vibrate or gears to squeak. If such a phenomenon occurs, do not adjust
this parameter.
: Specify a larger value for f496 if switching from a waveform to another results in a considerable
increase in vibration and noise in middle-speed range (region between the start frequency and the
base frequency). If no improvement can be made by specifying a larger value, do not adjust this
parameter.
Adjustment range
100-130 (%)
10-250
50-150
0-200
90-110 (%)
0.1-14.0(kHz)
. Note that this parameter should be adjusted
through . Note also that adjusting this
F-55
E6581158
Default setting
100
100
100
Depends on
the capacity
104
0.2
= ) was made
6