Toshiba VF-SX - Manual (Page 127)

12-6
TOSHIBA
12.4 PWM Carrier Frequency [ C F ] and
Motor Tone Selection
[C F 5]
The acoustic noise of the motor changes when the PWM carrier frequency is
changed. Changing the PWM carrier frequency Is usually effective in quieting
the mechanical vibration noise when a resonation occurs at the load machine motor
fan cover. Other system characteristics are also affected by the carrier
frequency.
The PWM carrier can be set between 0.5 kHZ and 3 kHZ.
Motor noise can also be changed by selecting "integral tone" as an option from
the motor tone selection table.
TABLE 12-1; MOTOR TONE PARAMETERS
[ C F 5
] Value
Function
0
Monotonous tone
1
Integral tone
The motor tone parameter
[C F 5
] cannot be changed until the drive has NQI£i
been stopped.
12.5 Output Voltage Adjustment [ P O U b ] and
Power Voltage Compensation Function [ P R d J ]
The V/f characteristics can be set for a motor with a lower rated voltage by
using the output voltage reduction function. When the power voltage compensation
function is used , the output V/f characteristics are automatically compensated
to be constant even when the power voltage changes, so that the best V/f control
is possible at all times. However, an output voltage value greater than the
power voltage input value is not possible. This function is suitable for
machinery requiring a large start-up torque.
1. Output Voltage Reduction Function [
P O U b ]
The output voltage can be reduced proportionally to the input voltage.
The output voltage can be set between 0 and 100%.
2. Power Voltage Compensation Function [
P R d J ]
If this parameter is set to / the absolute value of the output voltage
can be set between 0 and 12056.