Vacon 50X, Руководство пользователя

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vacon 50x parameters vacon 72
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Parameter 502, Voltage Boost, increases the motor voltage at low speed to increase the
starting torque of the motor. The parameter sets the amount of boost (expressed as a
percentage of the default boost) to be applied at zero frequency. The amount of boost de-
creases linearly with increasing speed.
This parameter is used when parameter 501 is set with fixed boost options. For vector
mode this parameter is inactive.
This parameter sets the point on the frequency scale of the V/Hz curve at which the output
is at full line voltage. Normally, this is set at the base frequency of the motor, but it may
be increased to enlarge the constant torque range on special motors. Setting this param-
eter to a higher value can reduce motor losses at low frequencies.
To reduce mechanical resonances in a drive system, the drive may be configured to
“skip” certain frequencies. Once configured, the drive will accelerate or decelerate
through the prohibited frequency band without settling on any frequency in the band.
The Vacon 50X AC drive provides the capability to configure four prohibited frequency
bands. Parameter 504 (Skip Freq Band), the Skip Frequency Band parameter, sets the
width of the band above and below each of the prohibited frequencies set in parameters
505, 506, 507, and 508 (Skip Freq 1, 2, 3, 4).
For example, if this parameter is set to its default value of 1 Hz and parameter 505 (Skip
Freq 1) is set to 20 Hz, a skip band from 19 to 21 Hz is established.
As discussed in the description of parameter 504 (Skip Freq Band), the drive may be con-
figured to skip certain frequencies. These three parameters set the center of the three
skip frequency bands (with the width of each band being twice the value of parameter 504
– an equal amount above and below the skip frequency).
502 Voltage Boost Default: 1.0%
Range: 0.0–50.0%
Levels 1, 2
CAUTION
MOTOR OVERHEATING
Too much boost may cause excessive motor currents and motor
overheating.
Use only as much boost as is necessary to start the motor. Auto-
boost may be selected at parameter 501 (V/Hz Select) to provide
optimum value of boost to suit the load automatically.
Failure to observe this instruction can result in equipment damage.
503 V/Hz Knee Freq Default: 50
Range: 25–400 Hz
Level 2
504 Skip Freq Band Default: 0.2 Hz
Range: 0.2–20.0 Hz
Level 2
505 Skip Freq 1
506 Skip Freq 2
507 Skip Freq 3
508 Skip Freq 4
Default: 0.0 Hz
Range: Min Freq–Max Freq
Level 2