I/F Start Function - Danfoss VACON 100 FLOW Series Application Manual

VACON® 100 FLOW
Application Guide
11.3.4.5 (ID 605) U/f Midpoint Voltage
Location in the menu: P3.1.4.5
Use this parameter to set the middle point voltage of the U/f curve.
This parameter gives the middle point voltage of the curve if the value of P3.1.4.1 is programmable.
11.3.4.6 (ID 606) Zero Frequency Voltage
Location in the menu: P3.1.4.6
Use this parameter to set the zero frequency voltage of the U/f curve. The default value for the parameter is different for each unit
size.
11.3.4.7 (ID 1590) Flying Start Options
Location in the menu: P3.1.4.7
Use this parameter to set the flying start options. The parameter Flying Start Options has a checkbox selection of values.
The bits can receive these values.
• Search the shaft frequency only from the same direction as the frequency reference
• Disable the AC scanning
• Use the frequency reference for an initial guess
• Disable the DC pulses
• Flux build with current control
The bit B0 controls the search direction. With the bit set to 0, the shaft frequency is searched in 2 directions, the positive and the
negative. With the bit set to 1, the shaft frequency is searched only in the frequency reference direction. It prevents the shaft move-
ments for the other direction.
The bit B1 controls the AC scanning that premagnetizes the motor. In the AC scanning, the system sweeps the frequency from the
maximum towards zero frequency. The AC scanning stops when an adaptation to the shaft frequency occurs. To disable the AC
scanning, set the bit B1 to 1. If the value of Motor Type is permanent magnet motor, the AC scanning is disabled automatically.
Use the bit B5 to disable the DC pulses. The primary function of the DC pulses is to premagnetize the motor and examine the rota-
tion of the motor. If the DC pulses and the AC scanning are enabled, the slip frequency tells which procedure is applied. If the slip
frequency is less than 2 Hz, or the motor type is PM motor, the DC pulses are disabled automatically.
The bit B7 controls the rotation direction of the injected high frequency signal, which is used in the flying start of synchronous
reluctance machines. Signal injection is used to detect the frequency of the rotor. If the rotor is in a blind angle when the signal is
injected, the rotor frequency is undetectable. Reversing the rotation direction of the injection signal solves this problem.
11.3.4.8 (ID 1610) Flying Start Scan Current
Location in the menu: P3.1.4.8
Use this parameter to set the flying start scan current as a percentage of the motor nominal current.
11.3.4.9 (ID 109) Start Boost
Location in the menu: P3.1.4.9
Use this parameter with a process that has a high starting torque because of friction.
Use the start boost only when starting the drive. The start boost is deactivated after 10 s or when the output frequency of the drive
is more than half of the frequency of the field weakening point.
The voltage to the motor changes in relation to the necessary torque. It makes the motor give more torque at the start and when
the motor operates at low frequencies.
The start boost affects a linear U/f curve. To get the best result, do the identification run and activate the programmable U/f curve.

11.3.5 I/f Start Function

With a PM motor, use the I/f Start function to start the motor with constant current control. A high power motor gives the best
effect. With a high power motor, the resistance is low and it is not easy to change the U/f curve.
The I/f Start function can also give a sufficient torque for the motor at start up.
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N O T I C E
Parameter Descriptions
AB298035655957en-000201 / DPD01083