hello,

3x380v 1.1kw v20 driver;

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motor label;

Delta 230V;

Star 400V;

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Currently the motor is star connected to this driver. The only question I want to ask is can I connect the same motor to the same driver in delta? If I do, what should I do? As a parameter setting?

Thanks

Tractor

 

AutoGen_2379672

hello,

3x380v 1.1kw v20 driver;

-------------

motor label;

Delta 230V;

Star 400V;

--------

Currently the motor is star connected to this driver. The only question I want to ask is can I connect the same motor to the same driver in delta? If I do, what should I do? As a parameter setting?

Thanks

The drive will output 400Volts, 3 phase.

The motor windings in STAR will operate the motor correctly from this drive, to a frequency specified on the nameplate 50 to 60 Hz. As the speed / frequency is increased the impedance of the motor coils will increase reducing the current, and torque produced.

This can be overcome by connecting this motor in Delta, and operating from a 400Volt supply from the inverter drive, the impedance of the motor coils can be overcome by making the Voltage to Frequency line Voltage applied at 87Hz.

This configuration will apply 230 Volts at 50Hz, and 400Volts at 87Hz, the torque will be retained up to 87Hz

See below. Rate

Entry type: Application example Entry ID:25338130,Entry date:03/21/2014

(6)

Rate

SINAMICS G: Operating motors at higher frequencies

Tractor

Does this mean that if I connect this motor to a v20 driver with a delta connection, should I be able to drive between 50 Hz and 87 Hz?

Tractor

Provided the motor can be operated at this increased speed, this usually refers to the rotor, being able to accept the higher speed without failure, refer to the motor manufacturer for this.

The link below refers to '87Hz Operation.

https://cache.industry.siemens.com/dl/files/130/25338130/att_7156/v1/25338130_betrieb_von_motoren_mit_hoeheren_frequenzen_v2_1_en.pdf

Tractor

 My main problem is this. This 3x380 1.1kw v20 driver is connected to the 0.75kw motor that I mentioned on the label in the factory settings of the driver. Sometimes the motor does not turn and draws 3.5 Ampere current and the driver generates the A501 alarm. When I apply a force to the motor from the outside with my hand, the motor starts to turn normally. Sometimes it does this very often. Based on your experience, what do you think is the possible cause of the problem?

Edit: A gearbox is connected to the front of the motor 

Thank you

Tractor

A 0.75kW motor will draw 1.8 Amperes, full torque at 50Hz, your motor is drawing a high current and will be in 'current limit'. Where the frequency will be limited to protect the drive and motor.

You are using this in 87Hz operation?

It is possible that the motor settings are not correct for 87Hz operation, check the 'application guide'.

Consider:

To control the coil current as the frequency goes from zero to maximum frequency, the applied Voltage is also controlled from a low value to line Voltage, this is the 'Voltage to Frequency relationship'. For 'normal' operation full motor Voltage is applied at 50Hz, current will be as name plate at this value, to produce nameplate torque.

As discussed in the 'application guide', to overcome the increase in coil impedance at high frequencies, the motor is connected from STAR to DELTA, here the coil impedance is reduced, to be acceptable for 230Volts at 50Hz and 400Volts at the increased frequency 87Hz.

Note that the inverter drive must have the current rating suitable for running the motor at 230Volts, see nameplate for this.

I guess that either the motor connection is incorrect, or the Voltage to Frequency settings are not right?

Tractor

 What is happening now is this. The motor is star connected. The driver is 3x380 v and all settings are according to star connection. I did not make any 87 hz setting or any other setting. The problem is as I mentioned: everything works normally and draws normal current. The motor stops maybe 4-5 times a day or more and the driver produces a501. At this moment, when the gearbox connected to the motor is applied manually in the direction of the motor while it is energized, the motor starts moving again and a501 disappears. The driver (1.1kw) draws maximum current (3.5A). The motor (0.75kw). Driver on the factory settings

Tractor

As with these configuration routines, it is not easy to be specific regarding a solution. I would reset the drive to default, and start again; by making the minimum of settings in order to test the motor and drive.

Tractor

 First of all, thank you very much. I will try this. The first thing that comes to my mind is that the motor power is not enough for this job.