vfd parameters

Loads of them.

• Acceleration time
• Deceleration time
• Current limit
• Etc., etc.

A full list can be found in the user manual for the selected equipment.

• Acceleration time
• Deceleration time
• Current limit
• Etc., A full list can be found in the user manual for the selected equipment.
• dear sir,
• ok,i can find a full list in the user manual. but there is a big number of parameters in manuals. what i am asking is basic parameters or main parameter . you written accel time,decel time, current limit, etc. please go and so on and tell me 10-15 parameters like you had written whom you think are necessary for operating. if it is asked in a interview then what i should answer!! please guide me. its a repeated question and i don't no correct answer.

regards,

sp singh

Hi SPSingh,

Once you are clear about the function of VFD you get your answer.

1. Why do you require a VFD

To get smooth variable speed control. As you know that speed of an induction motor depends on its frequency f ( N= 120f/P) since Poles of motor can change as 2,4,6,8 etc.The speed can change in steps only, when your supply frequency is 50Hz/60 Hz.

The first parameter is, the required frequency dependent on the required variation of speed.

2. Capacity of VFD to drive the Motor to be used for the specific job.

The second parameter will be what is the VA rating of the VFD that is sufficient enough to drive the motor safely with out overloading.

3. The third purpose of VFD is to enable the motor to provide just required

torque for a specified requirement to avoid wastage of energy

( A technology used for Energy conservation)

Here the the voltage and frequency have to be smoothly accelerated or decelerated with the time parameter. This will be an important parameter of selection of VFD.

4. The quality of AC voltage wave form generated which depends on the quality of the design and components of the variable frequency controller and the inverter circuit

So the above four parameters are considered most important. if you can explain these points clearly to the interviewer then he will understand that you have conceptual knowledge of the subject.

for better knowledge read the link below

http://www.joliettech.com/what_is_a_variable_frequency_drive.htm