Questions tagged [vfd]
Variable frequency drive, a three-phase AC output motor controller. Questions about vacuum fluorescent displays should not receive this tag.
154
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19 views
Effect of PWM output from Variable Frequency Drive to PSC motor
I looked at VFD diagram and seem like it use Sine-PWM Output without any filter to drive psc single phase ac motor
Inductance and capacitance seem to work with pure sine wave but PWM output have a lot ...
3
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2answers
211 views
How to choose and wire a Variable Frequency Drive [closed]
I have a 1.5 HP 3PH 240V Leeson motor that I want to drive my lathe, but I want to vary the speed. I asked a question on this site about a month ago about how to do that and the recommendation was a ...
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0answers
18 views
What scheme would you indicate for a nobreak system with variable frequency output?
I'm pretending to make a system that charge batteries (or a single battery) and then produces 3 independent AC outputs (all having the same common, in a star connection).
But I want to have ...
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1answer
28 views
Understanding VFD speed control input using a potentiometer
I am working on hooking up a potentionmeter as a speed control input to a variable frequency drive.
Here is are the diagrams from the VFD manual:
(Its a Lenze AC Tech SMVector ESV112N01SXB; full ...
0
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1answer
39 views
VFD Motor Bidirectional Control
So I have a control panel which controls the speed and direction of a motor in a sliding mechanism. the direction can be inverted using a tri-state selector on the panel. the selector input is a ...
0
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1answer
62 views
VFD for a 3-phase delta-connected 415V~ motor
When a motor starter is to be replaced by a 3-phase 415V~ VFD, can the existing motor be used without changing its winding configuration (star/delta)?
The motors are from different manufacturer
...
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2answers
44 views
What exactly is 1.x and 2.0 power scalar V/f control in VFDs?
These are terms that I have come across in multiple operating manuals for VFDs and usually, they just mention that it's used for variable torque applications. My doubt is "what exactly is it?&...
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2answers
61 views
Is upsized reactor allowed for the comparitively less motor HP?
We have a LV-MCC in our commercial outlet having a 480 VAC, 15 HP VFD with line and load reactors in series with it. The VFD is sized for 22.0 A (normal duty), the motor has a horsepower rating of 10 ...
2
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1answer
64 views
Tesla Model S inverter DC bus voltage
I was recently researching about this Telsa electric car inverters where i found one intresting thing.
Usually in the voltage source inverter the DC bus voltage will be around 600 to 650 V considering ...
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1answer
22 views
Delta Servo Drive 220V/400V Series
ASDA-A2 Delta Servo Drives including two types: 220V and 400V series that it seems the difference is input voltage of the Servo Derive. but i doubt 220VAC or 400VAC is line to line voltage or line to ...
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2answers
76 views
Motors Delta/Star connections to VFD
I've selected 230/400V motors (delta/star) and corresponding 400V VFDs for pump motors. Now I've been asked why I haven't selected 400/690V motors (delta/star), that are the standard and usually ...
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1answer
39 views
AC Induction Motor Slip and Torque control Vs V/f control
I am trying to understand this github code for speed control of AC Induction Motor. It calculates slip value to adjust the speed of motor. I wonder if its the same thing that is called constant V/f ...
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1answer
134 views
4-20 mA output from Arduino for VFD
I'm a beginner with electronics, so everything has to be explained in simple terms to me.
I have an Arduino with a program which provides a value via the Analog output, so that is anything from 0-5 V....
1
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1answer
54 views
Why are inverter modules extremely oversized in VFDs?
I was checking a faulty Schneider VFD (ATV312H037N4) which is rated for a nominal output current of 1.5 A. Turns out the rectifier bridge of the inverter module (FP10R12YT3) blew up and after reading ...
0
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1answer
40 views
Explanation request of a paragraph in a VFD manual about a diode, should I add it or not?
I didn't fully understand this paragraph in a VFD manual:
My question is: is the free-weeling diode exist inside the drive, or should I put an external one?
3
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3answers
89 views
Which frequency is the best for a 3-speed Motor?
Sorry I dont know the appropriate terms that should be used in this subject!
I have an inductive motor, it has 3 different speeds (or windings) at 50 Hz:
350 rpm / 700 rpm / 970 rpm
I want to ...
0
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2answers
89 views
Converting single-phase 120 V or 240 V into three-phase 4-wire 120/208 V
I am needing to convert either 240 V or 120 V single-phase into 120/208 V three-phase 4-wire. The load needed is 30 A. My panel can supply up to 100 amps, so the amperage isn't an issue.
I've looked ...
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1answer
44 views
suggestions for how to implement a weird VFD jog mode?
I'm a total noob at electronics, but my employer has asked me to try to program a replacement VFD on our industrial stone-cutting saw. Everything works on it now, but I need to figure out how to ...
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4answers
129 views
What happens to a high power inductive motor if you decrease the RPM to half the rated in terms of current, torque and heating?
and what is minimum possible RPM ratio for a high power motor
3
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3answers
990 views
How many times of a frequency of a PWM can properly generate a sine wave to drive a motor?
I know PWM with dense and loose duty cycle is used to generate sine wave for applications such as 3-phase motor driving. But, How fast does it require to properly generate a sine wave to drive a motor?...
0
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1answer
58 views
Using a 3-phase Transformer After a Variable Frequency Drive for Voltage Reduction
In the plating industry generally 42V - 3P motors are used to rotate the barrels that hold the products to be plated. This is because the contacts of the barrel cannot be isolated (because barrels are ...
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1answer
30 views
Firing time in VFD inverter
Just a quick one. When looking at schematics for a VFD, I see the same circuits as diodes used in the converter (AC to DC), capacitors in the DC bus and transistors or thyristors used in the inverter ...
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1answer
38 views
Does a load reactor eliminate the need for EMC cabling?
The company I work with installs ventilators driven by VFD's. To save on cost of EMC cabling we use load reactors at the VFD outputs. (Other considerations for not using EMC cabling have to do with ...
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0answers
46 views
VFD configured for six-step output instead of SPWM?
I need a transformerless inverter which generates a 3 phase 230 VAC modified sine wave output from 325 VDC input. Unfortunately, it seems these are rare, at least high power models. Can a VFD (with DC ...
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0answers
481 views
isolated 5v PWM to 0-10V
I'm trying to convert a 5V PWM signal to 0-10V through an optocoupler to drive a VFD.
The output "0-10V" should be 0V when PWM duty cycle is 0%, and 10V when 100% (linearly !).
Here is what I've come ...
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2answers
76 views
Parameters of the 3 phase geared induction motor
I have a 3 phase geared induction motor. The name plate is below image.
I couldn't find any datasheet from internet.
Explain me parameters that on nameplate for entering to VFD.
I need to know Rated ...
0
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1answer
57 views
Can I operate a 500kW/1500rpms motor at 35Hz with 400kW inverter?
In stock we have a 3 phase induction motor with a rated power 500kW and 1490rpms.
What is the smallest frequency inverter which we can use to operate this motor in a machine with a maximum power/...
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1answer
106 views
Variable Frequency Drive with AC motor, 30kW
I have a VFD that controls an AC motor which compresses air. It is an 30kW motor. I have set the parameters required to drive the motor and it runs the motor but not properly.
During the test the ...
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1answer
79 views
VFD as general use inverter
I'd like to have 3ph 208 in my house for general use (not a motor). If I run the output of a single phase to 3 phase VFD through inductors or a 1:1 transformer will it smooth the SPWM .output into an ...
0
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1answer
171 views
Termination of SY cable shield at VFD and 3 phase motor?
I am wiring a single to 3 phase VFD to a 3 phase motor (240V delta). The 3/4HP motor powers a lathe in a domestic setting. Supply voltage is 240V 50Hz.
As per the VFD instructions, I am using ...
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3answers
1k views
Braking Methods of Induction Motor in VFD
As you know, we can stop an induction motor by plugging or regenerative braking. What I'd like to know is that when controlling induction motor with VFD, which braking way VFD uses? It seems to me ...
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2answers
1k views
How to Size Line Reactors and Understanding Reactor Specifications
I've got a 600 VAC, 75 HP VFD that I want to place line and load reactors in series with. Usually, I find charts like this that give me a horsepower table to follow as they are the easiest to use. ...
0
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1answer
63 views
Vcc drops on connecting variable resistor between it and ground
I have a VFD with a control board I am trying to fix. It requires an external variable resistor to be connected between the +10V terminal, analog reference terminal and ground. I found that on ...
0
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2answers
55 views
How VFD affects an isolated IOT system
To avoid noise from the external system I tried to isolate the internal completely. So I added DC-DC isolated converter with signal isolation. I have attached the picture. Still when reading data and ...
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3answers
1k views
Can a Variable Frequency Drive convert standard wall outlet (120V/15A/single phase) to ~220V 3 phase?
In my workshop I have a device that requires 220V 3 phase power, with a requirement of up to 1.5kVA. In North America, my wall outlet provides ~120V/15A single phases.
(EDIT - my device can take +/- ...
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1answer
76 views
Slip Control vs Constant V/F Control for 3-Phase ACIM
I am trying to understand how is Slip Control different from Constant V/F control. If I need to control the speed of 3-phase ACIM then its slip would obviously change with its rotational speed then ...
0
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1answer
35 views
Speed control using direct torque control of induction motor
Is there any steady state error present in speed output at any load in direct torque control of induction motor?
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1answer
56 views
Voltage source & current input
I am working on a project where I have a current source (analog output from a PLC) controlling a VFD. Based on the position of the dipswitch, the VFD will accept either a current or voltage input. The ...
2
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1answer
337 views
Motor / VFD / Protective Earth
I have little experience with AC motors since I'm majoring in Mech.E. My team is setting up an AC motor with a VFD to control the movement of an airfoil inside a metal cage we built. I understand the ...
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2answers
153 views
Does a 3-phase VFD work if one phase is reduced (e.g. with a dimmer)?
If you have a 3-phase VFD running a 3-phase motor, and you use a leading or trailing edge dimmer on one or two of the input phases, will the VFD continue to operate normally, pulling more current from ...
3
votes
2answers
342 views
Miscalculating the nominal power using nominal current and voltage of a VFD
A variable frequency drive datasheet has current parameters named as I2N and I2hd. If Im not mistaken these currents are the per line currents for the drive output as follows where I showed in red ...
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3answers
729 views
A very basic question about VFD output frequency
I know that a VFD's inverter stage creates alternating voltages at a desired frequency for the terminals of a delta induction motor(stator voltage freq.).
Normally without a VFD the nominal freq. ...
0
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1answer
392 views
operating a motor with a undersized vfd
A centrifugal pump requires 21.6 hp to flow 350 gpm at 2800 rpm with a 230/460V, 40 hp, 2-pole (3600 rpm) motor. The VFD available can operate up to a 25 hp motor at 230V, with a maximum output of 68 ...
1
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1answer
45 views
DC bus correction for inverter VFD via PWM modulation
This is a question concerning an inverter circuit without PFC.
Single phase AC is rectified and pooled on DC bus capacitors.
From there the DC voltage is modulated at 5kHz on 6 IGBTs, emulating ...
2
votes
1answer
86 views
Why use many-pole motor for high speed?
I found in this teardown analysis of the Nissan Leaf drive motor that it runs up to about 10,000 RPM but is an 8-pole motor. My understanding is that the inverter cost goes up with frequency. The Leaf ...
2
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2answers
644 views
Powering a 3 Phase 230VAC Motor with 28 12V Batteries wired in Series
Mechanical Engineering student here. I'm a part of a senior project team that trying to run a 40 HP 230 VAC three phase motor with a 40 HP VFD for a hydraulic pump. Our plan is to wire 28 Lead Acid ...
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1answer
170 views
Problem in temperature transmitter because of VFD (Variable Frequency Drive)
I made an amplifier of PT100 bridge which operates on 24V DC supply and gives 0 - 10V DC for 0 - 400°C when tuned. The circuit is as follows :
Here P2 + and P4 S+ are shorted and P4 S- is left open....
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2answers
199 views
Not using all 3 phases of sine filter
I want to run a single phase motor with a single phase VFD.
I don't believe that the motor is rated to run with a VFD. To compensate for the issue I would like to use a sine wave filter. ...
1
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1answer
171 views
Inductor Machines: why is constant flux achieved before reaching nominal speed?
It is observed that an induction machine increases its voltage linearly before reaching its nominal speed. This is achieved due to the emf generated by the rotor movement.
However, I find it ...
2
votes
2answers
72 views
AC motor must be run off inverted DC?
I am looking at the datasheet for a motor. This is an AC induction motor designed for use in electric vehicles. It includes the statement [my emphasis]:
The motors are designed for installation in ...
