VFD

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Anonymous Poster #1	VFD 12/28/2014 5:06 AM
	Dear All, We have carry out the commissioning of VFD, during the test when initiate start the motor running but were getting fluctuation. any advise please. Regards Moh'd
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JRaef Guru Join Date: Sep 2006 Location: California, USA, where the Godless live next door to God. Posts: 4665 Good Answers: 804	#1 Re: VFD 12/28/2014 9:22 AM
	Not nearly enough information. But here are some common mistakes. 1) Your application requires Vector Control, but you are using basic V/Hz control. Most VFDs are now capable of Sensorless Vector Control. If yours is, use that control method and follow ALL instructions for commissioning it properly. 2) You are using Sensorless Vector Control, but you did not perform an auto-running procedure on the motor and drive together. That is an absolute must, it is not optional when using SVC. If you ate using an ABB drive, they call it something different (I can't remember), but it is the same thing anyway and if you do not do it, the output is unstable. 3) Your speed command is coming from an analog input signal, and there is electrical noise on that signal, especially once the drive is running and producing noise. If you tested the signal without the drive running, you do not see the problem because it is the running of the drive that creates the noise. This is usually the result of poor or missing signal wire shielding (screening). __________________ All I every really wanted to be, was... A LUMBERJACK!.
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lyn Guru Join Date: Oct 2008 Posts: 42355 Good Answers: 1693	#2 Re: VFD 12/28/2014 12:34 PM
	Moh'd, Is there anyone there who know's anything about electricity? About motors? About motor controls? How to use a telephone? About manufacturer's web site and how to find it? Do you have the operator's manual? Did you read the operator's manual? Do you know who made the VFD? Have you tried to contact them? Have you asked for divine intervention? Have you asked a local electrician for help? Disconnect the VFD, put it back in the box,if it had one, and run the motor without it.
	Reply Good Answer (Score 2)

capblanc Guru Join Date: Jul 2008 Location: Mallorca, Spain Posts: 567 Good Answers: 15	#5 In reply to #2 Re: VFD 12/31/2014 4:50 PM
	why the rudeness? By all means suggest the 0. P. contacts the manufacturer/ main agent but there's no reason to be unpleasant about it. He may well have read the manual, but in what language, and translated at what quality. He may be reading a manual in English, not his first language, badly translated from Chinese. __________________ En la casa del herrero, cuchillos de palo!
	Reply Off Topic (Score 6)

lyn Guru Join Date: Oct 2008 Posts: 42355 Good Answers: 1693	#6 In reply to #5 Re: VFD 12/31/2014 4:58 PM
	Rudeness? All the questions are legitimate, and directed to the OP. Have anything constructive to add? Or just trying to waste time? If you want help the OP go for it. Nobody's stopping you.
	Reply Off Topic (Score 5)

Phys Guru Join Date: Feb 2006 Location: middle of nowhere, Pennsylvania Posts: 2603 Good Answers: 63	#3 Re: VFD 12/29/2014 10:59 AM
	Let me explain your problem to you. I go to the doctor and tell him I was running and passed out. What is wrong with me? (I don't bother to tell him if it was 35 degrees C or 10 - I don't tell him if I ran into a low hanging limb on a tree - I don't tell him if I was running for 2 minutes or 6 hours - I don't tell him if I had eaten a regular meal or was on a starvation diet to lose weight - I.... Do you see the problem here? Now read your post and apply this knowledge to that. Facts PLEASE!!!! __________________ Remember when reading my post: (-1)^½ m (2)^½
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Crabtree Guru Join Date: Jul 2007 Location: Commissariat de Police, Nouvions, occupied France, 1942. Posts: 2599 Good Answers: 77	#4 Re: VFD 12/31/2014 4:50 AM
	Yes, of course. In situations like this, the rest of the Engineering community would hire someone who has some idea of what s/he is doing who can apply both the contents of the manual and a good oversight of the installation to do the commissioning. Why the "we" have chosen to come here instead would be the biggest complete mystery of 2014. __________________ Good moaning!
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capblanc (1); Crabtree (1); JRaef (1); lyn (2); Phys (1)

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