VFD data sheet

[MikiBg]

Hi all!
Can someone tell me what are MINIMUM NECESSARY data for valid VFD data sheet? I'm writing it for the first time and I'm not sure. 250kW motor, centrifugal pump for water intake. Besides nominal motor power/current, is it necessary to specify starting current, maximum torque and speed range? Why is important to specify lower speed limit? I suppose it isn't related to soft start function and the latter is default. Anything else that I should know?

 

[itsmoked]

What doe you mean VFD data sheet? You are creating one for a VFD you've designed?

Keith Cress
kcress -

http://www.flaminsystems.com

 

[MikiBg]

No, it's a list of technical data requested in accordance to existing project. It will be send to manufacturers/vendors, and they should answer which of that are fulfilled by their equipment. The question is which data I have to put in data sheet to be sure that offered VFD will do the job properly.

 

[itsmoked]

Oh man.. You need to understand why a VFD is being used - in detail - or you can totally get screwed here.. BIG TIME.

We cannot tell you without more details then you probably know yourself. I would highly recommend you hire someone to spec out the VFD for you. Then you can shop that spec around.

There are probably 30 things you should have down on that sheet.

Further more there are things like service and support which should weigh in on this too. I would hire someone myself for one that big even though I've probably bought 25 VFDs.

You can contact me and I will try to connect you with someone if you can't hunt someone down locally. Where are you located?

Keith Cress
kcress -

http://www.flaminsystems.com

 

[MikiBg]

Yes, I know it isn't simply at all. I have some number of data defined, "just" don't know is that enough. My biggest concern are those stated in first post (starting current with DOL, max continuous torque/current required). The command line is: continuous flow meter-PLC-VFD. Motor manufacturer stated 28-50Hz as required speed range. Service, support and commissioning are not the issue in this stadium. I already have "controlled stopping" specified, but nothing about start. Do I have to specify it, or it is assumed as default function for every VFD? As far as I know, electrical grid impact requires soft start, and water hammer prevention requires soft start and gradually stopping.

 

[DickDV]

Better take itsmoked's recommendations before its too late, MikiBg. It's clear that you are not qualified to do this properly.

 

[MikiBg]

I guess u're right, guys. But sometimes, u have to manage somehow. I cleared some things with guys from mechanical department. I am also informed that this is first iteration of procurement, and all unclear issues will be discussed later with potential supplyers.
Thank you both for good intentions, specially Keith!

 

[jraef]

Since it appears you are stuck with this job on your own, you could take the "cheater's way out" and do a Google search for "VFD Submittal Data" to see what your compatriots ask for...

Keep in mind by the way that VFD is also used for Vacuum Fluorescent Display, so be careful.


"If I had eight hours to chop down a tree, I'd spend six sharpening my axe." -- Abraham Lincoln
For the best use of Eng-Tips, please click here -> faq731-376

 

[ozmosis]

it depends if you want to specify the lowest cost or the highest value for money. The latter would typically require a more detailed specification, more time to put together and a good understanding of the application.
Are you writing a spec for somebody to supply you with a VFD or writing a spec to sell a VFD?

 

[itsmoked]

To buy - as he states above...

Keith Cress
kcress -

http://www.flaminsystems.com