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Varible speed drive manfacture
2

Varible speed drive manfacture

Varible speed drive manfacture

(OP)
I would like to initiate a study to evalaute the suitablity of using variable speed mtor on one of big pump in our plant. Could you please provide me with names and websites of variable speed drive manfacturer.

Thanks

RE: Varible speed drive manfacture

2
IMO, you'd best leave such a study up to an independent engineer that will properly evaluate your system hydraulics and pay close attention to your specific operating methodology.  Those two factors can make the critical difference between a VFD either saving energy, or being an expensive energy hog.  Many pump manufacturers make a rough estimate of system hydraulics, if they look at it at all, and consequently do not evaluate the system hydraulics properly.  It is often also possible to save even more energy than what can be saved by a VFD, simply by reviewing the system for proper operation inside optimum design limits and/or by incorporating what are often small modifications in the method of operation, such as pumping mostly at night when power costs are low.  I'd suggest that you include those possible alternatives and options in your proposed study.  But please do find a company engineer or an independent engineer to do this study to help ensure a totally objective analysis.

If you want VFD manufacturers, there are hundreds.  A simple Google search will turn up much more than we can possibly want to name here.  

Come back if you want some advice on a particular manufacturer's product and it might be helpful to be prepared to discuss your operating methodology too.

**********************
"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/

RE: Varible speed drive manfacture

SZL,

I suggest you to follow BigInch's advise, he is a guru in the field of VFDs. Take a look at the thread below

thread407-260203: VSD energy savings
 

RE: Varible speed drive manfacture

Thanks ione.  But I'm certainly no expert in VFDs themselves.  Maybe I know something about their practical ability to save energy in pump systems when evaluated against the actual hydraulics of a system, while considering various design and operating alternatives, but otherwise VFDs are just another black box to me.   

**********************
"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/

RE: Varible speed drive manfacture

BigInch, you are far too humble, take the pat on the back they are rare!

Mark Hutton


 

RE: Varible speed drive manfacture

smile2 smile2 smile2  

**********************
"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/

RE: Varible speed drive manfacture

Big is not very precise.  What kW or hp range and voltage are considered.  You thin the manufacturer selection lots once you exceed about 10,000 hp.

RE: Varible speed drive manfacture

Yes I agree.  But then those guys do get much easier to find too.  

I admit that I said it because at least I personally don't want to see this forum turn into another e-bay-alibaba find it all here site for purchasing department managers.  Hopefully that viewpoint is consistant with those held by Eng-tips management.

**********************
"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/

RE: Varible speed drive manfacture

drivers are one thing - control/electrical something else.

ABB an Siemens are two large vendors of complete VFD drivers in all sizes.

Best regards

Morten

RE: Varible speed drive manfacture

I was a bit hastey posting before - what i meant to say were:

Your VFD consist of the motor and the controller/transformer. You could split the supply - but ABB and Siemens are two that can deliver both.

be aware that a standard motor may NOT be suited for VFD. The fan must have its own motor and nut just be powered by the main motor. If it is (as is very common) - then it will spin slower at slower speeds - and the reduction in air flow may be larger than what is required - thus leading to over-heating.

Best regards

Morten

RE: Varible speed drive manfacture

Manufacturers we use most often are ABB and Danfoss

RE: Varible speed drive manfacture

When I read this

Quote:

I suggest you to follow BigInch's advise, he is a guru in the field of VFDs.
My first thought was;
"No.Big isn't a VFD guru. We have those and big isn't one of them. Big IS a guru in the application of VFDs to pumping.
That's just what this OP needs."
A sincere compliment BigInch
Yours
Bill

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Varible speed drive manfacture

Thx Bill.  

That was my immediate thought too.  I certainly wouldn't want to insult you sparkies by even alluding to a title like "VFD guru".  Like I say, a VFD is a total black box to me, but I am proud to recieve your and other's compliments on what I have been able to figure out about their applications as pump drives.

Thx

Some day I'll have to take a look inside one, but without touching it.  Do they come with clear plastic covers? smile  

**********************
"The problem isn't working out the equation,
its finding the answer to the real question." BigInch
http://virtualpipeline.spaces.live.com/

RE: Varible speed drive manfacture

If the VFD salesman knows more than your electrical engineer in the application of VFDs to pump applications then get another electrical engineer.

If the VFd salesman knows more than your pump engineers about pump applications then give up and move away!

RE: Varible speed drive manfacture

Its said that salesmen know less and less about more and more until they know nothing about everything, while an engineer knows more and more about less and less, until he knows everything about nothing.

One thing for sure is trying to learn everything about everything is very time consuming.

**********************
"The problem isn't working out the equation,
its finding the answer to the real question." BigInch
http://virtualpipeline.spaces.live.com/

RE: Varible speed drive manfacture

It feels good when you get there though. tongue
  

----------------------------------
  
If we learn from our mistakes I'm getting a great education!
 

RE: Varible speed drive manfacture

Yes Scotty, YOU are my nominated candidate for "VFD guru".  There are one or two others around here, but you'll do nicely.

**********************
"The problem isn't working out the equation,
its finding the answer to the real question." BigInch
http://virtualpipeline.spaces.live.com/

RE: Varible speed drive manfacture

Oh no, there are far more knowledgable people than me in the Motors forum. Thy're just afraid to venture in here. Think of me as a missionary from the electrical world, helping you guys see the light. lol
  

----------------------------------
  
If we learn from our mistakes I'm getting a great education!
 

RE: Varible speed drive manfacture

Yes, I know they don't often grace us with their luminous presense, that's why I was happy to nominate  you.  We'll just have to settle for those dim LEDs on that globe there.  As they say, "The man with one eye is king in the land of the blind".-)    smile

Seriously, we blind denisons of the fluid depths always appreciate your enlightening contributions.  Even if we can't see them clearly, we do manage to get our heads around your concepts, if not our mouths.  Thank You!

**********************
"The problem isn't working out the equation,
its finding the answer to the real question." BigInch
http://virtualpipeline.spaces.live.com/

RE: Varible speed drive manfacture

SZL,

The biggest factor in determining if a VFD will save money, is the nature of your system. Static head vs friction is THE key factor.  

RE: Varible speed drive manfacture

Although it is surprizing how much where you operate in relation to BEP has to do with it too.   My general guidelines are a VFD does little to no good when you operate at 85 to 100% BEP, so its better to avoid them, if you spend 50% or more of your time inside that range.  Below that, static head makes more of a difference.  If you have a significant static head component, below 75% BEP may be reaching the too much head loss zone and below 50% becomes difficult.  If you spend 50% or more of your time at less than 50% BEP and have no static head, then you're talking good potential VFD performance enhancement possibilities, although you probably should have designed your system for a smaller flowrate.

 

**********************
"The problem isn't working out the equation,
its finding the answer to the real question." BigInch
http://virtualpipeline.spaces.live.com/

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