Help - motor upgrade for jet extractor

[LBCarpentry]

Mooorning - I want to increase the power of my Jet dual extraction system. My world of engineering knowledge is suggesting that I simply have to upgrade to motor. It is currently a 3 phase motor,

is it an easy swop? Can someone direct me to a more powerful motor. The more powerful the better, right?

I currently have this....

I’ve found these New motors on eBay.

would one of these be suitable?

https://www.ebay.co.uk/itm/143028477039
TIA

 

[Trevanion]

Unless you’re bogging down the motor there is absolutely nothing to be gained from more horsepower. There’s no point in putting more power in the impeller if the existing impeller can only flow a certain amount of air. You need a bigger extractor, not more power into that piddly thing.

 

[Ttrees]

Hello
Don't know if a larger motor will do much, so I will wait with curiously.

I suggest to get the answer you want, it would be important to know what sized impeller you have.
Shaft size should be known aswell if shopping.
Many of the folks who build cyclones and the likes often end up going back to the drawing board and upgrading everything ala Pentz.
You need to state your runs also for a good answer.

Presume you know of the Bill Pentz website?
He advocates a 5 hp motor and if I'm not likely mistaken, a 15" impeller.
This is for a ducted system to get around 1000CFM.
I won't pretend I understand any of it.


A disgruntled reply, as I missed out on a cracking deal last week on a system.

Tom

 

[Trevanion]

A disgruntled reply, as I missed out on a cracking deal last week on a system.

Tom

I was offered a 50hp cyclone tower once, must’ve been 10 metres tall. I could have it so long as I took it away, “Nah, you’re alright!”

 

[Ttrees]

You could have made a shed from that!
This one was close to what Bill specified,
I was after the three phase motor and impeller which might have needed a trim.
Good job I have such a large bandsaw, as it acts as a passive collection system

 

[LBCarpentry]

Unless you’re bogging down the motor there is absolutely nothing to be gained from more horsepower. There’s no point in putting more power in the impeller if the existing impeller can only flow a certain amount of air. You need a bigger extractor, not more power into that piddly thing.

How DARE you insult my JET VORTEX CONE. Just because she doesn’t have the power to suck a dandelion dry doesn’t mean you can’t hurt her feelings like that!

 

[Myfordman]

You might get more suction from a higher power motor run from an inverter that will increase the speed a bit BUT make sure the new motor has the same frame size as your existing motor as you will have to do untold mechanical modifications to get it to fit. ( shaft size, recutting keyway, mounting hole PCD)
That is possibly a 100 frame size (check this!) and you might find 4hp on a 100L frame where the motor body is longer but everything else is the same as a 100

 

[guineafowl21]

How DARE you insult my JET VORTEX CONE. Just because she doesn’t have the power to suck a dandelion dry doesn’t mean you can’t hurt her feelings like that!

You’re the one wanting to upgrade her attributes...

 

[Ttrees]

It has a 3hp motor though,
I would think it could be possible to get some better performance
from this motor...
If the starting inertia of the 3 hp motor wasn't up to scratch, for a oversized impeller, and the motor was dual voltage, and not fixed star wound as the sticker implies, having a ramped start up, I guess the performance could be upped, although I wonder if this poses consideration to the runs, or something else I have missed on?

I would think you could just buy something else rusty and be able to run it with your supply for the price of an impeller alone.
Not counting a cyclone build.

Depending on your budget, and time..
It might be worth looking into/for at 5hp dual voltage motors, and
some old rust buckets and seeing if you could trim down a larger impeller to suit.
A 5hp VFD is the largest one you can get at reasonable cost.
A VFD could ramp up the motor to account for the extra weight of a larger system impeller, much like what I have stated looking for the best setup for a 3hp motor, which might suit the home workshop.

I'm not saying its a good idea, but from an ignorant point of view, it seems...
possibly a practical way to accomplish a really good DC for cheap.
It might take some trial and error to get the sweet spot in regards getting the
optimum impeller size and blower size.
Just a thought though.
Would love to read more on the subject in a more digestible format than Bill's website.
Thanks
Tom

 

[Inspector]

Putting a new motor won’t improve anything if it turns the impeller the same speed as the existing motor does. Your best bet is to get a variable frequency drive (VFD) to increase the speed. I believe you can get one to take 400v 3 phase and vary the frequency up or down. If you up it to 60 cycle like we use you will increase the speed to 3400 rpm giving you a 20% boost in airflow. Without taking the impeller you a company that balances such things I wouldn’t go over 65 cycle.

As pointed out the impeller is the limiting factor and is likely a 12”. Most 2 hp and 3 hp DCs use the same impeller. The reason a 3 hp flows more air is they have more filter area allowing the airflow. You also must have bigger diameter ducts. 4”/100mm duct flows 400cfm at max. A 6”/150mm duct will flow 3 times as much air. Small DCs can’t flow that much air over any distance which is why Bill Pentz recommends 5hp 15” or 16” impellers. A cyclone has internal drag, the Pentz being about 2” with most others being up to 4”. The other reason he suggests the 5 hp.

Pete

 

[clogs]

it's like putting a bigger turbo on ur car.....
to get the best performance u have to modify everything else......
Can I suggest, just buy another extractor to do less work......ie ...split the system up to do fewer machines per extractor....
then of course it depends on air speed to the size of ur chips......
I like mine with salt and onion vineger......hahaha...
be careful out there.....

 

[Trevanion]

I don't really pay too much attention to the extractor but the impeller is about 600mm in diameter by about 300mm in depth running off the end of an 11kw motor, it throws the shavings down a 15ft x 5ft channel box with bags on top which then pipes into a big 5x5x5ft box with more bags on top, box has a linkage welded on for telehandler to take it away and dispose of.

 

[mcgranag]

Some interesting info on this page, power goes up fairly drastically for a modest increase in performance.

https://www.axair-fans.co.uk/news/applications/understanding-basic-fan-laws/