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Phil
Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 5648
Experience:  Retired HVAC/ Electrical & Boiler contractor. Industrial
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Happy New Year. Question 1. If I purchase a 2.2 KW 240V

Customer Question

Good morning. Happy New Year.
Question 1. If I purchase a 2.2 KW 240V X*****Motor and add a reduction gearbox 6.1 Ratio will this give me more torque. I am looking for as much torque as I can get on my prototype it has to be the above sized motor. I also want to be able to control RPMs 0 to 500. Ideal shaft size = 28mm to 30mm.
Question 2. Do you know a better way to achieve my above goals. I can convert to 3 phase if I have to.
Submitted: 11 months ago.
Category: HVAC
Expert:  Phil replied 11 months ago.

Hello,

a better way is to use inverter to drive the electric motor, it needs to be engineered...you can buy a chinese made one for around $125 with spotty reliabiity, or an American made one for $700+ made by Alan Bradley or other US mfgrs,

http://www.ebay.com/itm/Delta-AC-Motor-Drive-VFD-B-inverter-VFD022B21A-2-2KW-3HP-1-Phase-220V-New-in-box-/201148796368

That is an example.

It is easy to make any project non viable by specifying unrealistic specifications, 0 to 500 rpm is a bit extreme, it can be done of course but not cost effectively.

Regarding the inverter, I over size those so that they run cooler and more reliably. if you are trying to adapt a 3000 rpm motor to 500 rpm you are making things tough on yourself, it will be cheaper to buy an 1150 or 850 rpm motor as a base and then step that down to the speed ranges you want.

If you appreciate my input so far, locate the "rate your expert" link, and rate my work positively... we can go from there.

Lacking that I can spend days with a customer at my own expense,without any compensation. Rating does not increase your charges or close the question and it allows you limited follow up.

Full engineering services of course is another issue, we can discuss later,

Customer: replied 11 months ago.
I have no wish to be a member or associated with this site again this was a one of question I believe you are sneaky with the pay monthly concept if you try to access my account again I will treat it as fraud you say you can simply edit info. bullshit!
Expert:  Phil replied 11 months ago.

Hello again, I am a customer of the web site just as you are, I am just on the expert side, I do not work for the web site and have no control over web site policy,

If you select the 'contact us' link you can ask the web site management about their various deposit and membership offers.

Expert:  Phil replied 11 months ago.

On the topic of your need for low speed torque, an inverter will do that for you, it will do it progressively more efficiently as you select the lowest speed base motor available. If 3 phase is available to you, 1750 rpm 2kw motors are all over ebay at scrap metal prices, those are in very low demand... then fit it with a variable speed inverter drive,

Good luck with your project