Another VFD Question

ddmunroe said:
Hi Jim, I'll do more research for over here, many of my HB friends and machining contacts are buying things engineer related from the USA. Even with shipping it's cheaper. As far as the unit I won't go cheap cheap I prefer mid range pricing and get the most value per dollar, 88 lbs !! Jeez I hope not that heavy .... as I say I'll do some research if so so be it.




Hi did you get any temperature readings for when the motor was overheating before and after with the fan installed, good idea !
:))
dd
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Hot enough that it burnt out before, it feels warm to the touch now but thats all
 
JimDawson said:
I agree with your VFD Selection.

Another motor type that you might look into is a BrushLess DC (BLDC), also known as servo motors. Maybe in the 1.5 to 2 Kw range. They are a 3 phase motor with a permanent magnet rotor. These have a much flatter torque curve and will produce almost 100% torque at 0 rpm. Also the weight is about 1/2 that of a standard 3 phase motor of the same power. I have seen these for sale in the USD$ 500 range with the controller, they may also be powered by a VFD.

There was a pretty good discussion of BLDC motors here http://www.hobby-machinist.com/showthread.php?t=23297&p=206307&viewfull=1#post206307
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You mentioned servo motors, at the end of my research last night I started to read about them and saw as you mentioned they have lots of torque at 0-low revs EG 10 -50-100-500 rpm. This is more what I'm looking for. A servo motor vfd controlled 2 or 3 hp depending on the weight will go 2 or 3 hp. I need the lightest combination. One thing I need to learn more about is this brushlless technology no brushes and computer controlled so what I said earlier is not correct. (servo motor vfd controlled)
Q: Are all servo motors brushless ? therefore they have there own controller not through a vfd

I found a supplier here for servo motors and controllers called WEG. Do not know prices yet.
Which company did you refer to in saying "500.00 for motor and controller.
May have got a few facts incorrect but as I say still grasping the concept and terminology.
For the record if a servo motor has brushes is it controlled by a VFD
If a servo motor is brushless is it controlled by a controller is this a fact
I am continuing my research
dd
 
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ddmunroe said:
Q: Are all servo motors brushless ?
dd
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No. A servomotor is just a motor coupled with an encoder so that it can be used in a closed-loop control system. Servomotors are often BLDC these days but they used to almost always be DC. An induction motor coupled to an encoder and driven by a VFD could be used as a servomotor, though I would not recommend it for very low speed operation.
 
ddmunroe said:
You mentioned servo motors, at the end of my research last night I started to read about them and saw as you mentioned they have lots of torque at 0-low revs EG 10 -50-100-500 rpm. This is more what I'm looking for. A servo motor vfd controlled 2 or 3 hp depending on the weight will go 2 or 3 hp. I need the lightest combination. One thing I need to learn more about is this brushlless technology no brushes and computer controlled so what I said earlier is not correct. (servo motor vfd controlled)
Q: Are all servo motors brushless ? therefore they have there own controller not through a vfd

I found a supplier here for servo motors and controllers called WEG. Do not know prices yet.
Which company did you refer to in saying "500.00 for motor and controller.

dd
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I finally found the thread I was looking for. http://www.hobby-machinist.com/showthread.php?t=23465&p=207824&viewfull=1#post207824 this thread references the Chinese servo motor I was talking about in the low price range.

Something like this might work for your application.
 
sparkness said:
You can absolutely use a 1hp VFD for a 1Hp motor that is what it is rated for, no need to go to a larger model, you can use a larger vfd on a smaller motor . I have used several different brands, and each have some good features. automation direct and teco are the least expensive and easy to program. the automation direct 1hp does not have the ability to use a brake resistor but has some built in braking. you can display scaled rpm , amps. Mitsubishi is a bit of a pain to program but offers a lot of features. As hvontres stated using a larger motor is good for when you use slow speed . on my 10" sheldon i have 1hp motor and vfd, I no longer use the back gear - just turn the knob on the vfd . I also run the motor up to 50% faster at times to get more rpm for finishing . Search the internet and you will find several places to get a good deal. I recommend buying new as apposed to used off of ebay because people selling used ones seem to ask way too much. here are a few sites which I have purchased from and had no problems. www.automationdirect.com www.dealerselectric.com www.factorymation.com
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I just wired up an Automation Direct GS2 1hp 120 vac in, 220 vac 3 ph out. The GS2 definitely provides for resistor braking.
 
uncle harry said:
I just wired up an Automation Direct GS2 1hp 120 vac in, 220 vac 3 ph out. The GS2 definitely provides for resistor braking.
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The GS1 series does not provide for a breaking resistor, the GS2 series does. Also when needing to use 120V input, the GS1 series is limited to 1/2 HP. The GS2 series has a 120V input, 1HP model. I always purchase the GS2 units. I have several.
 
Re: Another VFD Question (looking for a supplier)

Hi
Can anyone recommend a supplier for servo drive / controller package 2-3 hp.
Needs to run either on 220 or 415 ac power input. (220 1 phase 415 3 phase)
I don't think the hertz matters but in Australia the hertz is 50, service here is very slow
The internet search is the easy part, then after the phone call no one gets back to you.
Input appreciated
dd
 
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Re: Another VFD Question (looking for a supplier)

ddmunroe said:
Hi
Can anyone recommend a supplier for servo drive / controller package 2-3 hp.
Needs to run either on 220 or 415 ac power input. (220 1 phase 415 3 phase)
I don't think the hertz matters but in Australia the hertz is 50, service here is very slow
The internet search is the easy part, then after the phone call no one gets back to you.
Input appreciated
dd
Click to expand...


dd, I sent you a PM
 
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