Changing from AC to variable speed DC motor

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Kludge

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Foozer said:
I got a 1/2 hp PM motor sitting right here doing nothing

Got the specs & I'll be off to respond in a bit.

Shepard/Lab mixes. Good rodent hunters and too big, 90+ lbs for them overgrown flying chickens (Eagles) to cart off.

Had a pair like that - mother was a Springer & father was the neighborhood. Not quite 90# each but close enough. Nothing I did could convince them they weren't lap dogs so I guess I should be happy I had a big lap. Thunderstorms were especially exciting because they both wanted to be on my lap at the same time.

They were great watch dogs. They'd watch anything that happened aboard the boat. "Ooooh, there goes the TV ... and the microwave ... and the coffee maker ... Wait. Coffee maker. Better stop this action or daddy's gonna be highly provoked!"

BEst regards,

Kludge
 

Stan

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That is a good toy for the student in school but not much help if you are powering machine tools. Running 12 volt motors at 100 amps isn't going to be done with the electronic kit. In addition it provides no control over min and max speeds, no current limiting and no acceleration control. These features are all standard on the type I referenced in an earlier post.

 
K

Kermit

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Stan said:
That is a good toy for the student in school but not much help if you are powering machine tools. Running 12 volt motors at 100 amps isn't going to be done with the electronic kit. In addition it provides no control over min and max speeds, no current limiting and no acceleration control. These features are all standard on the type I referenced in an earlier post.

Would you prefer a link to multi hundred dollar controller?

I can do that too!


Can't make everyone happy, so I just settle for having fun pissing off the ones with short fuses. ;D
 
K

Kludge

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Stan said:
That is a good toy for the student in school but not much help if you are powering machine tools.

That depends on the application, doesn't it? For what you prefer, the one you spec'd is good. But the one Kermit indicated will handle just light of 1 HP out of the box and can be made to handle more with not a lot of effort.

The difference is I can buy the one Kermit pointed to any time and modify it to suit my needs without a whole lot of added expense, dependent on what's in my junk box ... er, spare parts supply at the time. The one you indicated shows up periodically and is snapped up by people who need heavier controllers without taking the time to assemble and customize them.

Some of us are very strange and like to solder and tinker with circuits as well as machines. Buying a kit and making it sit up & dance (which is significantly more than I can do ... dance, that it) suits us and we're happy. Plug and play suits you and you're happy. So everyone's happy and we can all sit back and enjoy our machines. :)

BEst regards,

KLudge
 

Stan

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Kludge: I may have missed something on that link as I just took a quick look, but this is what caught my eye

# This DC Motor controller can handle up to 16Amps, but PCB trace capacity would have to be beefed up with some hookup wire where DC motor current runs through the Printed Circuit Board.
# Requires operating voltage of 9 - 18 VDC.

If you have a 18 volt motor and a power supply to drive the controller, you can get a maximum of 288 watts if you jumper the traces on the pc board. 1/4 HP will do fine on your small lathes but it it is not just a plug and play controller.
 
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Kermit

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If anyone is serious about steam engines.

They can buy one too!


I thought the point of this topic was ideas, not who is more "serious" than the other?

Doing it yourself is what makes these types of hobbies fun for some of us. If you don't like tinkering with circuits the by all means PURCHASE what you need. If you DO like to tinker with circuits then... ;D


My way or the Highway sucks, there's alot of lanes on this road. Change lanes or pass or take an exit, just stay off my assbumper,
Kermit
 

Foozer

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Kermit said:
Another link to cuss, or is it discuss?
http://www.reliance.com/mtr/mtrthrmn.htm
Be prepared, this one will be to complicated for most but will be elementary to others.

Good link, not to bad a read. Does answer at least to my level of understanding why the brushes on my doner motor are off center
One method of reducing the arcing due to non-linear commutation is to shift the brushes away from the geometrical neutral position.
Motor is designed to favor one rotational direction, so I better get my rump out and walk the talk, remount the motor to agree with its build design.Fortunately its supplied mounting system makes this an easy change.

All these links for DC Power supplies have there merits, and I can see the 12/24v 15amp unit as a controller for say a windshield wiper motor powered hacksaw controller for those who just like to be a tad off the bubble.

I made the switch from the original AC driven system 'cause I'm lazy. Switching belts around gets tiresome in a hurry and I avoid using the backgears, if I bust em replacements are hard to find. DC drive therefore sounds like the solution.

What do I want this conversion to do?

Make the wheels on the bus go round and round. Problem Stated

Considerations
1. I'm clueless
2. I'm cheap
3. Minimal thinking
4. Easily available
5. Skill level
6. Not burn the Barn Down!

1. Clueless and Cheap, searching around for the results of others who have tackled this conversion bring up as a common denominator, Treadmill Motors

2. Minimal thinking and availability, Treadmills are designed is as many shapes and sizes as a womens dress, finding one that is suitable just a metter as lookin over the racks (E-bay, Craigslist, local thrift stores) till one jumps out and says Howdy.

3. Skill level, I have seen items on this board that in my wildest dreams I could never match with my stone axe and hammer view of the world. As much a bolt on operation as possible for this thick head.

"Treadmill" motor is there, pulleys are there, mounting brackets, controller and various pieces of stock all in one package. All for under a C-note, or rather 69 GBP, 125CAD, 154AUD.

As reported by the ol Kill-A-Watt meter the converted unit draws around 5 amps, well within the components capacity. All wires securely attached and a new GFI in the wall plug circuit. All in all pleased with the conversion. Room for improvement, sure, will it happen, maybe. Its functional, does what is asked of it.

But whitout post such as
[author=Kermit link=topic=4210.msg44098#msg44098 date=1235313068]
I would not have gained further insight into the working of DC motors.

 
K

Kludge

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Stan said:
Kludge: I may have missed something on that link as I just took a quick look, but this is what caught my eye

If you have a 18 volt motor and a power supply to drive the controller, you can get a maximum of 288 watts if you jumper the traces on the pc board. 1/4 HP will do fine on your small lathes but it it is not just a plug and play controller.

Up toward the top they mention handling a 100v @ 7a load which works out to a wiggle under 1 hp. Without looking at the spec sheet, I'm guessing this hits the transistor's power limits while the 16 amps bumps up against the current limits. I'd have to look at the wee beastie's curves to give a more definite answer. With a little added circuitry, two of the power transistors could be operated in parallel which would increase the power handling capability as would changing to a meatier single transistor.

You're right. This is not a plug and play solution. It's for tinkerers like me who love the smell of solder in the morning (or any other time) and accept the risks of letting the smoke out at inopportune times. The kit mentioned is fairly basic yet it can be made to do everything a commercial speed control does with some "judicious adjustment".

The plug and play units I meant are the ones you mentioned - prebuilt and ready to rock 'n roll as is. (Actually, being an old school solder jockey, I'd probably find "improvements" to make in them as well. ;)) As a rule, they are fatter but they are also intended for different (heavier) applications than the kits are.

This is a one size doesn't fit all situation of which life presents many. That's part of what makes it so much fun!

BEst regards,

Kludge
 
K

Kludge

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Kermit said:
Another link to cuss, or is it discuss?
http://www.reliance.com/mtr/mtrthrmn.htm
Be prepared, this one will be to complicated for most but will be elementary to others.

This is beautiful plus gives me ideas how to rework series wound motors to do muchly moreso cleverer thingies. I like doing muchly moreso cleverer thingies.

Who will I piss off next?, Tune in tomorrow and see ;)

As long as it's not Pele, ainokea. :)

BEst regards,

Kludge
 
K

Kludge

Guest
Foozer said:
Considerations
1. I'm clueless
2. I'm cheap
3. Minimal thinking
4. Easily available
5. Skill level
6. Not burn the Barn Down!

1. Disproven already.
2. This is a bad thing?
3. Thinking leads to brainaches. They are bad things.
3a. OTOH, Danica McKellar on hand to help with the math would be nice. :D
4. Reflects back to 2.
5. "Fine adjust with a 6# sledge" works nicely.
6. No sense of adventure, huh?

BEst regards,

Kludge
 

Andrew_D

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Stan said:
If anyone is serious about DC motor controllers. take a look at this ebay ad, ending soon.

http://cgi.ebay.com/DANFOSS-Penta-K...ryZ71393QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Be aware...I bought one of these controllers from the same seller.

The one I got was NOT a Cycletrol C2000, even though the case sticker says it is. Once I opened it up, I found that the circuit board was not the same as the C2000 info I had downloaded.

More digging produced the manual for the VariSpeed A2000, also from Danfoss (although the line has since been sold to Graham Motors). The board was similar to the A2000, enough that I got it working. Plus, the A2000 can run up to 3HP motors!!! ;D

There isn't much info out there on the A2000. If anyone buys one of these and needs help, drop me a message...

The seller has been informed of this, but I don't know if they will change the listings. My best guess is that the original owner upgraded the boards at some point, but kept the original cases.

Andrew
 
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