[Pophamrt1]

Can you tell me if the Rutex drive is trapezoidal phase or sinewave phase ?

For what its worth the "Run Test Profile" section of Rutex's R2000 tuning software identifies all three methods (Rectangular, Trapezoidal, and Sinusoidal; see the attached link). But again, its in the testing section, not the setup area and its referred to as "motion" not commutation. It may just be referring to parameters/configuration the motor expects to see, not what the drive is actually providing.

[DerekZahn]

Yeah, I think you're right -- the screenshot is from configuring an R2020 which is for brushed motors.... and brush motors commutate themselves :-)

I would guess that setting is for the path the motors go through during a test run, to see how the PID algorithm responds to different types of movement.

[damae]

Where's Rutexus? It seems they would be able to give an answer to this simple question:

Can Rutex 2030 drives do sinusoidal commutation?

Rutexus, if you're out there, give us a shout back and let us know. Quite a few of us bought motors hoping to buy 2030s to run them...

-D

[JFettig]

Gentlemen,

I'm away until Monday evening. I did not get time to try the 1000 watt motor, but Vladimir said a similar motor he was aware of worked fine with the R992H. I'm confident they will work too-enough that I ordered 10 1000 watt motors myself. I warned him about the expected orders. He said he still has some R992H's to sell, and that there was a slight delay (caused by him being so busy programming some of the windows support programs for his plasma control) on the motors arriving by the first week of November as scheduled, but that they will be out real soon.

Tom Eldredge

^^^^^
away till monday,
Think about it, thers like 700 of these motors out there, I think like 500+ counting on these drives at least.... I am pretty sure thats the numbers, I think there were like 300-400 1000w, 100 400w, 2 sets of 100 300w then some 100s that not many people bought.

[miljnor]

I believe the rutex drives are trapazoidal in nature.

[rpm mill]

I guess the question anyone who bought these motors would have is "What do these drives cost?" Can you throw out a ballpark value?

Evodyne

For the surplus Sanyo Motors about $650 is the least expensive that I know of and it would be marginal on power for the 1KW motor. It's difficult because all the major manfactures want to sell the complete package (powersupply, controller, amp, cables, ect). They spend a lot of R&D money on development and some of that money is used to design in dependencies (buy my package or it may not work very good). I have very limited information on the 2030 drive but if you put the 1KW Sanyo motors to work they will want lots of amps, I think the drive will need lots of cooling and when I looked at the 2030 I didn't see much cooling in place. (Don't take this as more than there are lots of questions to be answered.) At work I use brushless servo motors, at home I use steppers. My accuracy at home is just as good, it just takes me longer to get there. I will post a link here, I teach a class and it is required reading for my students(Note this is not an endorsement of any product).
http://www.tormach.com/document_libr...C%20Design.pdf
I will say this the boys at Tormach did there homework.......

[ger21]

I am guessing that anything but sinusoidal drive is going to cause a rough low speed issue if run by any other method.
Al.

I plan on using these on a router, and they'll be running at full speed most of the time. Would this then be less of an issue? And would it affect acceleration, or will the accel be fast enough to not have a problem? In the first post Tom said he had them working nicely with the R992H, but didn't elaborate. Guess we need more info from him when he returns.

[damae]

Oops. You're right, he did say he'd be gone until Monday. I'll be patient then.

I should add that while we're all hoping to get our motors running with Rutex and are kind of counting on them for help, I think they are going above and beyond by paying so much attention to their customers' interests and spending their time to actually purchase and test the motors for us.

[ger21]

I think they are going above and beyond by paying so much attention to their customers' interests and spending their time to actually purchase and test the motors for us.

They DO have the potential to make a LOT of money selling drives for these motors.

[walter]

Would these work ? --> http://www.simpleservo.com/Drives/SS100SS200.html

PDF specs: http://www.simpleservo.com/images/PD...o/ss1-2pg4.pdf


EDIT. Also check out ParkerHannifin SLVD drives: http://www.compumotor.com/home_press.htm

[DerekZahn]

That SimpleServo device looks pretty nifty. Appears to be about $600:

http://www.123servos.com/Pricing/SimpleServoPrices.html

On a different subject, I see that a lot of servo drives run off the "mains" and do not have huge transformers in them; I guess if they are grounded properly this must be an OK thing to do. It would obviously be attractive if one did not have to purchase a power supply. Such a device running off the normal AC line would have a bus voltage of about 170 volts. I'm thinking that these 100v motors could probably operate off of amplifiers like this, as long as the speed and current is kept under control. Anybody agree or disagree?

[andy55]

On a different subject, I see that a lot of servo drives run off the "mains" and do not have huge transformers in them; I guess if they are grounded properly this must be an OK thing to do. It would obviously be attractive if one did not have to purchase a power supply. Such a device running off the normal AC line would have a bus voltage of about 170 volts. I'm thinking that these 100v motors could probably operate off of amplifiers like this, as long as the speed and current is kept under control. Anybody agree or disagree?

170 VDC for the servo drives sounds about right.
The servos are 100VAC, meaning 100Vrms or about 140 V amplitude (280V peak to peak).
Since usually they are driven with a H-bridge that can direct current both ways through the windings it is enough to have the DC voltage at about half of the peak to peak value. some margin is good for switching losses etc. so 170-180V is real good.
(where I live we have 230VAC and that just rectified would be a bit overkill...)

as I understand it with any higher voltage than that you will just create exessive heating of the switching transistors...

andy

[Al_The_Man]

Such a device running off the normal AC line would have a bus voltage of about 170 volts. I'm thinking that these 100v motors could probably operate off of amplifiers like this, as long as the speed and current is kept under control. Anybody agree or disagree?

Most of these are isolated from the incoming AC by means of a switching supply, Often transformerless.
The DC buss on some of the AMC I use of this type have a Buss voltage of around 160vdc.
They are used to control motors such as ElectroCraft etc that have a operating voltage of around 80vdc.
Excess Current is usually the enemy of servo's, the mean current is usually taken care of by the PWM switching, as most servo amps have a method of controlling maximum current by a current limit control.
Al.

[Xerxes]

I have looked at 100W P5 specs and it says that the voltage constant is 14.6 mV/rpm. So at 3000 rpm without load it would need only 0.0146*3000 = 43.8 VAC voltage. Under 3x overload it would take 43.8VAC+3ohm*8.9Amps = 70.5VAC.

Am I correct?

[m_j01]

For what it's worth, Sanyo specifies the drive method for the 100W motor to be "Rectangular wave" (See page two in the attached data sheet).

[rpm mill]

I think the specification you are looking at is the output of the encoder. To drive a AC servo motor with a square wave would be very interesting. The drawing that is posted is helpful but it is a revB for this motor from 1995, it is not unusual for a company to issue revs every year or two. Anyone out there got a more current drawing and spec sheet for this motor. Also I read that you can change the rotation by changing the A and B encoder wires. I don't think so. On the motors I have worked with it takes a 6 wire swap or more. 2 Hall wires switch, 2 Motor power wires switch and the encoder A and B switch. I can't tell you which ones because there is no uniform code as to how to define the motor phases and the Hall sensor phases. If you want to wire up a motor the most simple case you can have is 10 wires (3 halls - 3 motor power - 2 encoder - 1 5volt+ and 1 5volt ground) and they all have to be right or it won't run. You don't have to use the encoders inverted channels, they are used to make interference problems go away. No one can tell what terminals the wire colors go to unless you know the servo amp to be used. One manfactures V Channel is Channel U to the next Mfg. and on and on we go and when you get them running just right with a Trapezoidal amp you may find position errors start to creep in sometimes big sometimes small and sometimes they even COG and break a lot of expensive things. I do have one application where a Trap amp is use on a 3 phase AC motor. But in this application the motor is used as a velocity motor and not for position. Anyone looking to make a the Sanyo a spindle motor could look at a low cost Trapazoidal amp.

[eat]

there is some pdfs here
http://automation.lonne.se/main.php?...d91f2f4806794e
hope this helps some one

[miljnor]

posted by m_j01
Sanyo Motor Drive Method
For what it's worth, Sanyo specifies the drive method for the 100W motor to be "Rectangular wave" (See page two in the attached data sheet).

posted by rpm mill
I think the specification you are looking at is the output of the encoder. To drive a AC servo motor with a square wave would be very interesting.

I personaly don't think they are talking about the encoder. 1. Because as far as I know all encoders give a digital output (at least for the current modern ones) so why list it since it is Identified in the document. 2. Its listed under the drive requirement.

I am no expert but the diffenence between an AC brushless and DC brushless involves how you drive it. I beleive that DC motor controlers Drive just 2 poles at any one time and AC drives drive more like a conventional inductive motor, by giving all three phases to the motor. But I believe you can run either motor in either fasion, but one runs better at high speed (sinusoidal) and one runs better at lowspeed (trapazoidal)

Michael t.

[miljnor]

posetd by Al_The_Man in "AC servo motor vs DC servo motor post"
Actually when running, the DC brush-less exhibits cogging at low speed due to the resolution of the commutation whereas a good quality DC brushed with skewed rotor is smooth down to zero (when running).
The AC sinusoidal motor which is constructed identical to the DC brush-less has the smoothness of a DC brushed.
This is why if you intend using a DC brush-less motor without gearing at very low speeds, you will see a step like pattern of rotation.
The advantage, apart from less maintenance, of a DC brush-less or AC servo is the fact that the windings are on the stator, so cooling is much more effective.
Although the DC brush-less and AC sinusoidal motors appear identical, manufacturers call them DC brush-less because there is only two windings powered at a time compared to a true AC servo where the three phases are conducting.
Al

This is support data from someone who does know from another post

Michael t.

[DerekZahn]

As for the encoder being "Rectangular" -- I suppose this is in contrast to a feedback that uses analog signals (most commonly called a "resolver"). But it does also say that under drive type, so who knows.

As for driving the motor with a trapezoidal controller, I would think the issues would be most pronounced at low speed, for two reasons: 1) the torque is not constant because the signals sent through the windings don't change even though the magnetic fields are moving around which affects the force they exert. 2) transition between commutation states is sudden. This causes an audible "click" that can also be felt on the motor shaft.

The question is whether either of these issues cause problems that interfere with the operation of an actual machine. My guess is that it will be fine with a drive like the Rutex, but somebody should try it to make sure!

I find the "clicking" to be annoying so I'm off noodling with my own controller design, but for people who actually want to get stuff done instead of goofing around, I don't see any reason in theory that a trapezoidal drive should be a disaster.