DMM Tec Servos

[lgalla]

Post your experience or questions on DMM servos.
Larry

[lgalla]

Web site
Motion Control Products - DMM Technology

[lgalla]

What is the max voltage rating on the Dyndrives and 900W servos?I have a 60V supply.
Larry

[mactec54]

lgalla

It's best not to go over 48v for the Dyna Drive 2 50v max, There is a 100v drive in progress, but are not sure when it will be made available for sale, That will double the performance of that same motor

[lgalla]

Here is possibly the stupidest question ever on the zone.If the servos are A/C,why is the power supply D/C.Are the A/C servos brushless?Sorry for the stupid questions as there is little information on A/C servos on the zone.
Larry

[Al_The_Man]

Larry, Simply that a DC supply is needed in order to electronically create the variable frequency output as in AC sinusoidal or the switching pulses for BLDC.
VFD's also have use the same principal for 3 phase induction motors, i.e. create 3 phases from a DC supply.
Here is the BLDC commutation.
http://users.tinyworld.co.uk/flecc/4...otor031102.swf
AC and BLDC motors are built practically identical.
Al.

[mactec54]

lgalla

The motors are AC servo's & brushless, It's like when you have a VFD you put AC into the drive, but you don't get AC out of the drive,you get DC for the supply to the AC induction motor, These & other AC servo motors run the same way

[kregan]

I am considering using the 3 axis system on a RF31 clone. I would love to hear more from anyone using the system.

[mactec54]

kregan

There are a lot of Zone members that have the Dmm system, They have there system running, but have not completed there machines

You can see the Dmm system working YouTube - cncvids 028.AVI
The build is here http://www.cnczone.com/forums/diy-cn...kes_first.html

This is another Build http://www.cnczone.com/forums/cnc_wo...5_cnc_cut.html

[rodjava]

Hi,
I might be one of the initial users of the DMM system. I bought my DMM system in July 2010 and will be coming up to 1 year using my cnc router on a weekly basis. I'm only a home shop machinist and not into production.

I have a build log and started talking about servo choices and DMM here: http://www.cnczone.com/forums/diy-cn...s_first-5.html

My initial questions about the DMM system were:

Aren't AC servos only used in very high end machines?
How can DMM price their AC servos the same as DC servos.
The DMM encoders have some very high encoder counts compared to other servo encoders.
Aren'e servo motors hard to tune?
What kind of service will I get from a new company like DMM?

I was pleasantly surprised to learn that, Yes, AC servos are typically used on big expensive machines and the DMM AC servos are a scaled down version of the same.

I still don't know how DMM set the prices competitively with other servo motors. I'm guessing a close association with the manufacture as well as a large wholesale order. All I know, is that I took advantage of the prices.

I'm not into production and encoder counts was not a big concern for me. I just knew that more is better. It was a bonus for me that the encoders were pre-installed on the AC servos and pre- wired too.

I found out that tuning these servos was not as complicated as I have read in many cnc zoners post. DMM supply's some simple software that tunes the servo's perfectly. You just need to follow the documentation carefully.

The biggest advantage with going with DMM was working with their tech support. I asked some pretty dumb questions, not just once, but two or three times. Each time my question was answered in a timely manner and thoughtfully in a way only a novice electrician would understand. In other words, they didn't make me feel as if I was wasting their time.

Knock on wood, but I have not had any problems with by servos or other components from DMM. I'm planning on a building a 4th axis using the same AC servos.

Sorry I cant quote any technical specification with the AC servos. That's not my thing, but making chips is!

Rod
San Francisco

[kregan]

Can you repost those build thread links... they both say page not found?
Nice video!

Originally Posted by mactec54 kregan There are a lot of Zone members that have the Dmm system, They have there system running, but have not completed there machines You can see the Dmm system working YouTube - cncvids 028.AVI The build is here http://www.cnczone.com/forums/servo_...nc_router.html This is another Build http://www.cnczone.com/forums/servo_...r_project.html

[mactec54]

kregan

Try the links now, I don't no what happened to them, They looked ok when I posted them, they are working now, Plus Rod just posted, one of the links is his build