Compumotor microsteppers

[Stevie]

I've managed to buy 2 Parker Compumotor AL microstepping drives at a good price

Next question; how can I control them with a PC; they seem to have the inputs that make me think direct connections to the printer port would work; am I right?

[vacpress]

stevie, a good place to start might be at the gecko website. look at their info on how to setup their geckos, and see what you can infer for your drives. i would guess a bunch are obvious.. just be VERY carefull not to put the motor voltage into the wrong place! most things burn good with 60 or 80 volts at 15amps or whatever.. im not familiar with the drives, so i am only guessing what supply you might be using... look for compumotor manuals and see if they have overlapping info if yours is not available.

hope it helps

[Stevie]

I found the manuals ok; but they are not really geared to the simple set-up we see here
I'm not too electronic savy; but i feel there must be some way to interface with a PC
Here a shot of an AL drive

[Stevie]

Here's the Compumotor S Drive Specifications from Parker

Performance

Accuracy ±5 arc min (0.0833°) typical.

Unloaded-bidirectional with Compumotor supplied motors. Other motors may exhibit different absolute accuracy.

±1 arc min (0.0167°)

Loaded-in addition to unloaded accuracy, per each frictional load equal to 1% rated torque.

Repeatability ±5 arc sec (0.0014°) typical.

Unloaded-one revolution returning to start point from same direction.

Hysteresis Less than 2 arc min (0.0334°) unloaded-bidirectional.

Resolution 16 selectable choices: 200, 400, 1000, 2000, 5000, 10000, 12800, 18000, 20000, 21600, 25000, 25400, 25600,

36000, 50000, 50800

Waveform Selectable. Allows microstepping shaping for optimum smoothness or relative accuracy. Pure sine; -2%, -4%, -6%,

-10%, third harmonic included.

Speed/Torque Refer to speed-torque curves on page C71.

Motors

Type 2-phase hybrid permanent magnet, 1.8 degree.

Breakdown voltage

(HIPOT) 750VAC minimum

Number of leads 4, 6 or 8

Accuracy Grade 3%

Inductance 0.5 mH minimum; 5.0 to 50.0 mH recommended range; 80.0 mH max

Dimensions Refer to drawings on page C72.

Amplifier

Type 20 kHz fixed frequency, variable duty cycle PWM (pulse width modulated). Current controlled, bipolar type. MOSFET,

IGBT construction.

Number of phases 2

Dimensions Refer to dimensional drawings on pages C73 and C74.

Protection*

Short Circuit Phase-to-phase, phase-to-ground.

Brownout If AC supply drops below 85VAC.

Overtemperature If internal air temperature exceeds 158°F (70°C).

Auto standby If selected, motor current ramps to 75%, 50% or 25% of preset value if no step pulses are received for 1 second.

Rated current levels are resumed upon receipt of next step pulse.

Self test This feature (used primarily for testing and verification of correct wiring) rotates the motor at approximately 1 rps for 6

revolutions in the CCW direction and 6 revolutions in the CW direction.

Step Input High-going pulse, 200 nsec min. width; max. pulse rate is 2 mHz. User-supplied driver for the step and direction inputs

should be capable of providing a minimum of 6.5 mA to a maximum of 15 mA.

Direction Input Logic High = positive (CW) rotation.

Logic Low = negative (CCW) rotation.

User-supplied driver for the step and direction inputs should be capable of providing a minimum of 6.5 mA up to 15 mA.

Shutdown Input Logic High = amplifier disable.

Logic Low = normal operation.

User-supplied driver for the shutdown and zero phase inputs should be capable of providing a minimum of 2.5 mA up

to 30 mA.

Zero phase Logic Low = resets the motor phase currents to the zero state. It is primarily for linear motor applications. The input

must be active for 100 ms before the first step pulse is received.

Logic High = normal operation.

User-supplied driver for the shutdown and zero phase inputs should be capable of providing a minimum of 2.5 mA up

to 30 mA.

Fault Output Conducting = normal operation.

Not conduction = drive fault.

Power Input 90-130VAC 50/60 Hz

Environmental

Operating 32°F to 122°F (0°C to 50°C)

Drive Maximum allowable ambient temperature is 122°F (50°C). Fan cooling may be required if airflow restricted.

Motor 212°F (100°C) maximum motor case temperature. Actual temperature rise duty cycle dependent.

Storage -40°F to 185°F (-40°C to 85°C)

Humidity 0-95%, non-condensing

AL drive is very similar; just it has 3amps max to the motor

I got an S drive too; so I have 2 AL's and 1 S; 3 drives for the mill project
If I do end up needing some kind of inderxer; I'll just have to get one; bit I still feel a PC can connect to it; it needs step and direction

[ger21]

I think this is the right manual for what you have. http://www.parkermotion.com/manuals/a-ax/a_ug.pdf
If so, page 26 shows you how to give step and direction pulses to run the drive. So you SHOULD be able to use these with Mach2 or TurboCNC. It looks about as simple as electronics get, but I don't know what I'm doing either.

One problem I see, though, is that these supply the motors with 170VDC, at up to 3a/phase. If this is not adjustable (I didn't read that far), you need to use motors that are at LEAST 7V or more (25x overvoltage is ~ 170V), or you'll probably damage your motors.

PS. The airport was on exit 9. And you didn't remind me it would take 45min to go through AFTER I was over the bridge.

[Stevie]

Hey Gerry; you took 45mins to drive to the airport from the bridge; wow; was it the trucks all lined up
I thought it was pretty simple; I've done it a lot quicker

[Stevie]

Yeah I had that .pdf too; looked it over; I'm lost; hehehe

But I've found if you study things long enough it starts to make sense

[ger21]

No, it took me 45 minutes from you're side of the bridge to the booths. About 400 yds. Then, 5 minutes to the airport. I thought I'd pull up as the wife's plane was landing. I was half way to the booth when she called asking where I was. Apparently, the entire city of Sarnia travels to the states on Sunday's and goes back home around 5:00. No trucks, either.

You shouldn't need an indexer, just the simple circuit I pointed out in the manual.

[Stevie]

Sorry about the wait Gerry

Still back to the Compumotor microsteppers; I've been buying them off eBay; got some sweet deals too; got a Vexta 5 phase for $26 and it looks brand new (list is over $839)
http://www.plccenter.com/Detail_New2...facturer=VEXTA
THe Parker Compumotor AL's I got 1 for $69.95 and the other for $56; the first $69.95 is brand new in box; both these listed for $1500 new
I've also bought a Zeta4 with motor for $100.50; (list $1076 without motor)
Finally a Parker Compumotor S6 for $86 again with motor (list was $1301 witout the motor; new)

Pricing provided by
http://www.plccenter.com/partlist.as...&T1=COMPUMOTOR

I feel this is a better way than the drives most use here; at least there are plenty of drive protections built in; even if I did have to buy some fancy indexer; I'v still not spent anymore than Gecko's

The 5 phase I want for my lathe for the X axis (it will be smooth for sure) The Zeta4 will be for my Z axis

The 3 Compumotors will be for my Japan servo steppers 300oz/in Nema 34; all for the Mill project

This has got to be the way to go with stepper drives; eBay is full of them if you know where to look

If you want 2 5 phase drives look at these
http://cgi.ebay.com/ws/eBayISAPI.dll...808514478&rd=1
I bid on the last pair to $90; they went for $160 (so I'm cheap) but as these are the second batch I feel they will go for less; maybe $100; for a pair of drives this is very cheap; I'll bet about 1/10 of the original cost; and they look like new

[ger21]

If you don't go the step and direction route I mentioned above, and you go with the indexer, what software will you use? I'm assuming that the indexer won't accept step and direction, since it appears that it outputs step and direction. The popular (and cheap) software everyone uses (Mach2, TurboCNC) output step and direction. Quite possibly, the money you saved on the drives will be aeten up (and then some) by the indexer and special software needed to run the thing.

I could be wrong, this is just an assumption I'm making here. The beauty of what everyone uses here, (Xylotex, Gecko, Mach2, TurboCNC...) Is that everythiing is relatively cheap and it all works well together. Although you can get the high end stuff for cheap on Ebay, making it all work can be a different story.

I'd try to hook them up with the step and direction circuit, if I were you.

[cutfinger]

Much of the Compumotor drives and indexers work with their "X language" which is not G-code and use a serial port rather than a printer port, so be careful.

[Stevie]

I think 5vdc + or - is not really dependant on which port is emminates from; if the drive needs 5vdc for step and direction just the same as the cheaper drives most use here; whats the differance; the only other input I see is the shutdown input
I'll paste it in here
The inputs are optically isolated and may be driven (activated) by providing a positive pulse to the plus input with repect to the minus input. These inputs may also be differentially driven. The input drivermust provide minimum of 10mA (20mA maximum).
Step-Pulse_Input
The step pulse input has the following limitations
500 nanosecond-pulse minimum
40%-60% duty cycle at 15mA (750khz max pulse rate)
Input currents greater than 15mA may result in lost steps at high pulse rates

Direction-Input
This input meets the input specifications listed above.
A Minimum of 2ms of set-up time is required before and after the receipt of the step pulse

Shutdown Input
Amplifier Disable
Tjis input has the same electrical characteristics as the STEP input. you can enable it when the motor is not moving. The input must be activated for 100ms to disable the amplifier. The shutdown input must be deactivated for 100ms before the first step pulse is received

The last part is what I'm not sure about; now if the software like Mach2 has the pulses and the direction; the only thing I'm not sure about is the mA from the printer port