Bridgeport Interact 4 Series 2 to Acorn6 build

[Chaz]

Thats the plan A. If that won't work, and I can't see why not, I'll just run a new config of the software to use the knee as Z rather than the quill when I need to do deep boring jobs. I don't think that will be required though as in effect the Acorn / CNC12 will only do what the G&M code says so if the code says move axis ZZ at feed/rev then thats what it will do.

Cool. Do you have locks on your knee once its in place, will you just manually loosen / tighten? Ive never tested if the knee remains 'stable' if they are not locked. Suppose depends on how aggressive you are milling.

[richardb15]

I have a manual Elliot Sturdimill that is a bit smaller than the Bridgeport, but it has powered knee, X an Y feed on leadscrews and I currently use that for boring ops. That is fine without locking the knee off as the knee is so heavy it doesn't move, and for cylinder bore work I don't take huge cuts so I think it will be fine, time will tell!

[richardb15]

I have a problem getting one of my drive types to work with the Acorn. I've just set up on the bench with an X and Y axis. The X axis uses the Leadshine HBS2206S drive, and the Y axis the Leadshine H2-2206 drive. Both are driving an 863HBM80H motor. I have the direction and enable functions working fine and the X alarm works okay. Using the VCP X+ and X- jog buttons gives the expected forward and reverse rotation on the X motor and changes with the slow or fast feed selected.

On the Y drive I have it enabled and the alarm bypassed, when trying to turn the motor by hand it won't move and you can see on the HMI it trying to apply torque to hold position. However when connected up to H14 Step2 (or step 1 for that matter) it refuses to move, just holds position. The Y axis values are changing in Centroid but nothing on the drive. Connecting it to the (working) X axis step1 doesn't work either. However if I take the drive PUL+ wire from H14 Step2 and tap it on/off the +5v on H16 repeatedly the drive notches round as expected. Any ideas why it won't drive from the H14 connections? I thought H14 put out a 0v/5v signal? Report attached, any insight appreciated.

EDIT: I also wired the Y drive PUL+ and PUL- to a simple 555 astable circuit and get clean rotation from the Y motor at a 13kHz square wave

[richardb15]

I tried wiring the H2-2206 drive to the open collector outputs rather than the 5v logic one, so had permanent +5v to the PUL+, ENA+ and DIR+ on the drive, then the ENA- and DIR- to the open collector H2 connectors DIR2 and ENA2. With the PUL- wire from the drive connected to STEP2 I get no movement when I try to jog. However if I repeatedly touch the PUL- wire to the GND on H2 I get the motor stepping for each touch. I thought the open collectors would emulate this switching but I guess not. With a digital scope between +5v and the open collector STEP2 the signal is very messy without a pull up resistor, I tried a 1K and then a 10K and they give a cleaner signal but still no motor movement. Any ideas from anyone what I'm not doing correctly here?

[richardb15]

Here is the scope screen for the open collector setup and a 10k pull up resistor which results in mo motor movement



and here is the same setup but with the PUL- and PUL+ to the drive being powered from a 555 circuit, very different plots and the 555 one works fine



Note the time base is different on both plots. Why is the Acorn pulse not a 50% duty cycle and why is there a huge harmonic after each pulse, is that normal?

[richardb15]

Right, I went back to basics and wired the drives back into the 5v logic connections, redid all connections and wiring, and screwed the scope probes into the sockets for better connections. I also set the jog frequency to be 6.66kHz so around the same as the 555 setup. Here is the plot, 2us per division on the time axis:



Okay, I think I see the issue. The drive manual, link posted earlier with a translation from Chinese, requires the Thigh and Tlow to be at least 2.5us, and you can see on this plot the pulse length is about 2.2us. So how can one lengthen that pulse?

Here is a plot at 20us per division so you can see two pulses, the duty cycle is very low.


If I can adjust that pulse length I think I'll fix this drive issue. There is no parameter in the drives to accept a shorter pulse so that is not an option, its hard configured for 2.5us minimum.

[cnckeith]

looks like you are going down a rabbit hole!
i just asked our two EE's to jump in on your thread and help you out.
expect a reply from them in the am.
from your post i could not tell if you are using the 5 volt or 24 volt outputs on the AcornSix?
and did you / can you post links to the drive manuals of the drives you are using so the guys don't have to go hunt for them.
and please post a link to the photo album so we can see all the photos in one spot.
and please add photos of your wiring or a sketch or schematic of how you are attempting to wire.
also have you look thru the AcornSix Centroid supplied schematics for reference?
there are a few AC drives to AcornSix schematics, yaskawa, delta, dmm, sureservo etc..
https://www.centroidcnc.com/centroid_di ... m=acornsix

however i have notice some of these early china AC drives actually have stepper motor style input circuitry in them.. so that equates to they work best on the 5 volt step and direction connections on AcornSix

see the stepper driver connection schematics such as this one
https://www.centroidcnc.com/dealersuppo ... 147.r3.pdf

[richardb15]

Believe me, I've read everything available I could find but nothing seems to discuss the pulse width for the step signal. I've tried both the H14 5v logic connections and the H1 open collectors (at 5v and 24v with resistor, and with/without a resistor to clamp the signal feed to the drive), and sourcing and sinking, all work with the HBS2206 drives but not the H2-2206 ones.

I'm currently wired as per the S15147.r2 schematic as that should be the kiddie:


HBS2206 manuals here:


H2-2206 manual in Chinese and a machine translated version:



Full folder here:


As I mentioned, I believe it is all wired and configured properly. After much rabbit hole digging I believe the problem is the pulse width of the Acorn6 is too short for the H2-2206 drive to recognize. To validate this, how do I increase that pulse width on the acorn 6? I believe it is pulsing at 2.2microseconds and I want it over 3.0 to check my theory.

[suntravel]

A step rate must be selected for step and direction output mode. This will specify the maximum possible step rate, and therefore the width of
the step pulse. Step rate is 1250khz / (parameter 968). A parameter 968 value of 0 will be changed to 6 internally.
Nominal values for parameter 968 are listed in the CNC12 parameter screen.

With your setting P968=12 it should be >2.5 microseconds, but I would try P968=0 (it worked for me for all stepper drives so far)

Uwe

[richardb15]

P968 = 12.00000 - Acorn Step and Direction Frequency in (Hz) 0 = 200000 Hz, 1 = 1200000 Hz, 2 = 600000 Hz, 3 = 400000 Hz 4 = 300000 Hz, 5 = 240000 Hz, 6 = 200000 Hz, 12 = 100000 Hz 30 = 40000 Hz, 60 = 20000 Hz, 100 = 12000 Hz

Thanks Uwe, I'll try that when I next get workshop time, much appreciated.