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Do not allow any movement until servo drives ready
« on: November 13, 2011, 02:09:10 PM »
Hello.

My machine uses servo drives that output the ready state. For example at initial power up the drives are still not "ready". During a crash the same will happen and they will be "not ready" again. This works and outputs a led to mach to display on the screen.
My question is how can I prevent the DRO moving if any of the servos are not ready. For example at start up, I press the reset button, then the drives are "booting", during that time if the user presses any jog key, the DRO changes and no movement is done (as the drive is unready). I have check the inibit axis button linked to a brain but appears not to be working.
Any ideia?

Offline Hood

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Re: Do not allow any movement until servo drives ready
« Reply #1 on: November 13, 2011, 02:17:53 PM »
I have fault signals from my drives which I tie together (with other conditions) in the ladder of my PLC which then inputs that as an E-Stop signal to Mach. So unless my drives are out of fault condition then I can not get Mach out of  reset. It also means if any of my drives (axis or spindle) fault then so does Mach.
I am not sure how your drives work however as you mention reset boots them? I power my drives via my E-Stop button, it pulls in contactor (amongst other things) which power the drives.
Hood
Re: Do not allow any movement until servo drives ready
« Reply #2 on: November 13, 2011, 02:50:16 PM »
No PLC here, so must be brains.
Clicking reset makes the charge pump on that outputs signal to enable the drives.

Offline Hood

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Re: Do not allow any movement until servo drives ready
« Reply #3 on: November 13, 2011, 02:59:06 PM »
Do your drives take a long time to enable?
If you are waiting for a ready signal when drives have to be enabled then its not going to be so easy as the only way I can think of is to use the Input 1 inhibit function. Problem with that is you can still Jog as it only inhibits code from running. I did something similar a while back, looking at the state of Input 1 and shutting off the Jog control if it was active, that way no jogging or code could run but I much preferred the way I do things now.
BTW would the enable signals not be a better way to enable your drives?
Hood
Re: Do not allow any movement until servo drives ready
« Reply #4 on: November 13, 2011, 03:08:31 PM »
Not so much time, but probably 6 seconds.
The issue is that looking at the state of the drives would 1st prevent jog movements and 2nd inform and stop mach3 (for example during cutting).
Input1 + disable jog, can probably be a solution. Must take a look on it.

--> BTW would the enable signals not be a better way to enable your drives?

sorry, do not undestand this one. What enable signals?

thank you

Offline Hood

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Re: Do not allow any movement until servo drives ready
« Reply #5 on: November 13, 2011, 03:13:41 PM »
You have enable outputs from Mach. You can use 1 to enable all the drive (by paralleling it)  or use as many as you wish, there are 6.
They are worked via the reset condition of Mach, ie Reset not flashing and enables are active, reset Flashing and enables not active.
Hood
Re: Do not allow any movement until servo drives ready
« Reply #6 on: November 13, 2011, 04:29:55 PM »
I had the exact same issue a while back using GECkO drives and servos. I know the lag you are referring to and went around and around with it. I finally came up with a set of complicated brains to fix the issue. I now have a custom LED under the start button that lights for 5 sec after any of the axis' are enabled for any reason. The brains are very complex and too a huge amount of time to develop but work very well and so far have been error free in all conditions. I had an old post on here about the problem but never posted the brain files. Let me get the files up to my server and I'll post a link for them.

The brains use a number of user leds however only the final output one really needs to be on screen. I have 4 axis' XYZA setup but the code could be copied to add more if needed. Each axis has it's own brain and then one for the status LED. Basically it's a dwell for the drive enable.
Re: Do not allow any movement until servo drives ready
« Reply #8 on: November 13, 2011, 04:48:45 PM »
A couple of notes on the brains. First each drive (axis) has it's own enable output. X=enable1, Y=enable2, Z=enable3, A=enable4. This allows each axis to be enabled separably and each will delay the movement of the of itself without effecting the other axis'.

Each axis brain also has it's own user led. These can be added to the diag screen if desired but is not required.

The EnableLED brain give a status LED if any of the axis' are in delay. This LED is the one you want on screen.

I hope this helps.
« Last Edit: November 13, 2011, 04:50:51 PM by DamonJones »
Re: Do not allow any movement until servo drives ready
« Reply #9 on: November 13, 2011, 05:05:51 PM »
Thank you Damon, but I already have the leds on the screen, one for each axis also (led says servo ok or not).
What I am after is to control mach in a way that if any of the leds are off (any drive not in ready state) mach would not allow any movement (jog, mdi, or run file).
Neverless I will take a look on your brains ...

Will mach ver4 have convencional ladder ?

Filipe