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Offline Sage

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Abnormal Condition warning
« on: October 17, 2008, 09:13:24 AM »
I generated some G-code which causes the "Abnormal Condition" warning light to flash on the Mach control panel. If I clck on the warning light it lists the problem as "Exact Stop vs CV mode".
The code runs ok.
I  created an offset in lazy cam on something that had square corners. It insisted on rounding the corners so instead of fighting with it I accepted it's code any way and then fixed it up myelf by hand to remove the arcs it generated and replaced then with straight moves. Not sure if that led up to this problem.

Is this warning something I need to be concerned with.

Sage

Offline jimpinder

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Re: Abnormal Condition warning
« Reply #1 on: October 17, 2008, 09:30:24 AM »
You must decide whether you are running in Constant Velocity mode (CV) or in exact stop mode - and you can switch between the two in General Config.

Exact stop means what it says. At the end of each line of code, the axis all come to an exact stop. The next line is computed and then all axis start again.

If you require square corners then you must run in Exact Stop.

In Constant Velocity mode, the next line is already calculated, and as the axis are slowing down at the end of the line to come to a stop, the next line is introduced and the axis simultaneously accelerate into the next line.

You can see, therefore why square corners are not possible with Constant Velocity.

You must, therefore, set your computer to do whichever you wish before you start. Constant velocity is the default setting (I think)
 
Not me driving the engine - I'm better looking.

Offline Hood

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Re: Abnormal Condition warning
« Reply #2 on: October 17, 2008, 09:58:35 AM »
That abnormal condition button is a royal PITA as far as I am concerned, its kind of like the wee boxes that pop up in windows and say Are you sure you want to do this. They just get the user panicking as they think there is something wrong. In Mach your default setting will be set to CV but because your code has a G61 in it it changes to Exact Stop mode and Mach sees that as an abnormal condition which in reality it is not. Your code may then have a G64 which will change things back to CV and may bring up another warning if you tell Mach that ES is the norm.

Hood
« Last Edit: October 17, 2008, 10:00:32 AM by Hood »

Offline Hood

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Re: Abnormal Condition warning
« Reply #3 on: October 17, 2008, 10:02:13 AM »
Oh and jim, square corners are possible with CV if your code arcs round at the cutters rad ;)

Hood

Offline Sage

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Re: Abnormal Condition warning
« Reply #4 on: October 17, 2008, 01:31:14 PM »
Thanks guys. That's good insight as to what Mach is "thinking".

After trouble shooting step by step (inserting m1's here and there) I found a couple of places causing different "abnormal condition" warnings. (I'm a rookey at Gcode so go easy on me).
 The one about CV seems to come and go. The last time I ran the program it was being generated while the code was drilling. Maybe the look ahead nature of the program execution is confusing the real line that is causing the problem but there are no arcs being cut until  quite a while down in the code from where the light comes on.

The other one seems to be caused by a bit of code something like this. (I think it's acceptable - no?)
G91
G0 Z-.020
G90

The light turns on for the G91 line and goes out on the G90 line. Under normal feed rates it just flashes briefly going un-noticed mostly.
The error reported in this case is "G90 / G91 State".

I'll attached the code. I'd appreciate your comments.

You'll probably want to change all the feed rates to 10 instead of 1 unless you like watching paint dry.
The CV error is visible near the beginning of the program during BOTH of the drilling sequences.
I left some M1's in the code to stop during the "G91 / G90" problem in the outline milling subroutine at the bottom.


Sage

« Last Edit: October 17, 2008, 01:40:06 PM by Sage »

Offline Hood

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Re: Abnormal Condition warning
« Reply #5 on: October 17, 2008, 04:36:19 PM »
Best thing to do is remove the button from your screenset then you wont get it blinking at you, I dont have one on my screen so never have to look at it telling me I am abnormal ;D
Hood

Offline RICH

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Re: Abnormal Condition warning
« Reply #6 on: October 17, 2008, 05:13:14 PM »
I have been ignoring that screen since the first day it winked at me.

So what or when should someone pay attention to it?

The question may sound dumb, but, if all works for me.....no problems ..... just don't even take time to read it anymore!
 
RICH

MODIFIED POST / COMMENT: Change to my thinking, i will pay attention to it, read it, and use it as a tool to refine my skills and
                                          knowledge of what i am doing.  ???
« Last Edit: October 17, 2008, 05:30:48 PM by RICH »

Offline Hood

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Re: Abnormal Condition warning
« Reply #7 on: October 17, 2008, 05:31:26 PM »
Rich, I never even knew that button had been added to the screen until maybe 6 months after it had been  as I used my own screenset. I decided  I better look at the standard screen to see what everyone was talking and worrying about, decided there and then that I would not add it to my screenset ;D
Hood

Offline Chip

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Re: Abnormal Condition warning
« Reply #8 on: October 17, 2008, 06:28:53 PM »
Hi, Rich

Art posted this, Not sure if theres a complete list anywhere.

Also, two new features are added. The Diags screen shows a mathmatical
formula of your work coordinates showing how your end coordinate is being
derived, Work Offsets, tool offsets anf G91 offsets are all shown in a talley
baord to show what offsets are in effect.

A new condition monitor has been placed on the main screen. It will not
activate any monitoring until set.

To set your "abnormal condition" monitor. You need to have your machine in the
state you consider most normal. This is in terms of the status of various things
like "are the axis homed?", "Is the unit OffLine or online?", "is it set to mm's
or inches?"," Is IJ Mode incremntal or abs"...etc..

In other words have your machine in the condition you consider to be
"Normal". Then, double click the "Condition" monitoring Icon on the main
screen. Your system from this point forward will flash "Abnormal" if certain
things are changed. Lets say you set the monitor when you were in mm's. If yu
now execute a G20, or switch to Inch mode in any way, the abnormal light will
begin to blink.

Abnormal does not mean you have a problem. It is just a way to see, at a
glance, that your machine is not in a state that you normally use. Its a visual
warning that you maybe should reset whatever is different when this job is done
so next time you use it you dont get surprised with starting a job in mm's, when
your used to inches because the last job changed it on you. To find out
specifically whats changed, just click once on the "Condition" Icon. A tip box
will come on for 3 seconds to tell you whats different..

Remember, an "Abnormal Condition " alert does NOT mean your broke or have
anything to fix, its just telling you that something important to you may have
changed. To shut off the current warning, just double click it and reset it to
believe that current conditions are "normal". Current "Normals" are saved in
the profile, so each profile can have a different meaning as to what it
considers Normal..

My thanks to John Prentice and Olivier for their work in both "Condition
Monitoring" and calculation formulas onscreen as telltales to the user. I have
shamelessly stolen both ideas, and implemented them in the core code as I think
they are excellent troubleshooting aids.... :-)
Thanks, Art
www.artofcnc.ca

Chip

Offline RICH

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Re: Abnormal Condition warning
« Reply #9 on: October 17, 2008, 08:30:39 PM »
Good info Chip,
With intent understood it makes for easier acceptance.
Wonder if it will be automaticaly added to the lathe screen later on.

Maybe it should be an "option" to  implement via configuration.
RICH