Remember Arc Lost position

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Re: Remember Arc Lost position

Postby cncdrive » Thu Oct 27, 2016 8:41 pm

Robertspark wrote:
Robertspark wrote:I think terry is implying intergrate thc within the uc300.... problem is.... analogue input not fast enough or not high enough bit resolution....

What about spi interface with the MCU for thc add-on board with higher analogue sampling (2 channel, 16 bit)....


Sorry parallel discussions....

There was a post from Balazs on 6thoct

About the analogue inputs on the uc300... hence my suggestion about spi, and external high speed and resolution spi (monitoring the isolated 50:1 side... )

viewtopic.php?f=2&t=27&hilit=Analogue&start=30


OK, but why to involve analog inputs when a dual $0.5 comparator or a window comparator can do this job?
The rest of things like the delay after arcOK signal is implemented inside the software, so no need for complex logic at all.
One comparator for the ArcOK and another for the setpoint.
I don't see a difference in comparion as if the analog inputs where used other than that the setpoint could be then controlled by software,
which could be still implemented in a digital way, just it requires a few more external stuff then.
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Re: Remember Arc Lost position

Postby Robertspark » Thu Oct 27, 2016 8:56 pm

The advantage is being able to set the setpoint and any hysterysis internal within the uccnc software.....
(could do setpoint via modbus if external hardware.... but just sounding out what is possible?)

then there is stuff like gap detect (rate of voltage change)

I'm sure Terry, Keith and Andrew could list a whole load of other functions.
Rob
Einstein ― “If you can't explain it to a six year old, you don't understand it yourself”
...working my way through the 1000+ ways things don't work to find the one that does
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Re: Remember Arc Lost position

Postby cncdrive » Thu Oct 27, 2016 9:25 pm

Rob,

Sure, if the external hardware which sets the setpoint talks modbus then you could send that information via modbus.
You could add a DRO and make a modbus function which sends the values and make a macroloop which fills those modbus registers which are sent by the modbus function.
Or you could build a plugin and do the same from the plugin instead of macroloop.
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Re: Remember Arc Lost position

Postby Vmax549 » Thu Oct 27, 2016 10:55 pm

HI GUYS I can already do external THC sensing with modbus. RazorDanceTHC.

The idea was to put everything internal into teh UC300eth chipset so you would NOT have to do anything with plugins or buy a $$$ THC card to make it all work.

With the CSlabs controller all you do is feed in a 0-5v analog signal. The controller then handles everything else and all communcations from Mach3/Controller are handled internally through teh ethernet link.

This would put UCCNC very high up in teh food chain of DIY CNC plasma controllers.

BUT it may make other THC's obsolete at teh same time. SO I guess there is a balance to be struck between UCCNC and THC OEM's ???

(;-) TP
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Re: Remember Arc Lost position

Postby Robertspark » Thu Oct 27, 2016 10:57 pm

Rob
Einstein ― “If you can't explain it to a six year old, you don't understand it yourself”
...working my way through the 1000+ ways things don't work to find the one that does
UC400eth, UC300eth, UCCNC v1.2105, Neuron Lite
UCCNC v1.2105 Macro Manual
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Re: Remember Arc Lost position

Postby beefy » Sat Oct 29, 2016 4:26 am

Guys,

just a thought here. Is it good to mix up focus like this inside one thread ??

We've went from quite a concentrated focus on mid cut restarts and torch refire after a flameout, to talking about implementing a THC fully in the UC300, etc (which I think would really increase sales for plasma use).

I feel we were really getting to the core of the matter on the flameout matter before attention was diverted to the THC suggestion. That happened in a previous thread which simply led me to create a new thread on the matter that WAS at hand.

I'm looking to do the same here ?? correct me if I'm wrong.

Keith.
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Re: Remember Arc Lost position

Postby Robertspark » Sat Oct 29, 2016 6:48 am

Sorry, I think it was me.

But reading the thread again, I thought it was time to write or review a macro or two and try a few restarts, and report findings. I was going to have a look at how it may be possible to back up one line of gcode (motion) at a time, and try to flag up if the previous gcode line was a non movement line command (such as g4, m3, touchoff (m1031 for me), thc enable (m206) etc ).... as there is no point at back stepping through those commands one line at a time..... that was my thoughts at the time on this subject.


Instead of starting a new thread, it may be worth bringing it back on track.

(There is a separate thread asking for specs on the analogue inputs)... that is really all we can do as users... up to cncdrive if they want to develop that (hence me providing all the info I can in that thread)

(There is some logic to this although it's hard to have a thread follow purely one topic when lost arc operation is affected by thc a bit)
Rob
Einstein ― “If you can't explain it to a six year old, you don't understand it yourself”
...working my way through the 1000+ ways things don't work to find the one that does
UC400eth, UC300eth, UCCNC v1.2105, Neuron Lite
UCCNC v1.2105 Macro Manual
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Re: Remember Arc Lost position

Postby Robertspark » Sat Oct 29, 2016 7:06 am

Also, I had another thought about (trying to, haven't got a clue how yet) evaluating the current line of gcode relative to the direction of tradjectory .... then backing up and storing an m10 position 10mm before the lost arc position (adjustable relative to feedrate at time of lost arc).... and then backing up to a restart position to allow the flying start....

I'll write how I thought about doing this later.... not sure about if you had a lost arc issues where the current line was g02/g03 though....

I hadn't finished on the topic I just needed to put pencil to paper and get next to machine.... plus I wanted to sort my m3+m10 OR/AND gate hardware solution which would be required for lost arc restart testing.
Rob
Einstein ― “If you can't explain it to a six year old, you don't understand it yourself”
...working my way through the 1000+ ways things don't work to find the one that does
UC400eth, UC300eth, UCCNC v1.2105, Neuron Lite
UCCNC v1.2105 Macro Manual
Robertspark
 
Posts: 776
Joined: Sat Sep 03, 2016 4:27 pm
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