Estop

[HuFlungDung]

I don't make a habit of using the ESTOP button, but I would like to make mine work better than it does currently.

Basically, what bugs me is all the Galil card "BGS" errors that keep coming back through the Camsoft interface when I hit Estop during either a single step move, or in continuous mode. These errors will never stop coming if I keep answering "No" to the "Do you want to close program" dialog that pops up. When I release the ESTOP button, then the messages will quit.

So, if the Estop is still activated, I answer "No", because I do not want to close the program, that is where I want the pestering to end. Instead, it re-reads the ESTOP.fil logic again and asks me again the same question.

So, how to break this endless cycle? Should I issue a STOP command inside the ESTOP logic so that CNCPRo stops sending old movement commands to the Galil?

Finally, how to bring the motors back online after an ESTOP has been cleared? A this point, the servo amps are showing a stop condition, but I am not clear on how to reset them within the Camsoft controller.

~@~ESTOP.FIL
IF#16=1THENSPINSTOP
#28=0:#29=0:#30=0:#24=1:#25=1:#26=1:#27=1:SLEEP .5:#24=0:#25=0:#26=0:#27=0
\316=1 'flag for Estop button logic in inputio.fil
TIMER OFF
SPINDLERPM \57 ISPLAY5 \57

[Al_The_Man]

Generally the philosophy behind the E-stop circuit has been for initially the protection of the operator, followed by protection of the machine itself, if one is building/retrofitting a machine for one's own use then pobabally anything goes, but if you are retro-fitting for a customer or have employees that are going to use the machine, then it would be a wise decision to look at the state & provincial codes and recommendations for legal reasons.
In the states there is the OSHWA and the NFPA regulations to consider, in Canada, there is usually Provincial regulations.
Going back to the original question, I tend to stick with the NFPA guide lines and use hardwired E-stop control and have software input to acknowledge the E-stop, rather than have the E-stop software originating it , which goes against the code.
First I set up an E-stop relay circut that has contacts to switch the servo amplifier-enables as well as remove the amplifier power, this relay would also control the spindle, and depending on what type of spindle would depend the degree of control i.e. standard AC induction motor, DC or AC Electron control or VFD. all require a different approach.
I also include the Watchdog relay on the Galil card in the E-stop string and the amp enable outputs on the Galil can be included AMPENX,Y,Z etc , Also I use the E-stop relay to switch off the power to all the logic outputs, the inputs I keep powered for diagnostic purposes especially if these are low voltage (5v to 24v ) type.
An input (e-stop) can be fed into the logic indicating a E-stop exsists, which inturn would be included in the FeedHold logic. And any other logic that was deemed necessary including issuing a Alarm message.
In some amplifiers such as DC & AC servo's, removing the DC power is not always sufficient to stop the servos as the DC supply remains charged for a period of time and can allow servo movement until the DC has decayed, that is the reason for also using the amp enable signals which most amps have.

Remember in an emergency the E-stop button is smallest button on the panel
Al

[HuFlungDung]

Thanks for your reply, Al.

But the problem I was outlining was not actually a problem with getting ESTOP to function. It already does stop everything, etc. It is just getting the machine back into working mode without shutting down the controller is a bit of a hassle, because of what I described happening. It is also a problem to stop the machine from continuing the program immediately after the ESTOP is removed.

I'm using version 14-7 CNC professional if that has any bearing.

Its as though the command buffer is continually trying to send a motion command to the card while the Estop is in effect. Because the drives are disabled, I believe the Galil error comes back through the Camsoft interface.

If anyone has a sample ESTOP.fil or relevant inputio.fil logic that they would like to share that provides for a smooth ESTOP and recovery from ESTOP, I'd like to see it.

Thanks in advance.

[Al_The_Man]

Hu, I still think you are better not to rely to heavily on the estop command, I do not have the professional, only the lite + bonus, but the manual does mention a method of E-stop that resets its current location and does not finish the move, by using the abort input on the Galil card, If you want to reset the amps, what type are they? and how are they hooked up right now, is there any interface to the Camsoft/Galil apart from the command signal?
Al

[Thermwood]

Hu,

On our router, we've kept the E stop (actually one in cabinet and oneon face) hard wired to a contactor which drops power to the amps.
We use it a lot between cycles, when the machine is powered but unattended for safety ...
Obviously it does not stop the galil and information continues to flow, until the galil reads an error from the amps...

When trying to interrupt a cycle, then resume, I would use a feedhold command, then push the Estop button in if necessary. Esc also works but we've had problems when hitting esc while machining an arc. It seems that the controller jumps directly to the next line after the arc on resume ..
It works ok with linear moves ( I don't like it because it interrupts the motion brutally and causes the axes to jerk)


Feed hold seems to be your best bet to interrupt and resume cleanly....
I wonder if you could add a feedhold command at the beginning of your estop command ....

[HuFlungDung]

Thanks Pierre.

Sorry guys, I discovered I pulled a real blunder here

I discovered that I had only been using the STOP command instead of ESTOP in my inputio.fil. This has been the case for the last 23 backups of my file, and before that, it was cnc lite.

There may have been some reason why I used only the STOP command then, but I've forgotten what it was now.

Without the ESTOP command being read, the contents of Estop.fil never gets read!

So, with that fixed, there is far less trouble. The STOP command would of course, have stopped all the motors, but not the program in sequence. This resulted in the Galil error coming back through because it could not execute with the motors stopped.

Now, after Estop, there are no annoying messages, however the motors are still off, even when the Estop button is released. At this point, I have added an operator message to hit the Escape key. As soon as the shutdown dialog comes up, the motors turn back on, and I can cancel out of the shutdown.

The machine remembers it position, so after a simple return to home position (not the homing routine), I am up and running again.