Another limit switch Q.

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edclayton1
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Another limit switch Q.

Post by edclayton1 »

I have a series of limit switches connected in series to my blade runner controller table I/O card and am running CommandCNC. When I activate any of the limit switches I can see the LED turn on in CommandCNC and on the Table I/O card if I take peek at it. But the switches are not actually stopping motion in my CommandCNC when they are lit and the switches are being made. I have seen this on my two machines that I have and I have verified that they are selected in the configurator application to be limit switches but it still does not seem to work correctly for me. Any thoughts? I did make sure that the start up icon is using the correct configuration of the configurator for the settings to work. I just cant understand why the LED's in the Diagnostics screen indicate they are working then why are they not stopping the axis from moving? I have searched the internet hi and lo but cant seem to find any answers to this question. I usually don't need them but it just kind of drives me bats that they wont work. :P
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tcaudle
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Re: Another limit switch Q.

Post by tcaudle »

1/ If the lights come on in the Diagnostics WHEN a switch is tripped than make sure it is turning on the LIMITS Inputs in the diagnostics.
Now , if that is all of your limits then assign the LIMITS Input to the "all Limits " Function. Do not co-assign any of the other switches to be Homes AND limits. You cannot have both ALL limits and then "other limits". The latest release of CommandCNC (0.9.7) adds some more options to the INPUTS in the Configurator . One significant add is that you can now have mote than one E-Stop function so EITHER one going active will cause an E-stop event.

90% of the battle its to get the signal into CommandCNC . the reset is assigning the NAMED Input to a Specific FUNCTION. The EPE/EStop INPUT on the Table I/0 is designed to be used with an external switch and its the only input hardwired to the internal circus that senses the Motor Power is ON. that is why you cannot come out of E-Stop if the motors and not powered up and it puts the software in Estop if the ESPII box turns off power for any reason.

BTW the polarity of the INPUT should be set so it cause the INPUT in Diagnostics to come one when it is ACTIVE. That means the LIMITSor ESTOP may show a constant LED on the Table I/O but the INPUT Status should only come on when it is supposed to trip the Function Using the INVERT checkbox determines the active polarity of the signals.
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edclayton1
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Re: Another limit switch Q.

Post by edclayton1 »

tcaudle wrote:1/ If the lights come on in the Diagnostics WHEN a switch is tripped than make sure it is turning on the LIMITS Inputs in the diagnostics.
Now , if that is all of your limits then assign the LIMITS Input to the "all Limits " Function. Do not co-assign any of the other switches to be Homes AND limits. You cannot have both ALL limits and then "other limits". The latest release of CommandCNC (0.9.7) adds some more options to the INPUTS in the Configurator . One significant add is that you can now have mote than one E-Stop function so EITHER one going active will cause an E-stop event.

90% of the battle its to get the signal into CommandCNC . the reset is assigning the NAMED Input to a Specific FUNCTION. The EPE/EStop INPUT on the Table I/0 is designed to be used with an external switch and its the only input hardwired to the internal circus that senses the Motor Power is ON. that is why you cannot come out of E-Stop if the motors and not powered up and it puts the software in Estop if the ESPII box turns off power for any reason.

BTW the polarity of the INPUT should be set so it cause the INPUT in Diagnostics to come one when it is ACTIVE. That means the LIMITSor ESTOP may show a constant LED on the Table I/O but the INPUT Status should only come on when it is supposed to trip the Function Using the INVERT checkbox determines the active polarity of the signals.
I did recently update to rev. 0.9.7. The lights only come on in diagnostics when one of the switches is made. I have a sting of far, and near limits for my X and Y axis all tied together in one series loop as shown in the manual. I did reconfigure the configurator a couple of different ways and now the motion stops when a limit is reached. At first I set it up the way Maria showed me and it acted strange, then I changed the configuration slightly and then they stopped but they are now acting like software e-stops. Which is OK because at least now they are stopping and usually they should never be needed anyway.
Thanks for your help on this. I have one more issue to bother you about, but its a different topic so I guess I will start a new post for that one. I will take it over to the CandCNC forum as that is probably a better place to ask these types of questions I guess.
Cheers, Ed :?
Home Built 4 * 8 table
Bladerunner
Miller Syncrowave 250 TIG welder
Miller 211 Wirefeed Welder
Bridgeport Mill
Jet 13 * 40 Lathe
Hypertherm Powermax 65
80 gal 2 stage 175 PSI Emax air Compressor
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