Ok - I will say a couple more things and then shut up about it. :) - On conventional machines (not robot arms or such) the linuxcnc soft limits are rock solid. After the machine is homed - they work 100%. (again - I have never hit the limit switch when the machine was homed) If you may be used to another machine control software which shall be unnamed which may not be as consistent - you don't have to worry about it.
- It really is a safety thing. what happens if the servo drive runs away towards the limit switch? (encoder failure or some such failure mode) Do you really want the servo drives enabled still when it hits the physical limit switch? (I know I want the estop to trigger and kill power) Your Cincinnati isn't a hobby machine run with small steppers. You probably have tons of force that would slam into the hard limits - then maybe smoke other things.. - You could setup a button that then allows you to enable the drives to jog off the limit switches. (again - it should happen never) sam On 2/12/2013 10:03 AM, Pete Matos wrote: > Well that may work fine for you and honestly I love soft limits as much as > the next Guy but I honestly prefer to have the drives enabled in a limit > switch trip situation so I can just backoff,backup and punt my way back > into the program. It worked fine that way on my RF45. If I have my way I > will have both hard and soft limits working continually and the estop > shutting down the show in an emergency situation. So I appreciate all the > ideas here but can we kinda keep the ideas pointing in that direction so my > already befuddled mind does not get any more befuddled than it has to be. > LOL thanks guys....peace > > Pete > > > > On Tuesday, February 12, 2013, sam sokolik <[email protected]> wrote: >> We have a brake on the y axis also. Yes it is a pain. :) I should >> disable the jog until after the machine is homed. Problem fixed. :) >> >> sam >> >> On 2/12/2013 9:43 AM, Pete Matos wrote: >>> That would be a real bitch to have to back off a millhead on a VMC off a >>> limit with a motor brake installed... >>> >>> Also as per the complete power down issue, having been ringside when > my >>> Y axis drive blew and watching the bright white light coming from behind >>> the machine I was VERY glad the estop circuit cut all power to the drives >>> LOL....yeah I am good with watching the spindle coast to a stop any >>> day....peace >>> >>> Pete >>> >>> On Tuesday, February 12, 2013, sam sokolik <[email protected]> > wrote: >>>> My axis limit switches are hooked directly into the estop loop. I have >>>> soft limits setup. The only time I have ever run into the over-travel >>>> limits was when I was jogging before homing (not paying attention... ) >>>> (and yes - I have to back off the limit manually) >>>> >>>> sam >>>> On 2/12/2013 9:07 AM, andy pugh wrote: >>>>> On 12 February 2013 14:53, Pete Matos <[email protected]> wrote: >>>>>> Thanks for the info...can you explain that last part 7i77 GPIO? >>>>> The 7i77 has 32 inputs and 16 outputs for general-purpose IO. (on TB7 >>>>> and TB8 I think). >>>>> >>>>>> Did I hear you correctly when you said you wired your limits and >>>>>> homes in series and in with the estop circuit? >>>>> No, as you say that would cause problems with backing off of a limit >>> switch. >>>>> In actual fact the machine I am describing doesn't yet have limit >>>>> switches, it is a bit of a slow-burning project. They are likely to be >>>>> added fairly soon, though. >>>>> However, my intention is to keep them entirely software-controlled. I >>>>> would be interested to hear opinions on the advisability of this. >>>>> >>>> > ------------------------------------------------------------------------------ >>>> Free Next-Gen Firewall Hardware Offer >>>> Buy your Sophos next-gen firewall before the end March 2013 >>>> and get the hardware for free! Learn more. >>>> http://p.sf.net/sfu/sophos-d2d-feb >>>> _______________________________________________ >>>> Emc-users mailing list >>>> [email protected] >>>> https://lists.sourceforge.net/lists/listinfo/emc-users >>>> > ------------------------------------------------------------------------------ >>> Free Next-Gen Firewall Hardware Offer >>> Buy your Sophos next-gen firewall before the end March 2013 >>> and get the hardware for free! Learn more. >>> http://p.sf.net/sfu/sophos-d2d-feb >>> _______________________________________________ >>> Emc-users mailing list >>> [email protected] >>> https://lists.sourceforge.net/lists/listinfo/emc-users >>> >>> >> >> > ------------------------------------------------------------------------------ >> Free Next-Gen Firewall Hardware Offer >> Buy your Sophos next-gen firewall before the end March 2013 >> and get the hardware for free! Learn more. >> http://p.sf.net/sfu/sophos-d2d-feb >> _______________________________________________ >> Emc-users mailing list >> [email protected] >> https://lists.sourceforge.net/lists/listinfo/emc-users >> > ------------------------------------------------------------------------------ > Free Next-Gen Firewall Hardware Offer > Buy your Sophos next-gen firewall before the end March 2013 > and get the hardware for free! Learn more. > http://p.sf.net/sfu/sophos-d2d-feb > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users > > ------------------------------------------------------------------------------ Free Next-Gen Firewall Hardware Offer Buy your Sophos next-gen firewall before the end March 2013 and get the hardware for free! Learn more. http://p.sf.net/sfu/sophos-d2d-feb _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
