Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: djk on April 22, 2013, 12:39:26 PM

Title: External Estop Requested
Post by: djk on April 22, 2013, 12:39:26 PM

I get this from mach3 when I try to tune two of my motors 6A 7Nm. The 3d is a 6A 3.6Nm and it works fine.
Thanks for any help

Title: Re: External Estop Requested
Post by: Hood on April 22, 2013, 01:31:48 PM

Sounds like you may be getting noise from the drives. Is this servo or stepper? What kind of drives? Have you got the E-Stop and Limits wiring shielded and correctly grounded?
Hood

Title: Re: External Estop Requested
Post by: djk on April 22, 2013, 02:17:16 PM

I have KINCO 2M2280N High voltage stepper drives. No limit switches yet

Thanks

Title: Re: External Estop Requested
Post by: Hood on April 22, 2013, 02:21:02 PM

Are you using the parallel port or do you have something like the SmoothStepper?

Hood

Title: Re: External Estop Requested
Post by: djk on April 22, 2013, 03:17:32 PM

Parrallel port with a PMDX 126 breakout board, inline filter for the pc

Title: Re: External Estop Requested
Post by: Hood on April 22, 2013, 04:55:55 PM

Ok try putting 2000 in Debounce Interval on the General Config page.
If that helps reduce it as low as you can.
Hood

Title: Re: External Estop Requested
Post by: djk on April 22, 2013, 05:42:50 PM

Thanks I will try it tomorrow morning

Title: Re: External Estop Requested
Post by: djk on April 23, 2013, 06:12:04 AM

Hi Hood

I started with 2000 but have reached 20 000 for the moment.Will this be a problem or would it be better to change my drives

Thanks

Title: Re: External Estop Requested
Post by: Hood on April 23, 2013, 07:05:09 AM

That is a lot and means you have a serious noise issue.
The thing to remember is low voltage signalling (5v) which people tend to use with Mach, is that there is not much potential difference between a high and a low signal, somewhere about 2.5v and thus noise can easily cause issues. Much better to have 24v signalling but that is not so easy to accomplish with the standard breakout boards available although that is slowly changing as people realise why Industrial machines use 24v I/O.

Anyway when you are using 5v signalling you have to be particular about shielding, stepper motor wires should be shielded, all 5v signal wires should be shielded and really even power wires should be shielded. It is not enough just to have a shield, that shield has to be properly grounded and usually that means just one end and all shields should be routed to a single ground point (Star Grounding)


You may get away with just shielding your E-Stop and making sure any high voltage cables are routed as far as possible away from signalling wires.

Hood

Title: Re: External Estop Requested
Post by: djk on April 23, 2013, 12:23:47 PM

Im up two 50 000, so decided two check all my wiring.Took the earth off the machine, got a spark, so tested the 3 motors ,30vac 60vac and 70vac between the motors and earth.I dont think this is normal ?

Title: Re: External Estop Requested
Post by: Hood on April 23, 2013, 01:46:12 PM

Doesnt sound normal to me, check your wiring to make sure there is no breakdown in the isolation of the wires.
If not then could well be internal insulation that is breaking down. Not sure if it is safe to test a stepper with a megger or not, dont see why not but wouldnt like to say for sure. If it is safe and you did get one to test then that would tell you if the insulation in the motor is breaking down.
Hood

Title: Re: External Estop Requested
Post by: djk on April 23, 2013, 03:31:30 PM

These motors were bought two years ago new and wired up for testing a week ago ???
Sanyo Denki $$$  :'(

Title: Re: External Estop Requested
Post by: Hood on April 23, 2013, 04:21:28 PM

Shouldnt be the motors then, well suppose you can never say never but Sanyos are good motors so its unlikely. Check your wiring thoroughly and if its not that then it may be the drives.
Hood

Title: Re: External Estop Requested
Post by: djk on April 24, 2013, 10:54:28 AM

Tested one of the motors its ok. the stepper drives are at fault?

Thanks for your help

David

Title: Re: External Estop Requested
Post by: Hood on April 24, 2013, 02:41:43 PM

something definitely sounds amiss, where the problem is I wouldnt like to say but it does seem you have some sort of leak to earth.
Hood

Title: Re: External Estop Requested
Post by: djk on April 26, 2013, 03:48:14 AM

Ripped every thing out of my control box and tested the drives.
I have 100VAC on the earth and 230V on R+ of the motor connection. ( the 3 drives )

Title: Re: External Estop Requested
Post by: Hood on April 26, 2013, 08:28:31 AM

Where are you measuring this voltage, earth to frame of drive?
Hood

Title: Re: External Estop Requested
Post by: djk on April 26, 2013, 09:33:48 AM

Earth mains to earth of the driver (PE)
The driver is on a wooden board pluged in to the mains no motors or BOB

Title: Re: External Estop Requested
Post by: Hood on April 26, 2013, 01:27:32 PM

That certainly doesnt sound right to me, quite dangerous in fact.
Hood

Title: Re: External Estop Requested
Post by: stirling on April 26, 2013, 01:34:27 PM

If you are correct (not suggesting you aren't) and you have 100Vac on the PE (earth) connection of your driver and if the driver is in a metal case (which hopefully it is) then I assume you have 100Vac on the case too. This is generally not a good thing.

As far as you're thread title goes - personally I'd say that's the least of your problems. If it were me I'd turn that puppy off right now. Zapp Auto sell them so it may be worth having a chat with them, but my guess FWIW is they're a) banjaxed and b) dangerous.

Ian

Title: Re: External Estop Requested
Post by: djk on April 26, 2013, 01:44:34 PM

Yep I have very nice rubbish bin in my garage