Well I grounded X2 to the main ground and when I started LinuxCNC and started to home I got the flurry of sserial errors. So I thought about it for a bit and maybe the ground from the computer case to the ground block was creating a ground loop so I took it off. Started LinuxCNC and immediately go a flurry of sserial errors which locks up LinuxCNC. Mind you this is with the 7i77ISOL card between the 5i25 and the 7i77 which is supposed to block any noise in the sserial communications. The X2 to ground has to go...
I do have a 7i92 to test out... JT On 1/2/2016 6:26 AM, John Thornton wrote: > I do have a "control transformer" which can be identified by the three > fuses on top. One for X1 (secondary) and one each for L1 and L2. I > went back and found out which was X1 and X2 and will correct my wiring > today. My question is I have a filter on X1 and X2 should I ground > before or after the filter? > > JT > > On 1/1/2016 6:41 PM, John Kasunich wrote: >> 120V transformer secondaries (in the USA) need to be grounded on >> one side, even if they are part of a machine control panel. >> >> Such transformers are referred to as "control power transformers" >> and traditionally powered electro-mechanical control devices such >> as relays and contactors. Today they still power those things, and >> they also power AC-to-DC supplies that run the electronic parts of >> the control. The low voltage DC power distribution (typically 24V) >> is sometimes un-grounded, sometimes single-point grounded, for >> exactly the noise reasons Berthos mentions. But the 120V "control >> power" isn't used a the "reference" for anything - it is still "dirty" >> power, although not as dirty as the main power that might be going >> to a VFD or whatever. > > > > ------------------------------------------------------------------------------ > > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
