Some beginner questions about EMI. Can't seem to get away from it. I am putting the BB and the power supply in a steel box with shielded motor cables. Everything I've read it seems like we're trying to protect the Controller from EMI so should I put the BB in the steel box by itself. I've also heard about how bad USB s are so I've been using WIFI, what's the best the interface? Well this is a start I am taking every apart and trying to stop and avoid as much EMI as I can. Almost forgot how close can wires be to each other. I am going to run the motor wires together and the limit switches together maybe use them just to home. Thank You
Absolutely the opposite. Find the source of the interference and fix that! Whatever is creating so much EMI should be brought in line. Can't hide everything from the bad guy, resolve the single source bad guy instead VFD in the mix? Usual suspect docs:blackbox-x32:faq-emi [OpenBuilds Documentation]
Sorry I did not list what kind of machine I am using. 1010 lead with plasma add on 32 Black Box and a 60 amp Everlast plasma cutter. I 'am new at this and don't know how to analyze the problem with different best way to set up your CNC table. Your assembly videos show motor wires and limit switch wires all go in the drag chain together and electronics mount to the frame rail then I read not to do this, its a little confusing. I am not familiar with any of the components or EMI. I believe it's the plasma cutter I've relocated the torch wires over the table and moved the plasma cutter about 12 feet away from the table electronics but now my ground clamp cable has to lengthened because it will not reach the table so I haven't tried it yet I'll do that later today. How can I be sure where the EMI is coming from without any test equipment? I just thought I would do everything possible to fix the plasma cutter issues and to add shielded wires insulate the power supply and controller wiring from EMI . Thanks again for your help Here is a picture of the angle on the edge of a hole cut.
HF inverter, or Blowback? Standard setup is fine, Plasma itself the more likely source Might be needed, but more of a last resort thing Is inverter body EARTHED (some has a little terminal screw on the back you need to tie to an earth)
Sorry I did not list what kind of machine I am using. 1010 lead with plasma add on 32 Black Box and a 60 amp Everlast plasma cutter. I 'am new at this and don't know how to analyze the problem with different best way to set up your CNC table. Your assembly videos show motor wires and limit switch wires all go in the drag chain together and electronics mount to the frame rail then I read not to do this, its a little confusing. I am not familiar with any of the components or EMI. I believe it's the plasma cutter I've relocated the torch wires over the table and moved the plasma cutter about 12 feet away from the table electronics but now my ground clamp cable has to lengthened because it will not reach the table so I haven't tried it yet I'll do that later today. How can I be sure where the EMI is coming from without any test equipment? I just thought I would do everything possible to fix the plasma cutter issues and to add shielded wires insulate the power supply and controller wiring from EMI . Thanks again for your help Here is a picture of the angle on the edge of a hole cut.
Yea same post I didn't think the picture went through I had some difficulties on my end. It's BlowBack. Just on my way to buy 5/8 copper ground rod for earth ground. Is it ok to use the house earth ground or it that what I'am trying the keep separated. Yes there is a earth ground on the bottom of the plasma cutter it wants a 12 gauge copper cable. I new that but this old age is a ***** I just forgot about it. I was trying to figure out if I want to go through the floor in the garage it's post tendent, cables something like every 18" then torqued to like 250' /lbs, or put a rod outside and just connect it when I'am running the plasma. I'am in AZ so I hope I have just plain sand and not the concrete kind can't remember it's name. When they say don't have wires touching just how close can say the motor wires in the drag chain? Thanks well it's starting to cool off here only 101 degrees today should be fun. This mite make my choice easy 101 outside AC in the garage.
Honestly that question would be better answered by the Plasma's vendor - they designed in a terminal, so I am sure they'll be in a better position to help out how to tame their specific product's EMI, and what that terminal needs to be bonded to (if it has to) Plasma wires should not be near the cable chain at all! Like Swing Arm swing arm distance ideally Endstops and Motors together in the cable chain - we do all the time. Can seperate out, but its rare that thats the root cause (BlackBox and Xtension Limits have active filtering, optocoupling etc - motors wires not noisy enough to bother all that - unless you run 3rd party switches?) - if in doubt run air cuts with plasma off - EMI issues persist or not? What specific EMI issues do you see? False limits triggers? USB Disconnects? Serial Corruption?
I had USB disconnects, program not finishing but since raising the torch wires and moving the plasma away from the table just about halve way through the program the close to 90 degree edge angle goes to maybe 70 degrees you can see it in the picture. I zip tied a digital angle finder to the torch both X and Y axis It ran under 1 degree (air cut). Time to start drilling. Just to clarify do not connect the plasma cutter earth ground to the house earth ground. Thanks
Cut bevel is not EMI. Torch straight? Cable not pulling on torch causing it to go off square in mount? Then consumables changout time Ask the Plasma Inverter's Manufacturer/Vendor/Support
Well I have the hole drilled through the garage floor and the ground rod about two feet in the earth, I'am going back out in the garage today and get it at least four feet deep. Now that I have the torch cable handing over the table I'll look for cable binding and maybe zip tie the angle finder back on the torch. I'll also change the consumables and run small some cuts and call the plasma cutter people. If someone does have EMI problems Coming from thirer plasma cutter will filters or shielded cables, earth grounds and electric components put in a steel box help. Thanks
Always best to stop the source from emitting the harmful radiation in the first place... Grounding/shielding tries to stand between the source and the wire - and is not as effective as you imagine. Can help, but not a magic bullet Filters: BlackBox has all the filtering onboard already, nothing external thats really useful. Plasma inverter on a seperate circuit sometimes helps Not much - all the wires leaving the box = antennas
Plasma is 220volts on it's own breaker. Hypertherm shows stand alone earth ground rod (8feet long through garage floor) should connect to plasma and electronics connect to house earth ground and then connect to stand alone earth ground rod. Adding shielded motor wires. Thanks
