Printable View
Hi all iv just finished build my Cnc plasma gantry and made a mistake and bought a hf start machine .... I’m currently experiencing extreme emi issues.
My question is will a pilot arc machine be a better choice regarding hf noise to my electronics and pc? ... a recent google search reveals that pilot arc reduces noise is ,how true is this?
Thanx
https://www.bakersgas.com/weldmyworl...plasma-cutter/
https://uploads.tapatalk-cdn.com/201...bb0eb12715.jpg
Sent from my iPhone using Tapatalk
Pilot arc can still use HF starting. The most common alternative to HF start is blow-back start, and it always includes pilot arc.
From what I've heard, blow-back start is much better as far as interference.
I have a question about an idea i have about a diy plasma .why couldnt a person take an old school miller hf awg -1 add add on ark starter with a pilot ark plasma torch attached instead of tig torched power by something lile a miller old school trail blazer 250g that has muiti process power options and a polarity switched on the output side of tjeQuote:
Originally Posted by skrubol
I have a question about an idea i have about a diy plasma .why couldnt a person take an old school miller hf awg -1 add add on ark starter with a pilot ark plasma torch attached instead of tig torched power by something lile a miller old school trail blazer 250g that has muiti process power options and a polarity switched on the output side of the output side of the hf box to get your torch gound polarity why wouldnt that work as awesome plasma cutterQuote:
Originally Posted by skrubol
Plasma voltages are quite a bit higher than tig voltages. Also, if you were going to use an arc starter, it would be much easier to use a traditional HF start torch I would think.
That statement in the original post is not correct.
Pilot arc is ANY plasma that has the means to strike an arc without physical touch, so that include HV AND HV/HF start plasmas.
Scratch start and blow back do not have a pilot arc so they have to make physical contact with the material. That makes them not suitable for use on CNC machines.
As for interference, that HV/HF type does create much more interference, but they can and are used on cnc machines, and so are the HV start ones.
Back to your problem,
You need to have the proper grounding and shielding, otherwise nothing will help you. A metal case for the electronics is a must, separating the cnc machine from the cutting table is also good to avoid interference if you do not have proper grounding.
I think you are confusing what pilot arc means. Pilot arc will create an arc without even having proximity to the workpiece. Because of this, it can be used on painted or rusted metal that has a non-conductive surface. The pilot arc is hot enough to burn through the paint or corrosion and then establish a direct plasma arc with the conductive workpiece underneath.Quote:
Originally Posted by tommylight
All blowback start plasma cutters I've seen are pilot arc. Also, I've never heard of scratch start plasma (doesn't mean it doesn't exist,) that's usually a term that refers to TIG.
You should really do some more reading before you accuse someone of confusing things.Quote:
Originally Posted by skrubol
https://weldingweb.com/showthread.ph...268#post211268
with regards to EMI/RFI issues we face on hf start plasma cutters I would like to understand this more in technical detail as to how exactly our control box is being effected to this problem, am I correct in saying that there are 2 ways in which our electronics are effected via hf .1 thru the air (this requires shielding of electronics like metal cabinets and shielded cables and grounding)and .2 physical contact where EMI/RFI is running thru the power lines (this requires filtering and grounding using capacitors and grounding on a electronic piont of view)
In regards to number 2 ,If what I’m saying is correct this means if I use a power source to power my electronics that is completely isolated from the power lines of the plasma machine for eg. use the neighbors power lines or a generator or a UPS then I shouldn’t have any physical contact with EMI/RFI?
Sent from my iPhone using Tapatalk
None of that is new info to me.Quote:
Originally Posted by tommylight
What do you think I got wrong?
I just want to know if a use a isolated power source for my electronics, will I be able to ditch the hf via the power lines?
Sent from my iPhone using Tapatalk