HF start.... Any way to change to LF?

[lcvette]

I have been wrestling with HF interference on my PP256 and I have grounded everything very well, it wreaks havoc in my cnc equipment and has created alot of cost in trashed work pieces when this happens on mills including tooling breakage and crashes. I was wondering if there is a way to convert it over to low frequency to fix this or am i SOL?

Thanks in advance!

Chris

[Titan winch]

There is no way practical way to do the swap . The plasma uses Pilot start but needs to cut in HF . And of course HF starts Tig.
The 205 still needs HF to start Arc on tig but it uses a continous Blow back torch with no HF , To change the process even for the plasma means redesining not only the Plasma board but the Main control board so while it is theoretically possible it is no where near practical.
However shielding the cables is something that you may wish to explore.

[sportbike]

If you are referring to use during TIG welding, you should be able to switch to a scratch start or lift mode without high freq.
There really isn't a "Low frequency" mode. The HF creates a disturbance in the air, ionizing a bit of it and makes it conduct electricity, allowing the arc to jump.

[geezer]

I have been wrestling with HF interference on my PP256 and I have grounded everything very well, it wreaks havoc in my cnc equipment and has created alot of cost in trashed work pieces when this happens on mills including tooling breakage and crashes. I was wondering if there is a way to convert it over to low frequency to fix this or am i SOL?

Thanks in advance!




Chris

The solution for that is FERRITE CHOKES on your CNC equipment, the welder is not to blame, even a plasma torch will generate HF interference, check out this site: http://computer.howstuffworks.com/question352.htm for more info on how it works, Radio shack or someother outfit will have them, they just snap over the CNC cables and eliminate the HF problem.

[performance]

The 256 should NOT be used for CNC work...or at least it should NOT be considered for regular use, and only for light gauge, intermittent use.. There were some with CNC ports made, but we do not recommend them but for limited use...speaking of crashes.

IF you want that, buy the 60C with the correct start for CNC. (Inductor)

[sportbike]

The 256 should NOT be used for CNC work...or at least it should NOT be considered for regular use, and only for light gauge, intermittent use.. There were some with CNC ports made, but we do not recommend them but for limited use...speaking of crashes.

IF you want that, buy the 60C with the correct start for CNC. (Inductor)

I read it to mean the HF was causing his OTHER cnc equipment (mills) to crash, not so much a cnc plasma.

[lcvette]

ok,

I took your advise and put ferrite clamps on every wire going into the control cabinet to include:

each stepper motor cable, the Parallel port cable both ends, power cords for both the PC and the Driver box for the CNC unit, I have a 8' copper ground rod driven the full 8' down and grounded to my plasma machine and it is still kicking my E-Stop on the mill as soon as i strike an arc with the handheld plasma torch from about 20' away from the mill........ this is a nightmare. I tried the TIG TOrch and suprisingly it did not kick the E-stop.. so welding is fine but plasma cutting is a nogo. I need to be able to do both during the day as some programs i run on the mill are 8-9 hours long and haulting everything else in a fabrication shop because parts are being made can't happen.

Any other suggestions or thoughts?

All help greatly appreciated!

Chris

[lcvette]

aluminum foil will be tried, have to go get some more, didn't have enough to cover the whole thing.... will report back as soon as i try it!

Thanks and any other suggestions I am happy to try as long as they aren't hundreds of dollars (at that point i would just assume get the 60c or other brand lower interference unit)

Chris

[todmorg]

Chris, your best solution is to conncet the ground lug on the back of the unit to a low inductance, very short, signal ground connection.

Based on your symptoms, you need to stop the torch lead from acting as a transmitting antenna. One way to test this is to wrap a couple of layers of aluminum foil around the outside of the entire length of the torch lead to see if the symptoms change. I have to go but will check back later.

I agree, it is much easier to stop the noise at its source, the aluminum foil would at least give you a starting point. The foil is a shield and should only be grounded at one end to avoid ground loops and hooked to a clean ( noisefree ) ground.

[lcvette]

ok, I added more grounds all bare copper stranded wire in a star configuration bolted to each component and wrapped tin foil around the torch lead and grounded it only on the cart end. this helped but still kicked the E-stop by about the 4th torch start. it seems that it is fine if you get it cutting but the starting arc is the culprit. any other thoughts and ideas? I am quickly feeling more and more defeated and have a load of work to get out which is adding pressure to my situation.

Everlast.... Help, is there anything that may need adjusting such as the gap and if so is there a detailed description and procedure of how to accomplish this?

Thanks!

Chris

[lcvette]

I can ask around to see of someone i know, knows someone who has a spectrum analyzer, worth a try. I have tried using two different lines to power the PP256, one is the outlet i installed for it and the other was a direct run from the breaker box, both did the same thing. I also tried putting ferrite beads on the individual leads from the breaker box and still no joy. I wish i had done some more research before making this purchase.. at the time it seemed like a phenominal deal but now I wish i had gotten two seperate machines, one for TIG welding and the 60C for plasma cutting, I am sure that would have been the wiser choice and in the long run would have allowed one of my guys to be welding while I was plasma cutting or vice versa. I wonder if Everlast would be willing to work something out on that..... Will give them a call today.

Chris

[lcvette]

I concede.... it won... it isn't going to work, I have re-grounded everything in a star configuration and while it has helped it has not made it fool proof to where it doesn't crash the mill. I have contacted Everlast about getting a 60C unit which would eliminate the HF starting issue and hopefully allow me to use both machines at the same time. besides i have a plasma table as well that is going to be up and running soon and need a cutter for it. such is life....

To anyone out there who is searching and reading this, some may say that HF start can be used and i am sure it can but i would imagine more money would be spent into the grounding and shielding then it would be worth, better to get a machine that won't interfere with you electronics if you have CNC equipment. I could have bought a 60c with the time i have wasted trying to fix this unit and money in wiring, grounding rods trashed jobs on the mill and broken tooling etc... not worth it. Lesson learned.

Chris