Dynasty 300 hf arc starting issues with new helmet?

[Jim Moser]

Just got a new Lincoln Viking clear view helmet but it seems more sensitive to poor arc starting on my Dynasty. It turns dark when I depress the foot pedal before the arc starts? I have always had inconsistant arc starts with this machine but it has never triggered the helmet before. I have been using an older Viking and a Miller Digital Elite. I am thinking the newer hood is more sensitive? I do not always see the high frequency with this Dynasty. Often the arc won't start when I push the peddle down, seems inconsistant but annoying at times. First I blamed the new helmet but thinking the arc starting circuit of the Dynasty is the problem. I think they have some kind of starting system that is problematic as I have seen some other users having similar problems and no solution from Miller that know of? Don't think their is points or user options except buy a new board for more than I paid for the welder.
Any ideas?

 

[52 Ford]

Just got a new Lincoln Viking clear view helmet but it seems more sensitive to poor arc starting on my Dynasty. It turns dark when I depress the foot pedal before the arc starts? I have always had inconsistant arc starts with this machine but it has never triggered the helmet before. I have been using an older Viking and a Miller Digital Elite. I am thinking the newer hood is more sensitive? I do not always see the high frequency with this Dynasty. Often the arc won't start when I push the peddle down, seems inconsistant but annoying at times. First I blamed the new helmet but thinking the arc starting circuit of the Dynasty is the problem. I think they have some kind of starting system that is problematic as I have seen some other users having similar problems and no solution from Miller that know of? Don't think their is points or user options except buy a new board for more than I paid for the welder.
Any ideas?

Isn't there a sensitivity setting on that hood?

Sent from the ENIAC using Tapatalk

 

[Bondo]

Think of high freq better on a plasma cutter. The visual arc starts but isnt cutting yet. Your new helmet is more sensitive and is detecting the HF better.

Change the settings and you'll either love or hate your helmet.

 

[Kalispel]

The high frequency is both conducted and radiated from the welding circuit. Poor ground connections and coiled cables can cause significant problems.

Check the grounding on the machine. Normally, no current should be flowing in the ground bonding wires. Welding machines often have High Frequency (HF) bypass circuits that capacitively couple the HF "noise" to the machine case which is theoretically at "earth" ground. Make sure there is a short and good bond from the machine case to the building ground. Ground the work table to building ground. Make sure the ground path is bonded properly -- do not expect stray HF currents to pass through the building structure or water pipes. Long wires and coiled wires have inductance which means they cannot effectively conduct HF currents. Having the electrical feeds in metal conduit is best.

Some people insist on grounding rods driven into the earth in the vicinity of the welding machine. Your building will have one of these near the power distribution box. The idea is to tie the neutral reference of the building power circuit to "earth ground". The earth has a relatively high impedance so it is not good practice to push current into a grounding rod. But, in the case of high frequency current, the earth provides a short and good path to dissipate the HF energy. The earth is "lossy" meaning the energy will be dissipated instead of reflected. I have seen it work but it is also a bit of engineering voodoo.

Uncoil the welding cables and lay them neatly with the torch and work cables together. This minimizes stray inductance that will impede the HF signals. Separate the control wires (foot pedal) from the welding cables to prevent HF from coupling into them.

 

[gary-sc]

Jim, I agree with others that the helmet sensitivity is probably causing your problem. But, to your other problem my Dynasty does this once in a while, blowing out the machine helps, but in the moment if it's not striking an arc I touch the tungsten to the metal (pedal off) lift the tungsten and strike the arc. I've never had that trick not work in 12 years of having the welder.

Hope that helps

 

[Jim Moser]

Yea Gary I have noticed that touching the tungsten helps it start again but dissapointed in Miller as my old synchrony never ever had this problem. I did try turning the sensitivity in the hood to high and got flashed so not crazy about that option. The clarity of the hood is awesome though and no issues mig welding just the HF or whatever Miller invented and calls it an improvement.

 

[turnworks]

Crank the start amps to 15 for 90ms while keeping the min amps at 1-2. Just a little bump on the pedal will give a nice pop to get the arc going consistantly. The settings are under the nonsecret secret menu on the DX models.

Not sure what dynasty version you have so you might have to pull out the manual to find the settings.

You are correct some of the newer helmets sense the HF and go dark before the arc even happens.

 

[Jim Moser]

Thanks turnworks, I found those settings and tried them, seemed to help when I had the max amps set to 300 but tried it today with small job with 200 amp start amps and couldn't get the arc to start after 6 or so tries. I don't see any hi freq but the helmet must see something as it goes dark. Touching the tungsten didn't help either. I used the settings you suggested, but not sure what they do so I dont feel like just cranking them up without a good reason. Pretty dissapointed in a Miller $6,000 plus welding machine. I noticed this problem when I first got it but not consistently.
Jim

 

[turnworks]

There will be no “seems to help” on the start settings. You’ll notice it or there is an issue somewhere else. The 15 is the start amps the ms number is how the long the start 15 amps goes on for in milseconds. With the main/max amps set at say 5 amps you can then play with the start amps and duration until you get it working consistently.

If changing the start amps does nothing then start looking at all the connections. I’ve seen foot pedals mess up to cause starting issues.

Long edit:

After rereading my post I think it comes off a bit harsh which wasn't my intent. There are many things that can effect arc starts in TIG welding. Oxidation of the tungsten tip is the reason most of the times. Whether it comes from welding dirty metal, fan blowing your shielding gas away, bad seal on the tail cap o ring, crap tungsten, partially clogged gas lense, bad seal on cup to torch body connection, preflow setting too short, post flow setting too short along with many other things.

I've noticed that Miller sets their start amps and duration for a perfect world which can cause issues when things aren't perfect. The 15amp/90MS is just a setting that I have came up with that works well for me across a few different dynasty and maxstar welders.

Just because you have to adjust the start amps and duration doesn't mean something is way wrong just that something isn't probably perfect which is just the way it is some times. I look at it like having to program in some taper on a lathe to make the part not have a taper. It could be that the headstock is a touch off or its just the part you are turning is deflecting some under cutting pressure. Easier to program out the taper than mess with the headstock for each part.

 

[eKretz]

I've had this "problem" on all sorts of TIG welding machines. In my experience it's generally down to a bit of contamination or oxidation on the electrode. Keep your postflow set correctly and be cautious of getting the electrode too near to the work, especially with AC. If I get a "no start" condition, generally I bring the tungsten down to the workpiece (arc off, no pedal) and give it a very light drag for a short distance. Then lift back to normal arc distance and hit the go pedal. As gary-sc says, I've never had that not do the trick, regardless of machine.

 

[Jim Moser]

I get the start and duration, don't see any min amps setting though? But I think the foot pedal was the culprit, working fine now. The switch in the pedal just floats in a slot depending on the bottom cover to secure it so a little hot melt glue seems to have fixed it. I don't understand how it could weld at all if the switch isn't activated? But I think I had this problem before and messed with the pedal to solve it. I couldn't hear the switch cliking before I opened it up so must have been the issue.
Thanks for the info
Jim