Welding Tips and Tricks

Hi to all

the subject probably sounds grander than it really is.
The question is how do people stay within the duty cycle of their welder?

I guess it applies to any welding method but TIG is my usual method currently.
A lot of the time it is not an issue but other times you have everything tacked in place and then you can have quite a lot of continuous Arc Time (especially if you have a torch cooler, not that I do at this stage). Some machines will object and overheat and cut out. Particularly the cheaper machines where you are using them at the upper end of their capacity.
Currently I monitor the point at which the fan turns on (and off) which is probably overly generous

So just curious really as to how many people ponder this? I guess I just want to have my machine last as long as possible. The thought of paying for new circuit boards scares me

Regards

Ralph

My machine at home has 100% duty cycle to the end of the dial and the fan is always on. On the other hand, machines with less, when using them full on, the torch's power cable will give out before the machine does, water cooled or not. We run our machines full on, every day. I have been abusing the same synchrowave for 16 years. It's a 250 amp machine with a 250 amp torch. I have probably munched a dozen power cables in that time.

So, more than any real concern for the machine, it's the torch I tend to notice. If it starts to get warmer than normal, I just stop and let a fresh charge of water cycle through it. On heavy stuff, I will run two machines simultaneously, switching torches every 5 minutes or so if I am going to be at it awhile.

first you need to know the duty cycle for your machine

duty cycle , on most machines , is how long you can weld in a 10 minute period

so if you have 50% duty cycle at 150 amps you can run 5 minutes ON 5 minutes OFF

Hi Kevin

yes I know what the duty cycle for my DX200 is. At 200A the duty cycle is around 20% and 60% at around 150A.
No problem there.
What I was curious about was how other people keep track of that 2 minutes in 10 when maxing the machine. Particularly when you are doing lots of little sections of welding. Maybe this is an idea for an App where your phone keeps track of arc time with the on time being sensed by the camera as a light sensor.
Further complicating it is the foot control is used meaning that it is not always running at 100% of the 200A set on the machine,
I would love it if the machine had a 100% duty cycle at 200A but that is not the case.

Regards

Ralph

You said DX200, do you mean a Dynasty 200DX?

You have other things to worry about, like making quality welds. You are going to REALLY have to work to overheat the machine. Like you said, how long are you ever at max amperage. Even then it doesn't just let out the magic smoke and die, it will throw a code, shut it down to cool and restart.

Sent from my SCH-I605 using Tapatalk

Hi Xryan

yes a Dynasty DX200. Very happy with it despite having initial issues with it as discussed in one of my first posts with getting an arc to start.
Here is a bit of recent 'work'. I decided my old van needed some cup holders.






And no, there was no maxing out on this.

Thanks for your reassurances
Ralph

As far as duty-cycle goes, also check the specs on the machine for the environmental conditions they measured this in.

Many machines may list something like 20% duty cycle at 100%, but the small print may show that this is with an ambient temperature of 40C/104F! Especially the 'name' brands will have this info buried somewhere in their docs.

This can then be thought of as the 'worst case' scenario so that duty-cycle is wht you'll be able to reach pretty much always.

Once the ambient is (much) lower then as a result the duty cycle also increases, so you may well hit 50% duty cycle at 100% when the ambient air is 15C/59F.

With inverters the duty cycle limit is basically heat-soak. Cooler air helps the electronics stay cool and run longer.

Of course machines with 100%/100% duty cycles also work around this problem by using 'oversized' rectifier setups that could (in theory) put out much more amps at a lower duty cycle, but they limit them to a certain level where the heat produced never exceeds the cooling capacity in the unit, so you get a 100% duty cycle at any setting.

More costly, but for full time production setups running machines in the top 20% of power most of the time it can be suitable.

If you want to you could do an experiment and open up the machine and attach a thermocouple to the fins of the main cooling blocks on the power units. Close it back up and run it at full power with that and see how hot it needs to be before the machine shuts down. May well be quite a high temperature that you'll never reach in normal use anyway.

I have a pretty basic Oerlikon CITIG 1500AC/DC (which I modded to take a pedal) and even though it's 30% duty cycle at 150A (max) I never managed to hit that with normal use.



I did measure with an external amp-meter that it does hit (and actually exceeds a little) the rated 150A on the cable to the torch. (an interesting test by itself even to see how linear the pedal response is, but not related to this..)

Bye, Arno.

some quick and dirty Duty Cycle testing
https://www.youtube.com/watch?v=ELhpERIprnw

Years ago I was up on staging and the job weld inspector for Chicago Bridge and Iron was below and yelled up at me to give him a 2" stub (we were burning 5/32 7018) so I reached in the stub bucket and threw one at him. Well - that wasn't exactly what he wanted - and he proceeded to let me know in a language common on construction jobs. So I burned a rod and when down to a 2" stub he knew what amperage I was burning at (the machine was a long ways off and leads to maybe 40 different machines were running around like spaghetti in the pot) and he could tell you whether it was in specs for the rod.

rick9345 wrote:some quick and dirty Duty Cycle testing

Oh heck no, not him again. Pretty much everything "Mr. Tig" does is quick and dirty...

Metal_pig2001 wrote:Hi Xryan

yes a Dynasty DX200. Very happy with it despite having initial issues with it as discussed in one of my first posts with getting an arc to start.
Here is a bit of recent 'work'. I decided my old van needed some cup holders.

Ralph, are those real Kiwi sheepskin covers next to the new cupholders? How do you guys drive with the cupholders on the wrong side anyway?

I still don't know how you guys don't fall off the planet being upside down all the time.

Happy ANZAC day. (belated)

The Post Not meant to showcase Mr Tig,but the method to test ones own machine.