MIG settings confusion

[FirebirdNick]

Hi
I’m new here, so please excuse me if this question is really ignorant, but I inherited a MIG welder which I use for garden art. I’ve mostly figured it out by trial and error, and it works ok, but now I’m wanting to do some more precise work and I clearly don’t really understand its settings. It has dial/controls for “MIG: VOLTAGE, MMA: CURRENT”, “MIG WIRE SPEED” and “INDUCTANCE”. BUT…When I adjust the voltage dial, the lower voltage display marked with the letter “V” underneath doesn’t change from “0.00”. Instead, the ampage display changes (range: 23-283) (see pic 1). I therefore assume it’s quoting me amps, partly because of the “A” written under the upper display and also because it’s a 280 amp welder? But why? The dial says MIG voltage and I thought the convention was to manually adjust voltage, with amps then being calculated by the machine based on a combination of voltage, wire speed and any resistance in the circuit. If I flick the switch from MIG to MMA, the lower voltage display “V”, then lights up and sits around +/- “60”, and I can still adjust the upper display “A” with the voltage dial. I find this really confusing and I hope someone can help me understand it with a simple, basic reply please. Thank you‍

 

[Cobbler]

Welcome to the forum Nick. Can’t help you on the settings, but someone knowledgeable will be along in a bit.

 

[Kalts]

First find out which knob adjusts wire feeding speed. Then turn corresponding knob to minimal setting, pull the trigger for 10s and measure wire length. Repeat for maximum and middle settings. In that way you will have very rough idea of feeding properties. Next find out the voltage knob, turning it between min/max while welding should have much more impact than inductance knob. The numbers displayed are dimensionless and only relevant for that particular chinese unit at hand. Do not put much faith into those numbers and do not try to adjust welder by using some recommended values.

 

[AVI_8]

When you’re welding mig does the voltage maybe display whilst you’re welding then drop down to zero when you stop?

 

[hotponyshoes]

I wonder if its showing you 28.3v when in mig mode?
Only because I can't believe that machine can do 280amps unless it's a 3-phase set?

 

[eddie49]

A photo of the data plate ( perhaps printed on the back of the case ) would be helpful. However, whatever is written there is likely to be just as much make-believe as the numbers displayed on the front panel. There is no way that a box this size can do 280 Amps, maybe 200 at best.
The digital displays often are only valid during the welding operation, not when setting up.
It is not unusual for labelling of controls and displays to be completely erroneous. The "A" display could even be showing wire speed in inches per minute...
In MMA mode, an open-circuit voltage of 60.4 volts is quite common, so that value may be correct.

 

[tom2207]

if in doubt put everything to half way , and get a bit of decent plate ,,, and give it a go ,
adjust from there ,,, or post a pic or two and folk here will guide you ..
watch a few how to mig videos , and it will all drop into place ...
and of course , welcome to the forum.

 

[FirebirdNick]

Thanks for all the replies and for confirming a few suspicions. Thanks for the warm welcome too I’ve answered your comments below…

First find out which knob adjusts wire feeding speed. Then turn corresponding knob to minimal setting, pull the trigger for 10s and measure wire length. Repeat for maximum and middle settings……inductance knob

I tested the wire speed: Wire speed: minimum = 7inches/10sec , 1/2 way in dial = 11inches/10sec , maximum = 12 inches / I haven't noticed the inductance knob making any difference to the weld at all. I figured it must be subtle, or useless.

When you’re welding mig does the voltage maybe display whilst you’re welding then drop down to zero when you stop?

Not sure, I’m too busy making sure I don’t set fire to myself. . I’ll have to check this.

I wonder if its showing you 28.3v when in mig mode?
Only because I can't believe that machine can do 280amps unless it's a 3-phase set?

There is no way that a box this size can do 280 Amps, maybe 200 at best.

It’s single phase with a 15 amp plug. It can weld 3/4 inch iron, but I wouldn’t vouch for the strength of the welds, because it’s just my garden art and I’m anything but a pro. But I have tested the strength of some of the 3/4 inch welds. some I can separate with a heavy hammer, some not.

A photo of the data plate ( perhaps printed on the back of the case ) would be helpful. However, whatever is written there is likely to be just as much make-believe as the numbers displayed on the front panel. There is no way that a box this size can do 280 Amps, maybe 200 at best.

I attached a pic of the data plate below.

if in doubt put everything to half way , and get a bit of decent plate ,,, and give it a go ,

I will do this, and I do tend to overthink things, but based on the feedback, and that I like to understand why/how things work, I’m also thinking maybe I should get a decent welder. Because I think this is just going to frustrate me thanks again for the feedback.

 

[henry Kadzielski]

My two cents worth. have you looked up for a manual on that machine, as there seems to be no brand name / model on it. As @tom2207 has stated would be a good start. If you have welded before and are reasonably proficient with a mig it will show you which way to go

 

[FirebirdNick]

The brand name is Rossmark. the manual is useless. It’s generic, not specifically for that model, and the brand has no presence on the internet that I can find.

 

[Jack Ryan]

I am reminded of the loaves and the fishes on the mountainside.

The machine requires a 10A circuit (I1eff = 10.6A) and yet it has a 60% duty cycle at 280A.

Jack

 

[Munkul]

I am reminded of the loaves and the fishes on the mountainside.

The machine requires a 10A circuit (I1eff = 10.6A) and yet it has a 60% duty cycle at 280A.

Jack

Just to make it absolutely transparent for the OP:
That welder either has magical abilities, or the manufacturer is lying

MIG welders are supposed to be constant voltage which you set, and the wirespeed more or less sets the amps.
Since its an inverter it has a constant current mode which is used for Stick/TIG, but some very cheap manufacturers use the constant current mode for MIG as well, as its cheaper/easier to manufacture. Then they just lie/omit details and let the user figure it out.
It will still weld, but not as easy or nicely as a true constant voltage source.

 

[tom2207]

Just to make it absolutely transparent for the OP:
That welder either has magical abilities, or the manufacturer is lying

MIG welders are supposed to be constant voltage which you set, and the wirespeed more or less sets the amps.
Since its an inverter it has a constant current mode which is used for Stick/TIG, but some very cheap manufacturers use the constant current mode for MIG as well, as its cheaper/easier to manufacture. Then they just lie/omit details and let the user figure it out.
It will still weld, but not as easy or nicely as a true constant voltage source.

all true ,,,, but the price paid reflects that too ,,,

Look at all the super power car audio amps that muppets buy ,,, thousands of watts and all from 12v with a 30 amp fuse ,,,,

ye canna change the laws of physics ,,, captain .

but like the amps , they will do enough to keep folk happy ,,,

so lets get welding a bit and post a few pics , watch a few videos , and by tomorrow it will all be a cruise ,, ish

 

[hotponyshoes]

It doesn't sound right to me.
About the best I know of is a 220a mig from a 16a single-phase supply.

That's a branded machine so I would trust the quoted 220a figure.
It's possible they have down-rated it to increase the lifespan but its also a £3k machine and if they could sell a 280a version for £5k I'm sure they would!

Having said that, those numbers on the display must be relevant to something so if you find you need to set it to 205 for 3mm steel and 264 for 4mm steel you can just make notes of what they actually do.
Most of the time I just turn my welder up or down rather than take any notice of what the display says.
A display that read from A to Z would be just as useful really.
No real need to know what the actual power output is for hobby use.

 

[FirebirdNick]

Just to make it absolutely transparent for the OP:
That welder either has magical abilities, or the manufacturer is lying

MIG welders are supposed to be constant voltage which you set, and the wirespeed more or less sets the amps.
Since its an inverter it has a constant current mode which is used for Stick/TIG, but some very cheap manufacturers use the constant current mode for MIG as well, as its cheaper/easier to manufacture. Then they just lie/omit details and let the user figure it out.
It will still weld, but not as easy or nicely as a true constant voltage source.

Yep, I figured from Jack’s comment that it‘s ability was overstated, but I don’t know much about duty cycle yet. Thanks for the rest of this information too. I’m learning a lot here, and grateful for all the feedback/advice. Overall it sounds like the welder is a cheap, overstated, with semi-meaningless data, but for hobby use, as long as it works….plug n’ play.

Think I might get rid of it anyway. The main reason is not the welder. It’s probably just me; I like to understand what I’m doing, and that means having a device that gives correct informatio. C’est la vie

 

[henry Kadzielski]

I like to understand what I’m doing, and that means having a device that gives correct informatio.

Plug n play that is the way to learn. I had one customer (I'll keep the story short') need to get something welded, I said I will get my welder out. He said we have one here, I asked what is it and he told me it was a invertor Unimig. I asked what is it like, he said not so good. I asked him can he show me what it welds like and he showed me a sample. It looked like crap, but I asked have the setting when that weld was done been changed on the machine, he replied no. Well a tweek here and a tweek there and it layed down a perfect weld. I their eyes I was a 'GOD". I have come to realise that a good welder will get a good result with a crappy machine, but a poor welder will not get a good result with a top shelf machine. Knowing what knob to rotate and in what direction is the secret. I was just lucky in this one case I just tweeked the knobs perfectly and got that perfect result in one step. I aslo have had Unimig machines and they have been quite fine.
I am now just used to top shelf machines that once you set your parameters (using the synergic settings) all I do is change the thickness setting for changes in material thickness, position, fitup and speed that I like to weld at. I don't even now know what voltage, wire speed or current the machine runs at and don't really need to know. All that I am interested in is, is it doing what I want the way I want it and if it is yes, move on the the next job.