help with the wirespeed/welding current display - accurate?

[Todd]

Regarding the accuracy of the wirespeed/welding current display (specifically on the Power I-Mig 205P - pulse mig, [but does it vary for different Everlast mig models?]), I've searched on the forum and could only find some conflicting info. Someone said actual wire speed was a little faster than the display indicated, someone else said it was double what was indicated. Could I get some more input/experience, hopefully for this machine?

If the display is grossly inaccurate, why is that? Can the display be calibrated?

Secondly, someone said that amperage output was about "65" less than what the display indicated. Is this correct?

Thanks for the assistance!

[geezer]

I wrote a piece on Dailing in the Imig 205 and came up with the numbers relative to the readout,,,all through experimentation,,,that being said,,,,there is an easier way to dial in your welder regardless of the wire/speed readout...that is by setting the voltage dial at the proper voltage for the material thickness,,,this can be determined by using the many available calculators of charts....then note the position of the dial ,,,,,for example let's say the dial is at 12 O clock,,,,,turn your wire speed to the 12 O Clock position,,,,,with both dial's in that position you are probably close enough to just give the wire speed/amp dial a slight tweak to get it to run nicely....The idea being that the Dials for each are designed to cover a range for the welders out put,,,,the movement of each dial corresponds to the range value of the other...example full open...on wirespeed would require full open on the volts.....not an exact formula but a logical design perameter when building a device like a welder...

Something to get you started and up and running.....Dial readings are not exact because they don't know what the wire size is that you are running and any small variance in the roller size will change the out put of wire...so they are not really accurate for anything except for you to use as a reference for reset as you gain experience..on your particular machine..

[Todd]

Thanks very much for your reply, Geezer. I appreciate your direction. I do, respectfully, differ on the inaccuracy of the display. Millers, et. al. have calculators specing the various optimal settings for different materials, etc. Their ips spec is not rounded to the nearest 50 or 100. It is meant to get a user very, very close to optimal for that particular situation. They've spent a lot of time testing this, so the user doesn't have to spend a lot of time testing as well. Other manufacturers have calibrated their display very closely to actual wire speed. The diameter of wire changes the speed in an extremely negligible way.

With this in mind, it should not be a problem for Everlast to do the same. Having a calibrated display would make it a lot easier to set the machine (especially if a person doesn't weld everyday!) using Miller's handheld calcuators (or the computer versions). Have you ever checked to see if there is a pot adjustment to actually calibrate the display, after measuring ips? Thanks again!

I wrote a piece on Dailing in the Imig 205 and came up with the numbers relative to the readout,,,all through experimentation,,,that being said,,,,there is an easier way to dial in your welder regardless of the wire/speed readout...that is by setting the voltage dial at the proper voltage for the material thickness,,,this can be determined by using the many available calculators of charts....then note the position of the dial ,,,,,for example let's say the dial is at 12 O clock,,,,,turn your wire speed to the 12 O Clock position,,,,,with both dial's in that position you are probably close enough to just give the wire speed/amp dial a slight tweak to get it to run nicely....The idea being that the Dials for each are designed to cover a range for the welders out put,,,,the movement of each dial corresponds to the range value of the other...example full open...on wirespeed would require full open on the volts.....not an exact formula but a logical design perameter when building a device like a welder...

Something to get you started and up and running.....Dial readings are not exact because they don't know what the wire size is that you are running and any small variance in the roller size will change the out put of wire...so they are not really accurate for anything except for you to use as a reference for reset as you gain experience..on your particular machine..

[Rambozo]

I would check your actual unit before doing anything. There have been a constant stream of improvements to these machines, so it may be that the display is now correct. It is an analog control so there may be some minor unit to unit variation, and it might not be perfectly linear, either. Miller has that as well. I guess someday there might be a digital encoder mounted on the drive roller to read exact speed for a servo system, or run the drive via a stepper motor gearbox. I bet all the fully automatic CNC robotic welders have something like that. For manual machines most have just had manual controls with a printed dial for years and years. It works and virtually all welding calculators tell you that some fine tuning may be required to achieve optimal settings. The operator's technique has quite a bit to do with it also.

[performance]

The display is much more accurate than the past, especially with the MTS series from what I can tell. Geezer is right, wire diameter plays a part in the error. As the unit wears in, some difference in actual speed may be noticed as well. IF though, the amperage is reading, in active welding mode, it should be fairly accurate...no way it's 65 amps. Not sure where that was reported. I've seen some reports of problems with other peoples units with huge amp errors, but anytime anything like that has been reported with ours, it usually was with the measurement technique or something else was out of whack. You might occasionally observe a small amp discrepancy in the mid range from actual to what is set, but it should always be less than 5% or so...and usually within an amp or two...or even less.