Can someone explain how the CP302 Miller MIG Power source controls Amperage?

[Ehanson]

Like probably most MIG Power sources, I am wondering how the user chooses the welding amperage?
I see a single control on the CP302 Miller for voltage control, I have a Miller Xtreme 12VS wire feeder,
which has a control for wire speed, but I don't
understand how you choose the amperage? ( if you were running the CP302)
Is amperage requirement done automatically through the voltage setting?

 

[firemanmike69]

Wire welding if a constant voltage process, the amperage is dependent on voltage and wire feed speed

 

[Ehanson]

Wire welding if a constant voltage process, the amperage is dependent on voltage and wire feed speed

Yes, OK , I figured it must be something in the unit, (a circuit board, processor?) that can ramp up or down the amperage.
Kind of baffles me how, with different wire sizes, but must be able to do it somehow.
I know the Miller Xtreme 12VS has a switch for CV (constant voltage) & CA (constant amperage).
I thought MIGs would have three settings, voltage, amperage & wire speed.

 

[Shield Arc]

The hardest part about Mig welding is getting the welder set correctly!
This calculator may help you.
MIG Solid-Core Welding Calculator - MillerWelds

 

[Ehanson]

The hardest part about Mig welding is getting the welder set correctly!
This calculator may help you.
MIG Solid-Core Welding Calculator - MillerWelds

That is a very helpful chart from Miller, but still does not answer my question of choosing voltage and amperage using the CP302 Power Source?
Any ideas, or anyone familiar with this unit?

 

[Big Barn]

I'm NOT familiar with either unit.

Use the weld calculator from Miller. Set voltage on the power source. The wire speed (IPM) setting on your suitcase feeder will set your. amperage.......I think

 

[Shield Arc]

When running a CV Mig welder the wire speed controls the amperage. And there is a knob for the voltage.

 

[Ehanson]

Ok, I think I get it, thankyou everyone!