Hello everyone this is my first thread.I have been welding with a oxford oil cooled welder for 30 years time for a change . I have got the chance of a Thermal arc fabricator400mig 3 phase & vf4-ec feeder. Are they any good it will be used for general farm use.On the transformer why is there 3 Earth input plugs .there are 2 knobs on the front one has 4 settings a b c d those are the volt settings i presume. The orther knob has 10 settings 1-10 those are for the amps i presume . please correct me where i am wrong.