Interpret a graphic

[performance]

Inverters pass through the "0" point much more rapidly than transformers. Square waves are either on or off with little drop basically between + and - voltage. This transition happens so quickly that the arc really isn't perceived as going out. Sine waves have "flat" spot on the ends of the wave that transitions directly to the opposite equivalent voltage.

[DaveO]

Thanks for responses. I sure wasn't expecting a "less technical manner" of explanation mixed in with the technical explanation: I can't tell you how long I've stared at that thing, trying to figure out how the lower half of that sine wave was moving from 360* to 180*.

[Rivets]

Thanks for responses. I sure wasn't expecting a "less technical manner" of explanation mixed in with the technical explanation: I can't tell you how long I've stared at that thing, trying to figure out how the lower half of that sine wave was moving from 360* to 180*.

Hi DaveO,

Just pretend that the x-axis is one of the wires to the torch.

Current goes right during the + half of the cycle then left during the - half. Just a visual thing.

rivets

[DaveO]

Thanks- I finally get that those arrows are an add-on to assist understanding. The graphic could have been expanded just a little, maybe to show a torch with a + sign and a torch with a - sign.

Miller pulled this TIG manual from their website. I read somewhere that it had been replaced with a paid download version, but I don't see it on their site.

[Rambozo]

Inverters pass through the "0" point much more rapidly than transformers. Square waves are either on or off with little drop basically between + and - voltage. This transition happens so quickly that the arc really isn't perceived as going out. Sine waves have "flat" spot on the ends of the wave that transitions directly to the opposite equivalent voltage.

Thanks, I figured the inverters didn't put out a pure sinewave, and just squared up the transitions a bit, to avoid that issue, but I haven't put one on a scope to check.