The output voltage will be the difference of the two 3 phase legs which are 120 degrees offset from each other. The 120 degree offset is what you are failing to take into account.
If the two output legs were 180 degrees offset from one another the difference (the output voltage) would be the SUM of the two legs. The output legs are not 180 degrees from each other, they are only 120 degrees offset from each other.
Mike,If we are in a universe where the laws of physics are not relevant then you are CORRECT!
Mike,
Take a look at this and you'll have a better idea of how VFD's work. If you look at the image, all the input is turned into DC first. Then back to AC at whatever voltage the VFD specs. The conversion is much more sophisticated than a simple single phase/three phase.
The DC voltage from a single phase rectifier will be DC voltage = AC voltage divided by the square root of 2. Always! Rectifiers do not boost the output DC to any voltage you want. It is always AC voltage/1.4 for single phase AC.
240v AC -> rectifier = 157v DC out.
Yep, on this detail I am wrong and you are right. I will admit when I am wrong.Sorry, it is always AC voltage*1.414 for single phase AC = 311VDC output for 220V AC input.
I gave a link to a single phase 120 in / 240 volt 3 phase VFD several posts back. I guess you ignored that. Hard to explain when you’re ignoring meIf what you said were true I would be able to buy a cheap 240v VFD and run a 480v 3 phase motor with it.
I gave a link to a single phase 120 in / 240 volt 3 phase VFD several posts back. I guess you ignored that. Hard to explain when you’re ignoring me
MikeI know how a VFD works! You are ignoring the 120 degree offset between any 2 output legs of a vfd which you can not do!