I know that a 230/400V 3phase motor requires 230V on each coil. No more and no less. So on a 3*230V grid it would be wired in Delta, on a 3*400V it would wired in Y.
We also put this in practice and wired the motors and tested errors etc.
But thinking about it now I noticed that we never grounded the center point of these connections. How can a Y-config at 3*400V produce 230V on the coil?
Is there a mathematical way of calculating this? It's confusing since there's 3 voltages that are all averaged at 400V but measured at any given moment they're 3 very different voltages connected to eachother.
I have however also seen images online of a delta/Y connections that do ground the centerpoint: And here it totally makes sense that the coil get 230V because we know that L-N voltage is sqrt(3) of L-L voltage.
I feel like I'm missing something here.