So should power transformer bodies be grounded?
I think its confusing for a EI core lamination. I have multiple same model # HP power supplies that have the same transformer (6200 series). They all have ground, line and neutral solder points. But some of them have a chassis ground point that is 2x standoffs + internal star washers that touch the transformer plates and screw into the chassis walls. The other one has a extra like serrated jumper + wire that goes from transformer body to the ground solder point terminal on the primary of the transformer, and also the standoff + serrated washer (so you can say its a 3 point ground, 2x standoff to chassis and 1x serrated solder point to ground wire).
But I also think that these things are laminated. I mean what is it doing to ground a single lamination via a serrated washer, be it to the ground wire or the chassis?
How imporant is it that I take the earlier revisions with the slightly smaller transformer and add the serrated solder point so the transformer lamination is connected to the ground wire solder point, and not just the chassis? The bolts are isolated with a special washer, as not to make a shorted turn, so even that serrated solder point is still only possibly contacting a single lamination.
Like with a welded transformer it makes sense I guess, since its all electrically connected. But with the individual compressed laminations it seems just dodgy to ground a single lamination? Do they just assume the varnish job is bad and their not really isolated plates?