Don't know, doesn't seem reasonable, though.
Edit, later. I remember one shop I worked in had a neat little horizontal VN, no one would use it because Walt, the old timer, had had a wreck on it and refused to use it.
I played with it a bit and determined (I don't remember how, this was 40 years ago) that it had been wired backwards. I got the electricians to reverse the wiring and it worked flawlessly. I ran it when ever I needed it because no one else would touch it.