Three phase and IBM

[Tony Duell]

> 
> > I am not sure about equipment of that date, much less IBM equipment of th=
> at
> > date, but I'd guess that undervoltage is less likely to be harmful than
> > overvoltage. =A0(Some switch mode power supplies may draw too much curren=
> t if
> > the voltage is low, and kill themselves that way.) =A0So err on the side =
> of
> > lower voltage.
> 
> Basically, just about any configuration of wires that are sticking out
> of the wall can be hooked up to these controllers, and if they do not
> like what they are getting, they will not power up ("power check" in
> IBM talk). Just about everything is checked before any of the brains
> get any power.


I suspect if you conencted one of the phase wires to the protective 
ground terminal the results coule be unpleasant....

> 
> Not that one should be careless here, but IBM mainframe equipment does
> offer a bit of comfort when it comes to the smoke test.

Sure, but as you imply, you shouldn't rely on safety devices to get you 
out of trouble. In other words, I';d want to make darn sure I'd got thw 
wires on the rgith termianls before I applied power, rather tan assuming 
it will power-check if I get them wrong. 

-tony