Hi Joe
On (01 Jan 98) Joe E. Dodson wrote to Alec Cameron...
 JE> Has everyone forgotten about power factor? Only in a DC circuit does 
P=IE.
 JE> In AC circuits P=IE(PF).
Not forgotten. Three phase value P= 1.7321 E I (PF) which is almost correct,
provided the supply v and the load Z is symmetrical. As it never really is!
One of the disturbing factors being the ever changing level of solar induced
DC in the overhead earth wires. This adds in the three phase overhead lines,
as a threefold neutral current passing down the transformer wye windings to
ground, but being DC it tends to saturate the iron cores of transformers and
cannot be transformed thru to secondary windings.
In the worst case scenario, sun spots [solar radiation] and the aurora are
noted for the pretty sky display, cursed for the interference with
communications but largely misunderstood for how these disturb grid systems.
Retirement! What a blessed relief.......
Cheers.......ALEC
... *******Youth is such a wonderful thing, but wasted on children
--- PPoint 1.92
---------------