[BC] Multiple Phase Power

[PeterH5322@aol.com]

>Peter I stand corrected... I believe the correct term might be 12 pulse not 
>12 phase.  However as I recall the advertising all stated 12 phase.

Just as 120/240 single-phase is often incorrectly called "two-phase", 
three-phase three-pulse, three-phase six-pulse and three-phase 
twelve-pulse are often incorrectly called "three-phase", "six-phase" and 
"twelve-phase".

"Six-phase" and "twelve-phase" are informal names for particular 
implementations of three-phase power systems.

I suppose one motivation of the advertising copy would be to appeal to 
the notion that if three of something was good, then six or twelve of 
something would certainly be better.

All, however, are three-phase.


In my experience is has not been necessary to operate high-power AM 
transmitters from single-phase.

However, numerous FM and TV transmitters are operated from single-phase, 
where the site is otherwise a good one, but there is no three-phase 
utility power within an economic distance of that site.

Three-phase power may be manufactured from single-phase, using a rotary 
converter sized about 2 HP per KVA of three-phase load. Every 
installation is unique, of course, and some "balancing" will be necessary 
to obtain the best possible results.

It is conceivable that such an installation might have single-phase as 
the primary (utility) power source converted to three-phase, while the 
secondary (backup) power source could be a three-phase genset.

Remote starting is often an issue with large converters.