[BC] 3 phase to single phase conversion

[RichardBJohnson at comcast.net]

Your phase converter is either defective or improperly sized if it has the 
problems you cite. 

Naturally, it is best to have three-phase at the site. However the electric utility 
company will often not run three-phase up the side of a mountain to feed your 
"inconsequential to them" load, unless you spend about $50,000 per mile 
on an existing feed. 

I have used properly-sized phase converters on several mountain-top sites 
including one with a 125 kVA demand. That was a big one made by Roto-Phase. 
They will start fine if they don't have a load on them while starting. 

Plus they are extremely quiet unless just left on their shipping pallet which 
will act like a sound-board. They need to be properly mounted as specified 
by the manufacturer. 

The generated phases will have the same regulation as the single-phase 
input, It has no choice, the phases will be balanced unless the machine 
is improperly sized so it runs at a slip-speed. The single-phase input 
will have an ampacity that is 1.73 times the load currents on the output 
phases. Therefore. the service entrance needs to be sized correctly. 

----- Original Message ----- 
From: "k7cr" <k7cr at blarg.net> 

I have couple comments about these critters. 

1- If at all possible, get the power company to install real 3 phase. 

2- Consider a transmitter that will operate on Single Phase. 

3 -Compare the costs of replacing the transmitter with something with 
switchers that will run on single phase to the cost of the phase 
converter. 

4- NO these things are not silent, at least the type that I am familiar 
with (running a 20-25Kw FM Rig) And they generate a good deal of heat. 
They need a separate room and ventilation. 

5- Beware of inrush on start up....I can be large. Don't even think of 
using your Aux Generator to start one. (Unless you have a BIG genny) 

6- Note that your regulation will be very poor. For example, I had to 
modify the filament regulator in a transmitter to provide for more 
range from Filament on only to both filament and plates on. 

7- Be very careful about which phase you connect to what in your 
transmitter. Before you do this, carefully check with the Tx maker. 
(This is all due to the relatively poor regulation of the generate 
phase)