I was reading on "the other site" about some chap explaining the pros and cons of different ways to run 3ph tools on a single phase supply.
It was very
long winded thorough, and he totally dismissed Rotary Converters on the grounds of running costs....

Now to my mind there is nothing to worry about as 3 phase motors are quite a bit more efficient than single phase motors. OK you have to add the Rotary costs but together you shouldn't see much of a difference over a single phase motor of the same power output.
This chap was claiming his rotary and machine was costing him about £5.00 an hour to run and as a result he sold his rotary and bought a VFD which he claims is much cheaper to run.
Rubbish, total rubbish. You'll only use what power the motor/s need to run smoothly....At £5.00 an hour I'd sell my machines in an instant....
So I decided to measure my stuff to see what is really going on, like I had nothing better to do but I was now intrigued...
So here's some "measured" facts.....
My Rotary converter, 2.2Kw or 3HP
Mill, 1.5HP 2.5A
Rotary on it's own uses 330W/1.88A
Rotary and mill with the transverse motor also running (2 motors) 720W/5.33A
If you minus the rotary that makes the mill 390W/3.45
At a total of 720W that's around £0.10 an hour.....so 10hrs mill usage will cost me £1.00
Hardly break the bank at that rate would it....
I hope you find that interesting.....
