help please with toroidal transformers selection

[Tom J]

Here is the link from UK supplier I found on this forum (no relation to merchant)
http://www.airlinktransformers.com/c..._transformers/

1. Common design with 50VDC Drivers - lets focus on voltage first

50V - (10%50V)=50V-5V=45V safe voltage

10% is deducted -EMF(slowing down motors, change direction)

Now we need calculate correct voltage of secondary coil of the transformer

24V/1.41=31.92V

From above link we can get 2x15VAC (in series 30V), 2x30AC in parallel or closest or 2x33VAC n parallel too.

I have similar one 420VA 2x30V AC
This gives me 41.5V DC after being rectified on idle
I loose about 3.5-4V, would like to have max 45-46VDC

Now how to choose power? (current figure, as voltage is known)
Power source can have lower current than current of those 3 motors (usually 50-70% of nominal motor current) - why?
Driver takes current from psu while PSW cycle is on, so avarage current consumption by motor is lower than motor current.
Lets say we have 3x3A motors, so no need to have 9A as 6.3A is enough
(3x3A)x70%=6.3A + 10% spare power
6.3Ax1.1=6.93A

so we choose 7A

32Vx7A=224VA
here is exact tranformer:
http://www.airlinktransformers.com/c...Filter+Results

Does somebody used 33VAC or 36VAC?
I would like to know what DC voltage will be after Diode Bridge Rectifier and big capacitors like 2x10.000uF
and same for popular 70VDC drivers please. 70-10%=63VDC
48VDC what ?VDC
50VAC what ?VDC
55VAC what ?VDC- probably more than 63V - guessing here