3 phase transformer

[keithmech]

I have a 3 phase transformer that I want to us on a machine.
I need to get less than 100 vac out.My input voltage is 240.
The transformer plate says 220 pri. delta , 110 sec. 380 wye
110 sec..There are 6 connections on one side and 3 on other.
The 6 connections now when use as the input give me 120vac out.
Could I connect single phse to each section of the transformer,
use 120 and get about 60 volts per out or connect it wye and use 3 phse?
Or just get 3 new transformers.My goal is to end up with less than 140 volts dc for my servo motors.

[Al_The_Man]

I am a bit confused as to what the star (wye) voltage you are getting right now between phases?
If you are currently getting 120v between phases, then if you require <140 then use any two phases, if you use the star point as a common for the phases then the output will give you above half of between phases close to .6x.
Al

[keithmech]

The 120 volts is ac.I need less than 100 volts ac so once thru the bridge
rectifier 100 x 1.4 would be 140 volts dc.I think the 380 is for european
voltages.140 volts dc is max.,60 to 100 vdc would work, that is why I was
also wondering about the 120 volts ac 1 phase into each coil of the 3 phse transformer.With a 2-1 ratio would be 60 volts ac or 84 volts dc.

[Al_The_Man]

I think I get it, you have a 3 ph trans. and want to use it on 1 ph, If the KVA is large enough, you probabally could use one of the delta section input and use the secondary of that section and what would be the star point, I assume you only need one AC source?
Al.

[keithmech]

I was hoping to run each servo off of a section of the 3 phse.
transformer, have 3 rectifies/capacitors.Can a 3 phse transformer
if the kv rating is high enough,be used as 3 single 1 phse transformers.

[Al_The_Man]

I haven't tried this but I think it may be possible, you will have to be carefull about phasing the inputs, as the windings share the same magnetic core, and be able to separate all the primary terminations for each pri winding.
Al.