How can i build single pahse 227 from 380 volte 3 pahse delta?

[farhadkhaefi]

hi all
In our factory all load supply from star/delta transformer 3 phase 380 volte,(without neutral system)
we want to install new 227 volte single phase for lighting..
do we can uase 2 phase-phase ?
if we want to build 48 volt dc , it is possible to use this voltage?
tank you every one
f-kh

 

[alehman]

You would need to add a transformer to create a neutral for the lighting, or depending on the situation you may be able to connect you light phase-to-phase at 380 volts.

For 48 VDC you will need to install rectifiers. Most 3-phase rectifiers do not need a neutral.

 

[mc5w]

However, U.S. National Electrical Code requires that lighting be supplied from a solidly grounded system. Since your lighting needs are small, what you want to buy is a 380 volt delta primary 277Y480 volt secondary transformer. Something similar is used in plants where main power is 480 volts ungrounded or resistor grounded.

For a rectifier installation I would highly recommend using a drive isolation transformer if that is not already built into your rectifier set.

 

[far243]

tank u guyes

 

[alehman]

Mike: Good catch. I seem to recall seeing that some place but I can't find it now. Do you have the NEC paragraph handy?