120/208 3 phase service

[esc1234]

This may be a question with an easy answer, but it is new to me and I need help. I am trying to establish a 120/208, 3 phase service for a shop that requires that power but the utility that is present is 120/240, 3 phase delta. How do I get the desired results? Thanks

 

[roger]

Delta to Wye transformer sized accordingly.

Roger

 

[augie47]

If you only need the 3 phase 208 (and not the 208Y/120), you can accomplish that with a buck/boost transformer for less $$$.

 

[esc1234]

Is there a schematic or diagram somewhere that I can see on this type of transformer?

 

[iwire]

Here is an example but replace the 480 delta primary with a 240 delta primary.

 

[roger]

The link below will show some more Wye drawings from Scott Thompson.

http://www.electrical-contractor.ne...453/New_3_Phase_4_Wire_Wye_Transfo#Post177453


Roger

 

[Rick Christopherson]

I am trying to establish a 120/208, 3 phase service for a shop that requires that power but the utility that is present is 120/240, 3 phase delta.

I would first double check with the customer that this is truly what they want/need.

You didn't say what kind of shop, but to me, this generally implies a facility with small to medium 3-phase motors, which are typically rated for either 208 or 240, as opposed to motors that are rated exclusively for 208. But likewise, these shops typically also contain many single-phase 240 volt motors, and these are not real happy when they are only given 208 volts.

The 120/240, 3-phase system is generally the best alternative for small/medium shops, at it will satisfactorily power all of the 3-phase and single-phase loads.

 

[LarryFine]

I am trying to establish a 120/208, 3 phase service for a shop that requires that power but the utility that is present is 120/240, 3 phase delta.

I've got to ask: How did a shop get built that requires a voltage other than what is available?

Most modern motors will work on either 208v or 240v. Check each load's nameplate to be sure.