Transformer and Delta To Delta fed with wye

[dm9289]

At the factory I work at we have a 480Y feed from utility. We run many 1980/1990s DC drives and I believe these transformers may be for isolation. Original Engineers are no longer with us.

Questions does a delta/delta transformer have a problem being fed from a wye?

If it is ok to feed delta/delta with a wye would the output of transformer act as a delta?
I assume yes?

There is a small dash symbol by H1 and X1 what does that indicate?

Thank you for your help and patience

 

[ggunn]

At the factory I work at we have a 480Y feed from utility. We run many 1980/1990s DC drives and I believe these transformers may be for isolation. Original Engineers are no longer with us.

Questions does a delta/delta transformer have a problem being fed from a wye?

If it is ok to feed delta/delta with a wye would the output of transformer act as a delta?
I assume yes?

There is a small dash symbol by H1 and X1 what does that indicate?

Thank you for your help and patience

Yes, you can feed the delta primary of a step down transformer with the three current carrying conductors from a wye service. The secondary of the step down can either be delta or wye depending on the transformer; in your case (delta -delta) the secondary would be ungrounded delta.

 

[infinity]

The Delta primary is just the way that the transformer is internally wired. You can fed it with 480 volts and three conductors from either a Delta or a Wye system.

 

[zbang]

There is a small dash symbol by H1 and X1 what does that indicate?

Even zoomed in a lot, I don't see that dash, where is it?

 

[wwhitney]

Even zoomed in a lot, I don't see that dash, where is it?

The dashed line in the interior angle at the lower left of each triangle.

Cheers, Wayne

 

[dm9289]

Yes, you can feed the delta primary of a step down transformer with the three current carrying conductors from a wye service. The secondary of the step down can either be delta or wye depending on the transformer; in your case (delta -delta) the secondary would be ungrounded delta.

Thank you trying to figure out why some choices were made

 

[dm9289]

The Delta primary is just the way that the transformer is internally wired. You can fed it with 480 volts and three conductors from either a Delta or a Wye system.

Thank you

 

[dm9289]

Even zoomed in a lot, I don't see that dash, where is it?

 

[dm9289]

The dashed line in the interior angle at the lower left of each triangle.

Cheers, Wayne

 

[dm9289]

Yes, you can feed the delta primary of a step down transformer with the three current carrying conductors from a wye service. The secondary of the step down can either be delta or wye depending on the transformer; in your case (delta -delta) the secondary would be ungrounded delta.

Ours is just 480 to 480 no step down so that’s why I assumed it was for isolation or changing to ungrounded delta to reduce trips

 

[dm9289]

Even zoomed in a lot, I don't see that dash, where is it?

 

[Hv&Lv]

The dash represents the relationship between the windings.
Angular displacement between the windings.
Those show no displacement between the windings

Aka Dd0

 

[dm9289]

The dash represents the relationship between the windings.
Angular displacement between the windings.

Would that be similar to phasing dots or am I way off

 

[Hv&Lv]

Would that be similar to phasing dots or am I way off

Thats dot convention. It indicates the polarity of the windings. One lead in each winding is marked with a dot. When current flows into the dot in the primary, the induced currents flow out of the dots in the secondaries.

 

[jim dungar]

The dash represents the relationship between the windings.
Angular displacement between the windings.
Those show no displacement between the windings

Aka Dd0

Correct.
Confusion comes with Wye windings, where the dashed line comes from the common point. Most people never see a de!ta-delta so they think the dashed lines represent the ground connection point.

 

[zbang]

The dashed line in the interior angle at the lower left of each triangle.

Ah, I was looking on the windings, I thought the phase angle thing was obvious.

 

[ggunn]

Ours is just 480 to 480 no step down so that’s why I assumed it was for isolation or changing to ungrounded delta to reduce trips

It's a step down transformer with a 1:1 ratio.

 

[LarryFine]

It's a step down transformer with a 1:1 ratio.

Or is it a step-up with 1:1?

 

[zbang]

Step aside, please .

 

[winnie]

Step aside, please .

Careful, that terminology might stick.