Transformer 3ph 220-140 changeover to 380-140 Volts

Peter from Holland · Nov 26, 2020

I have a transformer in my 220volts 3ph Mikron WF2/3SA
It is a 220 volt to 140 volt transformer
Primary is in star (with a neutral)
Secondary is in delta
I figured out that with the secondary in star and 380 volts on the primary the output should be 140 volts again
But if I connect the transformer like that it blows the fuses
What am I doing/thinking wrong ???

Peter

adh2000 · Nov 26, 2020

The neutral is tapped off the primary coils. You cannot connect that neutral to a load on the secondary. Primary and secondary must each have their own neutral tap for your plan to work.

Sent from my iPhone using Tapatalk

Peter from Holland · Nov 26, 2020

The neutral is not connected to anything Neighter of them

Just changed the secondary winding from delta to star
And then I connected the primary to my 380 volt 3ph powernet

Peter

adh2000 · Nov 26, 2020

Neutral should have a connection to all three coils. This is star:

star connection diagram - Google Search

Sent from my iPhone using Tapatalk

BT Fabrication · Nov 26, 2020

sounds like you need a different transformer......

SomeoneSomewhere · Nov 27, 2020

Even though the ratio is right, you still can't put 380V per winding into a transformer built for 220V per winding. There won't be enough inductance to limit the current correctly.

Real-world transformers aren't as ideal as you would hope.

Search

Largest Manufacturing Technology Community on the Web

Search

Transformer 3ph 220-140 changeover to 380-140 Volts

Peter from Holland

Diamond

adh2000

Titanium

Peter from Holland

Diamond

adh2000

Titanium

BT Fabrication

Titanium

SomeoneSomewhere

Hot Rolled

Similar threads