Voltage drop through a transformer

[retire09]

If you run 250' from the service with 277/480 to a transformer and drop to 208, will the voltage drop on the 480 volt run create a voltage drop on the 208 volt side of the transformer?

 

[electrofelon]

If you run 250' from the service with 277/480 to a transformer and drop to 208, will the voltage drop on the 480 volt run create a voltage drop on the 208 volt side of the transformer?

Yes, the transformer will always change the voltage in a fixed ratio. For example, if this transformer was "Seeing" 460V, the secondary would be 199V. The transformer itself will add some voltage drop under load as well just like any other thing that isnt perfect.

 

[GoldDigger]

Some transformers are built with a set of taps rather than single connection points on the primary side to allow you to correct the output voltage when the input voltage is known to be different from the nominal value. But this will not help completely when the voltage drop at the input is caused by a variable load.

 

[ActionDave]

If you run 250' from the service with 277/480 to a transformer and drop to 208, will the voltage drop on the 480 volt run create a voltage drop on the 208 volt side of the transformer?

You will always get some voltage drop on any circuit but 250' is not far at all for 480V, it's not even that far for 240V.

What is the application and load?

 

[kingpb]

If you run 250' from the service with 277/480 to a transformer and drop to 208, will the voltage drop on the 480 volt run create a voltage drop on the 208 volt side of the transformer?

That is pretty much the reason taps are provided on a transformer. I would imagine the -2.5% tap should get you back to where you want to be, i.e. slightly higher than 208V on low side, with transformer loaded.