What are the implications if a transformer is underloaded for example

A transformer rated 300kVA but the load it takes is only 220kVA

 

What are the implications if a transformer is underloaded for example

A transformer rated 300kVA but the load it takes is only 220kVA

There are none. A load takes what it takes and the rating is the maximum load that can be supported without consequences.

 

The only consequence is that the transformer output voltage will be a little higher due to less current through the internal primary and secondary winding resistances.

 

Does a little higher mean negligible in this instance. For example if I have 10:1 transformer rated for 5 Amps and I place 120VAC on the primary and draw 1 Amp from the secondary how much does the voltage increase?