Replacing a step down dry type transformer

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Hi

I am planning to replace a 75 KVA GE 9T23A3874 dry type transformer with Cutler Hammer 75 KVA V48M28T75EE

I would like to clarify that I'm right about the voltage for both units (480 Delta primary, to 208Y/120 secondary), and to ask if there is anything I have to consider that I may not thinking of other than to just swap the units.

Thank you
 
If the impedence is different it will effect your available fault current (Possible to exceed AIC ratings of equipment) and your arc flash study may need to be updated.
 
Whether or not the primary is delta on both kind of doesn't matter much in most situations, you will still have 480 volts in and 208/120 out. Otherwise as mentioned a different impedance will result in a different available fault current.

75KVA is low enough capacity the available fault current likely isn't just too high and you may actually have to try a little bit to get a situation where a device is subject to more than 10kA.

I did a quick fault current calculation from a spreadsheet application that says for a 2% impedance transformer and 10 feet of 3/0 secondary conductor your available fault current is about 9800 amps. This doesn't even consider limitations of the primary circuit and assumes the primary supply can deliver an infinite amount of current.
 
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