I am curious is how what tests you can perform on this padmount transformer, since H0-X0 is linked.
Testing of transformer is limited if Pri and Sec winding are interconnected. Usually, the manufacturer of the transformer installed a manhole on the top cover wherein you could access the connection of the link (removable)- 2 to 3 inches below the oil level. Some uses ground strap on Xo bushing for isolation of Sec to Pri Winding -internally grounded.
Recently had this issue and contacted Doble for Power Factor and this is there response:
Basically use 2-winding template with note describing the winding having common neutral and only one test line #1 in Overall test plan can be performed with reduced test voltage to 0.5kV.
You can perform Winding Resistance, Demag, Transformer Turns Ratio, Excitation Current, but for Power Factor the only test you can perform with a bonded HO XO is a GST-gR (grounded specimen test guarding out the red measuring lead). If you want to run a full Power Factor you will need to unlink the H0/X0 coupling.