Tom D said:

I am also questioning the wiring from that snapshot.

I am too - the secondary wiring looks distinctly odd for a site transformer - usually they're wired CTE (i.e. 55-0-55 with the centre tap earthed, in effect a RLV TN-S system) - this one looks to be wired as a 110V LV IT system.

   - Andy.

Correct. Should have been wired that way.

Indeed - unless there is a good reason, then 'normal' site practice is a single split phase and earthed in the centre.

Then its not strictly  L1 and N1 secondary, as both are equally live - think more like L1 and L2.

Also one might expect some sort of breakers on the load side if one transformer is feeding many sockets as there is scope for over loading one socket.
16A at the primary side would equate to  about 30 something amp on the 110 side of things so if the secondady sockets are 16A ones, then that too needs a  bit of thought.

Mike

edited for grammar/clarity.

mapj1 said:

Then its not strictly  L1 and N1 secondary, as both are equally live - more L1 and L2.

Yes, this secondary arrangement is properly called mid-point earthing, and definitely L1 and L2. The 'midpoint' or 'neutral' is not distributed as a live conductor (but it could be - they do this in houses in USA, where they provide 220 V single-phase, mid-point earthed, to a dwelling, and lighting and small power uses the 110 V from L1 to N and L2 to N, whereas larger appliances such as laundry appliances, use the 220 V L1 to L2 single-phase supply, with 'ground' connected to N at the transformer.

mapj1 said:

Then its not strictly  L1 and N1 secondary, as both are equally live - more L1 and L2.

Yes, this secondary arrangement is properly called mid-point earthing, and definitely L1 and L2. The 'midpoint' or 'neutral' is not distributed as a live conductor (but it could be - they do this in houses in USA, where they provide 220 V single-phase, mid-point earthed, to a dwelling, and lighting and small power uses the 110 V from L1 to N and L2 to N, whereas larger appliances such as laundry appliances, use the 220 V L1 to L2 single-phase supply, with 'ground' connected to N at the transformer.