Power Pedestal Connections

The two readings must not be identical.

Having been trained in electricity and electronic by the US Navy (6 months specialist school) and also done a lot of household electrical wiring most of my life - wired entire houses - I do not understand why you say the two reading must NOT be identical?? Ground and neutral are the same electrical point in a main panel which means the reading would and should always be the exact same. Can you explain why you say they must NOT be the same? I have never in my life heard of this. Do you mean if it is "bootstrap" they would not be the same?

We do carry a 4 foot grounding rod to pound into the ground if we find no ground at a pedestal. But this is a pain and can be difficult to do so I will wander the RV park checking pedestals to find one that has good ground. If one pedestal has good ground then it is possible the wires exist in other pedestals but are not attached correctly. I then open the box to look inside to see what has been done and whether it is possible to correct the problem - not for someone who does not KNOW how to mess around with electricity. In many cases we find that pedestals have been wired by people who do not know the rules and I can go in to correct the wiring. In some cases entire RV parks in Mexico are incorrectly wired.

As brought up in comments above - if an RV park connects neutral and ground in a pedestal they should also be pounding a ground rod at the pedestal to provide the required ground. As stated in the code book I posted the only place ground and neutral should be wired together is at the main panel. Wiring at the pedestal or "bootstrap" can feed live voltage to the neutral in certain situations. The only way this can technically work is if there is also a ground rod at the pedestal as well as at the main panel.