need help ASAP.

Borrow someone else's cord and see what happens. If it does not cause a problem demand the park replace your cord.

If you are no longer around that park pull the head apart and make sure it's wired correctly.

A GFI check for ground faults. Maybe ground isn't connected properly or the ground wire is burnt off somewhere (either in your rv or in the pedestal)

You didn’t even begin to provide enough info or description to even begin to solve your problem for you over the internet.

Disconnect the shore power cord from both ends.

Set your digital voltmeter to OHMS.

Check should show infinity between any combination of the leads (easy to check on the male end).

The park is responsible report it to the office and have them send out someone to fix it.

First thought is a bad cord and you've got excellent advice above. Consider trying another site, see below.

50A is 12,000 watts which is a lot of power and cutting the cord likely caused a short resulting in high transient voltages and currents until the pedestal CB tripped. This can cause damage to the CG power or to your RV and now your GFI trips.

You should give serious consideration to having your RV checked by a good "electrician" because repair can be expensive and for peace of mind.

From your description the CG is a parts replacer and that diagnostic approach can be time consuming and expensive.

BTW For many reasons and especially for 50A power I installed a PI HW50C EMS 19 years ago now in it's second RV. One month later I had 160V at night with a 30A plug. The EMS disconnected and I pulled the plug as I knew the problem was a open neutral.

So as a open question how do you get 160V with a open neutral on a 30A plug?

CA Traveler wrote:
BTW For many reasons and especially for 50A power I installed a PI HW50C EMS 19 years ago now in it's second RV. One month later I had 160V at night with a 30A plug. The EMS disconnected and I pulled the plug as I knew the problem was a open neutral.

So as a open question how do you get 160V with a open neutral on a 30A plug?

Your usage may have been on the 30 amp outlet (one hot).

But, very likely the neutral "upstream" of your site was wired with both L1 and L2. And, an open neutral upstream of you can cause this even if you are just using one hot.

joebedford wrote:
A GFI check for ground faults. Maybe ground isn't connected properly or the ground wire is burnt off somewhere (either in your rv or in the pedestal)

Actually, the term "ground fault interupter" is really a misnomer.

First, a GFI does NOT repeat NOT require ANY ground connection.
Next: All a GIF does is look for a current imbalance between HOT an NEUTRAL. For this fault condition it does NOT even look at the ground. If there is an imbalance that means that current is flowing somewhere not intended. That usually is through a ground, but seldom through the ground on the plug.
Finally: Newer GFI also do trip if there is a ground/neutral connection since ground and neutral by code must not to be connected together anywhere but at the main service feed.

GFI are one of the ONLY code approved way to use a 3 prong outlet in a old house with two pronged ungrounded service. Use a GFI, connect the hot and neutral and put on a label that says :No ground connection" and your up to code. No ground required for proper GFI operation.

OK I owe wolf10 for his answer. Every home and CG has a 120/240V distribution system with 2 hots and a common neutral. If the neutral is open or partially open then you get high voltage on one hot and low on the other hot. A 30A plug is powered from one hot and the common neutral.