[rohrmann]

It’s possible that you have a bad electrode and it’s shorting out. If you are checking voltage across the two terminals at the exposed electrode connections and are getting anything else but 120 volts more or less, then you may have an open circuit on the junction box on the side of the water heater, usually only accessible by pulling the water heater out. You may need help with this, like a mobile RV tech. You may have a failed connection in the junction box which could be causing the breaker to trip.