Hi,

New to the travel trailer world and am setting up my trailer as a "destination" camper at a partially improved campsite. We have city water, a sceptic system and I have power to an entry pole. I am going to have an electrician run power from the entry pole about 160 feet to 2 gravel pads that a buddy and I have made, and have asked him to hook up a standard 50A/30A/20AGFCI RV pedestal at each pad. I have solicited 3 bids, and they're very close in price, but I don't know what I don't know....and I know that I've always paid someone to deal with electricity because I don't want to get fried. Now I'm more concerned about frying my trailer... Two bids are using 4 strand 4/0-4/0-4/0-2/0 and one bid proposed 3 strand 4/0-4/0-2/0 with a ground rod at the trailer. I'm using a Progressive Industries 50A surge protector at the pedestal of my trailer. Questions:

1. Which type of wire (4 or 3 strand) do I want and why?

2. Even with a grounding wire in the supply line, do I need to run a grounding rod from the trailer frame?

Thanks in advance!