I've been doing some research on 'Break Away Switches'

Federal traffic safety law specifies that all trailers that are required to have brakes, shall have a means of activating the trailer brakes under trailer break away conditions. 

Specifically, 49CFR393.43 Every motor vehicle, if used to tow a trailer equipped with brakes, shall be equipped with means for providing that in case of breakaway of such trailer the service brakes on the towing vehicle will be sufficiently operative to stop the towing vehicle.

In order to have a break away switch you need three things:
1. A battery on the camper.  Once it becomes disconnected from the tow vehicle you will need a source of electrical current back there.
2. Electric brakes installed on the trailer.  This method will not work with surge brakes, so if you have surge brakes you can stop reading now.
3. The switch itself, which is available at most RV dealers and parts places. The switch will be a normally closed switch, which has a plunger inserted to open the switch.  When the plunger is pulled, the switch closes and current flows.

To hook up the switch connect a wire to the positive terminal of the battery, or tap a new wire into one that is already there. Connect this new positive wire to one side of the switch. Connect the other side of the switch to the wire you identified that activates the brakes.  For this system to work there is no need for a negative wire as both the brakes and the battery use the frame as a ground.

Leading off the plunger is a cable.  When hooking up your camper for towing, this cable should be connected to some part of the tow vehicle.

Hope this help someone?