Electric Brake Controllers
A number of different brake controllers are available, some of which contain pendulums, and must be mounted level and some which are transistorized and can be mounted at any angle.
There is also a “Self- Activating” controller on the market which is fitted to the “A” frame of the trailer and wired to the brake lights of the vehicle. These are not recommended for caravan towing as they cannot be adjusted or manually activated in the case of an emergency from the driver’s seat. (Extract from 2010 Caravanning Qld Magazine).