dmarkh
Full Access Member
Correct, it uses inertia. Just like a surge brake system on those uhaul trailers.
Ive towed my truck up and down mountains and have not experienced any issues with engine braking and the truck brakes overheating.
I just read this from https://www.trailerlife.com/towguides/controlling-trailer-brakes/
An inertia-based proportional controller generates an output that is, as the name suggests, directly proportional to your braking needs. Most proportional brake controllers measure the tow vehicle’s rate of deceleration by means of a pendulum. The quicker you slow, the further the pendulum is displaced, via inertia, from its at-rest position. This creates an electric signal to your trailer’s brakes that is proportional to your deceleration rate. Tekonsha and its sister companies use a series of LEDs and photoelectric detectors in their proportional controllers to determine the position of the displaced pendulum, and therefore determine the deceleration rate. Hayes-Lemmerz uses the Hall effect, a well-known physics principal involving moving magnets, to determine the pendulum’s position. All pendulum controllers are subject to some inaccuracies, as the pendulum can tilt slightly forward or backward on steep grades. Most such controllers employ a damping device to stabilize the sensor against vibrations, and the damper helps reduce the effect of the fore-or-aft-tilt problem. The pendulum’s position is adjusted through the level-control knob. This allows the pendulum to be oriented to a true vertical resting position to compensate for the angle of the brake-controller body (the “leveling” referred to in some timer-based-controller advertising). The level adjustment also allows the driver to pitch the pendulum slightly forward or aft of its normal resting position to set up the trailer so its braking is aggressive or delayed.
So it's possible that the RViBrake3 is smart enough to know you are on a long down grade and handle it correctly. If I'm not mistaken this technology is in every modern cell-phome today.