Weatherproof trailer brake controller?

[John Mc]

Has anyone seen a trailer brake controller that is weatherproof? I'd like to be able to control the electric brakes on my forwarding trailer from my open-station tractor. I've occasionally been pushed around by the trailer when coming down hill and trying to keep the speed slow and steady. Keeping my studded "Euro-style" chains on the tractor year round certainly helps, but being able to get a little assistance from the trailer brakes would be handy.

I'd be operating the brakes manually, since there is no brake light circuit on the tractor (and being a hydrostatic transmission, I rarely use the brakes anyway.)

The previous owner just had an old automotive trailer brake controller and wired it to his tractor, using the manual override lever for trailer braking. The problem was that the controller is not weatherproof, so he had to remove it from the tractor when it was outside, and had to be careful if rain was expected when working with it. 

I'm hoping to find something weatherproof, so I don't have to remove it when the tractor is stored outside or if rain is coming.

[John Mc]

Just a simple on-off switch is not something I'd want to try, since that would just apply full voltage to the brakes any time it was used.

The things I've found or thought of so far:

• Make a weatherproof box to mount the controller in. Problem: access to the manual override switch if the controller is inside a box. It's possible I could trick this into working on the automatic circuit by wiring up a weatherproof switch to send a fake brake light signal to the controller, activating the controller's normal braking mode as when the brakes come on in a truck. Would heat build-up be an issue in the enclosed box? (Maybe not since this is low speed, and intermittant use?)
  
• Remote trailer mounted brake controller (seem to be getting popular in Australia and New Zealand). These are weatherproof, since they are designed to mount in an exposed area on the trailer. The croblem with these is that they run off a cell phone interface. Once set up, they will work without the cellphone in a normal on-road vehicle, but there is no manual activation without the phone. I might be able to trick this by wiring a switch to simulate a brake light coming on, activating the controller. They also all seem to be proportional braking, which is great for on-road use, but not so hot for work in the woods (proportional braking tends to get confused by rough terrain). They are also expensive.
  
• Wire up a weatherproof DC-to-DC buck converter of the appropriate rated amperage and activated by a momentary push button or switch mounted in a convenient place. I can find a number of 12V to 5V converters which are waterproof. It's not adjustable braking, but it would give me slightly less than half power to the brakes. It would be better to find one that takes 12V input with an adjustable output. The weatherproof ones are not adjustable on the fly, but at least I could find a reasonable brake setting for a loaded trailer and go with that, then still trigger it with a simple switch. I have found an adjustable one but it is far too low an amperage rating for my needs.
  
• A previous inquiry on a tractor forum suggested just wiring a fixed resistor to a weatherproof switch. An interesting idea, but I'd need a wirewound resistor with an appropriate power rating. With a three position switch, I could have a "low brake" and a "high brake" setting. I've not found a resistor that is weatherproof. Also concerned about heat dissipation and where to mount these resistors (these are significantly larger than what you see on a typical electronics circuit board.)

If anyone has any creative ideas - or knows of a good factory-made option - I'd appreciate hearing your ideas. In the mean time, I'll probably go with a cheap vehicle brake controller, try to keep it out of the weather, and remove it when not in use.

[doc henderson]

It just so happens I am replacing a transfer switch in my camper and putting in a new landline power supply.  there are waterproof boxes for wiring and plugs that easily flip up but shed rain.  you could develop muscle memory to lift the lid to operate, or mount so the lid is raised or removed during operation.  then a standard variable brake controller should work.  

you could also get a brake light switch and mount it for easy application and or rig a linkage to the override manual lever to be operated outside of the box.  thinking outside of the box.  

[beenthere]

If you have hydraulics available on the tractor (3rd SCV) that allows you to activate a small hydraulic ram that serves to engage the brakes, maybe a weather proof way to do what you want. 

[John Mc]

If you have hydraulics available on the tractor (3rd SCV) that allows you to activate a small hydraulic ram that serves to engage the brakes, maybe a weather proof way to do what you want.

Brakes are electric.

[beenthere]

I know that, but they are likely actuated by a solenoid pulling on a cable. Was just a thought.  

[customsawyer]

Put a ziplock bag over it, and zip it up close to the wires. When it gets a hole in it, put another bag over it. 

[teakwood]

real southerner solution Jake!