What happens if you hook up to a 3 axle trailer with a 2 axle brake controller?

[brobeson]

Does it still work, but not as much power?



Does it not work at all?



Does it damage either the trailer brakes or the controller?



My controller is a 2-axle controller, but I want to tow a 5er with 3 axles.



Should I get a new controller first?



TIA



Bob

 

[Guest00]

Spend the $75 and get a new controller. The cost of a 4 or 6 axle controller is the same as a 2 axle, Go for it and be ready for any thing. The 4 or 6 axle controllers will out put higher amperage, This is also good if used on 1 or 2 axle brakes as you can really heat em up in an emergency.

mho

 

[Rambling]

You'll burnup the current regulator in the controller at some point. Maybe not on a couple of stop-go situations but mostly on a sustained hold. As suggested, best to be safe and get a replacement. $0. 02

 

[Glen]

Smoke, lots of smoke. . . then no trailer brakes!

 

[sam peterson]

the controller doesn't know how many axles it is hooked to . if it has the capacity to work only two axles it will still work on 3 or more ,it just won't put out as muck power to each magnet, thus not as muck stopping power. no harm will be caused to the controller. each magnet on the trailer require approx 3 amps for full braking. if this tow is a 1 shot deal you may get by but if you are in dought or will need it later go with a higher capacity controller----Sam

 

[WestTN]

Brake controllers

Electronic parts aren't real smart. If asked to work into a lower impedance than they are designed for they will try to do their best. This leads to overheating. The controller could fail under load if it really is overloaded. It follows that this is even more likely to happen on a heavy braking application. That's the worst time to have a failure.

You didn't say what model you controller is. Are you sure it is only good for 2 axle brakes? If so, I would definitely replace it.

 

[sam peterson]

how does this account for the fact that you can increase or decrease the output any time you want by adjusting the gain control?

 

[WestTN]

brake controller

It isn't quite the same thing. The output transistors in the controller have a current limit. In electronics it is very seldom that you will find a 50% safety margin. !0% is frequently the norm. Even though the controller is a chopper circuit which regulates the total current flow, it does not regulate the instantaneous current value, which would be 50% higher than the component sevice ratings if the controller is in fact a 2 axle unit being used with three axle brakes.

Have you tried to stop a three axle trailer without brakes? I haven't, but when the plug dislodged on my 7700 lb two axle travel trailer, I considered myself fortunate to be able to stop it without incident before starting down that 6% grade on a small state highway in the Rockies a few years back.



For my two cents, I will always have a properly rated and properly installed inertia sensing brake controller in my truck and a small bungie cord wrapped around the plug to make sure I can stop.

 

[sam peterson]

WestTN--I fully agree with you. There is no substitute for having the best possible setup for the trailer brakes. there are to many rigs on the road with inadequate stopping power. lots of trucks suffer braking problems due to trailers that are not properly setup. you can,t have to much brake.