Camper brakes

Bigred

I don't know if it is correct, but I had the same experience (I don't know enough to say it was a problem).
I had a electric brakes installed on a previous camper trailer & vehicle using a Tekoshona Voyager controller. I can assure you the manual override only applied mild to moderate braking to the trailer. The controller worked perfectly once set up (Power and Fine Tine knobs adjusted), but the manual override never locked the trailer brakes up.
Like you I thought it should have locked the relatively light trailer drum brakes up, but I accepted it and found that they worked still satisfactorily when applying the manual controller when descending steep gravel tracks.

Mark

6 volts will not lock the wheels, try increasing it up to 9 and see what happens.

The manual adjustment will only apply the voltage the controller is set at.

Setting it up to a point of locking brakes is pointless and dangerous, you want to set the controller only to a point where you can feel retardation.

A locked wheel has no stability or grip.

If you jack up the trailer and apply the foot brake (with the ignition on) and try to turn the trailer wheels they should lock up almost immediately. That will determine if they are working or not.

I do not know the controller well , but surly with maximum retardtaion set on the controller and the manual override activated you should get significant braking action..I would expect to lock up the wheels.

There may be some effect with bedding in the shoes because of the twin leading shoe arrangement and the mechanical braking advantage that supplies.....that advantage being dependent on friction in the shoes....but I would have thaught you should get pretty decent retardation right from the get go.

There are some articles and threads on adjustment and centering of the backing plates on electric drums that might be worth reading.

It might also be worth looking at the size of the wire used to wire the brakes...more frequently than not it is lighter than specified in the brake controller documentation.

it might be worth checking that the brake system in the trailer has been properly earthed to the earth pin on the trailer plug.....with adequate size wire.
I have seen brake systems dependent on the chassis earth.

OH and trailer assemblers are notorious for poor connection methods....check that any crimp lugs are the correct size for the wire a crimped with a decent crimper.....the lug should not pull off the wire under any circumstance.



As for why you would want to lock up the wheels......well that was the prerscribed adjustment procedure when setting up voyager controllesr that I am accustomed to.

the procedure was to..at low speed and on a flat road adjust the maximum braking effort using the override till the trailer brakes locked up then back off till they did not.....then adjust the leveling controll
tweak till sweet.

cheers

Bigred,

I have an original Prodigy, the model before the P2. They look identical, I don't know what the technical differences are.

FWIW, I have had exactly the same experience as Mark form Tamworth. With full voltage dialled up and full braking applied manually to my previous lighter van (1200kg), the van wheels would not lock up. But in a hard stop I heard my van tyres screech.

I now have a different van (2200kg) with electric over hydraulic brakes, same controller. with full voltage dialled up and full manual braking on just the trailer I get firm braking but no lock-up. I've had two emergency stops due to idiots - one a driver the other a pedestrian - and both times I think the van brakes came on harder than I could apply manually; I heard the van tyres screech a bit. On this van I always use 1 stage of Boost on tar and none on unsealed.

You mentioned in your Follow-up 820805 to Bantam that both shoes come on from the bottom. That to me would indicate one leading (self-servo) and one trailing, which might be appropriate for a light trailer, but not being as "aggressive" as twin leading, might not lock up with your controller. Your heavier caravan may have twin leading shoes and thus more self-servo action and able to lock up with your controller. This in addition to other factors others have mentioned, eg on your smaller trailer possible poor wiring size, possible bad earth, etc.

Cheers

I use a Voyager with the CT and the manual slide switch has never locked up the brakes yet they work fine on the auto setting.

Just one thing: don't do tests or make adjustments till the shoes have warmed up a bit.