prodigy p3

Full power should be around 3 amps per brake.
It will be less if your wiring drops volts en-route.

I have a P3 and will see a variety of readings depending on what pressure Im applying. Generally from under 2 to around 8'. I have to admit most of the time when I'm braking I don't have my eyes on the controller but what's in front of me. I've had it installed about 2 years and am very happy with it.

With my two axle trailer which is 4 brakes I see about 1 amp per volt.

That is if the P3 is putting out 7 volts then with it in diagnostic mode you should see about 7 amps.

7amps is where my controller is set so full manual travel gives me 7 volts and about 7 amps.

Each morning before I leave I put it in diagnostic mode and check the amperage. 7 amps I am good to go.

Amperage is dependent on the draw of the total of the brake magnets and associated wiring. Voltage to the brakes is controlled by the P3. Your battery condition will have little to do with brake controlling as the vehicle's alternator will be delivering power to the P3 and back to the trailer's brake system.

Tekonsha advises an initial voltage of 6 V and adjusting up or down from there. An improvement in electrical efficiency for the trailer's brake system can be had by wiring the trailer braking in a star configuration rather than a daisy chain, as most trailers are OEM wired. This helps to deliver more power to the brakes. An increase in wire size accompanying the star configuration will also help with maximum electrical efficiency.

westend wrote:
Amperage is dependent on the draw of the total of the brake magnets and associated wiring. Voltage to the brakes is controlled by the P3. Your battery condition will have little to do with brake controlling as the vehicle's alternator will be delivering power to the P3 and back to the trailer's brake system.

Tekonsha advises an initial voltage of 6 V and adjusting up or down from there. An improvement in electrical efficiency for the trailer's brake system can be had by wiring the trailer braking in a star configuration rather than a daisy chain, as most trailers are OEM wired. This helps to deliver more power to the brakes. An increase in wire size accompanying the star configuration will also help with maximum electrical efficiency.

Etrailer.com indicates that trailer brakes are wired in parallel(star).
Parallel wiring
Diagram

If trailer brakes were wired in series (daisy chain) as you indicate, it would only require one brake magnet coil to open up and all of the breaking would be lost.

Thanks everyone. The main reason I traded up to the p3 (other than I really just wanted one), was due to the fact that when we bought our 2010 model 33' Rockwood tt used last spring, I would go through the brake setup adjustment per my current proportional brake controller but never could get it setup right. It said the same thing the p3 instuctions say I believe. Which is to initially set the controller to a certain power, manually fully engage the brakes at 25 mph, and if the brakes lock, back off the setting. If not, increase the setting, and so forth. Anyway, my old 25' tt would lock the wheels just like the instructions stated. My Rockwood won't even at full power. I'm thinking l have tt brake issues.

Since you bought your Rookwood have you removed each brake drum and inspected the brakes and bearings? Greasing or packing the bearings is a must since it is a 5 year old trailer unless you know they were packed just before you got it. You can either have all of this done or do it yourself. If you choose to do it yourself then you can Google "Packing RV trailer bearings" and "Adjusting RV trailer brakes" if you haven't done that before. I do all that kind of work myself because I trust me.

I have the Tekonsha P3 and am very pleased with it. Maybe one reason it doesn't slide the tires is because your newest trailer is a heavier trailer than your last one. I make it a point not to slide my trailer tires. You want enough braking on your trailer to be balanced with your tow vehicle for good controlled stops.

Edit: One more thing I thought of is to check the electric braking action. With the wheel jacked up and the trailer cable connected to the TV, spin the wheel to check for easy turning. Now have someone press the brake pedel while you check to see that the wheel is locked.
Do this check for all 4 wheels. Keep safety upper most in your mind while doing this.

Anytime you buy a trailer new or used I recommend inspecting the brakes and bearings.

I was having problems with my new trailer and when I removed the brake drums I found three torn grease seals and grease every where.

I had to replace the brake assemblies as my dealer only wanted to clean the brake shoes and replace the seals.

Brakes are very important and if you are capable of doing the job I am positive you can do better than most dealers.

Yeah, I think the next step is to pull all 4 wheels and do a thorough inspection and see what I'm dealing with . The last thing I want is 33 feet of trailer pushing me through a red light. Or worse. Thanks for the input everybody.

Bigbird65 wrote:

westend wrote:
Amperage is dependent on the draw of the total of the brake magnets and associated wiring. Voltage to the brakes is controlled by the P3. Your battery condition will have little to do with brake controlling as the vehicle's alternator will be delivering power to the P3 and back to the trailer's brake system.

Tekonsha advises an initial voltage of 6 V and adjusting up or down from there. An improvement in electrical efficiency for the trailer's brake system can be had by wiring the trailer braking in a star configuration rather than a daisy chain, as most trailers are OEM wired. This helps to deliver more power to the brakes. An increase in wire size accompanying the star configuration will also help with maximum electrical efficiency.

Etrailer.com indicates that trailer brakes are wired in parallel(star).
Parallel wiring
Diagram

If trailer brakes were wired in series (daisy chain) as you indicate, it would only require one brake magnet coil to open up and all of the breaking would be lost.

Yes, parallel but crawl under your trailer and see what you have. Most trailers have one power wire that is led from the tongue, then from one brake set to another and down the chain. A star configuration uses one wire set per brake. The four power wires are terminated at a common power terminal close to the tongue. It is a better power configuration than the typical wiring installation.