Power voltage to brakes??

Gdetrailer wrote:

otrfun wrote:

Mmaxed wrote:

Gdetrailer wrote:
Believe it or not, your IBC is much better over any of the current aftermarket controllers even with some of the short comings of it.

Absolutely not true, if his Ram is like my '15 was from the factory.

Someone at Ram decided that below 30 mph the trailer brakes would only need about 60% input. On the bigger brakes, 12" x 3" if memory served it was dangerous. More than one fellow reported rolling through an intersection. Ram did update the programming. My 2020 has very good trailer braking.

Lot of discussion ref the shortcomings of the 2013-2016 Ram IBC a few years back. The IBC on our '16 Ram 3500 never provided more than 2.2a braking current at each wheel---even with every internal preset set for absolute heavy, maximum braking. Got a full 3a powering the trailer brakes directly via battery. The IBC worked reasonably well under normal conditions. However, for emergency braking---it was sorely lacking. Bypassed the IBC and installed a Tekonsha P3. Problem solved---3a at every wheel if/when needed.

And once again, you CAN'T have AMPS without VOLTAGE.

Part of the problem with not getting more than 2.2 AMPS is from WIRE RESISTANCE. RV manufacturers take the low road on wire size, using the smallest wire gauge they can get away with. Just because the wire gauge can handle the max current of the circuit doesn't always mean it is the best size to use. Even in 120V/240V AC circuits there is a wire size table that calculates to correct wire size for the distance. Once you pass a certain length the tables tell you to use a larger wire gauge.. It isn't done because the wire can't handle the current, it is done to reduce the voltage loss.

The smaller wire size, the higher the resistance, higher the resistance the lower voltage you get at the end of the wire.

This becomes even more of an issue with LONGER trailers where there is more wire involved which equals even more wire resistance.

More wire resistance equals lower voltage present at the brake magnets.

Lower voltage at the brake magnets equals LESS CURRENT DRAWN BY THE MAGNETS.

This is BASIC DC ELECTRICITY 101.

Some controllers may overcome SOME of the problem by being a bit more efficient electrically wise, but not ALL of the problem.

Replacing the IBC with aftermarket is simply putting a bandaid on the real problem.. But if you like fixing everything with bandaids, then go for it. I would rather tackle the problem without resorting to bandaids.

The problem is more on the TRAILER END than on the controller end and the ones that experienced not enough braking and fixed it with an aftermarket controller simply bandaided and hid the problem with the trailer wiring.

RV manufacturers are known to be cheap, they tend to use whatever leftovers they have. I had one RV that had no less than three factory splices from the trailer tongue to the first axle.. And that was on a 20ft TT.. Talk about being cheap! They basically took the cut off scraps of wire to build that trailer.. When I got that trailer the brakes barely worked. That's when I discovered the ugly truth. Every single splice had severe corrosion.

Just because I didn't mention voltage does not mean I did not measure voltage. You could have simply asked me what my voltage readings were and saved yourself all the time and energy elaborating on Basic Electricity 101. Since this seems to be a very sensitive issue with you I'll provide you with a bit more detail.

I measured voltage (using a Fluke 7-600 VM) and current (using an Amprobe 320 DC clamp-on ammeter) 12" from the brake magnets, so nearly ALL the losses in the trailer wiring were taken into account with these readings. Voltage always remained >12.0v with the IBC, battery, and Tekonsha P3 in circuit with maximum braking current applied to 4 brake assemblies (~2.2a/8.8a, ~3a/12a, and ~3a/12a, respectively; source battery voltage for IBC, battery, and P3 was 12.5 - 12.7v). Clearly, the trailer's wiring was more than adequate and *not* an issue in this scenario. I might add this particular trailer had approx. 20 ft of 10 gauge wire running from the 7-pin connector to the axles (2 axles, 4 brakes), which kept voltage drop <=5%.

In light of the above voltage and current readings, it is more than obvious the IBC was the limiting factor in terms of total braking current (~8.8a vs. ~12a), and *not* the trailer wiring.