I would have to be in a serious research mode to find that out. The only way I can think of would be to hook up to the TT, cancel any IBC and then chart the amps at a fixed number of test pressures. Then go back and program in an amp of IBC and then try to hit the exact same pressures and record the output. Each point should be one amp higher across the board if the tech was right. Hmm. I'll take a shot at it this weekend sometime.
chadsalt wrote: Hypothetical; if the IBC is set to provide 1 amp, and the gain provides 3 amps at 400 psi.......why cant the gain just be set to 4 amps at 400 psi?
If I understand your question correctly --
The purpose of the IBC is to allow the TT brakes to "lead" the TV brakes. IOW, the IBC feature provides current to the TT brakes upon activation of the brake lights and before any discernable TV braking force. The 1 amp of current at zero (or near-zero) psi is what causes the "lead".
If you left the IBC at zero and just set the gain to produce 4 amps at 400 psi, there would be no "lead".
chadsalt wrote: Hypothetical; if the IBC is set to provide 1 amp, and the gain provides 3 amps at 400 psi.......why cant the gain just be set to 4 amps at 400 psi?
If I understand your question correctly --
The purpose of the IBC is to allow the TT brakes to "lead" the TV brakes. IOW, the IBC feature provides current to the TT brakes upon activation of the brake lights and before any discernable TV braking force. The 1 amp of current at zero (or near-zero) psi is what causes the "lead".
If you left the IBC at zero and just set the gain to produce 4 amps at 400 psi, there would be no "lead".
Ron
That's not quite what I was getting at. With the mechanical proportional controllers, and not getting into a "lead" discussion again, the distance between the brake light coming on and actual pressure being developed is pretty small. Most of the "lead" arguments arise between the electrical proportional and mechanical proportional camps.
What it appears people are trying to do (specifically with the mechanical proportional) is get the trailer brakes on sooner or actually braking harder than the truck to get that "lead" feeling.
What caused my interest is willard stating he was unable to get acceptable performance with the Maxbrake due to lack of some sort of IBC feature and then roln stating his Brakesmart's IBC setting only applied .2 amps.
.2 amps, even across the whole brake event, is not very much......sort of reinforcing my belief the IBC shouldn't be necessary. The only Brakesmart I've used had no IBC set and it performed fine. IBC is not available on the Maxbrake or factory controllers AFAIK. My Maxbrake performs fine with all my trailers. And I have yet to read a complaint about a factory controller relative to this discussion.
I guess my point is unless you are expecting a heck of a tug from the trailer when you just barley touch the brake pedal, I don't see why the gain simply couldn't be turned up to accommodate unified, or even trailer bias, braking between the truck and trailer.........which I thought was the point of a 'true' mechanical proportional controller.
Inquiring minds want to know. Maybe a poll relative to Brakesmart users and their IBC setting is in order?
I love to read all these threads on fiddling with brake controllers and how to adjust them along with where to put them so you can actually use the manual feature w/o taking either your hands off the wheel or looking down and away from the road. Below is what I have used for the past 30 years and IMHO is the best.
This is the brake controller and it slips onto the brake pedal and works like a sewing machine pedal and I can get a full 9 Amp with zero TV brakes or no TT brakes and full TV brakes.
AND I monitor the amerage to it with the following that sets on my dash in my field of view of the road. The meter on the left shows the amperage going to my trailer brakes and is great to make sure they are all working correct before leaving since each brake magnet draws 3 amps.
Larry
2001 standard box 7.3L E-350 PSD Van with 4.10 rear and 2007 Holiday Rambler Aluma-Lite 8306S Been RV'ing since 1974. TRAILER MODS
chadsalt wrote: That's not quite what I was getting at. With the mechanical proportional controllers, and not getting into a "lead" discussion again, the distance between the brake light coming on and actual pressure being developed is pretty small. Most of the "lead" arguments arise between the electrical proportional and mechanical proportional camps.
What it appears people are trying to do (specifically with the mechanical proportional) is get the trailer brakes on sooner or actually braking harder than the truck to get that "lead" feeling.
I believe the idea behind "lead" is to get the TT brakes to come on sooner. With the Jordan or Prodigy or BrakeSmart, you can get some TT braking even if there is no discernable TV braking.
Quote: I guess my point is unless you are expecting a heck of a tug from the trailer when you just barley touch the brake pedal, I don't see why the gain simply couldn't be turned up to accommodate unified, or even trailer bias, braking between the truck and trailer.........which I thought was the point of a 'true' mechanical proportional controller.
Part of the problem might be that there is no fixed relationship between brake pedal travel or brake line pressure and braking force.
The relationship depends on condition of the pads/shoes, condition of the rotors/drums, brake temperature, condition of the tires, and friction between tires and road. On the TT end, there is no fixed relationship between controller current and braking force for similar reasons.
Even if a controller can be "balanced" for some conditions, it will not necessarily be balanced for all conditions. Some of the time the TV will brake harder than the TT, and some of the time the TT will brake harder than the TV.
If a user wants to ensure that the TT is never allowed to push against the TV, IMO the best assurance is to have the TT brakes "lead" (in time) the TV brakes.
I believe the idea behind "lead" is to get the TT brakes to come on sooner. With the Jordan or Prodigy or BrakeSmart, you can get some TT braking even if there is no discernable TV braking.
Ron
I submit that the gain can be adjusted to essentially cause the trailer brakes to "lead".
I.E. brake line pressure = 100 psi, not really enough to stop the truck but enough to activate the controller. Shouldnt the gain be able to be set to provide enough power to begin slowing the trailer?
I am able to effect this type of "lead" using only the gain on my MaxBrake. I personally dont care for the trailer to pull against the truck, but it can be set that way.
chadsalt wrote: I submit that the gain can be adjusted to essentially cause the trailer brakes to "lead".
I.E. brake line pressure = 100 psi, not really enough to stop the truck but enough to activate the controller. Shouldnt the gain be able to be set to provide enough power to begin slowing the trailer?
If your TV braking system has a 100 psi "dead zone" (i.e. does not produce any braking force until the pressure exceeds 100 psi) and if the brake controller is able to produce some TT braking force at pressures below 100 psi, then the system would be capable of producing TT braking force before the TV is producing braking force. The Jordan can work this way except that the "dead zone" is in the pedal travel.
If the BrakeSmart worked as described above, then it would seem that there would be no need for the IBC feature. I suppose its possible that the BrakeSmart's pressure transducer might not be sensitive enough to produce a usable output if the braking system pressure is in the dead zone.
If the MaxBrake has a sensor which is sensitive enough to produce a usable output when the pressure is in the dead zone, then that could explain why you can get a "lead" without having an IBC-like feature. Or, perhaps the MaxBrake does have an IBC-like feature with no provision for adjusting it,
chadsalt wrote: The MaxBrake has no type of IBC, when in sleep mode the unit will not "wake up" until there is pressure at the sensor.
The MaxBrake online brochure states:
2. Insert power connector, and signal cable. One wire to the
battery, one wire to the ground, one wire to the brake switch,
and one wire to the back of the vehicle to the trailer plug. You
may use the direct plug in method for vehicles equipped with
tow packages. You’re now ready to Calibrate MaxBrake™....
Do you know what is the purpose of the wire which is connected to the brake switch?
chadsalt wrote: The MaxBrake has no type of IBC, when in sleep mode the unit will not "wake up" until there is pressure at the sensor.
The MaxBrake online brochure states:
2. Insert power connector, and signal cable. One wire to the
battery, one wire to the ground, one wire to the brake switch,
and one wire to the back of the vehicle to the trailer plug. You
may use the direct plug in method for vehicles equipped with
tow packages. You’re now ready to Calibrate MaxBrake™....
Do you know what is the purpose of the wire which is connected to the brake switch?
Just trying to understand how the MaxBrake works.
Ron
No I do not. Since the MaxBrake does not illuminate the brake lights with application of the manual slide, I have no idea. It does use the same plug and play connector as the Prodigy/P3, maybe is was just easier to use a "standard" 4 wire connector?
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