First let me lay out the most common theories of what position control is that I have run into most frequently.
Theory #1: Position Control is nothing more or less then the ability to stop the 3pt hitch at any point in the length of it's travel. For the sake of this discussion this will be referred to T#1
Theory #2: Position Control is the mechanism or scheme by which the 3pt hitch can be set to a predetermined height repeatedly with out the need to make fine adjustment. Think, set it and forget it. For the sake of this discussion this will be referred to as T#2
Theory #3: Position Control is a "Self Regulating Circuit", that automatically adjusts the height of the 3pt hitch. This automatic adjustment is needed in order to correct "Drift", that is the droop of an implement, that occurs due normal and acceptable leakage. For the sake of this discussion this will be referred to as T#3
I hope we can all agree that these three theories are expressing completely different ideas, and are mutually exclusive.
This topic has been discussed in several diffident threads. But to me, it always seems that there are folks that weigh in that feel that they are absolutely correct in their understanding of what Position Control is. This is not a criticism. I say this only to illustrate the problem it creates for folks that don't yet understand. If I, as a representative of the group that "Does not Know", accepts the certainty of Authority #1 that T#1 is correct. Then what am I to make of Authority #2 and #3 who are equally as certain that T#2 and T#3 are correct. From my perspective, and although I respect the experience of each of these authorities upfront, I can't reconcile the Fact, that all 3 theories can not be simultaneously correct. So although Authority #1,2 and 3 are "Certain", I am not.
Id like to respond to some comments made in another thread that sparked me to create this one.
Bullitt said:
The question is, what do you mean by "Position Control". If, by position control, you mean T#1. Then That is saying one thing.
IF however, when you say "Position Control", you are speaking about T#3, then that is saying something totally different.
So, I take this:
To mean that you consider "Position Control" as something that is Void of this "Self Regulating Circuit". Or at the very least, does not require such a circuit to be considered position control.
Further, I take this quote from Grandad:
To be supporting testimony.
If I am understanding both of you (Correctly), Bullitt and Grandad4, then there are a few things that can be taken away from this.
1) Pretty much all modern tractors have the ability to stop the 3pt hitch at any point in the full length of it's travel, thus pretty much all modern tractors have "Position Control". I try not to speak in absolutes, so that's why I say "Pretty Much".
2) Drift, or the process of drooping due to "Acceptable Leakage", is normal, but in a properly working system should be very slow, on the order of days at least to have any noticeable or significant movement, which essentially means in practical terms, there is no need for a "Self Regulating Circuit". Because any operation you may be doing, be it raking, tilling and so on, will not be done on a time scale where "Normal Drift" will have any appreciable affect on that operation.
That said, I feel that at least Grandad4 and Bullitt are proponents of T#1. I too feel, or at least felt at one time, that this was an accurate description of PC. Now, I simply can't be certain. and the reason why is this. I have heard supporting testimony from a fair selection of people that "SHOULD" understand the true nature of PC. Dealers and Brand Representatives that subscribe to one or a combination of the 3 theories listed above. The only certainty that I have is that they are NOT all on the same page.
I am not here to personally prove what the true nature of PC is. But I would like to see a constructive conversation from the various proponents of the differing theories above. Depending on what you choose to accept as factual, I have heard convincing explanations for at least two of the theories listed above.
Theory #1: Position Control is nothing more or less then the ability to stop the 3pt hitch at any point in the length of it's travel. For the sake of this discussion this will be referred to T#1
Theory #2: Position Control is the mechanism or scheme by which the 3pt hitch can be set to a predetermined height repeatedly with out the need to make fine adjustment. Think, set it and forget it. For the sake of this discussion this will be referred to as T#2
Theory #3: Position Control is a "Self Regulating Circuit", that automatically adjusts the height of the 3pt hitch. This automatic adjustment is needed in order to correct "Drift", that is the droop of an implement, that occurs due normal and acceptable leakage. For the sake of this discussion this will be referred to as T#3
I hope we can all agree that these three theories are expressing completely different ideas, and are mutually exclusive.
This topic has been discussed in several diffident threads. But to me, it always seems that there are folks that weigh in that feel that they are absolutely correct in their understanding of what Position Control is. This is not a criticism. I say this only to illustrate the problem it creates for folks that don't yet understand. If I, as a representative of the group that "Does not Know", accepts the certainty of Authority #1 that T#1 is correct. Then what am I to make of Authority #2 and #3 who are equally as certain that T#2 and T#3 are correct. From my perspective, and although I respect the experience of each of these authorities upfront, I can't reconcile the Fact, that all 3 theories can not be simultaneously correct. So although Authority #1,2 and 3 are "Certain", I am not.
Id like to respond to some comments made in another thread that sparked me to create this one.
Bullitt said:
With position control with the tractor running and 3PH lever left in one place the 3PH will not drift down.
The question is, what do you mean by "Position Control". If, by position control, you mean T#1. Then That is saying one thing.
IF however, when you say "Position Control", you are speaking about T#3, then that is saying something totally different.
So, I take this:
With a neutral lift after hours with a heavy load you may notice some leakage but very very very minimal if everything is working properly.
To mean that you consider "Position Control" as something that is Void of this "Self Regulating Circuit". Or at the very least, does not require such a circuit to be considered position control.
Further, I take this quote from Grandad:
+1 What he said. Any tractor, regardless of what type of lift control the 3 pt has, should not "drift" down so you have to re-adjust it all the time. If it's doing that, there is something worn or leaking in the hydraulics.
To be supporting testimony.
If I am understanding both of you (Correctly), Bullitt and Grandad4, then there are a few things that can be taken away from this.
1) Pretty much all modern tractors have the ability to stop the 3pt hitch at any point in the full length of it's travel, thus pretty much all modern tractors have "Position Control". I try not to speak in absolutes, so that's why I say "Pretty Much".
2) Drift, or the process of drooping due to "Acceptable Leakage", is normal, but in a properly working system should be very slow, on the order of days at least to have any noticeable or significant movement, which essentially means in practical terms, there is no need for a "Self Regulating Circuit". Because any operation you may be doing, be it raking, tilling and so on, will not be done on a time scale where "Normal Drift" will have any appreciable affect on that operation.
That said, I feel that at least Grandad4 and Bullitt are proponents of T#1. I too feel, or at least felt at one time, that this was an accurate description of PC. Now, I simply can't be certain. and the reason why is this. I have heard supporting testimony from a fair selection of people that "SHOULD" understand the true nature of PC. Dealers and Brand Representatives that subscribe to one or a combination of the 3 theories listed above. The only certainty that I have is that they are NOT all on the same page.
I am not here to personally prove what the true nature of PC is. But I would like to see a constructive conversation from the various proponents of the differing theories above. Depending on what you choose to accept as factual, I have heard convincing explanations for at least two of the theories listed above.