cancel
Showing results for 
Search instead for 
Did you mean: 
Senior Advisor

Trimble Guidance Issues

I am running a FM-750 monitor with the EZ-Steer system on my CIH 7140 tractor.  We are only using the free waas signal for our accuracy.  My problem is that my accuracy is oscillating from around 8"-10" of center from side to side.  I have recalibrated my T2 controller with no improvement.  At first I thought it was the nature of the free signal, but several of my neighbors are running the same system and tell me that their accuracy is only off from 2"-3".  The front end of  the tractor was completely rebuilt before I installed guidance system as to prevent a loose or sloppy steering system.  What setting can I change if any to reduce oscillating?  Currently I have angle per turn at 23 degrees, aggressiveness anywhere from 85% up to 100% & freeplay is set to 0 in both directions.  Any suggestions on what I can try next?

0 Kudos
8 Replies
Highlighted
Contributor

Re: Trimble Guidance Issues

What are you running for your GPS setup? Auto-Select or are you looking at WAAS 138 or WAAS 133? If you are having trouble with pass-to-pass that is where I would start. Also check the location of the GPS antenna.

0 Kudos
Senior Advisor

Re: Trimble Guidance Issues

I will need to check on the waas signal.  What is the recommended setting?  As far as the antenna, I have it mounted on the roof at the front middle of the cab.  This is where all antenna's in my location are mounted.

0 Kudos
Contributor

Re: Trimble Guidance Issues

What part of the country are you in? If you are in the east to the Missouri river WAAS 133 should be your satellite, if you are from the Missouri river to the west you should be on WAAS 138. As for the antenna placement where you have it placed is where i place all the antennas that i install.

0 Kudos
Senior Advisor

Re: Trimble Guidance Issues

I was able to check, and my GPS setup is on Auto-Select.  I am located west of Missouri right in Central Kansas.  While using the FM-750 monitor, I toggled thru the status screens and I think it said wass 138 is what was in use.  Tried to run EZ-Steer and it was oscillating 15" one side to 15" to the other.  Disengaged EZ-Steer and used GPS for guidance with manual steering.

0 Kudos
Contributor

Re: Trimble Guidance Issues

Make sure that the GPS source is set to WAAS 138. If that is set to 138 then check the vehicle setup, starting with the angle per turn. Default will be set at 20, for most early magnums it might vary between 20 - 22 or maybe a little bit lower, on the John Deere side this value will vary between 15-25 depending on model of tractor. Also check to see how the T2 is mounted. Make sure that is flat and mounted solid to the floor or on a steel mount of some sort. If the T2 can move just a tiny bit it may cause the steering to wander.

0 Kudos
Senior Advisor

Re: Trimble Guidance Issues

So I should change the GPS source from Auto-select to 138?  Am I understanding you correctly?  I've got the angle per turn at 25, I will back that down to 20 and reset aggressiveness to 100 and basically try again.  As far as the T2 box is concerned, that is one of the first things I checked and it is very secure.  I've got it mounted in the vertical position with the cables leading up to it from the bottom.  Is this an acceptable position?

0 Kudos
Contributor

Re: Trimble Guidance Issues

yes, change the gps source to 138. as for the t2 that is ok to have it mounted that way.

Tags (1)
0 Kudos
alange390213
Frequent Reader

Re: Trimble Guidance Issues

It is a an acceptable mounting position to have the cables down as long as the black cover is facing forward and the base is exactly at right angles to the centerline of the vehicle.  (it can be off the centerline but must be set at right angles. the back wall of the tractor is the only good place for the mounting if the cables are facing down.  try a little free play. make sure all the measurements are entered correctly in the setup. make sure you have the correct tractor type selected. check every setup parameter to make sure they are correctly entered.  It probably is some simple setup item that needs tweaking.

0 Kudos