Posted 12/5/2018 08:38 (#7150117 - in reply to #7149258) Subject: RE: Trimble Field IQ Rate control setup Question
Southern Minnesota Between Freeborn & Wells
JD8520 - 12/4/2018 21:18
Setting up my TMX-2050 in a JD 4700 sprayer with section control and rate control. The display will not allow me to choose PWM as a control valve on the P-IQ rate control page. Is it possible to control a PWM valve with this display on a JD 4700 sprayer?
I was using it to control rate and 12 sections on my JD 6500 sprayer previously using a Raven flow control valve. Bought the kit and wiring and had it dealer installed. I verified the wiring according to the field-iq installation instructions. Only used the section control last year with the Deere brown box controlling rate. I want to add more sections for next year.
Updated display to 5.6 firmware
I did this type of thing with a Deere 4720 sprayer and an Ag Leader system. This sprayer originally came with the brown box that was the display for spraying and other machine functions. I desired to add the Ag Leader system to 1) obtain auto section control 2) Produce onscreen coverage and rate maps 3) Control a Raven injection pump for direct chemical injection.
In my case it was not possible to have the Ag Leader system control the rate of the main product, this was still done with the original brown box. With the 4720, the section switches were rewired somewhat to become inputs to an Ag Leader Auxiliary Input module. This module informs the Ag Leader system which sections you have "allowed" to be ON. The Ag Leader system also included their Liquid Product Control module. This module has an input from a flowmeter and contains outputs to control the section valves and rate control.
The output from the Deere flowmeter had a tee cable installed that fed the flowmeter pulses to the original Deere system where it was used as usual. It also fed the flowmeter pulses to the Ag Leader system so it could compute the rate separately. The section outputs from the liquid module were feed to the wiring that had originally been connected to the section switches. The output from the control section was not connected to anything.
Since the Ag Leader system was "in the middle of things", it could shut off a boom section when it deemed appropriate. The Deere system would respond properly with the sections turning off and the Deere system adjusted the flow to achieve the proper rate.
This worked well for me. I did need to enter the target rate for the application into both the original brown box and the Ag Leader system. If for any reason, the flow needs to be changed (different rate, change in ground speed, section status change) both the original Deere system AND the Ag Leader system would try to correct the rate. Only the Deere system could affect the change since the Ag Leader output was not connected. If the Deere system was not able to correct the rate to stay within the target parameters, both systems would alarm.
I assume this is very similar to what you have done with the previous sprayer. In my case with the 4720, I don't believe I would have been able to handle more sections since the brown box was working with rate control, minimum and standby pressures etc. A foot master switch was also part of the Ag Leader wiring.
The Ag Leader Liquid Module does have the provision to run a PWM system but apparently there were other problems associated with using it for control.