USB resets and drops when steering

I had this happen a couple times at the end of last season, but now I can’t get 10 seconds of steering before I get the USB resetting and lost connections in AOG. Have to power down the system to get them to reconnect , sometimes have to unplug USB or restart toughpad.

I’m using the usual PCB v2 that I’ve run for a couple years now, with a USB nano for autosteer and USB GPS (m8t). I also have this same thing happen if I leave USB plugged in when I power up the board. I’ve swapped motor drivers, nano, USB hub, GPS module and nothing’s helped with it.

I don’t see any power fluctuations but its possible its cycling the relay really fast and that’s what’s doing it? I havent checked the PCB to see if there’s flyback protection on the relay.

did you change something aboute wire or Usb Hub?

Dodgy ADS or IMU messing up i2c? The arduino doesn’t like i2c trouble, and Agio (if you’re using v5) definitely doesn’t like arduino trouble.

Haven’t changed anything with the modules there, and tried a couple of hubs. I know what you’re saying about i2c but nothing should have changed. I am using a different wheel sensor, the stock 0-5V WAS on the 7630 but that seems to be fine as long as I don’t engage the steering motor. I have no idea how the filtering is on the steering outputs, maybe something is coming back on that.

Definitely 0-5v and not 4-20ma?

Well, after tearing everything down and rebuilding it from the ground up, I used a third USB hub fresh out of the box, and it seems to be going on fine now. Just have to rewire everything I tore apart troubleshooting and hopefully that’s the fix. Looking forward to figuring out what I need for version 5 and full UDP instead of these USB devices.

This is not the first hub I’ve had die on this setup, but it’s the first time replacing it the first time didn’t fix the issue so I started searching around.

Thanks for the help, Alan. Lesson is, even your backup can be bad.

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I’m on my third hub and am going to UDP with my latest setup when I can get it working. I avoid USB3 hubs as they are particularly troublesome. They can cause all sorts of interference. My gps goes all over the place when I fit a USB3 hub.

RFI is a known issue with USB3.

It doesn’t sound like quite the same symptoms, but I was having USB connection trouble with the steer module.

Eventually I realised that this only happened when the laptop was plugged in to the charger, which was on a lighter socket plug. Cut the plug off and powered the charger via the V2 board and it seems to be fine now.

I don’t think the one I tried was a 3, can’t really tell now as I shucked them to reduce space, and tossed the remains.

I initially had figured RFI and put a metal sheet between them and the motor driver, then entirely removed the driver away from the hub, but that didn’t seem to help. Then I thought maybe backEMF was getting it and used one of those impregnated donuts on the devices.

I think half of those lighter socket chargers are probably directly responsible for tractor fires. They’re absolutely terrible.

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You absolutely need single point grounding. All the ground connections need to come back to a termination spot that then goes to the battery.

Tractor grounds cause excessive noise. This was rule #1 for every installation - and is easily forgotten.

So, A big fuse right at the positive terminal, then 2 heavy wires positive and negative to a termination block in the cab. Here, make sure none of your devices are grounded anywhere else, are the connections made to ground and power all your gps, laptop, modules etc. Be sure your steer motor power has its own wires to the termination block or if using the 12 to 24 volt convertor, mount close to that block and don’t skimp on wire size.

Do not use cigarette lighters, accessory power from a fuse box, none of that.

Doing this, your system will never crash.

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Yep, nothing quite like making a well known mistake for yourself to drive it home. I had got everything else connected with the common earth, but had managed to forget about the charger.

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Interesting point on using a separate power lead for the steering motor, I’m not doing that, I’m just using separate outputs of the 6-outlet JD accessory strip for autosteer, tablet and steering motors, and I imagine they’re all on the same fuse. That said, even with a fuse you should see any interference transferred across the complete tractor power bus because I dont think there’s any sort of filtering in the fuse block.

I’ve got a single point with two fuses. One for electronics, one for the motor. Fast high speed direction changes will cause high current spikes with corresponding voltage drop even in well designed systems.

My 12 - 23v converter has variable current limiting which goes a long way to softening this effect. Also makes life easier for the motor and associated equipment.

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Its a good idea to run a separate fused line and ground for motor drive.

That didn’t even do it. I eventually moved the motor driver to a deep cycle battery in the cab by itself, which fixed multiple problems. I had steering creep where it would slowly move left then snap right every 5 seconds, a constant 3’ gap on left side and overlap on right for the entire field and uturns were an unreliable disaster. As soon as I isolated the driver, I could dial everything in and it was perfect.

Strangely though this all worked fine in the other tractor it was installed in before. Maybe I hurt something in the move and it started this failure chain.

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