Dell Venue 11 Pro - charging

This was my first day actually steering the combine with my single GPS setup. I found that I can’t keep the tablet charged while using it. It started at almost full charge and only took a few hours till it was dead. The entire time it showed that it was plugged in and charging but the battery percentage slowly went down. I’m using on micro USB cord that I cut off and I’m feeding it 19 to 20 volts with a booster. My previous bench testing show that it could charge the battery and power it. I checked my booster’s output voltage while the tablet was on and I was maintaining my set voltage so I don’t think my booster was being starved of input power. I have not checked how much current it used but it seems as though the tablet isn’t detecting it to be a high-wattage charger. When I was testing it on the bench, as soon as I reached 19 volts on my booster then the tablet in the bios showed that it was a high-wattage charger.

Did your charger output 1.2 A at 19.5 V ? According to DELL, this is yow you get the maximum charge speed. If you didn’t have the same issue while on the bench, it may be because your new voltage regulator can’t output as much current, or because the tablet doesn’t want to use it.

I’m using the same booster in the combine as on the bench. I don’t know how to make the tablet use more current but it could be that at first connection, it can’t supply enough current and so the tablet tries to charge at a low charge rate.

To confirm this, maybe try to measure the current while in the cab.

I had this issue too and i stoped a driver in the device manager but i can’t remenber wich.

My tablet charger is working 100% today after I connected my booster’s input to a steadier 12v, more direct to the battery instead of the cab’s accessory power.

So the incoming power to the booster was the issue?

Yes, that appears to have been the problem.

I use the targus charger

https://www.ebay.de/itm/293706977782

I can’t find that part number (APD038U) anywhere else but I find these two. First one looks the same.
https://www.ebay.ca/itm/324104743460

I’ll test my booster some more and try a smaller one yet (currently using a 150W booster).

This charger:

It’s compatibile with dell 11 pro 7140?

No you need one with a micro usb cable, or adapter to plug in the dock port at bottom of the 7140.
7140 Venue 11 will charge on 5v USB but only with 3W which is not enough for keeping power when in use (will drain battery during the day. Could be enough with full battery in the morning)
Maybe one like this is right: https://www.ebay.co.uk/itm/353140271605

Thanks.
So with Targus the battery won’t drain if i use the tablet all day?

I was successful by cutting off a usb micro connector, boosting the tractors 12v to 20v and connecting that to the red & black wires from the usb micro. I verified the correct polarity with a continuity test while the usb micro was plugged into an Arduino with usb micro. The first plug I cut off didn’t work for some reason, maybe it was data only. Your booster needs to comfortably handle 90W, so 4-5 amps. One thing I notice with my setup is that while starting the tractor, I think the voltage dips to much for the booster and sometimes the tablet disables high power charging until I unplug and replug in the charger.

I also have a dell venue 11 pro. When runnig simulator i have no problems. But whem live i see it is really slow and controller communication is dropping. Anyone have idea why??

Have you set the performance bar to maximum from the battery settings in the lower right corner?

No i have not. But it should be able to run v5 latest?? With out any problems??

I ran v5 no problem on mine. Maybe sure performance is set to max/high and that you’re charging it with a 20v 90w supply.

Thank you for you information.

Does it make a big difference in processor.

Mine had the Intel core M-5Y10. Instead of the M-5Y71