Any auto electricians present?

Pepsi

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I am confused, more so than what would be considered normal.
I have a Samsung Active 3 Tablet which I use on a Husqvarna FE350 as a navigational device with OS Maps for green lanes etc. The device is connected to the bikes battery via a USB cable which is in turn plugged into an inline fused (2amps) cable, the sort you’d use for your heated clothing etc. I have no other devices connected to the bikes battery.
The bikes battery will start to charge the tablet once the cable is connected to it, however as soon as I fire the bike up, the tablet stops charging.
If I connect a power bank to the tablet via the same USB cable, the tablet charges.

Can anyone suggest why the tablet would stop charging as soon as the bike is started?
 
Forget the tablet for now. Is the bike’s battery charging? What is the battery voltage before and after starting?
 
Are you connecting the tablet direct to the battery i.e. with no intermediary drop down to the more conventional 5V for USB?

Googling suggests a Samsung tablet can fast charger at 11V via USB-C, although I have not looked at a specific data sheet for your model.

If you are not regulating the voltage from the battery /alternator then I suspect the tablet is happy at the resting voltage from the bike battery 12.5-13.5V but is not happy once the alternator kicks in at 14.5V typically, so shuts down the USB port.
 
Greg Masters said:
Forget the tablet for now. Is the bike’s battery charging? What is the battery voltage before and after starting?
Click to expand...
I’ve no means to test the battery voltage however the battery seems in good order, I can leave the bike for weeks and it always starts first time.
 
wessie said:
Are you connecting the tablet direct to the battery i.e. with no intermediary drop down to the more conventional 5V for USB?

Googling suggests a Samsung tablet can fast charger at 11V via USB-C, although I have not looked at a specific data sheet for your model.

If you are not regulating the voltage from the battery /alternator then I suspect the tablet is happy at the resting voltage from the bike battery 12.5-13.5V but is not happy once the alternator kicks in at 14.5V typically, so shuts down the USB port.
Click to expand...
This sounds suspiciously like you might be onto something.
The USB lead from the tablet is plugged into a cable with an inline fuse which in turn is then connected to the battery, is that what you mean in your first question? I thought these cables automatically reduced the voltage to accessories.

Your comment regarding the USB port shutting down at 14+ volts sounds very feasible, so do you have any suggestions as to how I can resolve this?
 
As Wessie also suggests, you need to know what is going on with the voltage at the battery - ie the effective point of connection of your device.

Buy a cheap multimeter!
 
Ignore the image down below it is the wrong cable. The cable I’m using is further down in this thread.
 

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Pepsi said:
This is the connector I’m using.

View attachment 316858
Click to expand...
Well there is no drop down resistance on that! That's just a female power connector for the likes of a heated jacket

What does the rest of the cable/connections look like ??

Somewhere along the way you need to get a brand new Digital Volt meter (£15.00) or borrow one that you know is in spec

Check battery volts at rest and then with engine running

As a Solution, W hat you need is a solid sate regulator or an ignition +ve source that connects to a regulated output
 
Pepsi said:
This sounds suspiciously like you might be onto something.
The USB lead from the tablet is plugged into a cable with an inline fuse which in turn is then connected to the battery, is that what you mean in your first question? I thought these cables automatically reduced the voltage to accessories.

Your comment regarding the USB port shutting down at 14+ volts sounds very feasible, so do you have any suggestions as to how I can resolve this?
Click to expand...
a USB lead is just a direct connection from output to input

you need to buy the correct automotive charger for your tablet - a device that takes the fluctuating voltage from the bike's power system and regulates it to the correct voltage and current. For many devices, they just look like a cigar lighter plug with a bit of extra girth for the circuitry.

I see you have posted as I am typing. That cable is not suitable. You will be whacking whatever is coming out of the alternator at your device. that voltage will fluctuate and be full of nasty spikes.

You need something like this that plugs into the bike's accessory socket (that's a BMW Hella type)

If you do not have an accessory socket on the Husky then get this which goes direct to the battery and does not use any power when not in use https://www.sportsbikeshop.co.uk/motorcycle_parts/content_prod/736802
 
Wessie, I stand corrected, this is the one I have on the bike.

IMG_1238.jpeg
 
that 3M device is the one I linked to at Sportsbike shop with Oxford branding.

As suggested above, you need (or get someone) to check the voltages with a multimeter at the various points, with and without the engine running, to work out what is happening.
 
wessie said:
that 3M device is the one I linked to at Sportsbike shop with Oxford branding.

As suggested above, you need (or get someone) to check the voltages with a multimeter at the various points, with and without the engine running, to work out what is happening.
Click to expand...
Will do, I'll get on it on Monday. Thanks for your help. 👍
 
An update, but the outcome is success.
I bought a few items off Amazon, the installation won't win any awards for professionalism but it all works. I glued the male connector into the female connector and also glued the
cable into the USB A Port. All the cabling is secured & hidden away under the tank & the seat & I managed to tuck the male & female connectors (once glued together) behind the headlight shroud because there is absolutely no room under the seat on an enduro bike! Thank goodness for Gorilla Glue, no way is any of this going to vibrate loose on the trails now.
So it seems that it was simply a matter of too many volts hitting the Samsung Device once the bike was moving, but on tickover it still managed to charge.

Thank you to all who contributed towards helping me identify the problem.



Screenshot 2024-04-27 at 16.52.43.pngScreenshot 2024-04-27 at 16.53.24.pngScreenshot 2024-04-27 at 16.53.54.png
 
You’re lucky not to have a melted tablet - these things are truly idiot proof these days!
 
Nippy Normans supply Touratech, Wunderlich, Desert Fox and many other makes of accessories.
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