Kindle HD8 FKB AT help w charging and battery consumption

Hi all! Appreciate any assistance in advance…

I’ve been tweaking settings on my wall display for a few weeks now and can’t seem to get it where I want it.

I’ve got a paid version of FKB w the following settings:

  • keep screen on = yes
  • visual motion detection = yes
  • acoustic motion detection = yes
  • turn screen on on motion = yes
  • exit screensaver on motion = yes
  • screensaver timer = 30
  • Screensaver brightness = 0

My default display is an ActionTiles page. AutomateIt and Ring interrupt the default page for 1minute or so occasionally.

On the HD8:

  • Alexa handsfree = off
  • Bluetooth = off
  • default display brightness = ~75%
  • charging is provided by a 2A 5V wall charger (run from basement up to 1st floor on old low voltage wiring (from old security touchpad).

I was expecting, with this setup, to be at or near 100% charged most of the time. I’m more often 30% or below (with occasional device shutdown due to low battery).

Any obvious things I’m missing??!

I have a smaller Kindle with a similar setup although only running ActionToles in FKB. However, my low voltage wiring is only around 1m in length.

It is always 100% charged.

I suspect there will be a lot of voltage drop if your LV cable is long so maybe that is the cause.


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Thanks Ian! The LV cable shows 5V (slightly higher) at the mounting point (with no load, just multimeter probes). Is there a better way to test that theory? Or a preferred method for carrying the voltage across LV cables? Is it better to push 12V and then step down to 5V at the mounting point? Thanks again!

Devices that expect a charge from USB can be fussy. I think the best solution is to have the transformer local to the tablet and step down from 110/240 to 5v using the correct power supply.

I’m using a tablet mount and transformer from here…

(No connection to them other than being a customer).

Might just be the charger. 2A 5V is plenty to keep it fully charged even in heavy use. What gauge is the wire? Typically security wire is 22 gauge but 18 gauge would be more suitable for longer runs. You could have a pinched wire cutting off current flow…

I mount my tablets right above a wall switch and grab power from it and use the standard charger that comes with the Fire HDs.

Thanks rontalley! I spliced the 4 wires into 2 pairs and that gage (whatever it is) seems to be working perfectly!

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