Pocketable Fuel Gauges: pictures and howto [serious]

It never occurred to me to look for a 2 wire/4 digit/42+ volt capable display.
My alternative was to use a 3 wire version with a resistor to drop supply voltage for the input.

It’s not a 2 wire. It’s a 3 wire, 4 digit 100V one

With a ZXTR2005K-13 to power it buried in the epoxy

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Anyway we could soruce a Digital Monitor that shows the Amps passing through?

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Shows voltage, amps going through, how much watts it takes and how many Wh have been charged (number is saved but can be reset)

Can be plugged into your charger only to see its voltage or be connected between charger and battery, it then switches to your boards battery voltage so you see how full it is.

100v and 20a is my version

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Thanks, Brian. I made a few of these and take one on every ride.

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Oohhh…ordering a couple for testing. Thanks for posting!

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Best hack ever!

Is that a voltage-only bypass hack?

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My newest favorite parts are this gauge:

using this for power

https://www.digikey.com/en/products/detail/diodes-incorporated/ZXTR2005K-13/4279448

or the ZXTR2005K from AliExpress (which costs more in the US, and is ten pieces)

add some West System 650 epoxy and these:

male
https://www.mouser.com/ProductDetail/490-PP3-002AH/

female (REQUIRES an epoxy mount solution)
https://www.mouser.com/ProductDetail/490-PR-2155/

and a tiny bit of fishpaper and you can make some shiz looking like this

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So tiny! Why the need for the voltage regulator?

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You can test 4V - 30V and run the gauge from the test wire, but if you exceed 30V you need a separate power source. So I use that part to make 5V from the test voltage. In that configuration, with the ZXTR2005K powering the gauge, it will test 10V - 100V.

Those are also the same gauges I epoxy in the enclosures now, with the same setup, except on the ESC side of the loopkey.

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Not sure what you mean?

I was wondering what the two circled wires were for as they appear to bypass the circuit board, connecting the input directly to the output.

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they are just input and output going in different directions.

this is how it looked with the original connector


e: yep as it seems to are connected to each other.

output←→ input | input ←→ output

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That makes much more sense

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Ahhh…okay, thanks!

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I always share Kevins video, he explains it the best

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My fuel gauge imbeded in deck :slight_smile:
Power button turnes on vesc.

Google Photos

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