Battery voltage sensor for ELRS receiver

[AviateCrate]

Does anyone know a good way to wire up a battery voltage sensor? I have a new ELRS receiver that comes with a sensor wire. I built a short extension with XT30 connectors on each side and soldered the sensor wire to the positive side.

This is connected between the battery and the ESC. It works, but it seems heavier than it needs to be. (Please excuse the lousy soldering, and I did apply the heat shrink before connecting a real battery.)

My other thought was to solder the sensor wire directly to the ESC, but I’m not sure my soldering skills are up to it. If I do that, then the sensor wire must stay with the ESC, so I can’t move it with the receiver to a different plane.

Or, I could connect to the battery balance plug. That would be more flexible, but it requires connecting two cables every time I change a battery.

Any other suggestions? Thanks!

 

[bisco]

I use these on the balance plug, wouldn't know any other way

 

[Foamforce]

I like soldering the sensor lead to the ESC. It‘s a big fat solder pad, you can do it. The only thing I don’t like an out that is that you have to slit the shrink wrap on the ESC to access it. Alternatively, I’ve soldered the lead onto the end of the battery lead on the ESC. That’s a tiny bit less optimal, because then the sensor lead is an extra thing coming into your battery bay, so it’s a little more cluttered, but really not bad. Your option is pretty good too, although you could lighten it by soldering the two xt-30 connectors directly to each other. For strength, you can lay a short length of stripped 14ga wire across the two leads before soldering. Just direct the cupped area up on both sides, lay the wire in there, and fill it up.

 

[AviateCrate]

Thanks! I’ll try soldering to the battery end of the ESC leads. The pads on my 18A ESC are fairly small, but maybe I’ll try it with a bigger one later.

I suppose the “audio telemetry” with the battery alarms on the balance lead would work too. I’ve gotten really spoiled being able to see the battery voltage on my radio. No more timers!

Thanks again!