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25-03-2023, 08:16 PM
Posts: 163
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The matek r24 receiver has a voltage input (up to 34V) on the 7th set of pins. It's reported back in telemetry as RxBt.
I use it to report the total pack voltage via the balance plug in my batteries. You could do it for a single cell in the pack as well
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Are SBUS servos very common? I've never seen one in the wild.
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Yes, that's the same receiver I use.
It's a common ground with the battery so you only need a single wire to the sense pin. I use a jst-xh terminal to connect to the battery balance connector.
I bought a pack of 10 jst connector pairs (male and female) with wires already soldered on, for $0.02 shipped to my house from AliExpress 😆 (plus $0.28 GST, so $0.30 all up)
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On the matek receivers, what would normally be in the signal position (white) on pin set 7 is the sense pin. (I soldered a red pin into that position on mine)
For total pack voltage sensing, that should be connected to the red wire on the balance plug.
The red and black of pin set 7 on the matek receiver do not need to be connected to anything.
On your balance connector, the black is ground, the red is total pack voltage. The other 2 tap into the connection between each cell in the pack.
You could monitor just the voltage of the lowest cell by using the first wire next to the black, or the total pack voltage by using the red.
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And don't connect the red balance wire to the centre pin, it will put the full pack voltage into everthing on the 5V line, potentially breaking things like servos and speed controllers
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Great news! Good to hear that it worked as expected.
Posts: 163
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Posts: 163
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Joined: Feb 2023