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-   -   real battery voltage through telemetry (https://www.rctech.net/forum/radio-electronics/1124068-real-battery-voltage-through-telemetry.html)

dieandgo 05-24-2024 11:55 PM

real battery voltage through telemetry
 
I am using sanwa electronics and allways see on telemetry 6.0 volts.
I wonder if there is any way to see the real battery voltage at the transmitter because car stops without battery and sanwa is saying 6.0 - 5.9 volts yet. :)

gigaplex 05-25-2024 01:46 AM


Originally Posted by dieandgo (Post 16102568)
I am using sanwa electronics and allways see on telemetry 6.0 volts.
I wonder if there is any way to see the real battery voltage at the transmitter because car stops without battery and sanwa is saying 6.0 - 5.9 volts yet. :)

Which radio and receiver specifically? You probably won't be able to do it without an external voltage sensor.

DirkW 05-25-2024 03:16 AM


Originally Posted by dieandgo (Post 16102568)
I am using sanwa electronics and allways see on telemetry 6.0 volts.
I wonder if there is any way to see the real battery voltage at the transmitter because car stops without battery and sanwa is saying 6.0 - 5.9 volts yet. :)

What you see is the BEC voltage. More useful for nitro drivers, not quite so much for electric. Unless you have special electronics, it's all your receiver can see.

dieandgo 05-25-2024 09:43 AM


Originally Posted by gigaplex (Post 16102570)
Which radio and receiver specifically? You probably won't be able to do it without an external voltage sensor.

with Sanwa M12 and MT4 and 461 receiver. is there any external voltage sensor to connect with this kind of receivers?

riceball777 05-25-2024 10:22 AM

I love this feature on my futaba 10px. I can see everything that my esc sees. I can see the battery voltage so I know how much charger % and run time is left on the car as well as receiver voltage, motor temp, motor rpm, esc temp so much more.

I do t know about sanwa but for my futaba 10px they make a small $30 adapter that one end plugs into my hobbywing esu and the other end plugs into the futaba receiver so I can see all the esc info on the radio

if you look at my picture I sent the larger center gauge to by the cars battery voltage.

https://cimg8.ibsrv.net/gimg/www.rct...4acb5e070.jpeg

rhodopsine 05-25-2024 10:24 AM

One way to have it, if your receiver and servo supports the battery voltage is to solder a servo cable's red and black wires to the positive and negative of your battery connector. then, disconnect the red wire (+) from your ESC wire. This way, your receiver will run out of the battery and what you'll have is the main battery voltage and not the BEC voltage. Of course, like I said, your receiver and servo must support the battery voltage so anything outside of 1s or 2s is bound not to work and may fry your receiver and servo.

Martin Paradis

DirkW 05-25-2024 10:55 AM


Originally Posted by rhodopsine (Post 16102648)
One way to have it, if your receiver and servo supports the battery voltage is to solder a servo cable's red and black wires to the positive and negative of your battery connector. then, disconnect the red wire (+) from your ESC wire. This way, your receiver will run out of the battery and what you'll have is the main battery voltage and not the BEC voltage. Of course, like I said, your receiver and servo must support the battery voltage so anything outside of 1s or 2s is bound not to work and may fry your receiver and servo.

Martin Paradis

Plus, unlike with a BEC your servo will not have constant voltage and therefore get slower with decreasing battery voltage so your car will not handle consistently over the run.

rhodopsine 05-25-2024 11:59 AM


Originally Posted by DirkW (Post 16102655)
Plus, unlike with a BEC your servo will not have constant voltage and therefore get slower with decreasing battery voltage so your car will not handle consistently over the run.

Didn’t think of that but that’s true.

Roelof 05-25-2024 12:39 PM


Originally Posted by DirkW (Post 16102655)
Plus, unlike with a BEC your servo will not have constant voltage and therefore get slower with decreasing battery voltage so your car will not handle consistently over the run.

Then you have to route the red wire of the servo to the red wire of the BEC/ESC.

dieandgo 05-25-2024 02:23 PM


Originally Posted by riceball777 (Post 16102647)
I love this feature on my futaba 10px. I can see everything that my ecu sees. I can see the battery voltage so I know how much charger % and run time is left on the car as well as receiver voltage, motor temp, motor rpm, esc temp so much more.

I do t know about sanwa but for my futaba 10px they make a small $30 adapter that one end plugs into my hobbywing esu and the other end plugs into the futaba receiver so I can see all the esc info on the radio

if you look at my picture I sent the larger center gauge to by the cars battery voltage.

Nice telemetry, really useful!

dieandgo 05-25-2024 02:28 PM


Originally Posted by Roelof (Post 16102670)
Then you have to route the red wire of the servo to the red wire of the BEC/ESC.

Then, make a bypass at receiver red cable from BEC directly to servo, and powering receiver directly from battery would work with any servo?

i see sanwa receivers nominal input voltaje is 4.8 to 7.4v, it will be a problem.

gigaplex 05-25-2024 03:27 PM


Originally Posted by dieandgo (Post 16102680)
Then, make a bypass at receiver red cable from BEC directly to servo, and powering receiver directly from battery would work with any servo?

i see sanwa receivers nominal input voltaje is 4.8 to 7.4v, it will be a problem.

A LiPo nominal voltage is 7.4V. It'll work fine. Nitro users regularly plug a LiPo directly into the receiver.

rhodopsine 05-26-2024 12:02 PM


Originally Posted by dieandgo (Post 16102680)
Then, make a bypass at receiver red cable from BEC directly to servo, and powering receiver directly from battery would work with any servo?

Yes, you could do that. A bit too much work for me if you ask, but then if battery voltage is a useful information for you, then it may be worth it.

Martin Paradis


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