Hi Mirangi, thank you so much for the two links.
Unfortunately, the first one doesn't open. Here's the screen I get.
However, I went to the Texas Instruments website and searched for the LM136. The cost is absurd, about $14 each.
Electronic components, which can be found for 2 euros in sets of 50.
For now, I've ordered the TL 431 and already have the Zeners.
As for the second link, it's very interesting and useful, and I thank you for showing it to me.
[{"id":"17784318642","url":"https:\/\/model-boats.com\/media\/17784318642\/l","thumbUrl":"https:\/\/model-boats.com\/media\/17784318642\/s","name":"17784318642","caption":""}]
Unfortunately, the first one doesn't open. Here's the screen I get.
However, I went to the Texas Instruments website and searched for the LM136. The cost is absurd, about $14 each.
Electronic components, which can be found for 2 euros in sets of 50.
For now, I've ordered the TL 431 and already have the Zeners.
As for the second link, it's very interesting and useful, and I thank you for showing it to me.
Hi
Digikey. Italy
https://www.digikey.it/it/products/detail/texas-instruments/LM136AH-2-5/+5055949+
Found this
https://320volt.com/en/6v-battery-discharge-protection-circuit/
Good luck
Steve
Thanks again, Mirangi. I'm mainly looking for the component you mentioned, the LM136, because I prefer to follow your instructions, but the problem is I can't find it on Aliexpress either.
I'm sorry to say this, but for a few years now, stores (here in Rome) no longer stock electronic components; they order them as needed. Now I order them myself, so I've been sourcing electronic components on Aliexpress for a few years.
I usually find everything (even relays for my boiler board, which I saved 150 euros for), but LM136.
Maybe I'm a bit daft. If you have a link to a successful search, could you send it to me?
Thanks again, Mirangi. I'm mainly looking for the component you mentioned, the LM136, because I prefer to follow your instructions, but the problem is I can't find it on Aliexpress either.
I'm sorry to say this, but for a few years now, stores (here in Rome) no longer stock electronic components; they order them as needed. Now I order them myself, so I've been sourcing electronic components on Aliexpress for a few years.
I usually find everything (even relays for my boiler board, which I saved 150 euros for), but LM136.
Maybe I'm a bit daft. If you have a link to a successful search, could you send it to me?
Hi,
Happy to help. The inputs are centered around 2.5 volts, the LM136 is correct. You could use a zener but the LM136 is much easier and stable.
The LM136 is also a 3 leg device but you don’t need to use the trim facility for our usage. The TL431 could be used but more complicated.
You could use a standard zener to test the circuit.
Hi Mirangi.
Thanks again for this new information, always much appreciated.
I've come to the conclusion that for the "Francesca" RC naval model (where I have plenty of space available) and for other future projects, I'll adopt the configuration in the first message.
However, I also want to memorize and archive the solution you gave me, because it might come in handy someday.
This LM393-based circuit is actually very inexpensive and worth testing, even just for the fun of it. I hope you do too (if you want, of course).
I asked if the circuit you posted would also work with 6-volt batteries because I had a doubt reading the technical specifications of the LM393 integrated circuit.
The doubt arose from these considerations: it's true that the LM393 accepts supply voltages (Vcc) from 2 to 36 volts, but the inputs must remain at least 1.5 volts (Vicr) below Vcc.
So I thought the battery should be at least 7.5 volts, but your affirmative answer made me think better, and I thought that with the resistors you lowered the input threshold (which should be at least 4.5 volts, i.e., 6 - 1.5 volts) for the comparison on inputs 2 and 3.
The functions of the other components (capacitor, diodes, transistor, other resistors) are clear to me.
I'll take advantage of your expertise for other questions; sorry if they seem trivial.
I don't know when I'll try the circuit, but in the meantime, I'm trying to find the components (given their low cost). Well, I haven't been able to find the LM-136 electronic component on the market.
Can you confirm the nomenclature?
I looked for an alternative and found the TL431, which is available commercially.
Can you tell me if it seems like a suitable replacement to you?
However, if the TL431 works fine, another problem arises: this component has three pins, not two. How do I connect it to the circuit you made? Which pins should I connect and which should I exclude?
Initially, I thought you were referring to a Zener diode, in addition to the symbol, as already mentioned, also because it has two pins.
If I find the solution to the component needed for the Vref, I might eventually test it on a breadboard with a single relay (at low currents). If it works, I can add the second power relay and structure it definitively.
Thanks to you (for now, Mirangi and SimpleSailor, but other ideas are welcome), the topic has become even more interesting for me.
Thanks again for this new information, always much appreciated.
I've come to the conclusion that for the "Francesca" RC naval model (where I have plenty of space available) and for other future projects, I'll adopt the configuration in the first message.
However, I also want to memorize and archive the solution you gave me, because it might come in handy someday.
This LM393-based circuit is actually very inexpensive and worth testing, even just for the fun of it. I hope you do too (if you want, of course).
I asked if the circuit you posted would also work with 6-volt batteries because I had a doubt reading the technical specifications of the LM393 integrated circuit.
The doubt arose from these considerations: it's true that the LM393 accepts supply voltages (Vcc) from 2 to 36 volts, but the inputs must remain at least 1.5 volts (Vicr) below Vcc.
So I thought the battery should be at least 7.5 volts, but your affirmative answer made me think better, and I thought that with the resistors you lowered the input threshold (which should be at least 4.5 volts, i.e., 6 - 1.5 volts) for the comparison on inputs 2 and 3.
The functions of the other components (capacitor, diodes, transistor, other resistors) are clear to me.
I'll take advantage of your expertise for other questions; sorry if they seem trivial.
I don't know when I'll try the circuit, but in the meantime, I'm trying to find the components (given their low cost). Well, I haven't been able to find the LM-136 electronic component on the market.
Can you confirm the nomenclature?
I looked for an alternative and found the TL431, which is available commercially.
Can you tell me if it seems like a suitable replacement to you?
However, if the TL431 works fine, another problem arises: this component has three pins, not two. How do I connect it to the circuit you made? Which pins should I connect and which should I exclude?
Initially, I thought you were referring to a Zener diode, in addition to the symbol, as already mentioned, also because it has two pins.
If I find the solution to the component needed for the Vref, I might eventually test it on a breadboard with a single relay (at low currents). If it works, I can add the second power relay and structure it definitively.
Thanks to you (for now, Mirangi and SimpleSailor, but other ideas are welcome), the topic has become even more interesting for me.
Sorry, system keeps losing my textHad a look at other options, an Arduino project will be overkill and realistically beyond most people of our age,programming, calibrating and even supplying 5 volts from a 6 volt battery are all issues.
Realistically the use of a spare RC channel to switch batteries is probably thr easiest and most reliable way of doing this.
I found a couple of things that might be of use:
1. For small loads (10A ) two micro-switches mounted on servo, operated by a cam coul switch two relays ( like the old days)
2. For higher loads these micro-switches could operate two relays.
3. Using 2 relays means cheap car relays SPST could be used.
4. To use 12 volt relays very cheap “Buck Boost” converters can easily convert 6 volts to 12 volts. These are less than $2 Australian from TEMU or similar
ELECTRIC POWER SYSTEM THAT ALLOWS SWITCHING FROM A MAIN BATTERY TO A SPARE BATTERY, FOR SAFER NAVIGA
Sorry, system keeps losing my textHad a look at other options, an Arduino project will be overkill and realistically beyond most people of our age,programming, calibrating and even supplying 5 volts from a 6 volt battery are all issues.
Realistically the use of a spare RC channel to switch batteries is probably thr easiest and most reliable way of doing this.
I found a couple of things that might be of use:
1. For small loads (10A ) two micro-switches mounted on servo, operated by a cam coul switch two relays ( like the old days)
2. For higher loads these micro-switches could operate two relays.
3. Using 2 relays means cheap car relays SPST could be used.
4. To use 12 volt relays very cheap “Buck Boost” converters can easily convert 6 volts to 12 volts. These are less than $2 Australian from TEMU or similar
Had a look at other options, an Arduino project will be overkill and realistically beyond most people of our age,programming, calibrating and even supplying 5 volts from a 6 volt battery are all issues.
Realistically the use of a spare RC channel to switch batteries is probably thr easiest and most reliable way of doing this.
I found a couple of things that might be of use:
1. For small loads (10A these micro-switches could control two relays.
3. Using 2 relays means cheap car relays SPST could be used.
4. To use 12 volt relays very cheap “Buck Boost” converters can easily convert 6 volts to 12 volts. These are less than $2 Australian from TEMU or similar
Hope this info can be of use for someone.
ELECTRIC POWER SYSTEM THAT ALLOWS SWITCHING FROM A MAIN BATTERY TO A SPARE BATTERY, FOR SAFER NAVIGA
Had a look at other options, an Arduino project will be overkill and realistically beyond most people of our age,programming, calibrating and even supplying 5 volts from a 6 volt battery are all issues.
Realistically the use of a spare RC channel to switch batteries is probably thr easiest and most reliable way of doing this.
I found a couple of things that might be of use:
1. For small loads (10A these micro-switches could control two relays.
3. Using 2 relays means cheap car relays SPST could be used.
4. To use 12 volt relays very cheap “Buck Boost” converters can easily convert 6 volts to 12 volts. These are less than $2 Australian from TEMU or similar
Hi Mirangi, I understand everything. Yes, of course we can manually disconnect the button when the boat returns; correct.
Sorry, that symbol meant Zener diode, but you correctly specified the abbreviation (LM136).
Thank you so much for your contribution.
I don't rule out doing a practical test someday; I'll check the availability of all the components first.
Are you planning to test it?
ELECTRIC POWER SYSTEM THAT ALLOWS SWITCHING FROM A MAIN BATTERY TO A SPARE BATTERY, FOR SAFER NAVIGA
Hi Mirangi, I understand everything. Yes, of course we can manually disconnect the button when the boat returns; correct.
Sorry, that symbol meant Zener diode, but you correctly specified the abbreviation (LM136).
Thank you so much for your contribution.
I don't rule out doing a practical test someday; I'll check the availability of all the components first.
Are you planning to test it?
Hi Alessandro,
Definitely should work on 6 volts. Relay operation is as you describe, Reset is a manual button in the boat, makes no sense to reset by radio as the battery needs charging before it can be used again. Remember the reason for this is to get the boat back if the main battery is exhausted.
LED across coil to indicate switching has occured.
With the relay I would use a small relay one set of contacts latches the relay then use the other contacts to operate the heavy duty relay. This would only need one set of contacts, much easier to find I think. SPDT.
Note that Vref is not a Zener Diode, it’s a special voltage reference device with hi accuracy
ELECTRIC POWER SYSTEM THAT ALLOWS SWITCHING FROM A MAIN BATTERY TO A SPARE BATTERY, FOR SAFER NAVIGA
Hi Alessandro,
Definitely should work on 6 volts. Relay operation is as you describe, Reset is a manual button in the boat, makes no sense to reset by radio as the battery needs charging before it can be used again. Remember the reason for this is to get the boat back if the main battery is exhausted.
LED across coil to indicate switching has occured.
With the relay I would use a small relay one set of contacts latches the relay then use the other contacts to operate the heavy duty relay. This would only need one set of contacts, much easier to find I think. SPDT.
Note that Vref is not a Zener Diode, it’s a special voltage reference device with hi accuracy
Nice one Mirangi. That should work, I like the latching idea and the use of a LM393 comparator. It should cut out any chance of relay chatter.👍As suggested I would use a small PCB mounted relay (RLY1 & 2) to power a larger high current relay for switching the main power.
ELECTRIC POWER SYSTEM THAT ALLOWS SWITCHING FROM A MAIN BATTERY TO A SPARE BATTERY, FOR SAFER NAVIGA
Nice one Mirangi. That should work, I like the latching idea and the use of a LM393 comparator. It should cut out any chance of relay chatter.👍As suggested I would use a small PCB mounted relay (RLY1 & 2) to power a larger high current relay for switching the main power.
Hi Mirangi, that's certainly interesting. The diagram is very clear, thanks (with all the values), excellent.
I took a quick look at the diagram, but I plan to study it more closely later.
Of course, it would have been better if you had tried it (practical tests always reveal something useful and identify any potential problems), but in the meantime, I'd like to ask you a few preliminary questions.
1. Do you think it's also suitable for 6-volt batteries?
2. If I understand correctly, you need to use an 8-pin relay [two for the coil (RLY1), three for the first switch (RLY1.1), and three for the second switch (RL1.2)].
If I understand correctly, the RLY1.1 switch is used for the latching (I hope this term is translated correctly, otherwise it won't make sense) of the relay itself.
To release a latching, you need a button, and in fact, you put it [PB1 _NC].
So the question is this: if I need to remotely reset with the button, I should use a radio control. But if I use a radio control, wouldn't it be quicker to use the manual switching from the first diagram (by the way, can you see it now?)?
3. Would you put the indicator LED in parallel with the relay coil? Or where?
It would be fun to check this diagram anyway.
I have almost all the components; I need to check the LM393, the Zener size, and, among the potentiometers, one with 10 turns.
I need a 6-volt, 8-pin (DPDT) relay that can handle high current, and it's not easy to find cheaply.
ELECTRIC POWER SYSTEM THAT ALLOWS SWITCHING FROM A MAIN BATTERY TO A SPARE BATTERY, FOR SAFER NAVIGA
Hi Mirangi, that's certainly interesting. The diagram is very clear, thanks (with all the values), excellent.
I took a quick look at the diagram, but I plan to study it more closely later.
Of course, it would have been better if you had tried it (practical tests always reveal something useful and identify any potential problems), but in the meantime, I'd like to ask you a few preliminary questions.
1. Do you think it's also suitable for 6-volt batteries?
2. If I understand correctly, you need to use an 8-pin relay [two for the coil (RLY1), three for the first switch (RLY1.1), and three for the second switch (RL1.2)].
If I understand correctly, the RLY1.1 switch is used for the latching (I hope this term is translated correctly, otherwise it won't make sense) of the relay itself.
To release a latching, you need a button, and in fact, you put it [PB1 _NC].
So the question is this: if I need to remotely reset with the button, I should use a radio control. But if I use a radio control, wouldn't it be quicker to use the manual switching from the first diagram (by the way, can you see it now?)?
3. Would you put the indicator LED in parallel with the relay coil? Or where?
It would be fun to check this diagram anyway.
I have almost all the components; I need to check the LM393, the Zener size, and, among the potentiometers, one with 10 turns.
I need a 6-volt, 8-pin (DPDT) relay that can handle high current, and it's not easy to find cheaply.
Hi
I’ve attached a possible solution to the battery change over problem. I haven’t tried this but I expect it will work. Cheap easily obtained parts.
Notes
Vref maintains stable 2.5 volt reference
Ic1 compares the battery voltage to the reference, adjustable trip using 10k potentiometer ( suggest 10 turn type for fine adjustment)
D1 and C1 will hopefully maintain this cuircuit during the relay change over.
I would suggest using a small DPDT relay and use this to drive the heavy duty relay.
Once relay operates it “latches “ until the “Reset “ button (PB1) is pressed.
LEDs / warning siren/ etc can be connected across RLY1 but watch current draw.
Hope this is of interest.
[{"id":"177813871258","url":"https:\/\/model-boats.com\/media\/177813871258\/l","thumbUrl":"https:\/\/model-boats.com\/media\/177813871258\/s","name":"177813871258","caption":""}]
ELECTRIC POWER SYSTEM THAT ALLOWS SWITCHING FROM A MAIN BATTERY TO A SPARE BATTERY, FOR SAFER NAVIGA
Hi
I’ve attached a possible solution to the battery change over problem. I haven’t tried this but I expect it will work. Cheap easily obtained parts.
Notes
Vref maintains stable 2.5 volt reference
Ic1 compares the battery voltage to the reference, adjustable trip using 10k potentiometer ( suggest 10 turn type for fine adjustment)
D1 and C1 will hopefully maintain this cuircuit during the relay change over.
I would suggest using a small DPDT relay and use this to drive the heavy duty relay.
Once relay operates it “latches “ until the “Reset “ button (PB1) is pressed.
LEDs / warning siren/ etc can be connected across RLY1 but watch current draw.
Hi SimpleSailor, yes, I confirm the red cross indicates that the red (positive) wire must be isolated.
Of course, I never recommend cutting the BEC cable directly (nor do I do it), but rather insert an extension cable (with the positive wire cut).
I've attached some explanatory screenshots.
If you have any other questions, let me know.
[{"id":"177806011192","url":"https:\/\/model-boats.com\/media\/177806011192\/l","thumbUrl":"https:\/\/model-boats.com\/media\/177806011192\/s","name":"177806011192","caption":""},{"id":"177806015437","url":"https:\/\/model-boats.com\/media\/177806015437\/l","thumbUrl":"https:\/\/model-boats.com\/media\/177806015437\/s","name":"177806015437","caption":""},{"id":"177806015562","url":"https:\/\/model-boats.com\/media\/177806015562\/l","thumbUrl":"https:\/\/model-boats.com\/media\/177806015562\/s","name":"177806015562","caption":""}]
ELECTRIC POWER SYSTEM THAT ALLOWS SWITCHING FROM A MAIN BATTERY TO A SPARE BATTERY, FOR SAFER NAVIGA
Hi SimpleSailor, yes, I confirm the red cross indicates that the red (positive) wire must be isolated.
Of course, I never recommend cutting the BEC cable directly (nor do I do it), but rather insert an extension cable (with the positive wire cut).
I've attached some explanatory screenshots.
If you have any other questions, let me know.
Hi Alessandro
Just noticed on your schematic. You need to remove the positive feed from the BEC on the ESC which goes to the RX. Only have the power coming from the 6V RX battery. I take it the RL-On-Off is an electronic switch. Keep all the negative wires as you have them. MAYBE that is what the cross on the + wire means.?
ELECTRIC POWER SYSTEM THAT ALLOWS SWITCHING FROM A MAIN BATTERY TO A SPARE BATTERY, FOR SAFER NAVIGA
Hi Alessandro
Just noticed on your schematic. You need to remove the positive feed from the BEC on the ESC which goes to the RX. Only have the power coming from the 6V RX battery. I take it the RL-On-Off is an electronic switch. Keep all the negative wires as you have them. MAYBE that is what the cross on the + wire means.?
Hi Mirangi, I'd be very happy and interested to see your solution (Arduino solution) regarding automatic switching, just as I'm interested in SimpleSailor's.
Another option would be to use PNP transistors and MOSFETs (I probably shouldn't even buy them because I have several types), but I'm having problems with the threshold and managing 6-volt batteries, as well as high current issues (but a mixed transistor-relay system could solve this). In short, everything gets a bit complicated, and any previous knowledge disappears. Furthermore, the type of battery used must be carefully considered.
The first scheme, on the other hand (super cheap), is suitable for any type of battery technology in use.
P.S. I'm attaching the first scheme, which, at least I think, is the best solution.
This solution is also compatible with a radio control/receiver capable of reading the battery's charge status and voltage.
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ELECTRIC POWER SYSTEM THAT ALLOWS SWITCHING FROM A MAIN BATTERY TO A SPARE BATTERY, FOR SAFER NAVIGA
Hi Mirangi, I'd be very happy and interested to see your solution (Arduino solution) regarding automatic switching, just as I'm interested in SimpleSailor's.
Another option would be to use PNP transistors and MOSFETs (I probably shouldn't even buy them because I have several types), but I'm having problems with the threshold and managing 6-volt batteries, as well as high current issues (but a mixed transistor-relay system could solve this). In short, everything gets a bit complicated, and any previous knowledge disappears. Furthermore, the type of battery used must be carefully considered.
The first scheme, on the other hand (super cheap), is suitable for any type of battery technology in use.
P.S. I'm attaching the first scheme, which, at least I think, is the best solution.
This solution is also compatible with a radio control/receiver capable of reading the battery's charge status and voltage.
Hi,
For some reason I did not see the original drawing. This design occurred to me as well though I initially discounted it, I now see that this is the best solution without electronics getting involved.
I have designed a voltage monitoring /switching circuit but have a problem monitoring the battery voltage and using the same battery to power it. Could overcome this but the original design is simpler.
Monitoring /Auto switching would be an easy Arduino project you could have all kinds of bells and whistles. Might look at this when I have time.
ELECTRIC POWER SYSTEM THAT ALLOWS SWITCHING FROM A MAIN BATTERY TO A SPARE BATTERY, FOR SAFER NAVIGA
Hi,
For some reason I did not see the original drawing. This design occurred to me as well though I initially discounted it, I now see that this is the best solution without electronics getting involved.
I have designed a voltage monitoring /switching circuit but have a problem monitoring the battery voltage and using the same battery to power it. Could overcome this but the original design is simpler.
Monitoring /Auto switching would be an easy Arduino project you could have all kinds of bells and whistles. Might look at this when I have time.
Hi Mirangi, thanks for your opinion.
The automatic switching solution does indeed pose several problems and needs to be refined further, that's for sure.
I'm aware of the possibility of using more sophisticated radios to read the voltage or battery charge, but what I've proposed is a low-cost, DIY solution with just a few components (of course, it's quicker and safer to buy ready-made devices).
Another solution could be Arduino.
The self-latching relay is an interesting idea; I'll have to think about it, but if you already have a design in mind, please show it.
But let's say the discussion has gotten a bit broader, and we've digressed a bit, just for fun and for the fun of it.
Actually, I think we can all agree that the solution in the first message is the easiest and most effective for the intended purpose.
What do you think? Have you seen the schematic for the first message? Are you convinced, or do you notice any issues?
P.S. There's no doubt that the receiver must be powered separately.
The diagram in the first message clearly shows the direct connection to the battery, while the BEC positive is isolated.
In the automatic switching diagram, I didn't draw the connections to the receiver to avoid complicating the drawing, but I assumed that the receiver (and consequently all the loads connected to it) are powered separately.
As a rule, I always prefer to separate the power supplies and almost never use the BEC.
ELECTRIC POWER SYSTEM THAT ALLOWS SWITCHING FROM A MAIN BATTERY TO A SPARE BATTERY, FOR SAFER NAVIGA
Hi Mirangi, thanks for your opinion.
The automatic switching solution does indeed pose several problems and needs to be refined further, that's for sure.
I'm aware of the possibility of using more sophisticated radios to read the voltage or battery charge, but what I've proposed is a low-cost, DIY solution with just a few components (of course, it's quicker and safer to buy ready-made devices).
Another solution could be Arduino.
The self-latching relay is an interesting idea; I'll have to think about it, but if you already have a design in mind, please show it.
But let's say the discussion has gotten a bit broader, and we've digressed a bit, just for fun and for the fun of it.
Actually, I think we can all agree that the solution in the first message is the easiest and most effective for the intended purpose.
What do you think? Have you seen the schematic for the first message? Are you convinced, or do you notice any issues?
P.S. There's no doubt that the receiver must be powered separately.
The diagram in the first message clearly shows the direct connection to the battery, while the BEC positive is isolated.
In the automatic switching diagram, I didn't draw the connections to the receiver to avoid complicating the drawing, but I assumed that the receiver (and consequently all the loads connected to it) are powered separately.
As a rule, I always prefer to separate the power supplies and almost never use the BEC.
Just realised another issue with the current design. During the relay change over the drop in voltage might trip the ESC or Rx.
System needs to connect the backup battery before disconnecting the main battery or provide power during the changeover (perhaps a large capacitor)
Lots of info on the internet.
Steve
Interesting subject, I can see why you would like a system to automatically change over the batteries when the main one gets close to the ESC drop out voltage.
I can however see a few issues with the simple systems proposed.
1. I think the relay could be wired in such a way that it “latches” when it changes over to the backup battery. This would prevent relay chatter.
2. The proposed system won’t work reliably as there is no way of setting a clear and accurate switching point. The relay drop out voltage would occur at different levels depending on motor load. I believe the ESC or RX will probably drop out before the relay.
3. Having been negative to this point, I now say that I think there is probably a simple solution for this, using a small electronic circuit to monitor the main battery voltage then change over to the backup battery. The circuit could just signal that the main battery is getting low and it’s time to bring the boat in.
I’m sure there are greater minds than mine on this site but I will see what I can figure out.
ELECTRIC POWER SYSTEM THAT ALLOWS SWITCHING FROM A MAIN BATTERY TO A SPARE BATTERY, FOR SAFER NAVIGA
Interesting subject, I can see why you would like a system to automatically change over the batteries when the main one gets close to the ESC drop out voltage.
I can however see a few issues with the simple systems proposed.
1. I think the relay could be wired in such a way that it “latches” when it changes over to the backup battery. This would prevent relay chatter.
2. The proposed system won’t work reliably as there is no way of setting a clear and accurate switching point. The relay drop out voltage would occur at different levels depending on motor load. I believe the ESC or RX will probably drop out before the relay.
3. Having been negative to this point, I now say that I think there is probably a simple solution for this, using a small electronic circuit to monitor the main battery voltage then change over to the backup battery. The circuit could just signal that the main battery is getting low and it’s time to bring the boat in.
I’m sure there are greater minds than mine on this site but I will see what I can figure out.
Thanks for your feedback, SimpleSailor.
I agree with you on everything.
Above all, I agree that remote-controlled switching like the one in the first post in this topic remains the best solution.
Regarding automatic switching,
an electronic voltage management circuit to properly control the relay is certainly necessary for proper operation.
I'd be very happy to see the circuit you have in mind, obviously when you have time and without obligation.
Just for fun, I thought about creating a voltage drop (calculated initially but then calibrated with practical tests) on the coil's electrical branch to be sure (or almost) that the ESC doesn't shut down before the coil shuts down.
Furthermore, a lower shutdown threshold (created with small voltage drops) could eliminate the main battery from being activated when it recharges after a period of non-use. The system is certainly very empirical.
ELECTRIC POWER SYSTEM THAT ALLOWS SWITCHING FROM A MAIN BATTERY TO A SPARE BATTERY, FOR SAFER NAVIGA
Thanks for your feedback, SimpleSailor.
I agree with you on everything.
Above all, I agree that remote-controlled switching like the one in the first post in this topic remains the best solution.
Regarding automatic switching,
an electronic voltage management circuit to properly control the relay is certainly necessary for proper operation.
I'd be very happy to see the circuit you have in mind, obviously when you have time and without obligation.
Just for fun, I thought about creating a voltage drop (calculated initially but then calibrated with practical tests) on the coil's electrical branch to be sure (or almost) that the ESC doesn't shut down before the coil shuts down.
Furthermore, a lower shutdown threshold (created with small voltage drops) could eliminate the main battery from being activated when it recharges after a period of non-use. The system is certainly very empirical.
Hi Alessandro.
If you try the system shown in both diagrams you might get some relay chatter. When the first battery gets too low in voltage to remain energised it will drop out and switch to the second battery. However when the first battery recovers a little it could then (energise) pull the relay back in again, and so the cycle continues and you get relay chatter which may damage the ESC. I would stick to the manual system. If you do it automatically you need some electronics to create a voltage window with a high and low limit for the cut in cut out of the relay. This is the hysteresis I mentioned in the last comment. If I get a chance I will look out a circuit, but for now I am very busy with the renovation of our bungalow. 😀
ELECTRIC POWER SYSTEM THAT ALLOWS SWITCHING FROM A MAIN BATTERY TO A SPARE BATTERY, FOR SAFER NAVIGA
Hi Alessandro.
If you try the system shown in both diagrams you might get some relay chatter. When the first battery gets too low in voltage to remain energised it will drop out and switch to the second battery. However when the first battery recovers a little it could then (energise) pull the relay back in again, and so the cycle continues and you get relay chatter which may damage the ESC. I would stick to the manual system. If you do it automatically you need some electronics to create a voltage window with a high and low limit for the cut in cut out of the relay. This is the hysteresis I mentioned in the last comment. If I get a chance I will look out a circuit, but for now I am very busy with the renovation of our bungalow. 😀
I tried adding a signal diode to the previous diagram, but I haven't succeeded yet.
The only solution I've found is to use an 8-pin relay, with double switches.
I'll leave the diagram undescribed for now; I hope it's easy to understand.
When the backup battery kicks in, the LED lights up.
Of course, you could also connect buzzers or a small radio transmitter in parallel with the LED.
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ELECTRIC POWER SYSTEM THAT ALLOWS SWITCHING FROM A MAIN BATTERY TO A SPARE BATTERY, FOR SAFER NAVIGA
I tried adding a signal diode to the previous diagram, but I haven't succeeded yet.
The only solution I've found is to use an 8-pin relay, with double switches.
I'll leave the diagram undescribed for now; I hope it's easy to understand.
When the backup battery kicks in, the LED lights up.
Of course, you could also connect buzzers or a small radio transmitter in parallel with the LED.
Automatic battery switching.
This is a possible solution for automatic battery switching.
I'm only showing it because I mentioned it in previous posts, but I'm sure the best solution is the one in the first post.
As I said, if you don't notice the switching, it's of little or no use.
I haven't tried it (I tested and made a video of another solution, but I can't find it anymore), but I think this could work too.
The diagram is simple.
A battery (the main one on the right in the diagram) is connected to the coil of a five-pin relay with positive and negative poles.
The relay is 6 volts with five contacts: two for the coil, a common contact, a normally open contact, and a normally closed contact (I can't find the 40 amp automotive ones cheaply; I can find plenty of 12 volt and 24 volt ones, but unfortunately no 6 volt ones).
The main battery has, in parallel, another load represented by the ESC and the motor.
The positive pole of the main battery is connected to the normally open contact of the relay.
The common contact of the relay is connected to the positive pole of the ESC.
The negative pole of the main battery is connected (along with that of the backup battery) to the negative pole of the ESC.
Finally, the positive pole of the backup battery is connected to the normally closed contact.
I avoided showing the receiver for ease of understanding (I can include it if you like).
The system should work like this:
The first battery powers both the relay coil and the motor via the ESC. The normally open contact is closed because the coil is energized, changing its initial state of rest.
When the battery is discharged, the coil is no longer energized and the contacts switch.
The normally open contact opens, the normally closed contact closes, and therefore power is automatically switched from the main battery to the backup.
There are three problems:
1. I don't know if continuously energizing the coil can damage it. I don't think so, but I'll have to test it.
2. During normal operation, the coil's current draw must be added to the ESC/motor's current draw.
3. It's important to prevent a low battery from causing the ESC/motor to shut down before the coil de-energizes, for obvious reasons.
How would you solve the third problem?
Please tell me if I've made any mistakes (I usually discover them after practical testing).
[{"id":"177792422684","url":"https:\/\/model-boats.com\/media\/177792422684\/l","thumbUrl":"https:\/\/model-boats.com\/media\/177792422684\/s","name":"177792422684","caption":""}]
ELECTRIC POWER SYSTEM THAT ALLOWS SWITCHING FROM A MAIN BATTERY TO A SPARE BATTERY, FOR SAFER NAVIGA
Automatic battery switching.
This is a possible solution for automatic battery switching.
I'm only showing it because I mentioned it in previous posts, but I'm sure the best solution is the one in the first post.
As I said, if you don't notice the switching, it's of little or no use.
I haven't tried it (I tested and made a video of another solution, but I can't find it anymore), but I think this could work too.
The diagram is simple.
A battery (the main one on the right in the diagram) is connected to the coil of a five-pin relay with positive and negative poles.
The relay is 6 volts with five contacts: two for the coil, a common contact, a normally open contact, and a normally closed contact (I can't find the 40 amp automotive ones cheaply; I can find plenty of 12 volt and 24 volt ones, but unfortunately no 6 volt ones).
The main battery has, in parallel, another load represented by the ESC and the motor.
The positive pole of the main battery is connected to the normally open contact of the relay.
The common contact of the relay is connected to the positive pole of the ESC.
The negative pole of the main battery is connected (along with that of the backup battery) to the negative pole of the ESC.
Finally, the positive pole of the backup battery is connected to the normally closed contact.
I avoided showing the receiver for ease of understanding (I can include it if you like).
The system should work like this:
The first battery powers both the relay coil and the motor via the ESC. The normally open contact is closed because the coil is energized, changing its initial state of rest.
When the battery is discharged, the coil is no longer energized and the contacts switch.
The normally open contact opens, the normally closed contact closes, and therefore power is automatically switched from the main battery to the backup.
There are three problems:
1. I don't know if continuously energizing the coil can damage it. I don't think so, but I'll have to test it.
2. During normal operation, the coil's current draw must be added to the ESC/motor's current draw.
3. It's important to prevent a low battery from causing the ESC/motor to shut down before the coil de-energizes, for obvious reasons.
How would you solve the third problem?
Please tell me if I've made any mistakes (I usually discover them after practical testing).
Hi SimpleSailor, thanks for your authoritative and appreciated opinion.
Your approval gives me great reassurance.
As I mentioned, I had created another scheme for automatic switching, but it didn't meet my needs or those of many other modelers.
If you test the model in a pool or a small pond, this system is certainly superfluous, but in very large lakes, it's very useful.
I pushed the model ship quite far from the shore, and running out of battery power when it's far away can mean losing the model, especially if there's wind that pushes it even further away.
You can organize yourself with other model ships or a dinghy (if you don't want to swim), but I think a reserve battery is the best solution.
ELECTRIC POWER SYSTEM THAT ALLOWS SWITCHING FROM A MAIN BATTERY TO A SPARE BATTERY, FOR SAFER NAVIGA
Hi SimpleSailor, thanks for your authoritative and appreciated opinion.
Your approval gives me great reassurance.
As I mentioned, I had created another scheme for automatic switching, but it didn't meet my needs or those of many other modelers.
If you test the model in a pool or a small pond, this system is certainly superfluous, but in very large lakes, it's very useful.
I pushed the model ship quite far from the shore, and running out of battery power when it's far away can mean losing the model, especially if there's wind that pushes it even further away.
You can organize yourself with other model ships or a dinghy (if you don't want to swim), but I think a reserve battery is the best solution.
Hi Brian (Muddy), thanks so much for your appreciation. As I said, I used the batteries I had, but everyone can choose their favorites.
You're right, LiPos are the best in terms of electrical charge, lightness, and other performance. I'm still using AGM lead-acid batteries because they're the cheapest.
Furthermore, if I design the model for the worst-case scenario (in terms of size and especially weight), I can always change battery type without any problems.
Finally, I'm still a little wary of LiPo batteries, but that's my flaw.
Before testing this scheme, I tried some ESCs from Aliexpress. One was shorted, but I didn't know it. In my haste, I didn't put a fuse between the ESC and the battery.
When the ESC started smoking, I pulled the cable and burned my fingers because the insulation had melted.
I thought I'd damaged the battery as well, but it remained intact.
I think a LiPo would have been worse.
P.S. I started looking at your Harbour, unfortunately I had always overlooked it until now, I like it a lot.
ELECTRIC POWER SYSTEM THAT ALLOWS SWITCHING FROM A MAIN BATTERY TO A SPARE BATTERY, FOR SAFER NAVIGA
Hi Brian (Muddy), thanks so much for your appreciation. As I said, I used the batteries I had, but everyone can choose their favorites.
You're right, LiPos are the best in terms of electrical charge, lightness, and other performance. I'm still using AGM lead-acid batteries because they're the cheapest.
Furthermore, if I design the model for the worst-case scenario (in terms of size and especially weight), I can always change battery type without any problems.
Finally, I'm still a little wary of LiPo batteries, but that's my flaw.
Before testing this scheme, I tried some ESCs from Aliexpress. One was shorted, but I didn't know it. In my haste, I didn't put a fuse between the ESC and the battery.
When the ESC started smoking, I pulled the cable and burned my fingers because the insulation had melted.
I thought I'd damaged the battery as well, but it remained intact.
I think a LiPo would have been worse.
P.S. I started looking at your Harbour, unfortunately I had always overlooked it until now, I like it a lot.
Hi Dave, you're right, the actual test is quite a tangle of cables.
Actually, when I do practical tests, I don't care about aesthetics.
Furthermore, I often take existing cables and don't cut them to the right length to avoid wasting them, so the test shows very long cables, making it even more difficult to see.
Of course, if you decide to implement this power supply system, all the cables will be cut to the minimum length needed to maintain a tidy, clean wiring and reduce weight.
Even better would be to create a small board on which to make the connections and solder them, thus further reducing the number of cables.
In any case, by following the diagram, everyone can optimize their own wiring and adapt it to their own ship model.
ELECTRIC POWER SYSTEM THAT ALLOWS SWITCHING FROM A MAIN BATTERY TO A SPARE BATTERY, FOR SAFER NAVIGA
Hi Dave, you're right, the actual test is quite a tangle of cables.
Actually, when I do practical tests, I don't care about aesthetics.
Furthermore, I often take existing cables and don't cut them to the right length to avoid wasting them, so the test shows very long cables, making it even more difficult to see.
Of course, if you decide to implement this power supply system, all the cables will be cut to the minimum length needed to maintain a tidy, clean wiring and reduce weight.
Even better would be to create a small board on which to make the connections and solder them, thus further reducing the number of cables.
In any case, by following the diagram, everyone can optimize their own wiring and adapt it to their own ship model.
Hi Alessandro. When I first looked at this my first thought was how do you control the hysteresis when auto switching batteries. Then after looking at the video I realised it was a manual operation. I can't see anything wrong with it and it would work for any type of battery.
ELECTRIC POWER SYSTEM THAT ALLOWS SWITCHING FROM A MAIN BATTERY TO A SPARE BATTERY, FOR SAFER NAVIGA
Hi Alessandro. When I first looked at this my first thought was how do you control the hysteresis when auto switching batteries. Then after looking at the video I realised it was a manual operation. I can't see anything wrong with it and it would work for any type of battery.
Hello.. Very good idea, and choice of components. Except for me I would have chosen Li ion Battery's, the reason being there are commercially available low volt's Audio and digital readout indicator for these cells. Not sure about Lead Acid battery's/Jelly cells, low voltage indicators were around years ago but not seen any advertised of late.
Regards Muddy ( Brian )
ELECTRIC POWER SYSTEM THAT ALLOWS SWITCHING FROM A MAIN BATTERY TO A SPARE BATTERY, FOR SAFER NAVIGA
Hello.. Very good idea, and choice of components. Except for me I would have chosen Li ion Battery's, the reason being there are commercially available low volt's Audio and digital readout indicator for these cells. Not sure about Lead Acid battery's/Jelly cells, low voltage indicators were around years ago but not seen any advertised of late.
Regards Muddy ( Brian )
ELECTRIC POWER SYSTEM THAT ALLOWS SWITCHING FROM A MAIN BATTERY TO A SPARE BATTERY, FOR SAFER NAVIGA
Mama Mia ... that's a lotta wires!
Dave B
So far my collection resembles "The Island of Misfit Toys". I've picked up several boats that are old builds and have been neglected. I'm giving them the TLC they need, hoping to bring them back to their former glory. Once I get enough practice/ experience I intend to take on a full build.
ELECTRIC POWER SYSTEM THAT ALLOWS SWITCHING FROM A MAIN BATTERY TO A SPARE BATTERY, FOR SAFER NAVIGATION.
Before potentially moving this topic to the Wiki section and making it easily accessible to everyone, I'm submitting it to the forum so that it can be reviewed by those more experienced than I.
I previously demonstrated an electric motor power and control system that automatically switched on a backup battery when the main battery was low.
While the system worked, it didn't seem very useful if it didn't indicate when the first battery was low or if it didn't indicate when switching from the main to the secondary battery. The LED signaling system seemed ineffective during the day and from a distance.
I know that many radios provide charge status information, but this is a self-contained alternative system.
This setup (see diagram and real-world test, first and second attached images) includes the ability to switch power from one battery to the other.
Therefore, it will be possible to switch from the main battery to the backup battery as soon as you notice that the first is running low.
It will be possible to switch even if the main battery is completely flat or even damaged.
The system requires the use of four separate batteries but can be simplified to just two, as we'll see at the end of the explanation.
I made the diagram and practical test with four separate batteries for better understanding.
Don't worry about the size of the individual batteries; I used the ones I had available just to make the system work. You can use whatever technologies you like.
Explanation of Connections
As you can see in the diagram, battery 1 is the one normally used as the main battery (in this case, I used a 6-volt, 4.5 Ah AGM lead-acid battery, but any other technology will work).
Battery 2 is the one that will take over as a backup for our control (as above for the battery type).
The system is designed so that there is no possibility of them working together, so there will never be an accidental parallel between a flat battery and a charged one.
There is a dedicated battery for the receiver, the servos, the switches, and in short, all the loads connected to the receiver channels (as above for the battery type).
The ESC's BEC was not used, but a separate power supply was used for obvious reasons; otherwise, the system would not have worked properly.
Finally, there is a dedicated battery for energizing the relay coil. Since the relay (see photos 3 and 4) is 12 Volts 80 Amps, I couldn't use 6 Volt batteries to avoid overcomplicating the diagram and making it difficult to understand. (In this case, I used a 12 Volt, 2 Ah AGM lead-acid battery, but any other technology will do.)
A brief aside on the choice of relay.
It's a changeover relay with five contacts: two for the coil, one is the common contact, and the other two are the normally open and normally closed contacts. The relay switches between them.
I would have preferred a 6 Volt relay, but the ones I had didn't support high enough currents on the contacts. The ones I needed were too expensive. I paid less than two euros for these 12 Volt ones, including shipping.
They're the ones for cars, and 12 Volts is very common.
So, as already mentioned, a battery is connected to the receiver.
The negative terminal of battery 1 (main) is connected, together with the negative terminal of battery 2 (reserve), to the negative terminal of the ESC.
The positive terminal of battery 1 (main) is connected to the normally closed contact of the relay.
The positive terminal of battery 2 (reserve) is connected to the normally open contact of the relay.
The common contact of the relay is connected to the positive terminal of the ESC. (It is advisable to insert a fuse here.)
The ESC is connected to the motor with the two usual cables.
The ESC is connected to the receiver (with the positive isolated) with only the negative and signal wires (in this case, the active channel is channel 3, which corresponds to the left up and down lever on the radio control).
The relay coil contacts are connected to the two wires (out) of the ON-OFF RX Switch.
There is a diode between the relay coil contacts for protection only (it is not essential for operation).
The positive and negative input wires of the aforementioned ON-OFF RX Switch are connected to the 12-volt battery.
The three joined wires (signal-positive-negative) of the ON-OFF RX Switch are connected to the receiver (in this specific case, they are connected to channel 6, which corresponds to the knob on the top right of the remote control).
The ON-OFF RX Switch will draw power and commands from the receiver itself.
How the system works (see video)
Moving the left remote control lever (up and down) activates the motor, accelerating and decelerating in both forward and reverse.
In this condition (relay coil not energized), the ESC will draw current only from battery 1 (main) via the normally closed relay contact.
When we notice that the battery is discharging too much because the boat is slow (even with the lever fully up), or is completely flat because the boat is stationary, we will switch the power supply.
In the video, total battery discharge is simulated by disconnecting the negative terminal of the main battery (which in the real test is the right one) by removing the alligator clip.
At this point, you can see the electric motor stop even though the remote control lever is still fully forward.
Now simply turn the knob on the top right of the remote control. This way (on channel 6 of the receiver), the ON command will reach the ON-OFF RX Switch. This will pass current that will energize the relay coil. Energizing the coil will cause the contacts to switch; therefore, the circuit of battery 1 will open and that of battery 2 will close.
The boat can be brought back to shore, now using the full charge of the reserve battery.
If space is a concern and you want to minimize the number of batteries needed, here's what you can do.
Reduce the number of batteries to three (instead of four).
In this case, we could eliminate the battery used to power the receiver (and consequently all the loads connected to it via the channel slots), but this would not restore the positive of the BEC; absolutely not.
Battery 2 (the reserve) must also be connected to the positive and negative terminals of the receiver. All other connections should be left as they were.
There is a disadvantage, or at least an aspect to consider.
In this case, battery 2, a backup battery, will not be fully charged if needed because it will have to power the receiver, servos, any lights, etc., throughout the entire navigation.
The current draw will certainly not be as high as the motor, but it must be taken into account.
If necessary, I will make this second diagram.
Reduce the number of batteries to two (instead of four).
In this case, eliminate the two 6-volt batteries and use the 12-volt battery to power the coil, the receiver, and the ESC in case of a backup, taking care to lower the voltage to 6 volts for these two loads in parallel.
If necessary, I will make this third diagram.
I hope this is helpful.
For those less experienced, follow all the connections carefully, following the diagram to the letter.
Please give me some time to review the translation errors.
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ELECTRIC POWER SYSTEM THAT ALLOWS SWITCHING FROM A MAIN BATTERY TO A SPARE BATTERY, FOR SAFER NAVIGA
ELECTRIC POWER SYSTEM THAT ALLOWS SWITCHING FROM A MAIN BATTERY TO A SPARE BATTERY, FOR SAFER NAVIGATION.
Before potentially moving this topic to the Wiki section and making it easily accessible to everyone, I'm submitting it to the forum so that it can be reviewed by those more experienced than I.
I previously demonstrated an electric motor power and control system that automatically switched on a backup battery when the main battery was low.
While the system worked, it didn't seem very useful if it didn't indicate when the first battery was low or if it didn't indicate when switching from the main to the secondary battery. The LED signaling system seemed ineffective during the day and from a distance.
I know that many radios provide charge status information, but this is a self-contained alternative system.
This setup (see diagram and real-world test, first and second attached images) includes the ability to switch power from one battery to the other.
Therefore, it will be possible to switch from the main battery to the backup battery as soon as you notice that the first is running low.
It will be possible to switch even if the main battery is completely flat or even damaged.
The system requires the use of four separate batteries but can be simplified to just two, as we'll see at the end of the explanation.
I made the diagram and practical test with four separate batteries for better understanding.
Don't worry about the size of the individual batteries; I used the ones I had available just to make the system work. You can use whatever technologies you like.
Explanation of Connections
As you can see in the diagram, battery 1 is the one normally used as the main battery (in this case, I used a 6-volt, 4.5 Ah AGM lead-acid battery, but any other technology will work).
Battery 2 is the one that will take over as a backup for our control (as above for the battery type).
The system is designed so that there is no possibility of them working together, so there will never be an accidental parallel between a flat battery and a charged one.
There is a dedicated battery for the receiver, the servos, the switches, and in short, all the loads connected to the receiver channels (as above for the battery type).
The ESC's BEC was not used, but a separate power supply was used for obvious reasons; otherwise, the system would not have worked properly.
Finally, there is a dedicated battery for energizing the relay coil. Since the relay (see photos 3 and 4) is 12 Volts 80 Amps, I couldn't use 6 Volt batteries to avoid overcomplicating the diagram and making it difficult to understand. (In this case, I used a 12 Volt, 2 Ah AGM lead-acid battery, but any other technology will do.)
A brief aside on the choice of relay.
It's a changeover relay with five contacts: two for the coil, one is the common contact, and the other two are the normally open and normally closed contacts. The relay switches between them.
I would have preferred a 6 Volt relay, but the ones I had didn't support high enough currents on the contacts. The ones I needed were too expensive. I paid less than two euros for these 12 Volt ones, including shipping.
They're the ones for cars, and 12 Volts is very common.
So, as already mentioned, a battery is connected to the receiver.
The negative terminal of battery 1 (main) is connected, together with the negative terminal of battery 2 (reserve), to the negative terminal of the ESC.
The positive terminal of battery 1 (main) is connected to the normally closed contact of the relay.
The positive terminal of battery 2 (reserve) is connected to the normally open contact of the relay.
The common contact of the relay is connected to the positive terminal of the ESC. (It is advisable to insert a fuse here.)
The ESC is connected to the motor with the two usual cables.
The ESC is connected to the receiver (with the positive isolated) with only the negative and signal wires (in this case, the active channel is channel 3, which corresponds to the left up and down lever on the radio control).
The relay coil contacts are connected to the two wires (out) of the ON-OFF RX Switch.
There is a diode between the relay coil contacts for protection only (it is not essential for operation).
The positive and negative input wires of the aforementioned ON-OFF RX Switch are connected to the 12-volt battery.
The three joined wires (signal-positive-negative) of the ON-OFF RX Switch are connected to the receiver (in this specific case, they are connected to channel 6, which corresponds to the knob on the top right of the remote control).
The ON-OFF RX Switch will draw power and commands from the receiver itself.
How the system works (see video)
Moving the left remote control lever (up and down) activates the motor, accelerating and decelerating in both forward and reverse.
In this condition (relay coil not energized), the ESC will draw current only from battery 1 (main) via the normally closed relay contact.
When we notice that the battery is discharging too much because the boat is slow (even with the lever fully up), or is completely flat because the boat is stationary, we will switch the power supply.
In the video, total battery discharge is simulated by disconnecting the negative terminal of the main battery (which in the real test is the right one) by removing the alligator clip.
At this point, you can see the electric motor stop even though the remote control lever is still fully forward.
Now simply turn the knob on the top right of the remote control. This way (on channel 6 of the receiver), the ON command will reach the ON-OFF RX Switch. This will pass current that will energize the relay coil. Energizing the coil will cause the contacts to switch; therefore, the circuit of battery 1 will open and that of battery 2 will close.
The boat can be brought back to shore, now using the full charge of the reserve battery.
If space is a concern and you want to minimize the number of batteries needed, here's what you can do.
Reduce the number of batteries to three (instead of four).
In this case, we could eliminate the battery used to power the receiver (and consequently all the loads connected to it via the channel slots), but this would not restore the positive of the BEC; absolutely not.
Battery 2 (the reserve) must also be connected to the positive and negative terminals of the receiver. All other connections should be left as they were.
There is a disadvantage, or at least an aspect to consider.
In this case, battery 2, a backup battery, will not be fully charged if needed because it will have to power the receiver, servos, any lights, etc., throughout the entire navigation.
The current draw will certainly not be as high as the motor, but it must be taken into account.
If necessary, I will make this second diagram.
Reduce the number of batteries to two (instead of four).
In this case, eliminate the two 6-volt batteries and use the 12-volt battery to power the coil, the receiver, and the ESC in case of a backup, taking care to lower the voltage to 6 volts for these two loads in parallel.
If necessary, I will make this third diagram.
I hope this is helpful.
For those less experienced, follow all the connections carefully, following the diagram to the letter.
Please give me some time to review the translation errors.
