charging 6 volt and 12 volt batteries with generator
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charging 6 volt and 12 volt batteries with generator
Searched the forums but could not find a answer to this.
Is there a way to charge the 6 volt starting battery and a 12 volt accessory battery or two 6 volt batteries in series with the generator so I don't have to charge the 12 volt accessory battery with a battery charger. Like this option as I would like to add a wireless O2 sensor, temperature gauge and tachometer
If that's not an option is there a problem with running the original headlights, tail lights and aftermarket 6 volt blinkers, brake lights and running lights off the starting battery and would there be a problem using 6 volt LED lights in everything.
Bruce
Is there a way to charge the 6 volt starting battery and a 12 volt accessory battery or two 6 volt batteries in series with the generator so I don't have to charge the 12 volt accessory battery with a battery charger. Like this option as I would like to add a wireless O2 sensor, temperature gauge and tachometer
If that's not an option is there a problem with running the original headlights, tail lights and aftermarket 6 volt blinkers, brake lights and running lights off the starting battery and would there be a problem using 6 volt LED lights in everything.
Bruce
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Re: charging 6 volt and 12 volt batteries with generator
In theory, you could set up two 6 V batteries in series and charge them off the T generator, but I doubt it would be worthwhile. You'd still have poor regulation and limited current available.
The better solution is to charge the 12 volt accessory battery using the magneto battery charger setup and leave the T system stock.
All LED lights work fine and reduce demand on the power source dramatically. They are available in 6 or 12 volts.
You can add a temp gauge and tach using 6 volts. My car has a period-looking electric tach that runs on the stock T system. I don't know who made it, but it looks good and works well. Model T Ranch in Spokane might be a source. Non-electric temp gauges are widely available.
I don't know what you're going to connect the 02 sensor to, but the sensor itself probably does not need 12 volts. If you're going to run a fuel injection system, you'd probably be way ahead to use an alternator and full 12 volt system, including ignition and starter.
The better solution is to charge the 12 volt accessory battery using the magneto battery charger setup and leave the T system stock.
All LED lights work fine and reduce demand on the power source dramatically. They are available in 6 or 12 volts.
You can add a temp gauge and tach using 6 volts. My car has a period-looking electric tach that runs on the stock T system. I don't know who made it, but it looks good and works well. Model T Ranch in Spokane might be a source. Non-electric temp gauges are widely available.
I don't know what you're going to connect the 02 sensor to, but the sensor itself probably does not need 12 volts. If you're going to run a fuel injection system, you'd probably be way ahead to use an alternator and full 12 volt system, including ignition and starter.
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Re: charging 6 volt and 12 volt batteries with generator
Dual battery systems have been used, usually on heavy duty equipment. All of them I've ever seen use a pair of identical batteries, in the case of some older Cat bulldozers, 2 large 12 volt batteries connected in series and operating a 24 volt starter and charged by a 24 volt alternator.
I have an old Mack truck that uses a series/parallel setup. It uses 2 big 12 volt batteries that are normally in parallel and charged by a large 12 volt generator. When the 24 volt starter is engaged, a large solenoid switch puts the batteries in series to crank the engine at 24 volts. When the starter button is released, the system goes back to 12 volts. This thing originally had 4 large 6 volt batteries, with 2 pairs, each connected in series to give 12 volts except when the starter was engaged, when all 4 were placed in series to provide 24 volts.
I have an old Mack truck that uses a series/parallel setup. It uses 2 big 12 volt batteries that are normally in parallel and charged by a large 12 volt generator. When the 24 volt starter is engaged, a large solenoid switch puts the batteries in series to crank the engine at 24 volts. When the starter button is released, the system goes back to 12 volts. This thing originally had 4 large 6 volt batteries, with 2 pairs, each connected in series to give 12 volts except when the starter was engaged, when all 4 were placed in series to provide 24 volts.
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Re: charging 6 volt and 12 volt batteries with generator
Bruce,
Fortunately it's easy and inexpensive to do this today. You simply need a current and voltage adjustable dc boost converter that can be powered from the 6V battery+generator and will charge a 12V battery at a constant current 'till it reaches a certain voltage and will then maintain that (or better still will drop to a 'float' voltage).
If you adjust this to trickle charge the 12V battery at say 1A that'd require ~2A from the 6V, not a huge drain - this is just a suggestion as you can set it to what you want, although you need to be careful of the limitations of the T electrical system. You'd also need to ensure it wasn't draining from the 6V battery when the motor is not running, there are many ways to 'automate' this, or you could simply use a switch.
Prices for such a thing start at around $3+ shipping for a small 10A-capable unit. YMMV a little in terms of how much the electrical noise of a T might affect such a thing, but it's an inexpensive trial and should be sortable, if needed.
There are other alternatives, including separately charging a 12V battery from the generator and then using a buck converter/regulator to the 6V system, but this would be more complex to set up.
Personally I'd just change the car to a single 12V system as it'd be the simplest and most proven thing to do.
Luke.
Fortunately it's easy and inexpensive to do this today. You simply need a current and voltage adjustable dc boost converter that can be powered from the 6V battery+generator and will charge a 12V battery at a constant current 'till it reaches a certain voltage and will then maintain that (or better still will drop to a 'float' voltage).
If you adjust this to trickle charge the 12V battery at say 1A that'd require ~2A from the 6V, not a huge drain - this is just a suggestion as you can set it to what you want, although you need to be careful of the limitations of the T electrical system. You'd also need to ensure it wasn't draining from the 6V battery when the motor is not running, there are many ways to 'automate' this, or you could simply use a switch.
Prices for such a thing start at around $3+ shipping for a small 10A-capable unit. YMMV a little in terms of how much the electrical noise of a T might affect such a thing, but it's an inexpensive trial and should be sortable, if needed.
There are other alternatives, including separately charging a 12V battery from the generator and then using a buck converter/regulator to the 6V system, but this would be more complex to set up.
Personally I'd just change the car to a single 12V system as it'd be the simplest and most proven thing to do.
Luke.
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Re: charging 6 volt and 12 volt batteries with generator
It would be as simple as a switch to convert the generator output to the 12V battery. You would need a diode cutout. The generator dont care what voltage its charging. 6, 8 or 12V. You would want to reset the generator output to roughly 1/2 of what you normally charge your 6V system.3-4 volts would be plenty for both 6& 12V needs. The lower charge rate keeps the generator from working too hard on 12V.
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Re: charging 6 volt and 12 volt batteries with generator
Simply charge the 12 Volt battery from a Magneto Battery trickle charger.
Respectfully Submitted,
Be_Zero_Be
I drive a Model T ... Microseconds don't matter
For every Absolute Model T Fact there are at least three exceptions.
Be_Zero_Be
I drive a Model T ... Microseconds don't matter

For every Absolute Model T Fact there are at least three exceptions.
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Re: charging 6 volt and 12 volt batteries with generator
Didn’t know there was such a thing as a magneto charger, did a search and see you can build your own with a light and diode thing but what is a magneto trickle charger?
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Re: charging 6 volt and 12 volt batteries with generator
It's the same thing, 'trickle' simply refers to the fact that it's not a high-current charger and would take a while to charge a battery. Depending upon what you're also drawing from the battery a trickle charger may not even keep up with that and the battery will eventually go flat.
Luke.
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Re: charging 6 volt and 12 volt batteries with generator
If you want all those accessories, why don't you drive a modern car? The T works fine just as Henry built it. However, it would seem to me that if you wanted to use all those 12 volt accessories, they wouldn't draw much out of a 12 volt battery, so you could charge the 12 volt battery when the car is parked, and use the 6 volt for everything else with the original generator.
There is also another solution. That would be to re-wind the starter for 12 volts and use 12 volt bulbs in the lights. The T generator will charge a 12 volt battery. T's don't like alternators. I have seen a lot of T's on tours which had alternator problems.
Norm
There is also another solution. That would be to re-wind the starter for 12 volts and use 12 volt bulbs in the lights. The T generator will charge a 12 volt battery. T's don't like alternators. I have seen a lot of T's on tours which had alternator problems.
Norm
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Re: charging 6 volt and 12 volt batteries with generator
I use a 6-12v converter when I need to run 12v accessories in my T. The only thing I ever seem to use off it is the car fridge. The USB cigarette lighter converter plug I have still regulates perfectly well with 6V input.
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Re: charging 6 volt and 12 volt batteries with generator
Can we start from the beginning of what your goal is rather than jumping to possible solutions?bmklawt wrote: ↑Tue Aug 08, 2023 7:55 pmSearched the forums but could not find a answer to this.
Is there a way to charge the 6 volt starting battery and a 12 volt accessory battery or two 6 volt batteries in series with the generator so I don't have to charge the 12 volt accessory battery with a battery charger. Like this option as I would like to add a wireless O2 sensor, temperature gauge and tachometer
If that's not an option is there a problem with running the original headlights, tail lights and aftermarket 6 volt blinkers, brake lights and running lights off the starting battery and would there be a problem using 6 volt LED lights in everything.
Bruce
You said you want to add a wireless O2 sensor, temperature gauge and tachometer & running headlights, tail, brake & running lights.
Best to understand the total load on the electrical system from each component since there are options to go mechanical, 6v or 12v.
Keep in mind that many gauge's voltage specs are related to illuminating the gauge's bulb and not necessarily its sensor. In that case a 12v can use a 6v bulb or none to eliminate the load on the system
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The following is just for estimates and others to chime in choices & calculations
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The temperature gauge can have a mechanical sensor vs an electronic one.
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Not sure what O2 wireless sensor you are referring to. The one noted below uses a 12v bulb but the sensor wasn't noted likely much less
A narrowband O2 (Oxygen) sensor only reads either rich or lean of Stoichiometric. Stoich is the ratio to completely combust the fuel. So a narrowband will only read rich or lean. It does not tell you how far away you are from Stoich.
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Don't know what tach you have in mind but likely not much to drive it, just the illumination issue.
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Lights can be the major draw : 2 headlights, 2 rear taillights, daytime running lights (use headlights on dim)
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System load estimates
4 filament bulbs 8 amps
4 led bulbs 4 amps
6v to12v boost converter with 2 amp output to drive sensors 4 amps
so either 8 or 12 amp load depending on bulbs
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Charging a battery needs volts charge it (voltage regulator) available amps determines the length of time to charge (trickle charge vs Engine starter/charger.
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So do the math or just settle for an 12v alternator
The past is a great place and I don't want to erase it or to regret it, but I don't want to be its prisoner either.
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Topic author - Posts: 234
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Re: charging 6 volt and 12 volt batteries with generator
I don't know much about electronics but can muddle my way through with a bunch of hand holding.
The turn signal and running light are for safety the other stuff is just for fun. What I would like is to be able to read on my Iphone, O2 sensor, temp, RPM and GPS. The O2 sensor is so I know what is correct for lean, rich, read lots of good advice on how to set this by feel and sound but I want to see it until I know for sure, same for temp and RPM, I just thought it would be cool. An Iphone APP to show all this is the easy part, just ask my friend to write me an APP.
A project I'm working on now is a 1920's rotary candlestick "cell" phone for the Model T, have a working model just need to figure out how to get it into a vintage candlestick phone.
The turn signal and running light are for safety the other stuff is just for fun. What I would like is to be able to read on my Iphone, O2 sensor, temp, RPM and GPS. The O2 sensor is so I know what is correct for lean, rich, read lots of good advice on how to set this by feel and sound but I want to see it until I know for sure, same for temp and RPM, I just thought it would be cool. An Iphone APP to show all this is the easy part, just ask my friend to write me an APP.
A project I'm working on now is a 1920's rotary candlestick "cell" phone for the Model T, have a working model just need to figure out how to get it into a vintage candlestick phone.
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Re: charging 6 volt and 12 volt batteries with generator
Feel and sound will serve you better than an 02 reading. The T engine probably runs best a little richer than stoichiometric, and in any case, ambient conditions and whether the engine is warmed up or not, engine condition, elevation, and just about everything else under the sun, will affect ideal settings. Making adjustments by ear and feel is easy and effective, and the convenient fingertip controls allow for ease of adjustment without taking your eyes off the road or your hands off the wheel.
A Garmin device uses very little power and it will give you enough information at a glance to determine RPM, along with speedometer and odometer functions and more. Stick it on the windshield or dash, feed it 12 VDC, and you're good to go.
A Garmin device uses very little power and it will give you enough information at a glance to determine RPM, along with speedometer and odometer functions and more. Stick it on the windshield or dash, feed it 12 VDC, and you're good to go.
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Re: charging 6 volt and 12 volt batteries with generator
Is there an interface device that will allow a rotary dial phone to work on modern phone networks?
Maybe some genius will come up with a really good AI robotic telephone operator. Just dial "0", and she'll connect you with anyone from satan to Jesus Christ anywhere on Earth ... if you have enough nickles.
Maybe some genius will come up with a really good AI robotic telephone operator. Just dial "0", and she'll connect you with anyone from satan to Jesus Christ anywhere on Earth ... if you have enough nickles.
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Re: charging 6 volt and 12 volt batteries with generator
Hi Bruce,
You may want to go fishing with this can of worms
I love gadgets too, I also like lots of info. I find ( oh god I'm not sure I want to say this)
that Moto meters are very unreliable so I install a Stewart Warner mechanical Temp. gauge in my T's so I know what the engine temp is.
As far as a tach they make a very inexsensive ( self contained) battery unit for rental & industrial engines that has a pickup wire that
wraps around a plug wire for the signal. and can be programed for 1-2-3-4-6-8 & 10 cylinders. I do not believe the tach will work on T coils
because multiple spark pulses will confuse it. I did not know there was a O2 sensor App. but non heated O2 sensors work off a 5.5 volt input
signal so 6vdc & a resistor should work. I think what you are looking for is a air/fuel ratio meter. They are 12vdc & mostly for tuning & racing
will run on a sealed battery for months on a charge and I think they may give you a lot of information that is irrelivant to Model T's. I use a
tach more to ensure I don't lug the engine to much rather than over rev it. As far as iphone apps most of us don't have enough thumbs to
drive a T & use a app @ the same time in a safe mannor. If you are new to Model T's I would like to make a suggestion. Part of the hobby is
driving very old cars like they used to. Try removing some of the seat padding, wearing thinner underwear & try doing it by the seat of your
pants. It's a lot of fun. I just did some racing with a onboard computer & I hate having a computer remind me just how bad I F---ed up that last
turn not to mention it recorded it in a down loadable format.
Hope I didn't offend you & hope I helped a little.
Craig.
You may want to go fishing with this can of worms

that Moto meters are very unreliable so I install a Stewart Warner mechanical Temp. gauge in my T's so I know what the engine temp is.
As far as a tach they make a very inexsensive ( self contained) battery unit for rental & industrial engines that has a pickup wire that
wraps around a plug wire for the signal. and can be programed for 1-2-3-4-6-8 & 10 cylinders. I do not believe the tach will work on T coils
because multiple spark pulses will confuse it. I did not know there was a O2 sensor App. but non heated O2 sensors work off a 5.5 volt input
signal so 6vdc & a resistor should work. I think what you are looking for is a air/fuel ratio meter. They are 12vdc & mostly for tuning & racing
will run on a sealed battery for months on a charge and I think they may give you a lot of information that is irrelivant to Model T's. I use a
tach more to ensure I don't lug the engine to much rather than over rev it. As far as iphone apps most of us don't have enough thumbs to
drive a T & use a app @ the same time in a safe mannor. If you are new to Model T's I would like to make a suggestion. Part of the hobby is
driving very old cars like they used to. Try removing some of the seat padding, wearing thinner underwear & try doing it by the seat of your
pants. It's a lot of fun. I just did some racing with a onboard computer & I hate having a computer remind me just how bad I F---ed up that last
turn not to mention it recorded it in a down loadable format.
Hope I didn't offend you & hope I helped a little.
Craig.
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Re: charging 6 volt and 12 volt batteries with generator
An 02 sensor would depend on a tight intake and exhaust system and a tight engine to provide
meaningful data. The location of the sensor in the system would also be critical.
Lacking a method of making continual corrections to the fuel/air mix, as would be available with a modern fuel injection system, most of the information would be of little use.
Running a T engine at the absolute leanest A/F possible is not desireable, since performance and driveability suffers, and over time, issues with exhaust valves and exhaust manifolds could be expected.
Modern computerized engines use an 02 sensor in combination with a number of other sensors and inputs to manage fuel mixture, spark timing, operating temperature, and EGR to minimize "emissions" and maximize fuel economy consistent with good performance.
With an unmodified Model T, you are both the sensor array and the computer/management system and the servo-actuator that makes the physical adjustments to meet the requirements of the situation.
meaningful data. The location of the sensor in the system would also be critical.
Lacking a method of making continual corrections to the fuel/air mix, as would be available with a modern fuel injection system, most of the information would be of little use.
Running a T engine at the absolute leanest A/F possible is not desireable, since performance and driveability suffers, and over time, issues with exhaust valves and exhaust manifolds could be expected.
Modern computerized engines use an 02 sensor in combination with a number of other sensors and inputs to manage fuel mixture, spark timing, operating temperature, and EGR to minimize "emissions" and maximize fuel economy consistent with good performance.
With an unmodified Model T, you are both the sensor array and the computer/management system and the servo-actuator that makes the physical adjustments to meet the requirements of the situation.
Last edited by TXGOAT2 on Thu Aug 10, 2023 10:33 am, edited 1 time in total.
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Re: charging 6 volt and 12 volt batteries with generator
Yes, you need a Dialgzimo to generate the DTMF tones from the decadic dial. https://www.dialgizmo.com/
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Re: charging 6 volt and 12 volt batteries with generator
Yes , not only is there a device you can buy its a complete kit & requires no soldering - Available in several colorsTXGOAT2 wrote: ↑Wed Aug 09, 2023 11:04 pmIs there an interface device that will allow a rotary dial phone to work on modern phone networks?
Maybe some genius will come up with a really good AI robotic telephone operator. Just dial "0", and she'll connect you with anyone from satan to Jesus Christ anywhere on Earth ... if you have enough nickles.
describes it https://hackaday.com/2022/09/10/the-ope ... ars-later/
shows assembly https://youtu.be/uV1C-41tq64
The past is a great place and I don't want to erase it or to regret it, but I don't want to be its prisoner either.
Mick Jagger
Mick Jagger
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Topic author - Posts: 234
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Re: charging 6 volt and 12 volt batteries with generator
TRDxB2, that rotary cell phone is exactly what I have
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Re: charging 6 volt and 12 volt batteries with generator
Several years ago I changed my 1924 touring to a dual voltage system. For the starter and horn, they remained on the 6 volt battery. The 6 volt current is much kinder to the bendix and ring gear. To charge the 6V battery I got a device from Fun Projects that takes the current from the magneto and sends it to the 6 volt battery.
For ignition and lighting, I put in a 12 volt alternator (Delco, I think) that charges the separate 12 volt battery. I also have a True Fire that runs off of this. And with 12 volt lighting, driving at night is much safer too - I have people coming opposite me flashing me to turn off my high beams
Best thing is everything is easily reversible back to stock.
Bob Sacchi
For ignition and lighting, I put in a 12 volt alternator (Delco, I think) that charges the separate 12 volt battery. I also have a True Fire that runs off of this. And with 12 volt lighting, driving at night is much safer too - I have people coming opposite me flashing me to turn off my high beams
Best thing is everything is easily reversible back to stock.
Bob Sacchi