How to get +12 and -12 from car battery.
- Thread starter Metalica
- Start date
If you used two 12v sealed lead acid batteries in series, that would work.
Don't use automotive or marine battery inside a dwelling, as they will emit hydrogen and osxygen gases.
If you're planning on using it in an automobile, then you will need an inverter (negative DC-DC converter) to supply the negative portion.
Don't use automotive or marine battery inside a dwelling, as they will emit hydrogen and osxygen gases.
If you're planning on using it in an automobile, then you will need an inverter (negative DC-DC converter) to supply the negative portion.
Yeh so i guess their is not other option then to use an inverter, since the car has only one battery supplying +12 with reference to the cars body.
Could their be some other way to get -12 v and +12v from the cars batter to power the above diagram......?
No inverters plz..................
Could their be some other way to get -12 v and +12v from the cars batter to power the above diagram......?
No inverters plz..................
You could use a SMPS.
Here is one project for supplying ±35V.
It shouldn't be too difficult to modify it to supply ±12V.
http://sound.westhost.com/project89.htm
Here is one project for supplying ±35V.
It shouldn't be too difficult to modify it to supply ±12V.
http://sound.westhost.com/project89.htm
How much current do you need for the -12V? If it is only a few mA, then there are devices, such as the ICL7660A, that will do that. You could also consider carrying a separate, smaller battery for the -12V.
On the topic of safety, I think the risk of using a lead-acid battery, particularly a sealed lead-acid battery, in a dwelling is a bit overstated. Certainly, an explosion in a garage would be serious, and it is quite common to have batteries and to charge them there. Explosions are rare and almost always result from doing a dumb thing. In addition, less than 1% of hydrogen produced by a sealed battery is released (http://www.vonwentzel.net/Battery/00.Glossary/). Production of relatively tiny amounts of hydrogen in a home is not dangerous. All homes are ventilated. Moreover, humans produce on average about 1.2 L of hydrogen per day per person*, and there has never been a home explosion related to that -- even in homes filled with people and pets.
John
*Calculation:
1) 361 mL of hydrogen per day in our flatus (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1378885/ ; and http://www.heptune.com/farts.html)
2) Roughly 850 mL of hydrogen per day in our breath (http://www.ncbi.nlm.nih.gov/pubmed/9925135 ; and http://www.arb.ca.gov/research/resnotes/notes/94-11.htm)
On the topic of safety, I think the risk of using a lead-acid battery, particularly a sealed lead-acid battery, in a dwelling is a bit overstated. Certainly, an explosion in a garage would be serious, and it is quite common to have batteries and to charge them there. Explosions are rare and almost always result from doing a dumb thing. In addition, less than 1% of hydrogen produced by a sealed battery is released (http://www.vonwentzel.net/Battery/00.Glossary/). Production of relatively tiny amounts of hydrogen in a home is not dangerous. All homes are ventilated. Moreover, humans produce on average about 1.2 L of hydrogen per day per person*, and there has never been a home explosion related to that -- even in homes filled with people and pets.
John
*Calculation:
1) 361 mL of hydrogen per day in our flatus (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1378885/ ; and http://www.heptune.com/farts.html)
2) Roughly 850 mL of hydrogen per day in our breath (http://www.ncbi.nlm.nih.gov/pubmed/9925135 ; and http://www.arb.ca.gov/research/resnotes/notes/94-11.htm)
