0

I wanted to know if 3 3.7 volts 6000 mah hour batteries power 2 9 watt bulbs, and a 12-volt pc case fan? If so for how long?

Rahul Vijayan
  • 45
  • 5
  • @CharlesCowie I might be mistaken but would it be (3.7v) (6A)= 22.2-watt hours. Since it is two 9 watt bulbs so 18 watts, it would be 22.2/18 which = 1.23 hours. I think this is correct but I am not sure how to add a 12-volt fan in there. Also, I think that is for 1 battery but I am adding 3 so would it go up from 1.23 hours? – Rahul Vijayan Aug 20 '20 at 02:56
  • 3*3.3=9.9V. So it is not possible to power 12V device directly. – G-aura-V Aug 20 '20 at 03:04
  • @Giga-Byte So if I were to add another battery then I would be able to power a 12-volt fan. If so for how long? – Rahul Vijayan Aug 20 '20 at 03:12
  • Adding another one will give you 13.2V which is higher than rated voltage. Devices are supposed to be powered by exactly what they need. And "how long" depends on the current consumption of your fan. – G-aura-V Aug 20 '20 at 03:14
  • @Giga-Byte so what do you suggest I do. The fan should still run when underpowered, Just not at full speed which is okay in my case. – Rahul Vijayan Aug 20 '20 at 03:25
  • Using a 12V regulator might do the job. But I am sure better suggestions are coming. So you might choose to wait. – G-aura-V Aug 20 '20 at 03:27
  • What voltage are your 9W bulbs? – Solar Mike Aug 20 '20 at 04:10
  • To answer your question we will need part numbers for all parts that you want to use. As well as a schematic or at least a description of how everything will be hooked up. – Drew Aug 20 '20 at 04:14
  • @Messifanra, you are correct. You have 22.2 watt hours available from each battery. Also it is probably ok to use 11 volts for a 12-volt fan. Using higher than rated voltage on anything is much more likely to cause failure. You need to know the fan current to calculate how long it will run. The run-time calculation is really just an estimate. It depends on how far you want to discharge the battery and how much power the fan uses at reduced speed. –  Aug 20 '20 at 13:50
  • @SolarMike is it 9 watts .17 amps and roughly 52 volts. but since I have 6000 mah then 3.7 volts should be fine right? – Rahul Vijayan Aug 20 '20 at 14:57
  • @CharlesCowie ok but would running a fan at 9.9 v be fine? – Rahul Vijayan Aug 20 '20 at 14:59
  • You have not given any details about the fan, but I assume that it has a brushless permanent magnet motor with a built in electronic commutator. That is likely to run fine with reduced voltage, but not guaranteed. Unless you found something from the manufacturer that says it is ok, you can'r know for sure. I would be inclined to try it. If it seems to run ok, it is probably ok. –  Aug 20 '20 at 15:35
  • @CharlesCowie I think I will just run 14.8 volts thorough a 12-volt regulator and then run it through the fan. That might be a safer bet. – Rahul Vijayan Aug 20 '20 at 15:43

0 Answers0