I'm basically trying to make the brightest LED bar light for video that I can which runs off of the most commonly used NPF 8v batteries.
I've been experimenting with these 2835 LED strips. I have cut it to 1 metre which has 240 LED's and to my understanding wants 24v and apx 1.5amps or 36W (180WattsPer5meters/5=36/24v=1.5a). I chose these because they seem to be the most efficient LED's out there and are low heat (which I assume is related to efficiency)
This NPF battery claims to have 8000mAh and while that's probably a vast exaggeration, in my understanding there should be enough juice to power these lights at full power for somewhere between 1-1.5 hrs. (8amps X 8v = 64Wh). Now I've also read that these NPF batteries have a max 5A discharge auto cutoff which is just above my calculated needs.
I've been using this Boost Converter to adjust output current/voltage which is rated for somewhere between 35-50W. I rigged it all up and adjusted the voltage to 24 and connect the LED with a low current. This low current kept the starting voltage below turning on point. As I raised the current I eventually got to 23 volts and 1.5 amps output and a very bright light strip. Any higher and the circuit would shut off. I saw that the battery started drawing more than 5amps and my guess is that it shut itself down. I ran the circuit in this setup and it lasted.....30 minutes :/
I noticed that the Boost converter was getting quite hot and I wonder if this is where there is great energy loss.
I also happen to own this NPF powered 176 LED light and I've found that it draws 1.5 amps from the battery and powered the LED's which are set up in two parallel sets with a total of only 5.8V without any resistors. The light claims to output 1320 lumens and while it is indeed quite bright, is about 3 times dimmer than the theoretical output of my strip. However when I let it run on full power using the exact same 8000mA NPF battery it lasted 330 minutes! This suggests to me two things:
1. That my NPF battery is actually close to 8000mA capacity because with a 1.5A draw it would be calcluated to last 320 minutes (8Ah/1.5A=5.3hrs x 60minutes).
2. Therefore my setup definitely has some serious inefficiencies.
I tried running my setup at slightly lower voltage/current of 21V 1A and it lasted 90minutes which is certainly better but again the Booster gets hot and not very close to the calculated 140 minutes I could theoretically get with these settings.
It seems that the makers of the 176 LED light I purchased were smart in deciding to setup the LED's in an array that requires LESS voltage than the batteries native output and therefore only requires a slight step-down rather than a large boost. Do you think this could be where my efficiency is lost? I can't find any sub 9v LED strips, and while I've done a fair amount of research I don't exactly see why not.
Sorry for my long and probably rather uneducated post and thanks for any help!
I've been experimenting with these 2835 LED strips. I have cut it to 1 metre which has 240 LED's and to my understanding wants 24v and apx 1.5amps or 36W (180WattsPer5meters/5=36/24v=1.5a). I chose these because they seem to be the most efficient LED's out there and are low heat (which I assume is related to efficiency)
This NPF battery claims to have 8000mAh and while that's probably a vast exaggeration, in my understanding there should be enough juice to power these lights at full power for somewhere between 1-1.5 hrs. (8amps X 8v = 64Wh). Now I've also read that these NPF batteries have a max 5A discharge auto cutoff which is just above my calculated needs.
I've been using this Boost Converter to adjust output current/voltage which is rated for somewhere between 35-50W. I rigged it all up and adjusted the voltage to 24 and connect the LED with a low current. This low current kept the starting voltage below turning on point. As I raised the current I eventually got to 23 volts and 1.5 amps output and a very bright light strip. Any higher and the circuit would shut off. I saw that the battery started drawing more than 5amps and my guess is that it shut itself down. I ran the circuit in this setup and it lasted.....30 minutes :/
I noticed that the Boost converter was getting quite hot and I wonder if this is where there is great energy loss.
I also happen to own this NPF powered 176 LED light and I've found that it draws 1.5 amps from the battery and powered the LED's which are set up in two parallel sets with a total of only 5.8V without any resistors. The light claims to output 1320 lumens and while it is indeed quite bright, is about 3 times dimmer than the theoretical output of my strip. However when I let it run on full power using the exact same 8000mA NPF battery it lasted 330 minutes! This suggests to me two things:
1. That my NPF battery is actually close to 8000mA capacity because with a 1.5A draw it would be calcluated to last 320 minutes (8Ah/1.5A=5.3hrs x 60minutes).
2. Therefore my setup definitely has some serious inefficiencies.
I tried running my setup at slightly lower voltage/current of 21V 1A and it lasted 90minutes which is certainly better but again the Booster gets hot and not very close to the calculated 140 minutes I could theoretically get with these settings.
It seems that the makers of the 176 LED light I purchased were smart in deciding to setup the LED's in an array that requires LESS voltage than the batteries native output and therefore only requires a slight step-down rather than a large boost. Do you think this could be where my efficiency is lost? I can't find any sub 9v LED strips, and while I've done a fair amount of research I don't exactly see why not.
Sorry for my long and probably rather uneducated post and thanks for any help!
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