Hi people, I thought I would test the battery of my torch tonight, it lasted for 3 and a half hours on mid mode. I opened it up as this is not possible, and can only see 2 7135’s and ‘1050’ is typed there. Now, it is bright enough for me, and I am actually happy the battery lasts this long due to it being 1050, but I ordered the 2100MAH torch, not the 1050.
I will go onto fastech and order a 2100MAH from there, although this will still get use. Just dissapointed.
I have ordered the correct torch from fast tech, As I did want the 2100MAH model. It was less than ten pounds, and I selected the model from a drop down menu.
This light is still very bright though, so it wont get relegated to the bin, it will be my long lasting torch :).
Oh for gods sake, I didnt realise I hat to unsolder it then remove it. Four more chips on the bottom. It is the 2100MAH model. Oh well, I will have a spare.
You found it was 2100mAh after all, but I wanted to correct your other wrong idea here too about runtime: 2100mAh*40% (mid mode)=840mA(perhour)*3.5hrs observed above=2940mAh used from the battery…which is pretty standard, especially since these are rough numbers assuming there are no losses (there are), so it actually used more than 2940mAh from your battery, just a rough estimate without knowing your standard losses. You probably have a 3100mAh battery fully charged that you ran down is the closest approximation.
I am using samsung 25R’s, 2500MAH, which Is why I thought it was also lower powered, I worked out half power of 2100 to be 1050mah- 1050x 2 is 2100, so I expected about two and a half hours, not 3 and a half. I double checked I wasn’t accidentally on low, but was definitely on mid.
Luckily it all works after putting back together, I will resolder the joints tommorow but they are connecting fine and working at the moment.
Even more impressed now I know I get at least 3 hours from a battery, I was expecting an hour and a half and that was from a 3100MAH cell, so am now happy I know it is the correct model, My mum said she will have the one I just ordered so all sorted.
Sorry, I’m slapping my forehead now, as voltage drops, it drains less power (which is why you can note some dimming), so usually you want to also add a very rough (note, unscientific) –15% to –20%, so the number we had before doing this last part was 2940, so 2940 *(between .85 and .8) = 2499-2352mAh predicted mAh cell usage.
I’m going to use my ADHD excuse of doing reports with occasional distracted browsing as my error Its only a rough estimate calculation to see if its approximately within range that I’ve found works pretty nicely as I don’t have the time to test batteries or the equipment. There are many factors like driver wastage of mAh, true battery mAh is always different in each battery from stated mAh, and some drivers up the voltage so you dont have the losses, etc. I just use it to see if its approximately around expected, which yours is very much in range. Maybe even better than expected, and/or you didn’t run the battery all the way down to 3.7V (which you shouldn’t really do a lot).
Medium is not half power usually, its usually 40%.
But, they are genuine 25R’s from a respected shop. Thank you for correcting me, I thought it was 50% I didn’t realise 40%. But one of my main reasons for thinking it was the lower powered torch was this using up 2940MAH thing, by my calculations it should of died sooner, by yours it should of too.
I waited for the low power blinking light to come on. How can this be possible? I double checked it was on Mid, and just sat it pointing at the wall checking every couple of minutes. The battery should be 2500MAH, with high amp draw, now I don’t know the ins and outs of electricity, but I wonder as the battery was rated for high drain applications, the low amp draw of a torch was easy on it? But 3 and a half hours from 4.2 volts to 3.1-2.9? I’m not sure how that works.
ANd lol at the comments I will have lots of spares in a month from now, you are probably correct unfortuneately lol (But better than booze. I had a big drink problem, so my family is happy me spending my money on anything that interests me and won’t slowly kill me like the booze, I was basicallly at the walking dead stage, just waiting to go. Luckily my mum phoned an amubulance as I couldnt even get out of bed for 2 weeks, it was just drink to try keep well, be sick, then sleep. I detoxed in hospital but had a bad seizure from lack of alcohol which left some lasting damage, but I feel so much better without a bottle and a half of vodka in me a day. I thought I had been here long enough I might as well tell you my little story).
So, any ideas on how it lasted that long would be great, this was the second battery I purchased(I numbered them so I know if I get a bad one which one it was, in a set of 2, so far I have Numbers 1,2 and 3, as I was living on one battery till I got my torches, although know other good brands through the other community of vaping, I really want some of them LG 3000MAH 20 amp monsters.).
ANd thanks for the warning on not running the batteries too low, I was aware through my other hobby but I may not of known that being new to flashlights. You are a good bunch here, and I quite like it if I am honest :).
This is the toughest part about flashlights for me.
But from what I understand, toward the end of the battery’s capacity (lower voltage) the current requested by the driver can no longer be supplied so it instead supplies as much as it can (Direct drive) thus offering less and less light output and extending the runtime. Under load I believe the Nanjg drivers start blinking low voltage warning at ~2.85v.
7135 chips are regulated, which means that they will not allow more current to flow than the amount of chips used. BUT, if you’re using 2100 mA and the cell drops below that, then it will drop out of regulation and continue emitting at lesser and lesser amounts until, yep, the driver blinks and steps down and then eventually shuts off completely.
I don’t have very many true Nanjg 105C drivers as I was into the Qlite, but those used 2,15,30% and 100%. I guess the point is that different drivers use a different percentage for the levels.
I haven’t used those for quite a while now, I’ve pretty much gone all out FET driver in everything I do. (I DO have a little bag full of drivers I’ve yanked out of lights though, lol)