Well I am not a new user…but I have a question. I am in the process of testing a small power station/power bank. I got one of these Atorch load testers. The unit is rated at ~153 Wh/12Ah. When I test the PD output at 20 volts and 3 Amps I get 6551 mAh and 127.2 Wh out. (55% /83% of rated). Using the 12 volt dc output (constant current 4.5 amps) I see 11,125 mAh and 138.4 Wh. (93%/90% of rated). Can anyone tell me why this could be. My methodology perhaps? I know there is always conversion losses. But the manufacturer tells me both outputs should be better than 90%.
I am particularly suspicious of the PD mAh numbers.
DC
PD
mAh is capacity at a particular voltage. The “Ene” expressed in Wh is not dependent on voltage, it basically shows the total amount of energy available and those values are pretty similar for both protocols, a bit less for the higher power as is expected as this translates to higher amperage from the cell.
Yep. Those 12Ah is a capacity of the battery which is, apparently, LiFePO4 4S so has nominal voltage of 12.8V (12.8V x 12Ah = 153.6Wh).
Unless your station has a direct battery output terminals (XT60 e.g.) there is no point in measuring capacity. So compare only energy.
Why the measured energy amounts are much lower than declared ? … I dunno.
Maybe converter is very inefficient (for DC-DC converter this is unlikely). Maybe BMS cuts output too early. Or maybe battery has lower capacity than stated.
Thanks. The real question is why the PD output is measuring so much lower than the 12 volt output. Even using Watt hours. Certainly there is some voltage conversion inefficiency going on. Which would be greater for the PD output. As I think the 12 volt output is almost a straight through process. But the difference in the two measurements is way more than I expected. IOW if we use Watt hour it is basically volts X Current over time. So that number corrected for conversion losses should, in theory, match up pretty well. They are not that close. But there is an even bigger difference in the mAh numbers?
Crazy assumption: there’s a buck-boost converter, so double conversion is applied in case of 20V output.
Also to gain more food for thought you can run 12V and 20V tests at lower currents. If you have lot of time 
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Thanks. Just trying to understand the differences in the numbers. I did use 60 Watt draw (or pretty close) for both tests. The total time to shut down is not that different. I got a 12% difference in the total discharge time and over 40% difference in the mAh numbers. Only about a 8% difference in the Wh numbers. There is something going on that I don’t understand.
I may try the tests at a lower draw, but you are right, it will probably mean another 8+ hours of testing.
I recall reading a post (somewhere) warning that Convoy programmable drivers are susceptible to overloading the chip memory and bricking the driver if the light is left in programming sequence for too long. Is this really a concern?
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Just making sure I’m not hallucinating…
Anyone remember the brief namechange from Convoy to something like “Convay”, with a hideous new logo, that was Not Well Received and then changed back to the Convoy we all know and love?
Is there a source of pills for S2+ with rectangular threads?
These from KD should be rectangular threads: K12 FLASHLIGHT BRASS DRIVER PILLAR SET 21.8MM (D) X 13MM (H)
Thank you. I am concerned that pillar has the same description (Thread Spacing) as this one, which clearly has triangular threads according to photo. Oddly both pills are stated to have same weight.
Do you think descriptions and/or photos might be inaccurate ?
I’m glad I got all my shiite from Simon and/or Fasttech back when only the old S2+ was around with the old threads on head/tail/tube, and pills. Probably retaining rings as well.
I can’t imagine getting right both the diameter and pitch, only to find that one’s triangular and the other square or trapezoidal.
Or LH vs RH.
My head hurts…
Oh, C8s, too.
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Agree about the C8. It puts out enough light that I wonder what you guys need with more. I can see wanting something smaller or with a longer lasting battery though.
I got these cheep cheep cheep crappy C8 clones with thin Al pills, and the beefier brass ones from Fasttech fit perfectly, threadwise. Just barely enough headroom, so you had to snug down everything pretty tightly to get everything to fit, but it did.
One of my faves was a 4000K XP-E2 with 1.05A driver, I think. With a 3400mAH panny-B, that would go for at least 3hrs straight throwing a nice tight pencil-beam that had decent reach for such a little donk.
Still got it somewhere, too.
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People used to tell me they thought I was on a motorcycle or driving a car when I used my C8 with another light that put out less power. And I usually ran the C8 on the medium setting. That gave me plenty of flood with enough intensity to attract the attention of drivers intently staring at their phones instead of watching where they were going.
anyidea were to get some pills for those clones?
or do you think the ones from KD will fit?
Before you put a lot of effort in search for a pill, check if your C8’s are the ones with a pill or with a shelf.
No idea in the slightest.
The one i got has a pill the rest are still in transit, anyway ordered all 3 types from KD lets hope the ones that has stock fit
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