parasitic drain convoy lit switch, did anyone mesure it?

I'm planing to buy two Convoy M21B GT-FC40 4000-4500K (I understand that all tint have high CRI).
And I'm wondering if to buy the lit switch to it, mainly by how high is the parasitic drain is. Did anyone mesure it?
I will use two of them on bike in the wild, for city I have two lumintop B01, and mactronic scream superior, so don't worry.

Ps. Is the metal lit switch worth it, or to just go with the translucent/white lit switch?

https://aliexpress.com/item/1005003457987060.html <- translucent/white lit switch
https://aliexpress.com/item/1005002389032527.html < - metal lit switch

Pps. It is compatible with Convoy M21B GT-FC40 12 Group, right?

The last blue lighted switch that I installed in a flashlight from the Convoy flashlight Store draws 0.17 milliamps at 4.1 volts. Blue LEDs are pretty efficient.

any info on the orange one?

Can you share how your measurement setup is done? Maybe a simple picture would help, I’ll try to measure mine.

OK did my measurements on 2 blue lit switches on 2 Convoy M21B GT-FC40

it's around 750-890µA depending how I swap the 2 of them.

To measure it, You just take out the tube, and insert probes where the tube would contact the head and the tail. (do you need pictures how to measure it, or is this clear enough?)

Sorry I missed these questions last year. :person_facepalming:

I just connect a wire from the positive post of the battery to the positive post/spring of the driver. And then just touch the DMM leads from the body threads to the driver retaining ring (or head threads).

For orange (and red), I measure 0.48mA. That’s the highest I will go with my tailcaps.

kokosnh, 0.75-0.89mA must be very bright for blue LEDs! Different drivers will have different results with how bright the LEDs are with the stock lighted tailcaps. Have you thought about lowering the brightness by changing the resistors?

It's bright.
It should take around half a year to drain the samsung 21700 40T that's in it, so for now I won't be lowering it.
The main purpose of this light is, as bike off road lights, so having it shine bright is not a problem.
I just have to know that for longer storage, to unscrew the tail to physically lockout the flashlight.
But parasitic drain it's not high enough, to unscrew it all the time, only for winter if needed.

Sounds good kokosnh. :+1:

0.48mA is not for the stock Convoy orange lit tailcap. I measured 2.8mA with the battery at 4.0V. I replaced the 330 Ohm resistors with 5.1k Ohm resistors which makes it bright enough to find in the dark and with 0.250mA at 4V (lower at lower voltages) will likely drain the battery in 600 days or more. That’s how they should be sold, even if not so bright, otherwise in 2 months it will drain your 18650.

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I’m not surprised that you measured 2.8mA since they come very bright stock. :sunglasses:

All of my lighted switches are modified to the brightness that I prefer. I also tune them to have very similar brightness. The inefficient orange and red are in 21700 flashlights due to the extra capacity (1.2 years).

And depending on the driver, different resistance is needed for the same brightness. Some drivers (like the Convoy SST40 drivers) also have much more of a change in brightness depending on the voltage than others. That can be used like a voltage indicator. The overall expected longevity increases too since the brightness decreases significantly as the battery depletes.

I agree they shouldn’t be sold being so bright. But maybe they’re sold more as a novelty than as a legitimate flashlight option. Regardless, my minimum is 1 year with a lighted switch and most of them last much much longer.

Very interesting discussion. You guys obviously are obviously more “advanced”/skillful than I am. :+1:

FWIW, for anyone new to this, stock blue Convoy metal switch measures 1 mA with full charged battery and down to 0.7 mA at lower voltage around 4v. If you are not modding the switch by adding resistor, blue has less parasitic drain than orange and for that reason the “better” choice.

For me, the metal switch is a must-have for my S21D (w/ Nichia 219b and 519a) and M21B (w/ Nichia wannabe, and be, GTFC-40), for both ergonomic and cosmetic reason.

How about the new green, red and RGB switches? When you include all those, which one has the lowest drain without modding?

No idea about the RGB one [ I mean about the exact drain ], but as all of the others they will drain the battery too quickly.

I modified the 2nd orange lit tail switch with 10k resistors. Current 0.102 mA at 4.15V. Bright enough and bright enough too with a battery at 3.3V. This will last more than 4 years, with 5k resistors I estimate 1.7 years. Both are fine w.r.t. brightness, visible in daytime (better than the orange button lights of the D4V2) and easily in the dark.

It’s not difficult, if you have a soldering station with a few different tips (KSGER T12 for example) you can easily try yourself.

That’s a mod I’m interested in doing, but I don’t have very steady hands for such small parts. Even normal reflow is already testing my limits for soldering. Thanks for the info!

Green should be the lowest drain assuming they all come with similar brightness.

For my lighted switches, green runs around 0.07mA and red is around 0.46mA. So the green is around 6 times more efficient. It’s amazing how much more efficient the green LEDs are compared to the other colors.

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Fantastic information, thanks