jon_slider
Flashlight Enthusiast
- Joined
- Mar 31, 2015
- Messages
- 5,393
My HDS rotary only works on rechargeables and not primaries.
Here is the fastest way to teach your HDS that you want it to use CR123:
1. With the LiIon inside, clic the light ON.
2. Remove the head, remove the LiIon, Install a CR123
3. Reinstall the head. The light will turn on for 7 seconds and then will turn off. Do Nothing until it turns itself Off.
or, here is the simplest way to teach your HDS to use CR123
1. Starting with the light OFF, remove the head, and wait 1 minute (or longer) before reclosing the light w a CR123 inside.
2. Reinstall the head. The light will turn on for 7 seconds and then will turn off. Do Nothing until it turns itself Off.
Now you can use the light with CR123. You can replace the CR123 with another CR123, as many times as you like. As long as you do not install a LiIon, it will continue to work w CR123.
IF you install a LiIon, it will forget you want to use CR123, and the next time you decide to go back to CR123, you have to follow either the fastest or simplest steps above.
backstory
LiIon has a higher voltage (over 4V fully charged), than CR123 (3.3V max).. IF the HDS senses LiIon Voltage (above 3.3V), the light enables Low Voltage Protection (LVP), that turns the light off at 3Volts, to prevent overdischarging the LiIon.
If a CR123 is swapped in to replace the LiIon (without the head being removed for 1 minute or more, or without following the first group of steps 1-3 above), the light will assume the new battery is still a LiIon. Therefore LVP remains active and it will shut the light off when the CR123 battery gets to 3V.
That is the reason your light is not working w CR123.
otoh, IF the HDS learns that we want to use CR123, the light will disable LVP. This allows the light to drain the CR123 below 3V.
The next time a LiIon is inserted, the HDS enables LVP automatically, and then the light wont work w CR123 after that.
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HDS potential pitfall that could defeat LVP and cause overdischarge of a LiIon
IF an HDS battery gets low enough to trigger LVP at 3V and the light turns off
and
IF the operator opens the light, and waits 1 minute or more to reclose it, the LiIon could be overdischarged
IF the battery is below 3.3V
because, the HDS battery detection would see less than 3.3V, and would disable LVP, because it assumes the battery is a Primary CR123, instead of a LiIon.
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