i got a surefire 3p in the mail and want to put a p60 drop in that draws 2.1 amps on high. so i know i can run an imr 16350 but can i use also use primary 123's. they are battery station cr123 1550 mAh. the way i figure with a safe discharge of 2c i can run up to 3 amps. is this correct?
cr123 discharge rate?
- Thread starter gianetics
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LilKevin715
Enlightened
What kind of dropin (and driver) are you using? Irreguardless of driver type the max continuous discharge rate of a primary CR123 is 1C.
its a p60 xp-g2 modified by vinh. i got it on the mp here http://www.cpfmarketplace.com/mp/showthread.php?288123-SOLD-XP-G2-2-1A-P60-Dropin-(Vinh) so what your saying is that primary 123s have a discharge rate of 1c. well that sucks ive got to buy imr cells. i understand the dangers of litiums at 1550 mAh 2.1a is drawing 1/2 amp over 1c how much of a concern is this?
LilKevin715
Enlightened
It's not recommended to exceed the 1C continuous discharge rate as the cell will heat up more, which can lead to the cell possibly exploding:poof:.
The driver on your dropin is based on AMC7135 linear regulators (search CPF for more info). AMC7135 linear regulators will maintain the rated output as long as the Vin (battery) requirements are met. The Vin requirements are the Vf of the LED + 0.12v overhead + host resistance. A single CR123 primary under load is roughly around 2.5v or less (depending on load), which is well under the requirements. Taking this into account the output on a single CR123 primary is probably going to be pretty dim (if it works at all). Since this is the case you will not get the full 2.1A output with a single CR123 primary.
A li-ion cell (LiCo, IMR) is better suited as their voltage under load will be higher. If you want to run the light on a single CR123 primary you need a boost driver.
The driver on your dropin is based on AMC7135 linear regulators (search CPF for more info). AMC7135 linear regulators will maintain the rated output as long as the Vin (battery) requirements are met. The Vin requirements are the Vf of the LED + 0.12v overhead + host resistance. A single CR123 primary under load is roughly around 2.5v or less (depending on load), which is well under the requirements. Taking this into account the output on a single CR123 primary is probably going to be pretty dim (if it works at all). Since this is the case you will not get the full 2.1A output with a single CR123 primary.
A li-ion cell (LiCo, IMR) is better suited as their voltage under load will be higher. If you want to run the light on a single CR123 primary you need a boost driver.
Kestrel
Flashaholic
That dropin does not have the low-voltage driver, so it will probably run poorly if at all on an single non-rechargeable CR123 primary.
With regards to rechargeable cells, an IMR123 is your best best, as a LiCo RCR123 would run at ~4C if that module does run @ 2.1A.
With regards to rechargeable cells, an IMR123 is your best best, as a LiCo RCR123 would run at ~4C if that module does run @ 2.1A.
