Are the heads of the P2D and P3D the same?

I wanted to buy a new P2D with Q5 and now I wanted to ask if the heads of the P2D and the P3D are the same. I'm asking this because on the Fenixstore site it's recommended not to use the AW's RCR123A 750mah for the P2D but it's ok to use it with the P3D. So is there any difference except the longer battery tube?

rayman

No, they are not the same. The P2D head is the same as the L1D/L2D. The P3D has a buck only circuit, where the P2D is boost only.

Marduke said:

No, they are not the same. The P2D head is the same as the L1D/L2D. The P3D has a buck only circuit, where the P2D is boost only.

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OK I'm sorry what does buck only and boost only circuit mean?
So can I use the P3D head with the P2D battery tube and tailscape with 16340 750mAh AW Protected and still can use all modes?

rayman

Buck only means your battery has to be above 3.6V, The circuit then limits the current to the correct value.
Boost only means your battery has to be below 3.4V. An amplifier in the circuit brings the voltage up to the correct level.

rayman said:

OK I'm sorry what does buck only and boost only circuit mean?

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Yes

rayman said:

So can I use the P3D head with the P2D battery tube and tailscape with 16340 750mAh AW Protected and still can use all modes?

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All the modes will work with a fully charged RCR123 for a short period of time. Depending on the Vf(forward voltage) of your particular LED, turbo will start giving you the low voltage warning(rapid flashing) pretty quick.

The P3D has been tested up to 16v by David(4-7s) at the Fenix-Store and works best with at least 2 CR123s or 2 RCR123s(you can get a 3 CR123 accessory tube for the P3D).

On my P3D I get the low voltage warning at 20 minutes or less with a 17670(~1500 mah).

Sorta on the same subject... has anyone tried a P3D head on an L2D body with 2 14500's? Is it a worthwhile mod? Or not much different than two 16340's. :shrug:

Lite_me said:

Sorta on the same subject... has anyone tried a P3D head on an L2D body with 2 14500's? Is it a worthwhile mod? Or not much different than two 16340's. :shrug:

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The 14500 & 16340 have about the same capacity (~700mAh) so it is not worth it.

LEDninja said:

Buck only means your battery has to be above 3.6V, The circuit then limits the current to the correct value.
Boost only means your battery has to be below 3.4V. An amplifier in the circuit brings the voltage up to the correct level.

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So do I understand it right. If I use a P3D head, with buck only, with a P2D battery tube and tailcape the runtime is much shorter than with the normal P2D head?

rayman

Yes because it doesn't boost the voltage to the Vf of the LED.
First you lose turbo, then high and so on.
It was really made for an input voltage of at least 6.0v(2 CR123s).

So now I did my decision. I will buy the Fenix 4in1 Powerpack .

rayman

LEDninja said:

The 14500 & 16340 have about the same capacity (~700mAh) so it is not worth it.

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I tried (2) 14500 on a P2D head with the 2AA tube. It went a dim purple as soon as I turned it on and now the Turbo mode does not work. Yes it was an accident. I was also handling and charging Eneloops at the time and was not paying attention to what I was doing.

The moral of the story is they are two completely different heads.

Bill

Hitthespot said:

I tried (2) 14500 on a P2D head with the 2AA tube. It went a dim purple as soon as I turned it on and now the Turbo mode does not work. Yes it was an accident. I was also handling and charging Eneloops at the time and was not paying attention to what I was doing.

The moral of the story is they are two completely different heads.

Bill

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I'm sorry for you. I first thought it's only one head and only the battery tubes and the tailcapes are different :sigh:.

rayman

Hitthespot said:

I tried (2) 14500 on a P2D head with the 2AA tube. It went a dim purple as soon as I turned it on and now the Turbo mode does not work. Yes it was an accident. I was also handling and charging Eneloops at the time and was not paying attention to what I was doing.

The moral of the story is they are two completely different heads.

Bill

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Yup! I've got to watch that too cause I'm using a P2D head on a an L2D body also. Come to think of it, it doesn't matter if it's an L2D head either cause they're the same. You gotta watch it and not put 2 14500's in there. I'm safe right now cause I only have 2 14500's and 1 is always in another light. But, I'm getting ready to order some more for other stuff.