P7 - direct drive from 17670 possible?

[easilyled]

I've seen many say that the 18650 is ok for dd-ing the P7

Is this also possible for the 17670?

I have some lights that may be suitable for P7 replacement but
the cell-tubes are not wide enough for 18650s

 

[vinsanity286]

I would say that a 17670 is pushing it's limits driving a P7 directly. It would be beyond 1.5c which is known as the standard safe limit for these lithiums. That is not to say that you CANT do it, but make sure to be careful or

 

[TigerhawkT3]

They should be fine, as long as you're not overdriving the P7 too much. I'd recommend keeping the current under 3.5A or so.

 

[easilyled]

I would say that a 17670 is pushing it's limits driving a P7 directly. It would be beyond 1.5c which is known as the standard safe limit for these lithiums. That is not to say that you CANT do it, but make sure to be careful or

You mean there's a chance it could explode?

 

[easilyled]

They should be fine, as long as you're not overdriving the P7 too much. I'd recommend keeping the current under 3.5A or so.

Thanks, but if its in direct-drive surely there wouldn't be a way of
controlling what current goes to the led?

 

[StefanFS]

It should be no problem direct driving from one 17670 or 18650 LiION. Your only possible problem would be lack of regulation, if you like perfect regulation. I use direct drive in my Tiablo A8 with SSC P7 (with a two level tailcap) it's works good. I have tested some driver solutions, but I prefer direct drive with this led until some serious drivers comes along.

 

[easilyled]

It should be no problem direct driving from one 17670 or 18650 LiION. Your only possible problem would be lack of regulation, if you like perfect regulation. I use direct drive in my Tiablo A8 with SSC P7 (with a two level tailcap) it's works good. I have tested some driver solutions, but I prefer direct drive with this led until some serious drivers comes along.

Thanks, I presume this is with an 18650?

 

[StefanFS]

My A8 starts at ~2.9A and quickly settles around 2.7-2.8A. So I feel quite safe with direct driving it.

 

[vinsanity286]

Yea, sorry I should not have implied that the cell would blow up. It may get warm and reduce the life of the cell but otherwise should be no prob.

StefanFS, BEAMSHOTS BEAMSHOTS BEAMSHOTS! I would love to see how that mod was done and how much light it puts out compared to stock, and other lights you have. Did it reduce throw abit? Sorry to hijack your thread easilyled, just curious.

 

[StefanFS]

Yea, sorry I should not have implied that the cell would blow up. It may get warm and reduce the life of the cell but otherwise should be no prob.

StefanFS, BEAMSHOTS BEAMSHOTS BEAMSHOTS! I would love to see how that mod was done and how much light it puts out compared to stock, and other lights you have. Did it reduce throw abit? Sorry to hijack your thread easilyled, just curious.

I feel like an asshole! But I have to wait until this weekend to do beamshots. I did start a thread here in this subforum about my Tiablo A8. Yes, it does reduce throw in that reflector. It was expected. This is something else entirely, it's almost a wall of light. Imagine maybe ~900 emitter lumens from a 18650 size led light, through an UCL lens from a somewhat efficient reflector! It's nice.
Stefan

 

[TigerhawkT3]

If it's DD, there still is a way of controlling the current going through the LED. That would be a resistor. I think "DD" refers to pure direct drive, with absolutely nothing between the emitters(s) and battery, while a light that has a resistor limiting the current is called "resistored." So, you could just turn it from a DD light to a resistored light.

 

[simple]

From Stefan's result with a 18650, it should be safe to direct drive without a resistor with 17670.