LF P7 M series Turbo Head questions

Below is a copy of an email I have sent to Lumens Factory.

Can anyone here answer the questions I have?

"Hello,


I received my new P7 M series turbo head*today*and it looks great on my Surefire M4.


I have a few questions. *I searched your website but could not find the answers.


1. Can you explain "constant output" to me? Basically how will the light operate when the batteries start to get low?*


2. I have the 3 output mode version. *Is the light supposed to flash bright for a fraction of a second when I turn it on? *For instance, *if I have it in 5% mode, *when I first turn it on it flashes full power for a faction of a second then goes to 5%. Normal? *


Thanks."

1. You will get almost constant *ie the same level of output for a certain amount of time. The length of this constant output will be determined by the type and number of batteries you use in the flash light.
After the batteries have been depleted to a certain point then the output will drop off. Again the speed at which this drop off occurs, and how long it will last in this reduced output will be determined by the type and number of batteries you use.
For example *my own experience with the single speed P7 head. Using 2 x AW17500 cells I get about 30 minutes max at a constant brightness.....after this the output drops significantly for a while...never really tested per say.....then the light will cut out completely.

When using 3 x cr123 primaries the max brightness will last for longer, almost 1 hour before the output drops off. With primary cells the light will run at this reduced output far longer than it will on the 17500 cells.

2. This is known as a *pre-flash*. Many multi mode lights do this. While some people do not like it, don't worry about it, your light is not defective. It is simply a characteristic of some particular multimode drivers.

I believe primaries are the best way to run a light but they become expensive so you definately should consider a rechargable option for this type of light.
If your M4 body is bored - go with the latest and best capacity 18650 rechargable some of the good ones are now 2900mah to 3000mah.
If your M4 body is not modified or you do not want to modify it *as I didnt* then a great option is the Redilast brand of 17670 batteries. They are rated at 2000mah. I use these cells in my surefires. You would need 2 cells for your M4. These should give you 1 to 1.5 hrs runtime give or take a few minutes. EDC Plus sell these cells.

Thanks so much Rat. Answered all my questions.

Should you receive a reply check rule 12 before posting it here.

Norm