Welcome to Laser Pointer Forums! If you are looking for a laser you may want to check out the database of laser pointer companies. The link will open in a new window for your convenience.

 Laser Pointer Forums - Discuss Laser Pointers Quick question... Laser Pointer Company Database     Laser Top Sites List     Lasers by Type     Green Lasers

09-28-2009, 01:48 AM #1
 Class 2M Laser Join Date: Aug 2009 Posts: 690 Rep Power: 20
Tabish
Class 2M Laser

Join Date: Aug 2009
Posts: 690
Rep Power: 20
Quick question...

If I power a PHR / rkcstr driver (set at 100ma) using 2x 10440 batts (from dx).

How long before the voltage drops to where its too low for the rkcstr.

My guess:

Fully charged = 4.2 x 2 = 8.4v

phr @ 100ma uses 4.5v ??? add 2.25v the driver burns up

4.5 + 2.25 = 6.75v

8.4 - 6.75 = 1.65 (max voltage drop allowed before voltage is too low)

8.4 - 1.65 = 6.75v (lowest i should let the voltage for both bats hit)

That means 3.375 V per cell

SO BASICALLY:

The draw is 100ma. The battery is just over 300ma. (trustfire rates at 600)

How long before a 4.2v cell drops to 3.375v at that current draw and battery capacity?

Just curious because I want to put it inside jayrobs pen host but I was told 2 10440's cannot power a phr / rkcstr.

I don't mind if it runs 5min. So long as it RUNS AT ALL.

__________________
30mW Green
200mW Red
445nm A-140 1W

09-28-2009, 02:03 AM #2
 Class 3B Laser Join Date: Feb 2008 Posts: 2,830 Rep Power: 242
ndrew2505
Class 3B Laser

Join Date: Feb 2008
Posts: 2,830
Rep Power: 242
Re: Quick question...

cant tell you an exact time but it does take a while... if you have an lpm you can test it. the power will start to sag when the batteries get drained enough.

09-28-2009, 03:09 AM #3
 Class 4 Laser Join Date: Sep 2007 Location: Northern CA, U.S. Astrophotography! (Some of my Photos) Posts: 9,823 Rep Power: 887
jayrob
Class 4 Laser

Join Date: Sep 2007
Location: Northern CA, U.S. Astrophotography! (Some of my Photos)
Posts: 9,823
Rep Power: 887
Re: Quick question...

Yes, it will work... (at full charge)

But with a load on the batteries, the voltage immediately drops. As far as just how much, and for how long the driver will stay in regulation, will simply depend on the quality of the batteries. And the charger for that matter...

8x BR DIODES
__________________
Personal lasers:
(just a few - too many to list) RPL 425, Sypder III Krypton, RPL 35 (473), GLP-473, GLP-593.5, HeNe 632.8,
Many DIY 445, red, blu-ray, green, 635, and 450 builds...

Looking for a DIY kit?

Take a look at some of my more popular kits linked in color...

* FS: 405-G-1 Glass Lens Mod for Blu-ray! 31% increase in power vs AixiZ acrylic!

* FS: New! 1000 Lumen XML-2 Maglite Modification With Voltage Monitor! - Parts or Complete Light! Must see!

* FS: Polished Stainless Steel Green Kit! Easy assembly in minutes!

* FS: Large Maglite Monster Kits! Side Button Forward Clicky! Custom Head Option! Gnarly...

Click here for a list of my build kits! Projects and tutorials too!

09-28-2009, 04:27 AM #4
 Class 2M Laser Join Date: Aug 2009 Posts: 690 Rep Power: 20
Tabish
Class 2M Laser

Join Date: Aug 2009
Posts: 690
Rep Power: 20
Re: Quick question...

Ok. Thanks for the replies.

Jay,

Eventually I'll upgrade it it with a flexdrive and a 6x or 8x.
__________________
30mW Green
200mW Red
445nm A-140 1W

 Thread Tools Display Modes Linear Mode

 Posting Rules You may not post new threads You may not post replies You may not post attachments You may not edit your posts BB code is On Smilies are On [IMG] code is On HTML code is OffTrackbacks are On Pingbacks are On Refbacks are On Forum Rules

All times are GMT. The time now is 02:40 AM.

 -- DarkShadows V5 -- Responsive LPF -2562016 -- Default Style Contact Us - Laser Pointer Forums - Archive - Top