s7e7v7e7n7
Posts: 8
Joined: Fri Sep 29, 2017 7:14 pm

Re: 3W 850nm leds working voltage?

Thu Oct 05, 2017 11:11 am

KLL wrote:
Mon Oct 02, 2017 7:37 am
could you check the mA / LED
i buy one multimeter.

Image

It looks like 1.4 amps. But i'm not sure I made the right measurements.

what do you think?

s7e7v7e7n7
Posts: 8
Joined: Fri Sep 29, 2017 7:14 pm

Re: 3W 850nm leds working voltage?

Thu Oct 05, 2017 11:14 am

mahjongg wrote:
Wed Oct 04, 2017 12:44 pm
s7e7v7e7n7 wrote:
Mon Oct 02, 2017 7:31 am
Here is my raspberry + case + leds noir camera
Image
I'm not sure you have wired it correctly, it could be that only one of the LED's is actually burning, if the arrows are pointing to where you connect the positive wires, then at least one of them seems wired the wrong way around.

this picture shows how to connect power to the two modules.
Two IR LED modules.gif

Best use an EXTERNAL 3.3Volt power supply, using the internal 3.3V of the PI might result in either very dim LED's or overloading of the 3.3V supply. Using an external supply you can turn up the brightness without endangering your PI.

Perhaps its also possible to feed these LED's 5V, but then they might get very hot, and also the transistors that limit the current might, to the point they burn up, as they would dissipate at least as much power as the LED's do..
Hello, actually I tied you in the way you said. I did not mark the picture because the other ends were in the back.

but i connect to wires 3.3v and gnd both of them. Thanks.

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PeterO
Posts: 4539
Joined: Sun Jul 22, 2012 4:14 pm

Re: 3W 850nm leds working voltage?

Thu Oct 05, 2017 11:25 am

s7e7v7e7n7 wrote:
Thu Oct 05, 2017 11:11 am
KLL wrote:
Mon Oct 02, 2017 7:37 am
could you check the mA / LED
i buy one multimeter.

Image

It looks like 1.4 amps. But i'm not sure I made the right measurements.

what do you think?
I think you need to learn how to use a multimeter before you damage something.
It looks like you have effectively short circuited the 3.3V supply.
To measure current you have to break into the circuit...

This looks like a goof tutorial for you to follow : https://learn.sparkfun.com/tutorials/ho ... multimeter

PeterO
Discoverer of the PI2 XENON DEATH FLASH!
Interests: C,Python,PIC,Electronics,Ham Radio (G0DZB),1960s British Computers.
"The primary requirement (as we've always seen in your examples) is that the code is readable. " Dougie Lawson

s7e7v7e7n7
Posts: 8
Joined: Fri Sep 29, 2017 7:14 pm

Re: 3W 850nm leds working voltage?

Thu Oct 05, 2017 12:41 pm

PeterO wrote:
Thu Oct 05, 2017 11:25 am
s7e7v7e7n7 wrote:
Thu Oct 05, 2017 11:11 am
KLL wrote:
Mon Oct 02, 2017 7:37 am
could you check the mA / LED
i buy one multimeter.

Image

It looks like 1.4 amps. But i'm not sure I made the right measurements.

what do you think?
I think you need to learn how to use a multimeter before you damage something.
It looks like you have effectively short circuited the 3.3V supply.
To measure current you have to break into the circuit...

This looks like a goof tutorial for you to follow : https://learn.sparkfun.com/tutorials/ho ... multimeter

PeterO
Yes Peter. Good point :shock: I dont know using to multimeter. Thanks for links...

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Re: 3W 850nm leds working voltage?

Thu Oct 05, 2017 4:54 pm

mahjongg wrote:
Wed Oct 04, 2017 12:44 pm
...I'm not sure you have wired it correctly, it could be that only one of the LED's is actually burning, ...
if you only want to know, if both IR LED's are working, simply use the smart-/mobile-/cell- phones camera, and watch the LEDs when they are powered up.
many/(most?)/(all?) cameras on a (cheap?) smart-/mobile-/cell- phone are sensitive enough to IR to see if IR LEDs are working or not.
i always check my TVs and others IR remotecontrol like this, to see if the RC is working or not.

if you do not have a smart-/mobile-/cell- phone with a camera, use your IR camera + 2x IR LED + RPi construction and a mirror - and take a picture of itself. then you can see if both IR LEDs are working.

PS.: the night photo shown some posts ealier, what is wrong with it?
too dimmed?
what do you expect how bright it shold be?
{ I only give negative feedback }
RPi Model B (rev1, 256MB) & B (rev2, 512MB) & B+, RPi2B (1GB), 64GB microSDXC1 class 10, HDMI 1920x1080, keyboard-mouse-combo (wireless), PiCamera, ethernet-cable, 5V/1.2A power supply, Wifi dongle (rt5370)

nick8967
Posts: 61
Joined: Fri Mar 25, 2016 11:02 pm

Re: 3W 850nm leds working voltage?

Thu May 31, 2018 2:37 pm

Because these IR LEDs demand a lot of current, I want to supply them with different power supply. Can I disconnect them from the camera and supply them or they need to be attached to the camera module for some reason that I miss right know?

nick8967
Posts: 61
Joined: Fri Mar 25, 2016 11:02 pm

Re: 3W 850nm leds working voltage?

Thu May 31, 2018 10:52 pm

Someone??

darkaural
Posts: 1
Joined: Mon Sep 10, 2018 10:09 pm

Re: 3W 850nm leds working voltage?

Mon Sep 10, 2018 10:26 pm

Hello guys

I've got the ( exact?) same camera and led thingies as the subject of this thread, bought them from ebay and after a bit digging around the web searching for IR safety I came around thease findings
1;) seems like https://www.waveshare.com was the one which came with the original design ( altough the possibility is that many chinese manufacturers have copied it, changed it, modified it, changed the leds etc... )
2;) I have only 1 led connected. I simply do not need more ( and as mentioned I am a bit worried about IR harm ) The led requires 3.3 volts ( actually measured it, 3,2 volts is on the terminals ). This thing has a potentiometer, when fully drilled DOWN it eats around 120mA, have not taken a measurement when fully up but rest assured my PI handles it well
3;) I have a standard setup of a RBPI 3+ with the official rbpi power supply and have no problems whatsoever. i'm using the original ribbon cable what came with the cam to power both the cam and the 1 led

this thing is actually pretty straightforward...if it lights up dimly red it is on


now to the question if you can power it externally: simple answer is: yes you can, just make sure you give it 3.3 volts, than the supply can handle an amp or two ( depends if you want them both or just one and how high are you willing to drive them)

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ragnarjensen
Posts: 331
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Location: Stockholm, Sweden
Contact: Website

Re: 3W 850nm leds working voltage?

Mon Sep 17, 2018 6:36 pm

I have a bunch of these LEDs. I use them to give some surveillance cameras night vision. They are 1W, pulling about 350 mA when going full tilt.

The potentiometer does not adjust the brightness, it is used to adjust the sensitivity of the light sensor (how dark it should be for the LED to turn on). The light sensor circuit adjusts the current to the LED quite slowly, it takes a couple of minutes in complete darkness to reach full brightness.

Edit to add:
They can get real hot, I have killed a couple by being sloppy with the mounting - in small cases without airflow.



--
Ragnar
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