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FrozenGate by Avery

FS: ***Selectable test load up to 3A (assembled or DIY kit)*** IN STOCK!

Electrical tape works, but it will unwrap itself after a while. Heat shrink is better, but the trick is to
remember to put it on before soldering and to keep it far enough away from the soldering area.

The first time I used it I forgot to put it on before soldering, so I had to desolder what I just soldered,
sleeve it on, and then resolder. Then the heat from soldering caused it to shrink around the wire in the
wrong place so I had to cut a fresh piece and start all over again.

It is also possible to use the wrong size heat shrink. Too small and it won't fit over what you just
soldered. Too large and it doesn't make a tight seal when it shrinks.
 





yea Lazeerer told me a few days to do it so I tried that tape and I also covered the whole contact board with hot glue so the driver wouldn't touch the contact board and possibly touch in the wrong area.

I got two of them working. still working on the 3rd one and the 4th one I broke with a drill bit lol Noob mistake!

The Lightning Stalker said:
Electrical tape works, but it will unwrap itself after a while. Heat shrink is better, but the trick is to
remember to put it on before soldering and to keep it far enough away from the soldering area.

The first time I used it I forgot to put it on before soldering, so I had to desolder what I just soldered,
sleeve it on, and then resolder. Then the heat from soldering caused it to shrink around the wire in the
wrong place so I had to cut a fresh piece and start all over again.

It is also possible to use the wrong size heat shrink. Too small and it won't fit over what you just
soldered. Too large and it doesn't make a tight seal when it shrinks.
Click to expand...
 
Is there a guide which explains how many diodes to use in series depending on which Ld's we are trying to set the current for? That would make things simple and well explained for some people including me. Thanks.
James
 
Or perhaps a link to the relevant page as i didn't find it yet. Thanks, trying to understand how to setup my driver here before i blow my $100 diode setup b4 New years.
 
Each diode has a voltage drop of about 1.2V. the first diode is always in the circuit. so for each jumper location, multiply by 1.2 for the total voltage the load will drop across the driver. so you need to know the voltage drop across the laser diode you intend to use. you can find that in the data sheet. so for example a PL450B (a data sheet I happened to have open) says the operating voltage is between 5.8 and 7V. so I would set the load on 5 to give me 5 * 1.2 = 6V of drop. then you connect your meter across the test pins and 1mV=1mA... so if you want to set 300mA on the driver, you set your meter on VDC and set 300mV. The load simulates the voltage drop across the laser diode you want to use so you can adjust the current of the driver without having the actual LD connected there-by reducing risk of LD damage.

Get it?

Make sure to have your driver on a heat sink depending on whether it can run at full current without being sunk. you can sometimes get by without it being on a heat sink but the risks are all yours. :)
 
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@izzzzzz6: Here's a link how to use the test load. You'll have to know the voltage drop of the LD your using which can be found easily by searching the forums. The page in the link will help determine how many diodes to use depending on the current you want. Please also account for voltage drop of the resistor (V=IR). Also the voltage drop of each diode is 0.7V - 0.9V. :beer:

https://sites.google.com/site/thejuf88/home/electronics/usetestload
 
I need to test 10.5V operating 11.5A laser diode.
Would it be OK just to mount heatsing with thermal paste on this dummy load?

Can you make resistor and diodes suitable to handle 11.5A and allow load selecting to 10.5V?
 
zhivko said:
I need to test 10.5V operating 11.5A laser diode.
Would it be OK just to mount heatsing with thermal paste on this dummy load?

Can you make resistor and diodes suitable to handle 11.5A and allow load selecting to 10.5V?
Click to expand...

There has been quite a bit of discussion on this subject already which you would have found
had you used the search bar at the bottom of the page.

http://laserpointerforums.com/f67/testing-high-output-driver-pcb-86685.html

Cheap 35A Bridge Rectifiers
 
The question was for the creator of this nice dummy load, is it possible to adapt it so it could test higher currents like 11.5A and 10.5 Volts.

For "800 Volt 35 Amp MB35 Bridge Rectifier Diode" - should I connect resistor in series with it to mimic laser diode operation? If yes - what reistance and what wattage?

I atached pdf for laser diode in attachment - check electrical characteristics...
 

Attachments

Last edited:
Oh wow, 11.5A is a little too much for the diodes and resistor on the test load even with heat sinking. Sorry, but there isn't a way to test your laser diode on my test load. :(

That's a pretty beefy laser diode, what's your application for it?
 
Jufran88 said:
Oh wow, 11.5A is a little too much for the diodes and resistor on the test load even with heat sinking. Sorry, but there isn't a way to test your laser diode on my test load. :(

That's a pretty beefy laser diode, what's your application for it?
Click to expand...
Wanna cut some materials with it...
Can you please suggest parts so I can build my own dummy load?
resistor value, wattage of trasistor, and the quantity and part number of diodes and their current rates? They should be in series right?
 
Last edited:
Don' t use a resistor. Use instead a current sense shunt. BR5FB10L0 is a good part number for your
application. At 11.5A, your meter will read 115mV. It is rated 5W, so you will be able to safely
measure current up to about 22.5A continuous using that. Intermittently even more

Use the diode bridge rectifiers in my previous post. There is a even schematic posted if you follow that
first link. Get 12 of them just in case they are a little on the low side. The last one can either be
connected in the center as in the 3V example, or the same as the rest. You will know when the current
level starts getting close to your 11.5A target. Just measure the voltage drop across the diodes to get it
as close as you can.
 
Thank you very much. I am not from USA. It would be great if you can give me equivalent part number from Farnell.
I tried also to find shunt with no success...

Sent from my Nexus 5 using Tapatalk
 
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