Trying to build a test load

[Braddubya]

My plan for the test load was enough diodes in series to make the correct voltage drop and then a single 1ohm resistor of measuring the setting. I went to radioshack and started digging. Not being very experienced with DIY electronics I soon realized I was in over my head. There are alot of different diodes to choose from and I had no idea where to start. I was just looking for one with the lowest voltage drop I could find so I could tweak it for any laser diode but they all seemed much higher than the diodes most people have talked about using. There was also either alot of other technical data listed or no voltage drop listed at all. I was overwhelmed so I left without buying anything.

Can anyone help me out with what I need to look for and what can be ignored? Im planning to use this test load for up to 2A so if I can get pieces that wont overheat right away that would be nice.

I did find some 10A 1ohm resistors which seems ideal for this kind of current.

Thanks in advance :bowdown:

 

[udanis]

2 amp is a lot to ask out of these though.

 

[Flaminpyro]

1N4001 are fine if you are going to 1 amp or less other wise you will need to buy 1N5401 to get more current with out burning them up.
a 10 amp resistor will work just fine.

 

[Braddubya]

2 amp is a lot to ask out of these though.

Should these diodes be carried by radioshack? If so then thats perfect!

Also do the diodes get hot super fast of is it the resistor? or both? Because I found that 10A resistor.


Edit: Thanks flamingpyro that answers that question. Will those diodes handle the current and are they readily available at most radioshacks?

Sorry for all the specific questions im just trying to have everything in order before I drive back in to town.

 

[udanis]

Should these diodes be carried by radioshack? If so then thats perfect!

Also do the diodes get hot super fast of is it the resistor? or both? Because I found that 10A resistor.

Like stated above these are good for 1 amp and yes the do get hot. and yes are available at my local rat shack

 

[Braddubya]

Thanks all. Im off to radioshack again hopefully ill be back with the goods!

EDIT: Just called them and they dont have either of the diodes listed above. I also called all around town to electrical suppliers but it looks like the only place to buy individual pieces is radioshack.

They do have 1N5400 and 1N5402 but I have no idea if these will work...any help here?

EDIT 2: Upon more searching it looks like these diodes behave very similarly in certain aspects. Im still trying to see if they drop the voltage the same amount. If someone can verify this for me I will go grab them.

 

[Braddubya]

I got 6 3W 1N5400 and assembled them in series with a 10W 1ohm resistor. With this configuration however im only getting up to a little over 1000mv. its a flex drive with jumpers to the 1500mA range. Is my test load inaccurate or is there something wrong with the driver?!

 

[drlava]

you're over-volting the output of the flexdrive. at 1A those 6 diodes are 0.77V each and your 1 ohm load is 1V so that's 5.62V. Take 2 diodes out to get to 4V.

 

[Braddubya]

ahhh ok. I hope I can still adjust the pot without damaging it as I know these have limited use lifetime.

Thanks all for the help. Im seasoned in DIY complete noob to small electronics...