test/dummy load

[Chrisbee]

Anyone have any sources for a good test load?
I know of Jufran88's 3A test load, which looks nice. But he hasn't been active since February, so I'm not sure if those are still available. I thought that I'd ask here first before I waited for an unknown amount of time for him to respond. I think 3A would do fine for now, as I try to get preset drivers for my higher power builds anyways.
Any help appreciated! :thanks:

 

[ElectricPlasma]

This is quite interesting, I bought it on eBay about a week ago:

EBD-M03 Mini Electronic Load Test Board Battery Capacity Mobile Power Tester

It's got a max of 3A, and has an ammeter and a voltmeter
build into an LCD. Max of 20V as well.

 

[BowtieGuy]

Chrisbee, I believe Survival Lasers have two models of test load available, THIS one is similar to jufrans 3A test load, and the other is a more expensive 20A rated model.

 

[Pi R Squared]

Anyone have any sources for a good test load?
I know of Jufran88's 3A test load, which looks nice. But he hasn't been active since February, so I'm not sure if those are still available. I thought that I'd ask here first before I waited for an unknown amount of time for him to respond. I think 3A would do fine for now, as I try to get preset drivers for my higher power builds anyways.
Any help appreciated! :thanks:

Yes Survival Laser is still selling them, this is the one I have:
3A Selectable Test Load
They also are selling a new more heavy duty one:
20A Heavy Duty Selectable Test Load
You could also just buy parts and put together one yourself.

Alan

 

[VirtueViolater]

I have the 3amp survival laser ted t load,
Works great,
Danny

 

[Cyparagon]

EBD-M03 Mini Electronic Load Test Board Battery Capacity Mobile Power Tester

It's got a max of 3A, and has an ammeter and a voltmeter
build into an LCD. Max of 20V as well.

That's a constant current load, and will not work with a constant current source. Even if it were capable of constant voltage, transistor-based loads can be unstable... especially cheap chinese garbage like that.

 

[Benm]

Indeed. The reason we use these funny diode-resistor combination loads is because their current/voltage curve roughly measures that of real laser diodes.

The point of testing a driver is that it can deal with a strange load like that. Those electronic loads are the opposite: they provide ideal current sinks and draw the current set no matter what the output voltage does.

The diodes + resistor dummy load allows you to check what happens if you connect and actual laser diode. If you have a scope you can also detect potential problems like current spikes when turning on.

 

[Chrisbee]

Cool, thanks guys! Looks like Survival Lasers it is.
BTW, I have seen some random ones on eb@y. But being what we use them for, I just wasn't sure if those would work. At least this way I know what I'm getting. :yh:

 

[VirtueViolater]

The 3amp test load from survival is well made, I soldered clip leads onto the driver input on the pcb,
Danny

 

[Chrisbee]

Nice! Good idea!

 

[VirtueViolater]

Was thinking those cheap Chinese digital ameter/voltometer combo's in a project box with a couple press connecters and this test load would be sweet. Just hook driver to it and adjust

 

[Chrisbee]

That would be nice to have a fully dedicated setup. I know those digital volt meters at Harbor freight can be had for under $10. I don't know if it's a ammeter though. Also, if it was all setup in a custom project box, you could add your own heat sink for the test load. I have access to small aluminum scrap, so it'd be pretty easy get something like that put together.

 

[Benm]

You could simply build the 'default' dummy load from a number of silicon diodes and a resistor in series, and then add the meters to that setup.

Considering the power requirements of the meters you could power them straight from the input voltage if you are testing for higher power laser drivers, or an external supply for lower powers.

Most people are interested primarily in current, but it can be nice to be able to measure voltage at the same time. I would however suggest using LCD ones as they draw less current and interfere with your measurements less if you do power them from the input.

 

[VirtueViolater]

Thanks Benm,
May be a project I do soon
Danny