lazeerer
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Thanks Guys. Happy you like it.:wave:
Did you miss the start of the thread with the text.?
:beer:
It can take ~3A with no heatsink.
It can take ~5-6A with a small heatsink put on top of the 1 ohm resistor.
I have not made the heatsink yet that will mount on the bottom but iam sure it will have no probably doing 10A.
When i have time messing with that i will. For now this has no problems for what iam doing with a small heatsink.
The Accuracy of a .1ohm resistor will get very expensive and i dont think they come in this package device.
If my Jib 3A testload can do 7A heatsinked then this will have no problem.
Some times its better to keep things simple.
Have you actually tested it at 20A, or even 10A for that matter? I highly doubt it will survive that without desoldering itself or popping that tiny jumper.
Did you miss the start of the thread with the text.?
:beer:
Now before i go into the pictures i want to say that I got a little excited with the "AMP" rating and called it a 20A Testload. I can say now there is No way this Testload is going to take 20A.!LOL It can take ~ 3A without a heatsink on the 1 ohm Resistor. That is the main Issue and only issue with heat really the diodes can take it pretty good but the 1 ohm resistor cant. The 1 ohm resistor gets so hot it will desolider itself.LOL It happened to my Jib Testload So i new it will happen here.
So what i did was i left exposed copper on the bottom where it was needed and i plain on mounting the Testload entire bottom on a heatsink "Then" it will be installed in the case. Even then i would probably only be able to dump around 10A into it for a few minutes.
However i designed it so that i can also use this Testload without the case and with the 4 screw mounts i can mount it to heatsink i have in mind. "More on that bellow" That should allow me to run it continuous at ~10A or possible more with no issue.
It can take ~3A with no heatsink.
It can take ~5-6A with a small heatsink put on top of the 1 ohm resistor.
I have not made the heatsink yet that will mount on the bottom but iam sure it will have no probably doing 10A.
You could switch to a 0.1ohm resistor instead of 1ohm pretty easy. All you have to do is change the voltage divider so it reads up to 1.9999v but leave the decimal point selector in the same spot so the amps display correctly.
10w in the resistor at 10A is much more reasonable than 100w. Also the 1ohm resistor alone would be dropping 10v, I doubt any 10A driver you are making will handle a load that high
When i have time messing with that i will. For now this has no problems for what iam doing with a small heatsink.
The Accuracy of a .1ohm resistor will get very expensive and i dont think they come in this package device.
If my Jib 3A testload can do 7A heatsinked then this will have no problem.
Some times its better to keep things simple.
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