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FrozenGate by Avery

My new baby 6A Dummy Load

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wee40811

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Apr 5, 2010
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I recently built my new dummy load. I use 1N5408 diode, ten of them. Can hold up to 6A 1000V.
some photo's
2011-06-07_05-13-13_239.jpg

2011-06-07_05-13-36_365.jpg
 





I'll see what will happened later on. I use a massive 5W resister. we'll se if it can hold.
 
Nice Work.:gj: I alway like looking at other testload/dummy loads that members create.:)

What ohms resistor do you use that is in between the 2 connectors in the very front.?

That 5W resistor is big but i would not call it massive.:D It will take ~3A for about 15-20 second but after that it will be to hot and you will see the heat coming off the thing.:eek:

A 10 watt one would help out alot but not sure if it will even mater at 6A. Or add a heatsink on top of the diodes an resistor.

+ :beer:
 
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The small one is for discharging the drive. It's 2.7K ohms. I have some 30Watts resister on hand:D I will see if it fits or some how fit it on the board.:drool:
 
Radioshack sell ones that are basically the same size as 2 of the board you used. There like $2 Bucks.
 
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Nice work. The ability to use a jumper is pretty neat.

A word of caution, though. Those diodes still get HOT under load. I used similar diodes for my test load (1N5404 rated for 3A), and I didn't give much thought into heat because they had such a high rating.

I wired them point-to-point with a 10W resistor, and when I used my test load to set my driver at 1.5A, the diodes got so hot after a couple minutes they melted the solder. So yeah don't use it for too long and let it cool off between uses. Doesn't matter what the rating of the diode is, it's still gonna get HOT. :whistle:
 
Why 6A? Show me a diode powered by a buck/boost that needs 6A. Hell, show me a buck/boost capable of reliably running a diode at 6A.

Each one of the diodes will generate ~6 watts of heat at full load. If they're in close proximity like that, they'll probably melt the solder.

6A across that 5W resistor means 36W of heat. Good luck with that.
 
Cyparagon said:
Why 6A? Show me a diode powered by a buck/boost that needs 6A. Hell, show me a buck/boost capable of reliably running a diode at 6A.
Click to expand...

There are some 750mW green portables that probably run off IRs in the range of 5 or so Watts - and presumably take nearly that amount in Amperage to drive. They probably use buck drivers.
 
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If you want wattage just buy a 200watt cheapie 1 ohm resistor. No heat sinking required and a god insane amount of current can be pumped through it. Only danger is you have to be careful about high wattage resistors. They are wire wound and thus you can get something called inductive kickback that can hurt all sorts of things.
 
What type of resistor is that? It looks like a sandstone wirewound type to me. If it is a wirewound, It is most likely inductive.
According to Dr Lava, if you use an inductive, wirewound resistor on your test load, you can burn out the inductor if used to set a boost driver. I'd suggest swapping that out for a metal oxide or a thick film type resistor. ;)

Edit ^^^^^ some random person must have posted seconds before me :D
 
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Cyparagon said:
Or a shunt with 5+ times the current capacity and 99% less heat, perhaps.
Click to expand...

Very good point...should have thought of that.. a shunt would work provided whatever wires you hook to the shunt have less resistance then the shunt itself. Otherwise you would drop the power across the wires which isn't always a good thing. 20A shunt can cost >8 bucks... and i'm sure they make them for much hire wattage. I just happen to have a few 20Amps on hand.
 
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