Lookin to build the 2/4/8 version 2 : https://www.aikenamps.com/images/Docume ... myLoad.pdf
What sized Hammond enclosure will I need for proper dissipation and would I need any sinks?
Enclosure for Aiken's Resistive Dummy load
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Smokebreak3
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Enclosure for Aiken's Resistive Dummy load
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Re: Enclosure for Aiken's Resistive Dummy load
A good place to start is the datasheet for the resistor you plan to use. The model in Aiken's schematic is pretty easy to find.
https://www.vishay.com/docs/30201/rhnh.pdf
Page 3 has a lot of relevant info:
There's a couple graphs that basically reiterate those same two points and also show how much to derate the resistor if the ambient temp is warmer than ideal or the heatsink size is smaller than ideal.
Your personal uses are going to determine what kind of design goals you should aim for. Are you planning on using this with any amps that are close enough to the 50 watts per resistor limit that you need to do all of the math, or are you planning on using this with much smaller amps and trying to make it as compact as possible?
https://www.vishay.com/docs/30201/rhnh.pdf
Page 3 has a lot of relevant info:
Or you can derate it to 20 watts if you're not using a heatsink.Vishay RH resistor wattage ratings are based on mounting to the following heat sink:
RH050: 12" x 12" x 0.059" thick aluminum panel (291 sq. in. surface area)
There's a couple graphs that basically reiterate those same two points and also show how much to derate the resistor if the ambient temp is warmer than ideal or the heatsink size is smaller than ideal.
Your personal uses are going to determine what kind of design goals you should aim for. Are you planning on using this with any amps that are close enough to the 50 watts per resistor limit that you need to do all of the math, or are you planning on using this with much smaller amps and trying to make it as compact as possible?
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Smokebreak3
- Posts: 59
- Joined: Wed Dec 28, 2022 12:45 am
Re: Enclosure for Aiken's Resistive Dummy load
Cool thanks for that. I wonder how those numbers change for five 50W resistors. Certainly it wouldn't be a 60"x60" box 
I've got a chassis kickin around here that's 16"x 7" and .09" thick. I imagine that will be plenty, based on the sizes of boxes I've seen used.
I've got a chassis kickin around here that's 16"x 7" and .09" thick. I imagine that will be plenty, based on the sizes of boxes I've seen used.