R

#### Roque

- Jan 1, 1970

- 0

rated at 300W, what is the proper way to figure out what my actual power

usage is when I have this system running under its maximum load?

Here's what I've done so far....

I have a power supply that provides 24.5 volts and 5.1 volts DC output,

I find I can run a total current of 9 amps continuous, or 20 amps peak

before tripping the internal protection.

When I put a current probe on the 24.5 and 5.1 volt lines,

using a digital scope with math functions, I get 8 amps RMS on the 24 volt

line and 1.15 amps RMS on the 5.1 volt line, in my worst case use of the

machine.

I'm trying to decide what power dissipation I have...

With my scope, I saved 30,000 points of voltage and current data against

the same time line, and I

imported this V, I data to a spreadsheet....and created a new calculation

where I multiplied V * I for each data point...for instantanious power per

sample. I then squared each V * I data value, summed it, divided by 30,000

samples, and took the square root...hoping to find RMS power.

With 8 amps at 24.5 volts and 1.15 amps at 5.1 volts, I found about 200W

power dissipation...

Does this make sense? I'm not experienced with "power" electronics to be

confident about it so I wanted to seek advice.

Thanks.