Seasonic Power Angel : Can It Be 'Hacked'

[ToasterIQ2000]

I recently bought a Seasonic Power Angel, a nifty little device to measure power consumption.

I openened it up and I see that there are two circuit boards in it: one houses the AC in / out plugs; the other seems to be dedicated to the LCD display and buttons.

There are six wires connecting the two boards. From my familiarity with electronics I could resolder the wires to separate the butttons and LCD from the larger board and mount that half in a sigle drive bay faceplate -- mostly an informative and amusing bling-bling mod for a pc.

I'm curious though: what exactly is happening on those six wires? Do the buttons on the LCD panel signal the power monitoring board at all, telling it what to report? What sort of signal(s?) does the main board send to the display panel? 0-5 volt or 4-20ma process signals? RS485 protocol? Something uniqe designed into the power angel?

Those questions are over my head: all I can do is speculate. But I am curious if anyone on the SPCR forums would look at this and know... It occurs to me that somene far more familiar with the tech might investigate and come up with a way to make the meter report Amps, Volts, Power Factor, or Watts over a serial or USB port in the same manner that better uninterruptable power supplies can report things. Or extract info off those six wires and turn some part it into something that can be read via a fan tachometer header...

It is beyond my keen. Just tickles my imagination. I think it would be neat...

[qviri]

I'm in for USB hacking. A live, on-screen report as to how much power I'm eating by Folding just has that cool factor.

My electronics skills are slim, though, and I don't own a Power Angel. However, I certainly know the feeling of "ooh, new device! let's open it up, who gives a crap about warranty!"

[Felger Carbon]

The Power Angel and the Kill A Watt are the same device in different wrappers. The 16 pin IC on the analog board is a quad op amp. The 6 leads are power, ground (and here's some informed guessing) and the 4 outputs of the op amps. The 4 op amps provide the "half wave rectified" signals for current and voltage, normal and inverted. By inverted, I mean a negative voltage or current signal shows up as a positive output from the op amp. The microprocessor (that's what it is) on the display board quickly multiplies the two normal signals and the two inverted signals to get the instantaneous power. At any instant of time, at least one of the multiplications involves a zero input and so the multiplication of that pair can be skipped. It digitally averages many such multiplications to obtain a "steady" power reading.

This is possible because the "data rate" of the analog signal is 50 or 60 Hz, for a period of at least 8,300 microseconds of the rectified signal. Therefore, an inexpensive microprocessor/microcontroller is fast enough for this task.

I used to design stuff like this for a living.