Stardate: 20190205.1822
Location: Work Cubicle
Input Device: Gemini PDA
Audio: Pete Tong - Essential Selection Spring 2000
Visual: Work desk with monitors, Das Keyboard 4 Ultimate, USB 
fireplace, homemade USB xmas lantern w/lights.
Energy: 70%
Mental: 70%
Emotional: Amplified from coffee and techno music.


I brought out my West Mountain Radio CBA II (Computerized 
Battery Analyzer)[1] the other weekend and tested the 
capacity of the batteries for the Cybah Rig.  The batteries I have 
been using are the APC M12USWH, which are the batteries used 
for the APC Back-UPS Connect 50 Lithium Ion Network UPS / 
Mobile Power Bank.[2]  I have this running as backup for a 
Raspberry Pi server at home and since I had a spare battery, 
or so I thought, I decided to use the spare for the Cybah 
Rig and swap out the batteries for charging.

Previously, one of the batteries had failed while I was 
writing a phlog entry and I lost most of the contents of the 
file I was writing. [3]  This prompted for the battery 
capacity testing.

My setup was basically my Fujitsu P1610 running Windows XP 
Tablet and Offline Edition running CBA II software, CBA II 
unit, a bunch of test cables, and the APC USB battery.  The 
battery's capacity is 11400mAh.  During my test I set the 
load at 1 Amp @ 5 volts.  Typically, the Cybah Rig runs less 
than 800 milliAmps at 5 volts.  This is including the 
Raspberry Pi Zero W and the Fujitsu FMD-250w.  Here's a pic 
of the setup.[4]

The first battery, which I labeled as APC1 turned out to be 
good.  I tested this one with 5 volts at 1 Amp load.  This 
resulted in 33.09Ah total, which I found strange since the 
battery is only rated at 11400mAh.  I might need to retest 
this one, but the capacity is good.  Here is the graph of the 
results. [5]

The second battery was labeled APC2 and this one turned out 
to be the bad one.  It resulted in only 1.24Ah total.  I will 
retest this one as well, but I think it's spent.  Hopefully, 
I can take it apart and replace the internal battery cheaper 
than buying a new one.  Here are the results. [6]

I had tested the load of the Cybah Rig with a neat little 
Chinese USB muli-tester (UM25C) that I picked up on Amazon. 
[7]  It's pretty neat because it can test voltage, current, 
resistance, etc., accepts different cable types, has a pretty 
display.  It also has bluetooth that you can view the data 
on your laptop or Android device in real time as well as save 
the data from your tests.  Not sure how much I trust the app 
so I have it running on test devices.  The USB tester is so 
much better than the makeshift ghetto rigs I set up with my 
multimeter.  Plus it logs the data.

Here is a picture of the UM25C attached to the APC USB 
battery on one end and the Cybah Rig on the other.  The meter 
shows the current load of 0.5429Amps at 4.986 volts. [8]

Here is a picture of the graphed results of the Cybah 
Rig with the Face-Mounted Display in use and the Raspberry 
Pi Zero W running system updates.  I only ran it for about 
10 minutes and then shut down after the updates were done.  
The data was exported from the Android application 
and imported into Excel for the pivot graph.  The total load 
did not go over 0.9Amps (or 900 milliAmps.) [9]

If the capacity of the APC1 battery is truly 33.09Ah, I can 
get over 36 hours of runtime for the Cybah Rig!  Not that I 
need that much...my eyes would probably start bleeding and 
I'd be vomiting well before I hit that threshold.

[1] West Mountain Radio

[2] APC Back-UPS Connect 50

[3] 20190120_cybah_rig

[4] APC M12USWH Battery Capacity Testing Setup
- APC M12USWH 11400mAh, 41.2Wh(rating), 5v@2.4A USB, 5v@1A USB
- Fujitsu P1610 -> USB type A male to USB type B male -> 
       West Mountain CBA II -> Home made power pole to T connector 
       pigtail -> T Connector to alligator clip pigtail -> 
       male jumper wire to male jumper wire -> female 
       breadboard jumper wire to USB -> APC M12USWH Mobile 
       Power Pack.
[5] Good battery
     - Graph of CBA II capacity test results for APC 1 
       battery (5 volts @ 1A load, 33.09Ah total)
[6] Bad battery
     -  Graph of CBA II capacity test results for APC 2 
       battery (5 volts @ 1A load, 1.24Ah total.)
[7] UM25C USB Meter

[8] UM25C USB Load Test
    - UM25C USB meter hooked up to Cyber Rig showing load @ 
      0.5429A @ 4.986v  
[9] UM25C results
- Graphed results of Cybah Rig from the UM25C USB meter.


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