For testing the pack discharger, we need to get some data on what a typical cell dropout looks like, so we can tune the dropout detection system.
This test version of the charger software allows us to hear a beep when the detection system wants to stop the discharge and start the recharge, but allows us to let it proceed past that point to be sure the detection caught a real drop out.
Here we see the cell drop out in three views, 1 as a part of the larger graph, 2, zoomed in with only the cell drop out filling the screen, and 3, using excel to graph the recorded data.
We see just about 1 V of drop at a much faster rate than the trend. One bit / 5 second samp-le, or about 20-30 seconds for the full drop. The discharge slope after the drop out went back to the same slope as before the drop out.
The detection system picked upthe drop out a bit after the second sample. Worked nicely.
You can see from this graph, that this 20-30 second event could have easily been missed just by looking at the display, as there is no trend line.
The Labview screen shot is part of the revised program taking into account some of the lessons learned last Sundays Labview class