erock1331
Go to the Competition Electronics Web site and under the GFX download the Extended Users Manual for the charger.
Then get a Serial cable and connect the GFX to a laptop or other PC with a serial port. Follow the instuctions in the Extended Users Manual.
Per the manual setup the GFX to give you readings to the port in 1 sec intervals. Take the data and follow the instructions for making a graph in Microsoft Excel.
My brother and I have been able been get almost to the exact second results between our two chargers with the same battery pack. My understanding from talking to CE this is more accurate than what you see on the display.
Also, the power supply you are connected to and how clean the power that is coming from the power supply will depend on how accurate your results are going to be. When I run my charger at the track I have always recieved different results than when I am home. At home I use a power supply that is designed to clean all the noise coming from the power line. I have a very old pyramid 40Amp regulated and noise filtered power supply at home that is used for Ham Radio equipment and I always get better results at home.