Pico diagnostics battery test

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jueja
OneWave
OneWave
Posts: 30
Joined: Sun Sep 19, 2021 4:20 am

Pico diagnostics battery test

Post by jueja »

markers_1.jpg
Within the graph of the generated report of the battery test several vertical black lines come up. What exactly do they represent and is there a pattern to these markers?

While the first one always seems to mark the point of max. current draw and voltage drop the last one may show the point in time where the starter motor stops putting an electrical load on the battery?

In some of the captures it looks like every second line after the initial one goes along with TDC of a cylinder, judging by the current humps. But this does not hold true with every test, especially on engines which take a couple of seconds to catch up.

Thank you for taking the time to read.

Steve Smith
Pico Staff Member
Pico Staff Member
Posts: 1356
Joined: Sun Aug 25, 2013 7:22 am

Re: Pico diagnostics battery test

Post by Steve Smith »

Hello and thank you for the post

The vertical markers denote a considerable change in voltage or current during the cranking phase with respect to the trend of either signal (Channel A Voltage, Channel B Current)

For example, if our voltage and current were perfectly uniform in respect of their rise and fall during cranking, we should see vertical markers placed at the min and max points of both voltage and current. These markers then serve as phase rulers to denote approx. 90° of crankshaft rotation at max voltage & min current intervals and 180° at min voltage and max current intervals (4 cylinder engine)

However, as you have highlighted, there are times when a considerable change in voltage or current will be detected by the software and a marker placed at a point of no true value other than to indicate a “change”.

Such a change could occur due to a voltage spike or indeed "noise" which may not be clearly visible in the graph view but sufficient for detection by the software

I will add a New Feature Request for the software team to review and triage surrounding the improved placement of these vertical markers to denote areas of relevant interest during cranking rather than spike or noise events

I hope this helps, take care…..Steve

jueja
OneWave
OneWave
Posts: 30
Joined: Sun Sep 19, 2021 4:20 am

Re: Pico diagnostics battery test

Post by jueja »

Thank you Steve for the explanation!

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