Puzzled by Battery Capacity Settings on 9XR Pro

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Puzzled by Battery Capacity Settings on 9XR Pro

Post by gweep » Mon Sep 16, 2019 4:15 am

I am trying to understand the CAPACITY LOW setting on my 9XR Pro (openTX 2.2.4). This setting shows up in RADIO SETUP menu, page 1/9, in the Alarms section.
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Radio Setup 1/9: Alarms: Capacity Low
I can only assume this is a setting for the TX battery. It has units of mAh. I have read somewhere for a completely different radio (and maybe not openTX) that this is the accumulated mAh drawn by the TX and is used to trigger an alarm. It was suggested to set it at 80% of the battery capacity. 80% of my 2200 mAh TX battery would be 1760 mAh.

Also from the RADIO SETUP menu, page 7/9, CURRENT CALIB as a current calibration parameter. My radio lets me adjust the current calibration to be in the range of 560 ma to 685 mA. I have measured the actual TX current draw to be 220 mA. Off by a factor of about 2.7! (The screen shots do not reflect the actual values displayed on my transmitter.)
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Radio Setup 1/7: Analogs: Current calibration
The third location is in the DEBUG screen which is arrived at with a long push on the UP button followed by a short button push on the UP button to move beyond the STATS screen. Here it displays a the current draw (CURRENT mA) on the 1st line and a current consumption value ( CONSUMPT. mAh) on the 2nd line. The accumulated consumption on the 2nd line can be reset to zero for a freshly charged battery by selecting and pressing the MENU button.
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DEBUG Screen: DEBUG: Contempt.
Watching the current CONSUMPT. display on the DEBUG screen; I estimate it is clocking out at 3840 mAh when it should be showing only 220 mAh. (Off by more than a factor of 17.)

Right now I have the CAPACITY LOW parameter set to 0 mAh. This appears to disable the alarm.

Someone help me out here. What is the correct way to setup this featue? What am I missing? Is this an openTX bug? Should I report it?


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