I performed some idling consumption tests before by Scan my Tesla but the CAN bus always shut off after about 1 or 2 hours making it impossible for long duration test.
Several days ago, I started the test again but this time I measure the voltage of the 12V battery directly and here are some results:
I set Energy saving off, Always connect on, the car was parked in 5C temperature (underground parking lot) for 4 hours before the test.
When I locked the door and left, the DC-DC was immediately off, the 12V battery last for less than 5 hours before the DC-DC kicked in, and remained charging/supplying for the rest of the test. The DC-DC current is measured by monitoring the voltage drop of the DC-DC fuse (F1, 250A) which is calibrated against the value from the CAN bus.
At the end, the battery dropped by 1.77kWh in 16 hours, or 2.8% per day, equivalent to 110W of power.
Another test result. This time, I set Energy saving on and always connected off.
Other conditions are the same as the last, which are:
Temperature 5 degree C
Firmware 2017.50.3
Test car X 100D build July 2017, mileage 4700km/2940mi
Test equip: Graphtec GL220 data logger
Sampling interval: 2s
CH1 range 20V
CH2 range 20mV
Test results:
DC-DC not started for the whole duration of the test.
Rated range dropped only 1.61km (562km when charged full), which is 1.61/562*94.1 = 0.27kWh, a drop of only 0.27% per day.
(It was 532.69km when the test start and 531.08 at the end, both recorded by Scan my Tesla)
However, there are voltage spikes of about 0.13V, and it happens every hour.
Here is one of the detailed spike. It seems to me that the 12 battery is being charged for about 15 seconds every time, but I measured *no* DC-DC current which normally is the source of charging. Any ideas why?
Several days ago, I started the test again but this time I measure the voltage of the 12V battery directly and here are some results:
I set Energy saving off, Always connect on, the car was parked in 5C temperature (underground parking lot) for 4 hours before the test.
When I locked the door and left, the DC-DC was immediately off, the 12V battery last for less than 5 hours before the DC-DC kicked in, and remained charging/supplying for the rest of the test. The DC-DC current is measured by monitoring the voltage drop of the DC-DC fuse (F1, 250A) which is calibrated against the value from the CAN bus.
At the end, the battery dropped by 1.77kWh in 16 hours, or 2.8% per day, equivalent to 110W of power.
Another test result. This time, I set Energy saving on and always connected off.
Other conditions are the same as the last, which are:
Temperature 5 degree C
Firmware 2017.50.3
Test car X 100D build July 2017, mileage 4700km/2940mi
Test equip: Graphtec GL220 data logger
Sampling interval: 2s
CH1 range 20V
CH2 range 20mV
Test results:
DC-DC not started for the whole duration of the test.
Rated range dropped only 1.61km (562km when charged full), which is 1.61/562*94.1 = 0.27kWh, a drop of only 0.27% per day.
(It was 532.69km when the test start and 531.08 at the end, both recorded by Scan my Tesla)
However, there are voltage spikes of about 0.13V, and it happens every hour.
Here is one of the detailed spike. It seems to me that the 12 battery is being charged for about 15 seconds every time, but I measured *no* DC-DC current which normally is the source of charging. Any ideas why?
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