- 1 Introduction to the logging feature
- 2 Insert MicroSD Card
- 3 Connect from the app
- 4 Set the measurement parameters and logging interval
- 5 Leave the Mooshimeter until your experiment is complete
- 6 Retrieving the data
Introduction to the logging feature
The logging feature allows the Mooshimeter to record samples to a microSD card without user intervention for extended periods of time. Logging will occur whether or not the Bluetooth connection is maintained.
Insert MicroSD Card
The Mooshimeter records data to a microSD card. Before you can log data, you must insert an appropriate microSD card.
The microSD card slot is located on the side of the Mooshimeter next to the reset button. There is a slot in the polycarbonate case immediately above both of these features, but the slots are blocked internally for safety reasons. To access the slots, you must open the case by loosening the two screws in the back of the device and pulling the bottom cover off. You do not need to remove the PCB from the top cover to access the SD card.
The connector is a push-push type. When inserting, push the microSD card in to the connector until you hear a click. To remove it, push again until you hear a click and when you remove your finger the card will be ejected.
A full demonstration of Mooshimeter disassembly is below:
Connect from the app
Connect to the Mooshimeter you want to start logging from the Scan Page of the Mooshimeter App.
Set the measurement parameters and logging interval
While logging unattended, the Mooshimeter will hold whatever measurement parameters were last set through the app. More information is available on the Using the Apps page.
Note on measurement ranges: The meter will not autorange while logging unattended. Be sure to set the range to capture the largest value you expect to see while logging*. Example: If you are logging a voltage that might fluctuate between 40V and 200V, you should set the voltage measurement range of the meter to the 600V range instead of the 60V range. If you leave the meter in the 60V range while logging and the value being logged goes beyond the measurement range, out of range values will be logged.
When measurement has been properly configured, set the logging interval on the Meter Settings page. The logging interval determined how often a sample will be recorded to the SD card. Shorter logging intervals increase battery usage but give you more detailed information. A logging interval of 0 will cause the meter to continuously sample and record data to the SD card.
You should choose the longest logging interval that will allow you to capture the phenomenon you're looking for. A longer logging interval saves battery and produces smaller files. If you leave a Mooshimeter logging at a 1s interval for a week, you will end up with a CSV of 604,000 lines, which causes many spreadsheet programs to perform slowly.
On the Meter View Page, the bottom left button reflects the state of logging on the meter. If the SD card is inserted and properly formatted, it will say "LOGGING:OFF" or "LOGGING:ON", and tapping the button will toggle between the two states. If there is no SD card or there was an error communicating with it, the button text will give a brief description of the error.
Leave the Mooshimeter until your experiment is complete
You can disconnect from the Mooshimeter and it will continue to record samples until you remove the SD card or reconnect and turn off logging manually.
The LED will give a triple-blink every time a sample is recorded to the SD card. More information on LED blink patterns can be found here.
Retrieving the data
For firmware versions < 14770000000, the SD card must be retrieved. For later firmware versions, the data can be streamed out over BLE.
Retrieving the SD card
Turn off logging
Before removing the SD card, we recommend turning off logging through the app. If you skip this step, there is a small chance that you will remove the SD card while the Mooshimeter is writing to it, causing data corruption.
Accessing the SD card
The logs are stored on the MicroSD card in a CSV (comma separated value) format, which can be imported in to any spreadsheet program. To access the SD card, see the instructions above for inserting the card.
Streaming out the logs over BLE
For firmware versions > 14770000000, the data can be streamed out over BLE. The procedure is as follows:
- Connect to the Mooshimeter
- Press the Logging Button from the Metering page
- You will be brought to the Logging Preferences page. If an SD card is installed and mounted, you can press the "Load available logs" button. The app will load a list of logs available on the SD card, including their last entry and size
- Tap the log you'd like to download and the download process will begin
- On Android, the log will be saved to your external flash (on some Android phones this is an external SD card, on some it's just a section of flash memory) in a folder called MooshimeterLogs
- On iOS, the storage available to apps is segmented and the log will be stored in the Mooshimeter App's designated storage space
- Once the download process has completed, the app will attach the log to an email and raise a "compose email" prompt for easy sharing