HOBO MX Soil Moisture (MX2306) and MX Soil Moisture and Temperature (MX2307) Data Logger Manual
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7. Tap Stop Logging and specify when logging ends:
•Never Stop (Overwrites Old Data). The logger does
not stop at any predetermined time. The logger
continues recording data indefinitely, with newest data
overwriting the oldest.
•On Date/Time. The logger stops logging on a specific
date and time that you specify.
•After. Select this if you want to control how long the
logger should continue logging once it starts. Choose
the amount of time you want the logger to log data.
For example, select 30 days if you want the logger to
log data for 30 days after logging begins.
•Stop When Memory Fills. The logger continues
recording data until the memory is full.
8. Tap Pause Options, then select Pause On Button Push to
specify that you can pause the logger by pressing its
Start/Stop button for 3 seconds.
9. Tap Logging Mode. Select either Fixed Logging Mode or
Burst Logging. With fixed logging, the logger records data
for all enabled sensors and/or selected statistics at the
logging interval selected (see Statistics Logging for details
on choosing statistics options). In burst mode, logging
occurs at a different interval when a specified condition is
met. See Burst Logging for more information.
10. Enable or disable Show LED. If Show LED is disabled, the
alarm and status LEDs on the logger are not illuminated
while logging (the alarm LED does not blink if an alarm
trips). You can temporarily turn on LEDs when Show LED is
disabled by pressing the button on the logger for 1 second.
11. Enable or disable Bluetooth Always On. If Bluetooth Always
On is enabled, the logger advertises or regularly sends out a
Bluetooth signal for the phone, tablet, or computer to find
via the app while it is logging, which uses battery power.
When Bluetooth Always On is disabled, the logger only
advertises during logging when the button on the logger is
pressed to wake it up, thereby preserving as much battery
power as possible.
12. Select Soil Type:
•Mineral – for common soils, with EC values up to 8
dS/m.
•Soilless – for potting soils, perlite, and peat moss with
EC values up to 8 dS/m.
•Apparent Dielectric Permittivity – raw measurements
that can be used in published equations such as the
Topp equation to derive soil moisture data.
13. Enable or disable Percent of Field Capacity – To see soil
moisture as the percent of field capacity, enable this and
enter the field capacity for the soil at the site in Volumetric
Water Content on a scale of 0.01 to 1.00. Note that the
Percent of Field Capacity values reported are limited to the
range of 0% to 200%. If you selecte Apparent Dielectric
Permittivity as your soil type, the option for Percent of Field
Capacity is disabled.
14. Select whether to upload data to HOBOlink using the
HOBOconnect app or the MX Gateway. Uploading data to
HOBOlink requires that you create a HOBOlink account. If
you offload data using HOBOconnect you don't need to
upload your data to HOBOlink. If you are using the Gateway
you must have a HOBOlink account.
15. Enable/Disable the sensors to log (MX2307 model) and set
up any alarms to trip when a sensor reading rises above or
falls below a specified value. See Setting up Alarms for
details on enabling sensor alarms. Note that for the
MX2307, temperature is Channel 3. Channel 2 is reserved
for Apparent Dielectric Permittivity, if you select it.
16. Tap Start to save the configuration settings, and start
logging based on the settings you selected. Press the start
button on the logger if it was set up to start logging with a
button push. See Deploying and Mounting the Logger for
details on mounting and see Reading Out the Logger for
details on downloading.
Setting up Alarms
You can set an alarm to trip on the logger when a sensor
reading rises above or falls below a specified value. Alarms alert
you to problems so you can take corrective action. To set an
alarm:
1. Tap Devices.
2. Tap the logger tile in the app to connect to the logger and
tap Configure & Start.
3. Tap a Sensor/Channel and tap Enable Logging, if necessary.
4. Tap Alarms to open that area of the screen.
5. Select Low if you want an alarm to trip when the sensor
reading falls below the low alarm value. Enter a value to set
the low alarm value.
6. Select High if you want an alarm to trip when the sensor
reading rises above the high alarm value. Enter a value to
set the high alarm value.
7. For the Duration, select how much time should elapse
before the alarm trips and select one of the following:
•Cumulative Samples. The alarm trips once the sensor
reading is out of the acceptable range for the selected
duration any time during logging. For example, if the high
alarm is set to 85°F and the duration is set to 30 minutes,
the alarm trips once the sensor readings have been
above 85°F for a total of 30 minutes since the logger was
configured.
•Consecutive Samples. The alarm trips once the sensor
reading is out of the acceptable range continuously for
the selected duration. For example, the high alarm is set
to 85°F and the duration is set to 30 minutes, the alarm
trips only if all sensor readings are 85°F or above for a
continuous 30-minute period.
8. For the MX2307, repeat steps 2–7 for the other sensor.
9. In the Alarm Settings area, select one of the following
options to determine how the alarm indications are cleared:
•Logger Reconfigured. The alarm icon indication appears
until the next time the logger is reconfigured.
•Sensor in Limits. The alarm icon indication displays until
the sensor reading returns to the normal range between
any configured high and low alarm limits.
When an alarm trips, the logger alarm LED blinks every 4
seconds (unless Show LED is disabled), an alarm icon appears in
the app, and an Alarm Tripped event is logged. The alarm state
clears when the readings return to normal if you have specified
Sensor in Limits in step 9. Otherwise, the alarm state remains in
place until the logger is reconfigured.
