HOBO MX2300 Series Data Logger Manual
1-800-LOGGERS 5 www.onsetcomp.com
6. For the Duration, select how much time should elapse
before the alarm trips and select one of the following:
•Cumulative. The alarm will trip 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, then the
alarm will trip once the sensor readings have been above
85°F for a total of 30 minutes since the logger was
configured.
•Consecutive. The alarm will trip 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, then the
alarm will only trip if all sensor readings are 85°F or
above for a continuous 30-minute period.
7. Tap Save and repeat steps 3–7 for the other sensor if
desired.
8. In the configuration settings, select one of the following
options to determine how the alarm indications are cleared:
•Logger Reconfigured. The alarm indication will display
until the next time the logger is reconfigured.
•Sensor in Limits. The alarm icon indication will display
until the sensor reading returns to the normal range
between any configured high and low alarm limits.
9. Tap .
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
will clear when the readings return to normal if you selected
Sensor in Limits in step 8. Otherwise, the alarm state will
remain in place until the logger is reconfigured.
Notes:
•Alarm limits are checked at every logging interval. For
example, if the logging interval is set to 5 minutes, then
the logger will check the sensor readings against your
configured high and low alarm setting every 5 minutes.
•The actual values for the high and low alarm limits are set
to the closest value supported by the logger. In addition,
alarms can trip or clear when the sensor reading is within
the resolution specifications.
•When you read out the logger, alarm events can be
displayed on the plot or in the data file. See Logger
Events.
Burst Logging
Burst logging is a logging mode that allows you to set up more
frequent logging when a specified condition is met. For
example, a logger is recording data at a 5-minute logging
interval and burst logging is configured to log every 30 seconds
when the temperature rises above 85°F (the high limit) or falls
below 32°F (the low limit). This means the logger will record
data every 5 minutes as long as the temperature remains
between 85°F and 32°F. Once the temperature rises above
85°F, the logger will switch to the faster logging rate and record
data every 30 seconds until the temperature falls back to 85°F.
At that time, logging then resumes every 5 minutes at the
normal logging interval. Similarly, if the temperature falls below
32°F, then the logger would switch to burst logging mode again
and record data every 30 seconds. Once the temperature rises
back to 32°F, the logger will then return to normal mode,
logging every 5 minutes. Note: Sensor alarms, statistics, and the
Stop Logging option “Wrap When Full” are not available in
burst logging mode.
To set up burst logging:
1. Tap Devices. Press the button on the logger to wake it up (if
necessary).
2. Tap the logger in the app to connect to it and tap .
3. Tap Logging Mode and then tap Burst Logging.
4. Select Low and/or High and either type or drag the slider to
set the low and/or high values.
5. Repeat step 4 for the other sensor if desired.
6. Set the burst logging interval, which must be faster than the
logging interval. Keep in mind that the faster the burst
logging rate, the greater the impact on battery life and the
shorter the logging duration. Because measurements are
being taken at the burst logging interval throughout the
deployment, the battery usage is similar to what it would be
if you had selected this rate for the normal logging interval.
7. Tap Save.
8. Tap .
Notes:
•The high and low burst limits are checked at the burst
logging interval rate whether the logger is in normal or
burst condition. For example, if the logging interval is set
to 1 hour and the burst logging interval is set to 10
minutes, the logger will always check for burst limits
every 10 minutes.
•If high and/or low limits have been configured for more
than one sensor, then burst logging will begin when any
high or low condition goes out of range. Burst logging will
not end until all conditions on all sensors are back within
normal range.
•The actual values for the burst logging limits are set to
the closest value supported by the logger.
•Burst logging can begin or end when the sensor reading is
within the resolution specifications. This means the value
that triggers burst logging may differ slightly than the
value entered.
•Once the high or low condition clears, the logging
interval time will be calculated using the last recorded
data point in burst logging mode, not the last data point
recorded at the normal logging rate. For example, the
logger has a 10-minute logging interval and logged a data
point at 9:05. Then, the high limit was surpassed and
burst logging began at 9:06. Burst logging then continued
until 9:12 when the sensor reading fell back below the
high limit. Now back in normal mode, the next logging
interval will be 10 minutes from the last burst logging
point, or 9:22 in this case. If burst logging had not
occurred, the next data point would have been at 9:15.
•A New Interval event is created each time the logger
enters or exits burst logging mode. See Logger Events for
details on plotting and viewing the event. In addition, if
the logger is stopped with a button push while in burst
logging mode, then a New Interval event is automatically
