HOBO MX2300 Series Data Logger Manual
1-508-759-9500 (U.S. and International) 5
www.onsetcomp.com
1-800-LOGGERS (U.S. only)
5.
Tap Alarms to open that area of the screen.
6.
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.
7.
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.
8.
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,
then 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, then the
alarm trips only if all sensor readings are 85°F or above
for a continuous 30-minute period.
9.
Repeat steps 2–8 for the other sensor.
10.
In the configuration settings, select one of the following
options to determine how to clear the alarm indicators:
•
Logger Reconfigured.
The alarm indicator is displayed
until the next time the logger is reconfigured.
•
Sensor in Limits.
The alarm icon indicator is displayed
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 selected
Sensor in Limits in step 10. Otherwise, the alarm state remains
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 checks 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 download data from 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 records 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 switches to the faster logging rate and records data
every 30 seconds until the temperature falls back to 85°F. At
that time, logging resumes every 5 minutes at the fixed logging
interval. Similarly, if the temperature falls below 32°F, the
logger switches to burst logging mode again and records data
every 30 seconds. Once the temperature rises back to 32°F, the
logger returns to fixed mode, logging every 5 minutes.
Note:
Sensor alarms, statistics, and the Stop Logging option Never
Stop (Overwrites Old Data) are not available in burst logging
mode.
To set up burst logging:
1.
Tap Devices. Press the Start/Stop button on the logger to
wake it up, if necessary.
2.
Tap the logger tile in the app to connect to the logger and
tap Configure & Start.
3.
Tap Logging Mode and then tap Burst Logging.
4.
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.
5.
Select Low and/or High and type a value to set the low
and/or high values.
6.
Repeat step 5 for the other sensor if desired.
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 always checks for burst limits every
10 minutes.
•
If high and/or low limits are configured for more than
one sensor, burst logging begins when any high or low
condition goes out of range. Burst logging does 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 from the
value entered.
•
Once the high or low condition clears, the logging
interval time is 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 is surpassed and burst
logging begins at 9:06. Burst logging then continues until
9:12 when the sensor reading falls back below the high
limit. Now back in fixed mode, the next logging interval is
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
