HOBO U24 Conductivity Logger Manual
2
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Plot A: Salinity Range (U24-002)*
Plot B: Specific Conductance Range in Saltwater
* The Practical Salinity Scale 1978 (PSS-78) used to calculate salinity
is valid for salinities in the range of 2 to 42 ppt. For salinities
outside of this range, use the measured conductivity and
temperature data from the logger with a calculation appropriate
for your salinities.
Plot C: Comparison of Conductivity Calibrated Measurement Ranges
Protecting the Logger
IMPORTANT:
This logger can be damaged by shock. Always handle the logger with care. The logger may be damaged if it is
dropped. Use proper packaging when transporting or shipping the logger.
Do not attempt to open the logger case or sensor housing. Disassembling of the logger case or sensor housing will cause
serious damage to the sensor and logger electronics. There are no user-serviceable parts inside the case. Contact Onset
Technical Support at 1-800-LOGGERS (1-800-564-4377) or an authorized Onset dealer if your logger requires servicing.
Operation
•
The logger requires HOBOware Pro version 3.2 or higher, and the Conductivity Assistant, version 1.8 or higher.
•
An LED in the communications window of the logger confirms logger operation. When the logger is logging, the LED
blinks once every one to four seconds (the shorter the logging interval, the faster the LED blinks). The LED also
blinks when the logger is recording a sample.
When the logger is awaiting a start because it was launched in “Start at Interval” or “Delayed Start” mode, the LED
blinks once every eight seconds until logging begins.
Logger Case
Sensor Housing
Sensor Face
Do not scratch the sensor
face with a sharp tool.
