Hobo U12 User manual

HOBO® U12 Deep Ocean Temperature
Logger (U12-015-03) Manual
14767-C MAN-U12-015-03
The HOBO U12 Deep Ocean Temperature Logger is a single-channel
temperature logger with 12-bit resolution that can record up to 43,000
measurements. With its robust titanium housing, this logger is designed to
withstand the rigors of saltwater deployment. It has a depth rating to 11,000
meters and a temperature range from -40° to 125°C, making it the ideal logger
to handle the ocean extremes of depth and temperature.
Specifications
Measurement Range -40° to 125°C (-40° to 257°F)
Accuracy ±0.22°C at 25°C (±0.4°F at 77°F), see Plot A
Resolution 0.025°C at 25°C (0.045°F at 77°F), see Plot A
Drift 0.05°C/year + 0.1°C/1000 hrs above 100°C (0.09°F + 0.02°F/1000 hrs
above 212°F)
Response Time in Water < 4 minutes, typical to 90%
Time Accuracy ±2 minute per month at 25°C (77°F), see Plot B
Operating Environment Air, water, steam, 0 to 100% RH
Operating Temperature Logging: -40° to 125°C (-40° to 257°F)
Launch/Readout: 0° to 50°C (32° to 122°F), per USB specification
Battery Life 3 years typical use, factory replaceable
Memory 64K bytes (43,000 12-bit measurements)
Construction Titanium with O-ring seals and backup rings
Weight 105 g (3.7 oz)
Size 114 x 20.6 mm diameter (4.5 x 0.81 in. diameter)
Depth Rating 11,000 m (36,080 ft)
Vibration Rating Navy spec: NAVMAT P-9492
Environmental Rating IP68
NIST Certificate Available for additional charge; temperature range -30° to 120°C
(-22° to 248°F)
The CE Marking identifies this product as complying with all relevant
directives in the European Union (EU).
Plot A Plot B
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
-40-200 20406080100120
Tem perature (°C)
Accuracy/Resolution(°C)
Accuracy
Resolution
-400
-300
-200
-100
0
100
200
-40 -20 0 20 40 60 80 100 120
Temperature (°C)
Time Base Error (PPM)
-17.3
-13.0
-8.6
-4.3
0.0
4.3
8.6
Time Base Error (Min/Month)
HOBO U12 Deep Ocean
Temperature Logger
U12-015-03
Included Items:
•O-ring replacement kit
(U12-015-03-ORING-KIT),
which includes 4 blue
O-rings, 4 orange backup
rings, and silicone-based
O-ring lube
Required Items:
•HOBOware® Pro 3.2 or
later (go to
www.onsetcomp.com/
hoboware-free-download)
•USB Cable

HOBO U12 Deep Ocean Temperature Logger Manual
1-800-LOGGERS 2 www.onsetcomp.com
Connecting the Logger
To launch or read out the logger, use the USB cable supplied with HOBOware to connect to the computer.
1. Remove the titanium end-cap from the logger by turning it counter-clockwise. If the cap is difficult to turn, place the stem of a small
screwdriver through the hole in the end-cap for better leverage.
2. Plug the large end of the cable into a USB port on the computer, and the small end into the logger as shown in the following diagram.
3. If the logger has never been connected to the computer before, it may take a few seconds for the new hardware to be detected.
4. Open HOBOware and click the Launch icon on the toolbar to set up the logger. Refer to the HOBOware Help for additional details on
launching.
5. After the logger has started logging, you can read it out while it continues to log, stop it manually with the software, or let it record
data until the memory is full. Refer to the HOBOware Help for more details.
6. After the logger is disconnected, reinstall the end-cap. To install the end-cap, press it in until it snaps in place with only the second set
of O-rings showing, and then screw the end-cap into the logger housing. The end-cap must be securely in place with no visible gap
between the housing and the end-cap.
Note: Before opening the end-cap for read out, make sure that the logger is clean and dry. The logger should always be capped when it is
not connected to a computer.
Important: USB communications may not function properly at temperatures below 0°C (32°F) or above 50°C (122°F).
Sample and Internal Event Logging
The logger can record two types of data: samples and internal events. Samples are the sensor measurements recorded at each logging
interval (for example, the temperature every minute). Internal events are independent occurrences triggered by a logger activity.
Examples of events recorded asynchronously during deployment include when the logger is connected to the host, when the battery is
low, and the end of a datafile once the logger is stopped. The logger stores 64K of data, and can record up to 43,000 samples.
Mounting
Use the 6.4 mm (0.25 in.) diameter hole in the end-cap to secure the logger to an object.
Battery Information
Expected battery life varies based on the temperature and the frequency at which the logger is recording data (the logging interval). With
no more than 60 minutes of operation at 125°C (257°F) per day, a new battery will typically last approximately three years with logging
intervals greater than one minute. Deployments in extremely cold or hot temperatures or logging intervals faster than one minute will
significantly reduce battery life.
The logger has the ability to report and log its own battery voltage. If the battery falls below 3.1 V, the logger will record a “bad battery”
event in the datafile. If the datafile contains “bad battery” events, or if logged battery voltage repeatedly falls below 3.3 V, the battery is
failing and the logger should be returned to Onset for battery replacement.
Do not attempt to replace the battery. If the battery needs to be replaced, contact Onset or an Onset Authorized Dealer for factory
replacement battery service.
WARNING: Do not cut open, incinerate, heat above 150°C (302°F), or recharge the lithium battery. The battery may explode if the
logger is exposed to extreme heat or conditions that could damage or destroy the battery case. Do not dispose of the logger or battery in
fire. Do not expose the contents of the battery to water. Dispose of the battery according to local regulations for lithium batteries.
Care and maintenance of the logger
The logger can be permanently damaged by internal corrosion from condensation or foreign matter entering the case. The logger is
shipped with installed Resilon™ O-rings and backup rings. The logger electronics depend on the integrity of the O-ring/backup ring seal
End-cap
Logger
USB Cable

HOBO U12 Deep Ocean Temperature Logger Manual
1-800-LOGGERS (564-4377) • 508-759-9500
www.onsetcomp.com/support/contact
© 2011–2018 Onset Computer Corporation. All rights reserved. Onset, HOBO, and HOBOware are trademarks or
registered trademarks of Onset Computer Corporation. All other trademarks are the property of their respective
companies.
This product has been manufactured by Onset Computer Corporation and in compliance with Onset’s ISO 9001:2015
Quality Management System.
14767-C MAN-U12-015-03
for protection. Because pressure, temperature, and duration of deployment can affect O-rings and backup rings over time, it is important
to inspect the rings before a new deployment. Replace the rings if they are beginning to deform in shape or if you have any doubt about
the integrity of the seal. To replace the rings:
1. Unscrew the end-cap and remove the orange and blue rings. You may need to use a plastic O-ring tool or similar plastic tool to
remove the blue O-rings. Do not use a screwdriver or sharp metal tool as this could damage the O-ring grooves.
2. Clean the two grooves on the end-cap with isopropyl alcohol.
3. Lightly lubricate the blue O-rings with the silicone-based O-ring lube (included).
4. Work one blue O-ring with your fingers or a plastic O-ring tool over the thread into the first O-ring groove and up into the second
O-ring groove (flush with the end-cap flange). Do not use a screwdriver or sharp metal tool as this could damage the O-ring groove or
the O-ring itself.
5. Install the next blue O-ring over the thread and up to the flange that separates the two grooves.
6. Next, install the orange backup rings below each O-ring. The backup rings are “scarf” cut to make them easier to install.
7. Screw the end-cap back onto the logger. Make sure the backup rings are seated properly when the end-cap is screwed into the logger
housing. The end-cap must be securely in place with no visible gap between the housing and the end-cap.
Note: Static electricity may cause the logger to stop logging. To avoid electrostatic discharge, always transport the logger with its end-cap
on, or in an anti-static bag. Ground yourself by touching an unpainted metal surface before handling the logger. For more information,
search for “static discharge” on www.onsetcomp.com.
End-cap with the correct order of O-rings and backup rings
Assembled end-cap
End-cap flange
Backup ring: install in first O-ring groove against O-ring
O-ring: install in first O-ring groove against flange separating two grooves
Backup ring: install in second O-ring groove against O-ring
O-ring: install in second O-ring groove against end-cap flange
First O-ring groove
Second O-ring groove
Thread
Flange separating two grooves