HOBO U12 Temp/RH/Light/External Data Logger
2
Operation
A light (LED) on the side of the logger confirms
logger operation.
The following table explains when the logger
blinks during logger operation.
When: The light:
The logger is logging Blinks once every one to four seconds (the
shorter the logging interval, the faster the
light blinks); blinks when logging a sample
The logger is awaiting a start
because it was launched in Start
At Interval, Delayed Start, or
Button Start mode
Blinks once every eight seconds until launch
begins
The button on the logger is
being pushed for a Button Start
launch
Blinks once every second while pressing the
button and then flashes rapidly once you
release the button. The light then reverts to a
blinking pattern based on the logging interval
Using the RH sensor
In order to take humidity measurements, the temperature sensor must be
used in conjunction with the RH sensor.
Conditions outside the recommended range may offset the RH signal.
Vapors may also affect the RH sensor. The diffusion of chemicals into the
sensor may cause a shift in both offset and sensitivity. High levels of
pollutants may cause permanent damage to the sensor.
Upon returning to normal conditions, the RH sensor will slowly return
towards calibration state by itself. However, prolonged exposure to
extreme conditions may accelerate aging and eventually lead to a
permanent shift. To recondition the sensor, do the following:
1. Remove the battery
2. Warm 24 hours 80–90°C (176–194°F) at < 5% RH
3. Re-hydrate 48 hours 20–30°C (70–90°F) at 75–95% RH
Protecting the logger
The logger can be permanently damaged by corrosion if it gets wet.
Protect it from condensation. If it gets wet, remove the battery
immediately and dry the circuit board with a hair dryer before reinstalling
the battery. Do not let the board get too hot. You should be able to
comfortably hold the board in your hand while drying.
Note! Static electricity may cause the logger to stop logging. To avoid
electrostatic discharge, transport the logger in an anti-static bag, and
ground yourself by touching an unpainted metal surface before handling
the logger. For more information about electrostatic discharge, visit
http://www.onsetcomp.com/Support/support.html.
Mounting
There are four ways to mount the logger using the materials in the
mounting kit included with the logger.
•Use the hook and loop tape to affix the
logger to a surface.
•Attach the magnet and then place the logger
on a magnetic surface.
•Use the tie wrap and tie wrap mount to tie
the logger to an object.
•Fasten the logger to a surface with the two
Phillips-head screws. The back of the logger
has two inserts for the screws, 32 mm (1¼
inches) apart.
Battery
The logger requires one 3-Volt CR-2032 lithium battery. Expected battery
life varies based on the temperature and the frequency at which the logger
is recording data (the logging interval). A new battery will typically last
one year with logging intervals greater than one minute. Deployments in
extremely cold or hot temperatures or logging intervals faster than one
minute may significantly reduce battery life.
To replace the battery:
1. Disconnect the logger from the computer.
2. Unscrew the logger case.
3. Lift the circuit board and carefully push the battery out with a small
blunt instrument, or pull it out with your fingernail.
4. Insert a new battery, positive side facing up.
5. Carefully realign the logger case and re-fasten the screws.
WARNING: Do not cut open, incinerate, heat above 85°C
(185°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.
Service and Support
HOBO products are easy to use and reliable. In the unlikely event that you have a problem with
this instrument, contact the company where you bought the logger: Onset or an Onset
Authorized Dealer. Before calling, you can evaluate and often solve the problem if you write
down the events that led to the problem (are you doing anything differently?) and if you visit
the Technical Support section of the Onset web site at www.onsetcomp.com/support.html.
When contacting Onset, ask for technical support and be prepared to provide the product
number and serial number for the logger and software version in question. Also completely
describe the problem or question. The more information you provide, the faster and more
accurately we will be able to respond.
Onset Computer Corporation
470 MacArthur Blvd., Bourne, MA 02532
Mailing: PO Box 3450, Pocasset, MA 02559-3450
Phone: 1-800-LOGGERS (1-800-564-4377) or 508-759-9500
Fax: 508-759-9100
E-mail: loggerhelp@onsetcomp.com
Internet: www.onsetcomp.com
Returning Products to Onset
Direct all warranty claims and repair requests to place of purchase. Before returning a failed
unit, you must obtain a Return Merchandise Authorization (RMA) number from Onset. You
must provide proof that you purchased the Onset product(s) directly from Onset (purchase order
number or Onset invoice number). Onset will issue an RMA number that is valid for 30 days.
You must ship the product(s), properly packaged to protect against further damage, to Onset (at
your expense) with the RMA number marked clearly on the outside of the package. Onset is not
responsible for any package that is returned without a valid RMA number or for the loss of the
package by any shipping company. Products must be clean and free of any contaminants before
they are sent back to Onset or they may be returned to you.
Repair Policy
Products that are returned after the warranty period or that are damaged by the customer as
specified in the warranty provisions can be returned to Onset with a valid RMA number for
evaluation.
Optional Services
Please contact Onset for more information and prices on:
•ASAP Repair. Onset will expedite the repair of a returned product.
•Data-back™ Service. HOBO data loggers store data in nonvolatile EEPROM memory.
Onset will, if possible, recover your data to a disk.
•Tune Up Service. Onset will examine and retest any HOBO data logger.
Warranty
Onset Computer Corporation (“Onset”) warrants to the original end-user Purchaser for a period
of one year from the date of original purchase that the HOBO product(s) purchased will be free
from defect in material and workmanship. During the warranty period Onset will, at its option,
either repair or replace products that prove to be defective in material or workmanship.
This warranty is void if the product has been damaged by the Purchaser as a result of improper
maintenance, abuse, misuse, mishandling, misapplication, error or negligence of Purchaser, or if
there has been an unauthorized alteration, attachment or modification.
THERE ARE NO WARRANTIES BEYOND THE EXPRESSED WARRANTY AS
PROVIDED IN THIS DOCUMENT. IN NO EVENT SHALL ONSET BE LIABLE FOR
LOSS OF PROFITS OR INDIRECT, CONSEQUENTIAL, INCIDENTAL, SPECIAL OR
OTHER SIMILAR DAMAGES ARISING OUT OF ANY BREACH OF THIS
CONTRACT OR OBLIGATIONS UNDER THIS CONTRACT, INCLUDING BREACH
OF WARRANTY, NEGLIGENCE, STRICT LIABILITY, OR ANY OTHER LEGAL
THEORY.
LIMITATION OF LIABILITY. The Purchaser’s sole remedy and the limit of Onset’s
liability for any loss whatsoever shall not exceed the Purchaser’s price of the product(s). The
determination of suitability of products to the specific needs of the Purchaser is solely the
Purchaser’s responsibility. THERE ARE NO WARRANTIES BEYOND THE
EXPRESSED WARRANTY IN THIS DOCUMENT. EXCEPT AS SPECIFICALLY
PROVIDED IN THIS DOCUMENT, THERE ARE NO OTHER WARRANTIES
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO, ANY IMPLIED
WARRANTIES OF MERCHANTIBILITY OR FITNESS FOR A PARTICULAR
PURPOSE. NO INFORMATION OR ADVICE GIVEN BY ONSET, ITS AGENTS OR
EMPLOYEES SHALL CREATE A WARRANTY OR IN ANY WAY INCREASE THE
SCOPE OF THE EXPRESSED WARRANTY OFFERED WITH THE SALE OF THIS
PRODUCT.
INDEMNIFICATION. Products supplied by Onset are not designed, intended, or authorized
for use as components intended for surgical implant or ingestion into the body or other
applications involving life-support, or for any application in which the failure of the Onset-
supplied product could create or contribute to a situation where personal injury or death may
occur. Products supplied by Onset are not designed, intended, or authorized for use in or with
any nuclear installation or activity. Products supplied by Onset are not designed, intended, or
authorized for use in any aeronautical or related application. Should any Onset-supplied product
or equipment be used in any application involving surgical implant or ingestion, life-support, or
where failure of the product could lead to personal injury or death, or should any Onset-
supplied product or equipment be used in or with any nuclear installation or activity, or in or
with any aeronautical or related application or activity, Purchaser will indemnify Onset and
hold Onset harmless from any liability or damage whatsoever arising out of the use of the
product and/or equipment in such manner.
LEGAL REMEDIES. This warranty gives you specific legal rights. You may also have other
rights which vary by jurisdiction. The remedies provided herein are in lieu of all other remedies,
express or implied.
© 2003, 2004 Onset Computer Corporation. All rights reserved.
Part #: MAN-U12-012, Doc #: 7661-B
Onset and HOBO are registered trademarks of Onset Computer Corporation. Other products
and brand names may be trademarks or registered trademarks of their respective owners.
32 mm
(1¼ inch)
Light
Channel 4
external
input
