Hobo H08-006-04 User Manual

Thank you for buying a HOBO data logger. With proper care it will give you years of accurate and

reliable measurements.
This manual covers the HOBO H8 4-Channel External data logger. This logger can store 32,520 time-

stamped measurements and is compatible with the HOBO Shuttle allowing for convenient retrieval of
field data.

Specifications

Operating range (logger): -4°F to +158°F (-20°C to +70°C),

0 - 95% RH non-condensing

Time accuracy: approx. ±1 minute per week (±100 ppm at +68°F or +20°C),

full dependance shown in Plot A

Measurement capacity: 32,520 measurements total, stored in

nonvolatile memory
Drop proof to 5'
Size: 2.4" H x 1.9" W x 0.8" D
Weight: approximately 1 oz.
Battery: CR-2032 (lithium), user-replaceable
Battery life (continuous use): 1 year
Storage temperature: -40°F to +167°F (-40°C to +75°C)

External Sensors - Onset has a range of external temperature and AC
current sensors that are compatible with the HOBO H8 4-Channel External
logger. Measurement specifications for using Onset temperature and AC
current sensors with this logger are provided
in the sensor manuals. For compatible sensors, see the HOBO
catalog, contact Onset Computer Corporation or contact an Onset Authorized
Dealer.

When using multiple voltage inputs, current inputs, or a combination of both
input types; keep in mind that the (-) from your current source(s) and the
(0V) line of your voltage source(s) will be tied together when installed on
the logger. The lines must be at the same voltage potential or inaccurate
readings or even damage to the logger may occur. You must also take into
account that these lines may also be tied to earth ground through your PC
interface cable when connected to your computer. Special precautions may
be necessary if any of your voltage or current source common lines are not
tied to earth ground.

4-20 mA Input cable - This cable (part number CABLE-4-20mA)
measures currents from 0 to 20.1 mA. The accuracy is ±0.1 mA ±3% of
reading. The 4-20 mA cable must be connected such that the current flows
through, and with the proper polarity, as shown in Diagram A. Do not
expose to current above 20 mA or negative current. Do not cut off the end
of the gray cable where it connects to the blue and yellow wires as that
contains the precision resistor required for current measurement.

Voltage Input Cable

The logger's external inputs can accept the voltage input cable (Onset part number CABLE-2.5­STEREO) which allows a voltage to be recorded. This input reads 0 to 2.5 DC volts, with a ±0.1 µA
maximum leakage between measurements and a ±0.4 µA leakage during sensor measurements (5.4 ms
each). The accuracy is ±10 mV ±3% of reading. Input impedance is 10kΩ. The input line should not be
exposed to signals below 0 volts or above 2.5 volts.

Switched 2.5 V Output - This signal can be used to power a
sensor directly or it can also be used to trigger an external
circuit. External sensors should draw no more than 4 mA total
when powered. The switched 2.5 V output switches on about

4.5 ms before the first channel is measured and stays powered
for 11 ms after the last channel is measured, as shown in
Diagram B. The gray bars show the 2 ms periods during which
the HOBO samples the input signals. Diagram B shows the
envelope when all four channels are enabled. For each disabled channel, the envelope is 16.5 ms shorter.

Connecting the Communications Cable and Launching

A Starter Kit, which includes the appropriate PC interface cable and software, is required to
operate your logger. Connect the PC interface cable into the 3.5 mm
jack on the logger, as shown in Diagram C, and into a working
serial port of your computer. Install and start the logger's software.
Select Launch... under Logger on the menu bar and a launch
dialog box will be provided. For a complete explanation on
installing the software and launching your logger, please refer to
the logger software manual.

Continued on next page

Voltage Input Cable Connections

red wire switched 2.5 V output
white wire voltage input
black wire Ground

Plot B

Temperature Accuracy

and Resolution TMC6-HA

(wide accuracy thermister cable)

Plot C

Temperature Accuracy

and Resolution TMC6-HB

(high accuracy thermister cable)

Service and Support

HOBO® products are easy to use and reliable. In the
unlikely event that you have a problem with the
hardware or software, please read the following.

Who do I contact?

Contact the company that you bought the loggers
from: Onset Computer Corporation or an Onset
Authorized Dealer.

Before calling, you can evaluate and often solve
your problem if you try the following:

1. Read this manual and the ReadMe file on the
software disk. It may only take a few moments to
get the answers you need.

2. Write down the events that led to the problem.
Have you changed anything in your computer
recently? Are you doing anything differently?

When contacting Onset Computer
Corporation, please indicate that you need

Technical Support for HOBO® products.

Be prepared to:

1. Provide the product number which is found on
the bottom of the logger, the software version and
serial number if present on the diskette.

2. Provide details on the hardware and software
configuration of your computer including:
manufacturer, model number, peripherals, and
version of operating system.

3. Completely describe the problem or question. The
more information you provide, the faster and more
accurately we will be able to respond.

NOTE: Onset provides technical support to one
person for each software license.

Onset Technical Support

Onset Computer Corporation

470 MacArthur Blvd.

Bourne, MA 02532

Mailing address: PO Box 3450

Pocasset, MA 02559-3450

1-800-LOGGERS (1-800-564-4377)

Phone: [phone]

Fax: [phone]

E-mail: [e-mail]

Warranty

The HOBO® products are warranted to be free
from defects in material and workmanship for a
period of one year from the date of original
purchase. During the warranty period Onset will,
at its option, either repair or replace products
that prove to be defective. This warranty is void
if the Onset products have been damaged by
customer error or negligence or if there has been
an unauthorized modification.

Returning Products to Onset

Direct all warranty claims 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 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. Loggers must be clean and
free of any toxins 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.

Please contact Onset for more information and
prices on:

ASAP Repair Policy

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.

Operation Indication

The HOBO data loggers have a red LED light that blinks while they are
logging. The LED blinks brightly at every measurement, and weakly
every two seconds if the interval between measurements is longer than
two seconds. The blinking LED is located on the front of the logger and
is most visible when viewed straight on, as shown in Diagram C.

Mounting Options

Included with your HOBO H8 data logger are three options for
mounting it on location: a magnet, hook and loop tape, and double-sided
tape. These can be stuck on the back of your HOBO. When using the
magnet, note that it works best on flat surfaces.

Readout

Reconnect the HOBO data logger to the PC interface cable, start the logger software,
select Readout under Logger on the menu bar and the data will be displayed in
graphical or tabular form. For a complete explanation on reading out your logger, please
refer to the logger software manual.

Keep it Dry

Your HOBO data logger can be permanently damaged by corrosion if it gets wet. Protect
it from rain or condensation. Should it get wet, remove the battery immediately and dry
the board completely with a hair dryer before reinstalling the battery.

Changing the Battery

We recommend changing the HOBO's battery when its level is less than 30% (battery
level is displayed on the host computer during Launch, Readout or on the HOBO Shuttle
after data offload). Data stored in the HOBO will not be lost when removing the battery.
To change the battery, open the case as shown in Diagram D, lift the circuit board and
remove the battery by carefully pushing it out with a small screwdriver or other small,
blunt instrument. Be sure to install the battery with the printed side away from the
HOBO’s circuit board as shown in Diagram E. The logger’s LED will blink a number of
times after the battery has been installed. Note: Do not cut open, incinerate, heat

above 185°F (85°C) or recharge lithium battery. Dispose per local regulations.

Continued from other side

Battery

Battery Holder

Diagram E

Diagram D