UNISENSE HYDROGEN SENSOR User manual

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HYDROGEN SENSOR USER MANUAL

Hydrogen sensor user manual
Copyright © 2016· Unisense A/S
Version December 2016

HYDROGEN SENSOR USER MANUAL
UNISENSE A/S

TABLE OF CONTENTS
WARRANTY AND LIABILITY...................................................6
CONGRATULATIONS WITH YOUR NEW PRODUCT! ............................7
Support, ordering, and contact information 7
OVERVIEW ...................................................................9
GETTING STARTED .........................................................10
unpacking anew SenSor 10
polarization 10
connecting the microSenSor 10
pre-polarization 10
calibration 11
Hydrogen reading 11
MEASUREMENTS............................................................14
mounting of the SenSorS 14
electrical noiSe 14
interference 15
ADVANCED USE ............................................................16
STORAGE AND MAINTENANCE ..............................................17
cleaning the SenSor 17
REFERENCES ................................................................18
TROUBLE SHOOTING........................................................19

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notice to purchaSer
This product is for research use only. Not for use in human diagnostic
or therapeutic procedures.
warning
Microsensors have very pointed tips and must be handled with care to
avoid personal injury and only by trained personnel.
Unisense A/S recommends users to attend instruction courses to
ensure proper use of the products.
warranty and liability
The Hydrogen sensor is covered by a 90 days limited warranty.
Microsensors are a consumable. Unisense will only replace
dysfunctional sensors if they have been tested according with the
instructions in the manual within 14 days of receipt of the sensor(s).
The warranty does not include repair or replacement necessitated by
accident, neglect, misuse, unauthorized repair, or modification of the
product. In no event will Unisense A/S be liable for any direct, indirect,
consequential or incidental damages, including lost profits, or for any
claim by any third party, arising out of the use, the results of use, or the
inability to use this product.
Unisense mechanical and electronic laboratory instruments must
only be used under normal laboratory conditions in a dry and clean
environment. Unisense assumes no liability for damages on laboratory
instruments due to unintended field use or exposure to dust, humidity
or corrosive environments.
repair or adjuStment
Sensors and electrodes cannot be repaired. Equipment that is not
covered by the warranty will, if possible, be repaired by Unisense A/S
with appropriate charges paid by the customer. In case of return of
equipment please contact us for return authorization.
For further information please see the document General Terms of Sale
and Delivery of Unisense A/S as well as the manuals for the respective
products.
WARRANTY AND LIABILITY

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support, ordering, and contact information
The Hydrogen microsensor is a miniturized sensor for measuring
partial pressure of H2in the micromolar range.
If you wish to order additional products or if you encounter any
problems and need scientific/technical assistance, please do not
hesitate to contact our sales and support team. We will respond
to your inquiry within one working day.
E-mail: [email protected]
Unisense A/S
Tueager 1
DK-8200 Aarhus N, Denmark
Tel: [phone]
Fax: [phone]
Further documentation and support is available at our website
www.unisense.com.
CONGRATULATIONS WITH YOUR NEW PRODUCT!
REPLACEMENT OF SENSORS
Unisense will replace sensors that have been damaged during shipment provided that:
• The sensors were tested immediately upon receipt in accordance with the delivery note
and the manual
• The seal is still intact.
• The sensors are returned to Unisense for inspection within two weeks.
• The sensors are correctly packed for return to Unisense, in accordance with the note
included in the sensor box.

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RECOMMENDED AMPLIFIERS
One-channel amplifier: Microsensor Monometer
Multi-channel amplifiers: Microsensor Multimeter

9
OVERVIEW
The Unisense hydrogen microsensor is designed for research
applications within physiology, biotechnology, environmental sci-
ences, and related areas.
With the minute tip size, excellent response time, and good sen-
sitivity the Unisense hydrogen sensor facilitates reliable and fast
measurements with a high spatial resolution.
The Unisense hydrogen microsensor is a miniaturized Clark-type
hydrogen sensor with an internal reference electrode and a
sensing anode. The sensor must be connected to a high-sensitivity
picoammeter where the anode is polarized against the internal
reference. Driven by the external partial pressure, hydrogen from
the environment will pass through the sensor tip membrane and
will be oxidized at the platinum anode surface. The picoammeter
converts the resulting oxidation current to a signal.
THIS MANUAL COVERS THE UNI-
SENSE HYDROGEN MICROSENSORS
H210 (tip diameter <20 µm)
H225 (tip diameter 20-30µm)
H250 (tip diameter 40-60µm)
H2100 (tip diameter 90-110µm)
H2500 (tip diameter ~500µm)
H2-MR (for use with microrespiration
chambers MR-Ch)
H2-N (Needle type sensor)
H2-spec - Customer specified.
Schematic view of a hydrogen sensor with a LEMO plug.
Sensor tip
LEMO plug
IMPORTANT
Unisense sensors
are neither
intended nor
approved for use in
humans

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GETTING STARTED
unpacking anew sensor
When receiving a new microsensor remove the shock-absorbing
grey plastic net.
polarization
The signal from the hydrogen sensor is generated in picoampere.
Therefore the hydrogen sensor must be connected to a polarizing
picoammeter (e.g. a Microsensor Monometer, a Microsensor Multi-
meter, or Field Microsensor Multimeter).
Hydrogen sensors should be polarized at +1000 mV. The polariza-
tion voltage is set in the amplifier. For details on how to set and
check the polarization, consult the user manual of the picoamme-
ter to be used. If you are using a PA2000 amplifier, please check the
polarization voltage before connecting the sensor, since incorrect
polarization may destroy the sensor.
connecting tHe microsensor
Connect the LEMO connector to the input terminal. The LEMO
connector contains connections for both internal reference elec-
trode and sensing anode.
pre-polarization
Just after connecting the sensor, the signal will be very high and
unstable then drop rapidly over the first few minutes. After that
the signal will drop slowly for up to 1 hour. Therefore, a period
of polarization is necessary before you can use the sensor. This is
called the pre-polarization period.
The signal should stabilize at 0-50 picoampere (on the PA2000, the
sign will be negative since sensor is positively polarized) for
zero hydrogen concentration, depending on the specific sensor. If
the sensor is new or has not been operated for several days, it
WARNING
Do not remove the
seal and protective
plastic tube
before these steps
and calibration
are succesfully
completed.
WARNING
Incorrect
polarization may
destroy the sensor
Sensor tip
LEMO plug
Cable includes guard