BÜNOx 2+
1 Introduction
This quick guide will assist you in starting up the unit. Follow
the safety notices or injury to health or property damage may
occur. Carefully read the original operating instructions in-
cluding information on maintenance and troubleshooting
prior to startup. These are located on the included CD and on-
line at
Please direct any questions to:
Bühler Technologies GmbH
Harkortstraße 29
40880 Ratingen
Germany
Tel.: +49 (0) 21 02 / 49 89-0
Fax: +49 (0) 21 02 / 49 89-20
These operating instructions are a part of the equipment. The
manufacturer reserves the right to change performance-, spe-
cification- or technical data without prior notice. Please keep
these instructions for future reference.
1.1 Intended Use
Burning fossil fuels in most cases requires monitoring the ac-
crued nitric oxides by law.
BÜNOx converters are suitable for use in gas analysis systems
for industrial applications. It allows for easy and cost-efficient
detection of significant NOx components (NO
x
= NO + NO
2
) in
waste gas. Using exchangeable reactor cartridges the unit
converts 100 % of the NO
2
content of sample gas to NO. This al-
lows for cost-efficient direct measurement of the gas compon-
ent NO
x
= NO + NO
2
and indirect measurement of NO
2
using
conventional IR analysers.
One should generally note the BÜNOx converter is intended
for "cold gas conversion" (inlet dew point < 10 °C).
1.2 Improper use
The converters must not be used
• if failure or malfunction thereof jeopardises the safety
and health of individuals.
• in explosive areas,
• to pass flammable or explosive gasses, as well as
• at a sample gas dew point (inlet dew point) > 10 °C.
1.3 Contents
• Converter
• Product documentation
• Connection-/mounting accessories (optional)
2 Safety instructions
The equipment must be installed by a professional familiar
with the safety requirements and risks.
Be sure to observe the safety regulations and generally applic-
able rules of technology relevant for the installation site. Pre-
vent malfunctions and avoid personal injuries and property
damage.
The operator of the system must ensure:
• Safety notices and operating instructions are available
and observed,
• The respective national accident prevention regulations
are observed,
• The permissible data and operational conditions are
maintained,
• Safety guards are used and mandatory maintenance is
performed,
• Legal regulations are observed during disposal,
• compliance with national installation regulations.
DANGER
Electric voltage
Risk of electric shock
a) Disconnect all poles of the unit from the mains for any
maintenance on electric components.
b) Secure the equipment from accidental restarting.
c) The unit may only be opened by trained, competent per-
sonnel.
d) Ensure the correct voltages supply.
DANGER
Toxic, corrosive gases
The measuring gas led through the equipment can be hazard-
ous when breathing or touching it.
a) Check tightness of the measuring system before putting
it into operation.
b) Take care that harmful gases are exhausted to a save
place.
c) Before maintenance turn off the gas supply and make
sure that it cannot be turned on unintentionally.
d) Protect yourself during maintenance against toxic / cor-
rosive gases. Use suitable protective equipment.
DANGER
Potentially explosive atmosphere
Explosion hazard if used in hazardous areas.
The device is not suitable for operation in hazardous areas
with potentially explosive atmospheres.
Do not expose the device to combustible or explosive gas mix-
tures.
3 Technical description
The gas converter BÜNOx 2+ allows for detection of significant
NO
x
components (NO + NO
2
). Sample gas is passed through
the exchangeable gas reactor cartridge for this purpose. A well
thermally insulated tubular furnace holding the exchange-
able reactor cartridge is located inside the housing. The spe-
cial tubular furnace closure with cartridge holder allowing for
quick and easy reactor cartridge changes is located on the
front panel.
The tubular furnace temperature can be adjusted via the
front panel keyboard for the controller. Please note the op-
timal Operating temperatures of the different cartridges:
11
Bühler Technologies GmbH
BX550019 ◦ 02/2020
