LogiCO2 O2 User manual

User’s Manual
O2Safety System
NOTE 1: Always test your set, BEFORE INSTALLATION!
The different sets are delivered pre-connected in the package.
Be aware! During the test a very loud sound will be emitted from the horn.
The test procedure is described in chapter 3.1 in this manual.
NOTE 2: Remember to perform a startup calibration when the system is installed.
The calibration procedure is described in chapter 4 in this manual.
English

2
9. Mk9 Central Unit, General information
9.1 General Description
9.2 LED (Light Emitting Diode), buzzer
and display indications
9.3 Mute/reset button
9.4 O2 Alarm
9.5 Test the system
9.6 System fault
9.7 Removal of the Mk9 unit cover
9.8 Mk9 Central Unit, Internal layout
9.9 DIP-switch settings
9.10 DIP-switch settings, Number of
connected sensors
9.11 Mk9 Central Unit, Display information
9.12 Error alarm codes
(shown in Central Unit display)
9.13 Mk9 Central Unit, Warning Sign
9.14 Mk9 Central Unit, Specifications
10. Plug-In Power Supply, Specifications
11. Environmental conditions for the system
12. Service and maintenance
13. Function and installation check
13.1 Power supply control
13.2 Central Unit check
13.3 O2 Values displayed on the Central Unit
13.4 Mk9 O2 Sensor check
13.5 Installation Record
14. Warranty
1. General information on O2-detection
2. General LogiCO2 Safety System description
3. Test and Installation
3.1 Testing set, BEFORE INSTALLATION
3.2 Installation of the O2 sensor
3.3 Installation of the warning horn/strobe
3.4 Installation of the central unit
3.5 Installation and connection of the cables
3.6 Connection of the power supply
4. Calibration, AFTER INSTALLATION
5. Connection diagram
6. What to do in case of an Alarm?
7. Mk9 O2 Sensor, General information
7.1 General Description
7.2 LED (Light Emitting Diode), buzzer
and display indications
7.3 Mk9 O2 Sensor, Internal layout
7.4 DIP-switch settings, ID-address 1-4
7.5 Mk9 O2 Sensor, Display information
7.6 Mk9 O2 Sensor, Specifications
8. Horn/Strobe LED, General information
8.1 General Description
8.2 Horn/Strobe, Warning Sign
8.3 Horn/Strobe LED, Specifications
Index
Explanations of symbols for the O2 Safety System
Please note that whenever installing or disconnecting a system,
refer to this manual first!
Double insulation protected equipment may also be called “Class 2”.
Symbol for the marking of electrical and electronic equipment.
(The symbol indicating separate collection for electrical and
electronic equipment).

3
1. General information on O2-detection
NITROGEN GENERATORS
Please note that if a nitrogen generator is being used in the area where the O2 sensor
is installed, the excess oxygen created by the nitrogen generator must be led out of
the area. It is not allowed to use the O2 sensor in the area if the oxygen is not led out.
The LogiCO2´s O2 Safety Systems measures the O2 concentration in a confined space environment
and provides alerts/alarms in the event that O2 levels in that space reaches the pre-set alarm levels.
The O2 sensing devices uses optical analysis for detection of O2.
If a sensor detects a low or high O2 level, the O2 sensor alerts via sound and light-diodes as well as
remotely connected warning lamps, horns or horn/strobes which will be activated. If it is connected to
our Mk9 central unit it will also display which sensor has detected an alarm O2 level.
First after a self-diagnostics program has been done by the system the sensor will begin to detect O2
levels when powered on. The system is delivered pre-connected. With auxiliary kits, functionality can
be substantially extended. There is a set which is comprised of one O2 sensor, one central unit, one
horn/strobe as well as appropriate signs. As well as one with the Stand alone version.
O2 concentration levels (%) and effects
(%) Effect
20.9 Normal.
19.0 Some unnoticeable adverse physiological effects.
16.0 Increased pulse and breathing rate, impaired thinking and
attention, reduced coordination.
14.0 Abnormal fatigue upon exertion, emotional upset, faulty
coordination, poor judgment.
12.5 Very poor judgment and coordination, impaired respiration
that may cause permanent heart damage, nausea and
vomiting.
<10.0 Inability to move, loss of consciousness, convulsions, death.
Source: Compressed Gas Association, 2001.

4
2. General LogiCO2 Safety System description
LogiCO2´s O2 Safety Systems measure O2 concentration in a confined space environment and
provides alerts/alarms in the event that O2 levels in that space reaches a preset level. The O2 sensing
devices uses an optical sensor for accurate detecting of O2. When installed properly, the system will
continuously monitor the O2 concentration where a O2 sensor is located.
If a sensor detects a low or high O2 level, the O2 sensor alerts via sound and light and remotely
connected warning lamps, horns or horn/strobes will be activated. The central unit will alert with
sound and display which sensor that has detected a low or high O2 level. A properly installed system
will begin to detect O2 levels when powered on, after a self-diagnostics program has been made by
the system. No additional start-up procedure or adjustment is necessary.
The system is delivered as pre-connected sets with auxiliary kits to extend the function of the sets.
The sets are comprised of one or more O2 sensors, with auxiliary central unit/s, horn/s and relay
boxes.
Examples of sets and kits:
O2 Sensors
Sound/Light/Relay
connected to sensors
Control/Visualize
Central Unit
Mk9 O2 set
2056
Mk9 O2 sensor kit
2124

5
3. Test and installation
LEGAL NOTICE
All persons responsible for the operation and maintenance of this equipment must
read and understand the safety and operating information contained in this guide.
Installation and service of this equipment should be performed only by professionals.
The function of the equipment will be impaired if it is not properly installed. Disconnection from
power supply source: when installing the O2 Safety System to the power net, please ensure
that the fuse that the system runs on is clearly marked. This makes it easy to disconnect the
power to the system, if needed.
It is very important to be aware that the O2 Safety System does not function if disconnected
from power mains.
3.1 Testing set, BEFORE INSTALLATION
The different sets are delivered pre-connected in the package. Always test the set before installation
to verify proper function! NOTE: Be aware that during the test a very loud sound will be emitted from
the horn.
1. Open the box and carefully take the components out of the package.
2. Find the power supply in the package and attach the correct mains-adaptor for your
country’s outlet, then connect the power supply to the electrical outlet. The set should
now activate.
3. If you test a Mk9 detector set, please check that all LEDs on the central unit and the
sensors illuminate and the built-in buzzers beep, this is part of the self-diagnostics
program. Approximately 3 seconds after connection all external horns and/or strobes
(connected to the sensor) should be activated for approximately 5 seconds.
4. Now your set is tested and you can start the installation.
Note! If additional kits are to be installed. Please check appropriate part of the manual
for correct DIP-switch setting (ID-address).

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3.2 Installation of the O2 Sensor
Correct placement of the O2 Sensor
The O2 sensor should be placed in the room where there is a risk for unsafe oxygen concentration –
this would be at the distribution points of the nitrogen, nitrogen generator or nitrogen tank as well as
mixed gas with nitrogen. Please observe, this does not necessarily have to be where the asphyxiant
gas is stored, for example when it is stored outside and the gas is routed into the building via pipes.
It is also VERY IMPORTANT to be aware that the danger always is relative to how much asphyxiant
gas is used and stored in relationship to the volume of the room in question.
NOTE: If the room has only mechanical ventilation, it should have a sensor.
Installation of the O2 Sensor
The O2 sensor should be installed at breathing height, between 150-180 cm/5-6 feet from the floor.
Try to find an installation position where the unit is least likely to be damaged. Mount the O2 sensor
with supplied mounting screws.
150-
180 cm
/5-6 ft

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3.3 Installation of the Horn/Strobe
1. The horn/strobe/s must be installed on the wall above the O2 sensor, approximately 2-2.4
m/80-96 inches (as per NFPA 72) above the floor, clearly visible from any entrance of the area
being monitored. It is recommended that a second horn/strobe be placed OUTSIDE the area being
monitored, preferably placed over the door/s leading to the monitored area. This will require more
than one horn/strobe. Mount the unit with supplied mounting screws.
2. Mount the included warning signs so they are clearly visible, next to or above the horn/strobes, in a
permanent way.
3.4 Installation of the Central Unit
1. If your set includes a central unit, it must be installed outside the area or room being monitored, for
example on a wall in the manager’s office. The central unit must be installed at a clearly visible and
reachable height.
2. Mount the included information signs clearly visible, next to or above the units, in a permanent way.
2-2.4 m
/ 80-96"

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3.5 Installation and connection of the cables
The different units are connected to each other by cables. The blue marked cable is used for
signalisation (horn/strobe, warning beacon and remote control box). The red marked cable is for
communication and power. Please observe, all cables have splitters at the end to facilitate extended
cable lengths. When installing, the cables may need to be disconnected for purposes of cable routing.
When reconnecting, please make sure that you connect to the original splitters and connectors. Make
sure to mount the protective collar seals with the tie-wraps in order to protect the connections from
dirt and water. The collar seals as well as the tie-wraps are also delivered in the box that the sensor
comes in. If possible, route the cables through cable conduits between the units, for a neat and safe
installation.
Protective collar seals and cable ties are included. They must be used as below to protect the RJ45 1-1
connector or RJ45 1-2 splitter from moisture and dust.
3.6 Connection of the power supply
A separate power supply (100-240 VAC) supplies power to the system. Please observe that you have
to connect the appropriate plug adaptor to the power supply depending on which country you are in.
Connect the power supply to the electrical outlet.
Mount the included plug-lock so that the power supply cannot be
disconnected without the use of tools.
It is also possible to order a hardwired power supply option when
and were it is needed.
Blue
Red

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4. Calibration, AFTER INSTALLATION
Startup calibration
When the system has been installed, it is important to do a calibration since the sensor could have
become uncalibrated during transportation.
The sensor needs to be powered for at least 20 minutes before the calibration can be done, to
make sure it is heated up and adjusted to the environment. Try to make sure that the room is well
ventilated.
Instruction:
A more detailed instruction can be found in chapter 7.5, ”Service Mode Three”, in this manual.
1. Press and hold the button on the sensor for 10 seconds.
2. When the asterisk (*) in the upper right corner of the display is lit, push the button
shortly. Repeat this five times in a row to enter the Calibration mode. For each correct
push of the button, a dot will be lit in the lower left corner. If an incorrect push happens,
the procedure starts over again.
3. The instructions in the display will say Push the button to start calibration. Push the
button short and a 90 second timer starts counting down. If the calibration is successful,
the display will show “Calibration OK” and go back to Service Mode One, for 30 seconds,
and then go to “normal view”.
Automatic calibration - Activated or deactivated
The LogiCO2 O2 sensor has an automatic self calibration function activated as standard, so after the
first start up calibration, no further manual calibrations should be needed in normal conditions.
However, if the O2 Sensor is used in an area that can have an abnormally high O2 concentration, the
AUTO-CAL must be deactivated by setting the DIP-switch number 6 (on the printed circuit board) in
up position. If you wish to use the alarm function for high levels of O2, for example an alarm at 23%,
the automatic calibration does also need to be deactivated.
If you have deactivated the automatic calibration, manual calibrations will need to be done at least
every 6 months if the sensor is installed in an normal environment.
If the sensor is installed in a rough environment, calibrations might need to be done more often. The
manual calibration procedure is the same as the ”startup calibration” procedure.

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5. Connection diagram
This connection diagram shows an example of how the system can be installed.
Please note:
A separate installation manual is provided with each extra O2 sensor kit explaining the simple
installation process for adding additional sensors to an existing set.
Mk9 Central Unit
Remote Connection Box
Horn/Strobe
Power Supply
RJ45 Splitter (red)
1-1/1-2/1-4
RJ45 Splitter (blue)
1-1/1-2/1-4
Mk9
Mk9
k9
9
C
Ce
Ce
Ce
Ce
Ce
t
ntr
ntr
ntr
ntr
al
l
al
al
al
a
Uni
Un
U
U
t
Rem
ote
Co
nne
cti
on
Box
Horn/Stro
be
P
P
P
Pow
Pow
ow
w
w
er
er
er
er
Sup
up
Sup
Sup
Sup
Su
ply
ply
ly
y
ply
ply
p
p
R
J45 S
pli
li
tt
tte
r
(
red
)
1
-1
/
1-2
/
1-4
RJ45 S
pli
pli
pli
tte
tte
tt
r (
blue)
1-1
1
1
1
/
/1
/1-
/1-
/1-
1
2/1
2/1
/1
1
1
2/
2
-4
-
-
Possibility to expand with up
to four Mk9 O2 Sensors or up
to eight Mk9/Mk10/Mk90
CO2 Sensors
SIGNCO2SENSOR MK90 EN
ExplanationIndication
Unitin operation.GreenLED
CO2sensor fault. The display on the CO2 sensor will show “Error”.
CallService.
Low-Alarm(High ambient CO2 concentration level) or TWAAlarm (5000 ppm/8 h Time
WeightedAverage). The display on the CO2 sensor will show “Alarm” or “TWA HighAlarm”.
Connectedremote warning strobe will be activated. Call Service.
High-Alarm(Dangerously high ambient CO2 concentration level). The display on the CO2
sensorwill show “High-Alarm”. The sensor will start flashing and connected remote warning
hornand strobe will be activated. Call Fire Departement.
CO2Awareness indication. The CO2 level is over 5000 ppm. No danger - but the CO2 is
unnaturallyhigh. The display on the CO2 sensor will show “High”.
YellowLED
RedLED
RedLED
RedLED
CO2ALERT
CAUTION!
CO2Sensor: Do not cover or place anything
in front of or on top of the sensor.
!
-5 sec -
Altitudeset to:
Doneby:
SIGNCO2SENSOR MK90 EN
ExplanationIndication
Unitin operation.GreenLED
CO2sensor fault. The display on the CO2 sensor will show “Error”.
CallService.
Low-Alarm(High ambient CO2 concentration level) or TWAAlarm (5000 ppm/8 h Time
WeightedAverage). The display on the CO2 sensor will show “Alarm” or “TWA HighAlarm”.
Connectedremote warning strobe will be activated. Call Service.
High-Alarm(Dangerously high ambient CO2 concentration level). The display on the CO2
sensorwill show “High-Alarm”. The sensor will start flashing and connected remote warning
hornand strobe will be activated. Call Fire Departement.
CO2Awareness indication. The CO2 level is over 5000 ppm. No danger - but the CO2 is
unnaturallyhigh. The display on the CO2 sensor will show “High”.
YellowLED
RedLED
RedLED
RedLED
CO2ALERT
CAUTION!
CO2Sensor: Do not cover or place anything
in front of or on top of the sensor.
!
-5 sec -
Altitudeset to:
Doneby:
Mk9 CO2 Sensor
Mk9 O2 Sensor
Mk90 CO2 Sensor
WARNING
! !
Confined Space
Risk for Asphyxiation
DO NOT ENTER THIS AREA WHEN SIREN
IS SOUNDING AND LIGHT IS FLASHING!
Emergency Actions
• Evacuate the Area Immediately.
• Call the Fire Department from
outside of the building.
Risk for
Low Oxygen
Level
Blue Light
Power ON
SIGNO2H/S B EN
WARNING
! !
Confined Space
Risk for Asphyxiation
DO NOT ENTER THIS AREA WHEN SIREN
IS SOUNDING AND LIGHT IS FLASHING!
Emergency Actions
• Evacuate the Area Immediately.
• Call the Fire Department from
outside of the building.
Risk for
Low Oxygen
Level
Blue Light
Power ON
SIGNO2H/S B EN
INDICATION CAUSE ACTION
CentralUnit:
• The red diode is ON
• Constant sound si gnal
Display:
• Sensor number, O2 % and
GatewayAla rm A
ALARM
!
TAKE PR ECAUTI ONS
Lowconcentration of O2
DONOT ENTER
therisk zone.
Evacuatethe area if
O2level is under 19.5%.
CentralUnit:
• The yellow diode is blinking
• Beeping sound signal
Display:
• Sensor number, (Fault
information)
SYSTEMFAULT Check the manual, communication
cablesand O2-Sensor.
Ifno fault is found, call service.
Phone:.....................................
Afteran alarm, always reset
thesystem. ALARM RESET
ALARM TEST Press reset button until ”Testing
system...”is shown in the display.
Sensor Place
1
2
3
4
O2 Safety System - Mk9
What to do in case of an ALARM?
1. Keep Calm!
2. Turn off the sounding alarm on the Central Unit by pressing the RESET button onthefront.
3. Check the type of alarm and which Sensor is giving the alarm by following the instructions below.
SIGNO2C- U MK9 EN
Pressres et button until ”Alarm
cleared”is shown in the display.
Testthe alarm to insure that
communication,warning lamps
andsounders function.

11
6. What to do in case of an Alarm?
INDICATION CAUSE ACTION
Central Unit:
• The red diode is ON
• Constant sound signal
Display:
• Sensor number, O2 % and
Gateway Alarm A
ALARM!
TAKE PRECAUTIONS
Low concentration of O2
DO NOT ENTER the risk zone.
Evacuate the area if O2 level is
under 19.5%.
Central Unit:
• The yellow diode is blinking
• Beeping sound signal
Display:
• Sensor number,
(Fault information)
SYSTEM FAULT Check the manual,
communication cables and
O2-Sensor.
If no fault is found, call service.
After an alarm, always reset
the system.
ALARM RESET Press reset button on Central
Unit until ”Alarm cleared!”
is shown in the display
Test the alarm to insure that
communication, warning lamps
and sounders function.
ALARM TEST Press reset button on Central
Unit until ”Testing system”
is shown in the display

12
7. Mk9 O2 Sensor, General information
7.1 General Description
The sensor is an O2 sensor with display that is used to monitor the O2 levels of a confined space.
This unit can be connected to a Central Unit or to an existing Mk9 CO2 System for full functionality.
Horn/strobes, flash units or external connection boxes can also be connected to the sensor for added
functionality. The O2 sensor display shows the current O2 level and the current alarm settings.
The LogiCO2 oxygen sensor (O2) has a FBO oxygen sensor with built-in temperature and pressure
adjustment. This means that it has an automatic altitude compansation function. The oxygen sensor
is factory calibrated and measures the ambient oxygen partial pressure (ppO₂) levels. The sensor
benefits from low power operation and a long lifetime (> 5 years) due to the non-depleting sensing
principle.
The O2-sensor is compatible with LogiCO2 Mk9 CO2 Safety System. It communicates via Modbus RTU
with the LogiCO2 Mk9 Central unit and can be used together with the different LogiCO2 CO2 sensors.
The unit is delivered together with a horn and strobe alarm device.
System Fault LED
(Yellow)
O2 Alarm LED
(Red)
Buzzer
Power On LED
(Green)
Display
Service Button

13
7.2 LED (Light Emitting Diode), buzzer and display indications
Indication Explanation
Green LED on Unit in operation
Red LED on and
constant sound signal
Alarm. Ambient O2 concentration level is under or over the alarm
settings. The display on the O2 sensor will show the current O2 level and
the information text: “EVACUATE AREA: Very critical O2 level!”.
If the O2 level is under 19.5%, evacuate the area.
The Central Unit will emit constant sound signal and the digital display
will show “Gateway Alarm A”. Connected remote horns/strobes will be
activated.
Yellow LED on and
intermittent audible
tone
Error. The display on the O2 sensor will show “Sensor error” or “System
error”, together with an information text.
A beeping tone will be made by the Central Unit. The error will be
described in the display of the Central Unit until the fault has been
rectified and cleared/reset on the Central Unit.

14
7.3 Mk9 O2 Sensor, Internal layout
O2 Sensor Function/Indication
1. DIP-switch ID settings
2. LED yellow Fault
3. LED red Alarm
4. LED green Power ON
5. Buzzer High-Alarm
6. Display Measurement and alarm information
7. O2 Sensor O2 measurement sensor
8. RJ45 input connector Power and communication (red connector)
9. RJ45 output connector Alarm outputs (blue connector)
1
5
7
6
89
2
3
4
ON
1 2 3 4 5 6 7

15
7.4 Mk9 O2 Sensor, DIP-switch settings
ID-address 1-4:
ID- address Dip1 Dip2
ID1 OFF OFF
1 2 3 4 5 6 7
ID2 ON OFF
1 2 3 4 5 6 7
ID3 OFF ON
1 2 3 4 5 6 7
ID4 ON ON
1 2 3 4 5 6 7
Alarm levels:
Alarm level Dip3 Dip4 Dip5
A-ALARM: <19.5% >23.0%
B-ALARM: <19.5% >23.0%
OFF OFF OFF
1 2 3 4 5 6 7
A-ALARM: <18.0% >23.0%
B-ALARM: <19.5% >23.0%
ON OFF OFF
1 2 3 4 5 6 7
A-ALARM: <18.0% >23.0%
B-ALARM: <18.0% >23.0%
OFF ON OFF
1 2 3 4 5 6 7
A-ALARM: >23.0%
B-ALARM: >23.0%
ON ON OFF
1 2 3 4 5 6 7
A-ALARM: <19.5%
B-ALARM: <19.5%
OFF OFF ON
1 2
3
4
5
6
7
A-ALARM: <18.0%
B-ALARM: <19.5%
ON OFF ON
1 2
3
4
5
6
7
A-ALARM: <18.0%
B-ALARM: <18.0%
OFF ON ON
1 2 3 4 5 6 7
A-ALARM: PC-software settings
B-ALARM: PC-software settings
ON ON ON
1 2 3 4 5 6 7
Automatic background calibration:
Automatic background calibration Dip6 Dip7
AUTO-CAL activated
Default setting
OFF OFF
1 2 3 4 5 6 7
AUTO-CAL deactivated ON OFF
1 2 3 4 5 6 7

16
7.5 Mk9 O2 Sensor, Display information
Display information during start-up:
Start-up software version Start-up test
LogiCO2 O2 Gateway
FW: 1608
ID: 1
Testing system...
Display information during no alarm mode:
Operation O2 concentration Normal view
O2 Level: 20.6%
A-ALARM: <19.5% >23.0%
B-ALARM: <19.5% >23.0%
AUTO-CAL ON
In normal view, the displays shows:
The current O2 concentration in %. Also, the A-ALARM trig
level and the B-ALARM trig level. These levels can be the same
depending on the setting. The A-ALARM activates the audible
(Horn) alarm device and the B-ALARM activates the optical
(Strobe) alarm device.
Display information during alarm mode:
O2 High-Alarm
O2 Level: 19.4%
A-ALARM: <19.5% >23.0%
B-ALARM: <19.5% >23.0%
EVACUATE AREA: Very crit...*
* Information text is only shown during alarm or error situations.
Display information during error/fault mode:
Error/Fault
O2 Level: 20.6%
”Sensor error”
A-ALARM: <19.5% >23.0%
B-ALARM: <19.5% >23.0%
Information text...*
* Information text is only shown during alarm or error situations.

17
Display information - The service buttons three functions:
1. Service Mode One
O 02017.1
T +24.1
P 1026
% 020.66
e 0000
Up-time: 1568h
Cal-time: 287h
CAL 0.00% (OFF)
One short push:
a. Reading of sensor element data, total run-time of the
O2-sensor, time since the last Calibration and readout of
the correction factor (CAL) for the automatic background
calibration (AUTO-CAL) function – if AUTO-CAL is activated.
b. To return to “normal display view”, push the button short or
wait for 30 seconds.
2. Service Mode Two
O 02017.1
T +24.1
P 1026
% 020.66
e 0000
Up-time: 1568h
Cal-time: 287h
CAL 0.00% (OFF)
*In the “normal display view” push and hold the button for 10
seconds:
a. Reset of the correction factor (CAL. RESET!) for the
automatic background calibration (ABC) function – if ABC is
activated. Release the button.
b. To return to “normal display view”, wait for 30 seconds.
c. In this mode it is possible to go to Service Mode Three.
3. Service Mode Three
Entering Service Mode Three
O 02017.1
T +24.1
P 1026
% 020.66
e 0000
Up-time: 1568h
Cal-time: 287h
...
*
Service Mode Three
Calibration
Press the button to start
the calibration
Service Mode Three calibration
Calibration
Executing calibration
Calibration*: In the “normal display view”, push and hold the
button for 10 seconds:
a. When the asterisk (*) in the upper right corner of the display
is lit, push the button shortly. Repeat this five times in a row
to enter the Calibration mode. For each correct push of the
button, a dot will be lit in the lower left corner. If an incorrect
push happens, the procedure starts over again. The reason
for this advanced way to enter the Calibration is to avoid
unintentional calibration.
b. If no further actions is performed for 1 minute, in Calibration
mode, the O2 Sensor will go back to Service Mode One.
c. The instructions in the display will say Push the button to
start the calibration. Push the button short and a 90 second
timer starts counting down. If the calibration is successful,
the display will show “Calibration OK” and go back to Service
Mode One, for 30 seconds, and then go to “normal view”.
If the display says “Calibration Error”, try to ventilate the room
more and make a new calibration. If the calibration still fails,
replace the O2-sensor.
* Calibration - Only to be performed by trained and certified service personnel.

18
7.6 Mk9 O2 Sensor, Specifications
Power supply: 24V DC
Power consumption: <30 mA
Wiring connections: RJ 45
Digital interface: RS485 serial port MODBUS
Outputs: 2 x transistor output 24V DC, Min 1 mA
Display: Graphical 128x64, backlit
Acoustic signal-strength: 76 dBa (1m) max.
Operating principle: FB-optical
O2 measuring range: 0-25 Vol.%
Accuracy O2: <2% FC
Ambient temperature: -20 to +50°C (-4 to +122°F). Only for indoor use.
LED indications
Green: Operation
Yellow: Fault
Red: Alarm (<19.5% O2)
Sound indications
Beeping: Fault
Continuous: Alarm
Approvals: Tested in accordance with DIN6653-2, applied to
O2sensors.
Dimensions (LxWxD): 90 x 161 x 38 mm / 3.5” x 6.3” x 1.5”
Ingress protection: IP54
Please observe that since this is a safety product we recommend that a function control
should be carried out at least once a year. For more information see chapter 9.5 “Test the system”
and chapter 4 “Calibration”.

19
8. Horn/Strobe LED, General information
8.1 General Description
The horn/strobe is equipped with a pre-wired cable for connection to the O2 Safety System. The
horn/strobe is power supplied from the O2 sensor. Horn/Strobe LED is a loud warning horn (110 dB/1
m) and high intensity strobe (115 cd).
8.2 Horn/Strobe, Warning Sign
The sign for the horn/strobe should be mounted in a permanent way next to the unit.
8.3 Horn/Strobe LED, Specifications
Nominal voltage: 18-24V DC
Average current: 120 mA @ 24V DC supply
Decibel: 110 dB / 1 m (High-Alarm)
Flash intensity: 115 cd (Low-Alarm)
Flash frequency: 65/min
Ambient temperature: -5°C to +50°C (+23°F to +122°F)
Dimensions (LxWxD): 134 x 115 x 61 mm / 5.3” x 4.5” x 2.4”
Ingress protection: IP65
WARNING
! !
Confined Space
Risk for Asphyxiation
DO NOT ENTER THIS AREA WHEN SIREN
IS SOUNDING AND LIGHT IS FLASHING!
Emergency Actions
• Evacuate the Area Immediately.
• Call the Fire Department from
outside of the building.
Risk for
Low Oxygen
Level
Blue Light
Power ON
SIGN O2 H/S B EN
Horn
Strobe
Cable connector

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9. Mk9 Central Unit, General information
9.1 General Description
The Central Unit has a display that is used to monitor and control a O2 Safety System with up to
four sensors. The central unit is multi-lingual and it displays information text for all alarm and error
conditions. It also displays the O2 values of all connected O2 sensors, indicating which sensor the
value comes from. The central unit has an alarm memory that remembers and reactivates any
alarm after a power interruption.
9.2 LED (Light Emitting Diode), buzzer and display indications
Indication Explanation
Green LED on Unit in operation
Red LED on and constant
sound signal
Alarm. Ambient O2 concentration level is under or over the alarm
settings. The display will show “Gateway Alarm A”, indicating which
sensor the alarm comes from. Connected remote horn/strobes will
be activated.
If the O2 level is under 19.5%, evacuate the area.
Yellow LED on and
intermittent audible tone
System fault. The error will be described in the display until the fault
has been rectified and cleared/reset on the central unit.
System Fault LED
(Yellow)
O2 Alarm LED
(Red)
Power on LED
(Green)
Display
Reset Button
Buzzer