MSR ELECTRONIC PolyGard 2 SC2 User manual

INTEC Controls | 12700 Stowe Drive, Suite 100, Poway, CA 92064 | Ph: [phone] & (888) GO.INTEC | inteccontrols.com
September 07, 2022 – Revision
Toxic (E-), Combustible (P-) and Infrared (I-CO2) Gases
PolyGard®2 SC2 & AT6 Sensors
User Manual
May 2022

This page intentionally left blank

Table of Contents
1 General................................................................................................................................... 5
1.1 Intended Use...........................................................................................................................................5
1.2 Safety........................................................................................................................................................5
1.3 Installers‘ and Operators‘ Responsibilities......................................................................................5
1.4 Services ....................................................................................................................................................6
1.5 Limited Warranty ...................................................................................................................................6
1.6 Part Disposal ...........................................................................................................................................6
2 Functional Description ........................................................................................................... 6
2.1 General .....................................................................................................................................................6
2.2 Measuring Mode.....................................................................................................................................6
2.3 Special Mode...........................................................................................................................................6
2.4 Sensor Element.......................................................................................................................................7
A: Catalytic Sensor Element (Pellistor) for Combustible Gases ...............................................7
B: Electrochemical Sensor Element for Toxic Gases and Oxygen ............................................7
C: Semiconductor Sensor Element for Freon Gases, Ethylene and Ammonia.......................8
D: Infrared Sensor Element for Methane, Propane and Carbon Dioxide................................8
3 Installation ............................................................................................................................. 9
3.1 Mounting Instructions...........................................................................................................................9
3.2 Mounting of Sensors .......................................................................................................................... 10
4 Electrical Connection ........................................................................................................... 11
4.1 Plug Connection (SC2) in DT6, DC6, SGC6, SCM6 ....................................................................... 11
4.2 Terminal Connection (AT6)............................................................................................................... 11
4.3 Registration of the Sensors SC2/AT6............................................................................................. 11
5 Commissioning..................................................................................................................... 12
5.1 General .................................................................................................................................................. 12
5.2 Required Instruments for Commissioning (Calibration)............................................................ 12
6 Calibration............................................................................................................................ 12
6.1 Run-in Time .......................................................................................................................................... 13
6.2 Calibration Work ................................................................................................................................. 14
6.2.1 Zero Calibration.................................................................................................................... 14
6.2.2 Gain Calibration.................................................................................................................... 14
6.2.3 Calibration (Gain) with Surrogate Gas for Catalytic Sensor Element (Pellistor)... 15
6.2.4 Extended Calibration for Semiconductor Sensor Element ........................................ 15
6.3 Calibration Analog Output................................................................................................................ 15
6.4 Exchange of Sensors .......................................................................................................................... 16
6.4.1 Sensor SC2............................................................................................................................. 16
6.4.2 Sensor AT6............................................................................................................................. 16
6.4.3 Perform Function Test......................................................................................................... 16
INTEC Controls | 12700 Stowe Drive, Suite 100, Poway, CA 92064 | Ph: [phone] & (888) GO.INTEC | inteccontrols.com
Specifications subject to change without notice. | GA_MC2_SC2_E, 2022-05-31 | USA 220907 | Page 3of 28
SC2-AT6 – UserManual

7 Inspection and Service.......................................................................................................... 17
7.1 Inspection ............................................................................................................................................. 17
7.2 Service and Calibration ..................................................................................................................... 17
8 Troubleshooting................................................................................................................... 18
8.1 Indications for the SC2 ...................................................................................................................... 18
8.2 Indications for the AT6 ...................................................................................................................... 18
9 Specifications....................................................................................................................... 18
9.1 General .................................................................................................................................................. 18
9.2 Digital Sensor SC2 .............................................................................................................................. 19
9.3 Analog Sensor AT6.............................................................................................................................. 19
9.4 Sensor Element.................................................................................................................................... 20
A: Catalytic Sensor Element (Pellistor) for Combustible Gases ............................................ 20
B: Electrochemical Sensor Element for Toxic Gases and Oxygen ......................................... 20
C: Semiconductor Sensor Element for Freon Gases, Ethylene and Ammonia.................... 23
D: Infrared Sensor Element for Methane, Propane and Carbon Dioxide............................. 24
10 Figures.................................................................................................................................. 25
List of Abbreviations .............................................................................................................. 26
Glossary..................................................................................................................................... 27
Revision List............................................................................................................................. 27
INTEC Controls | 12700 Stowe Drive, Suite 100, Poway, CA 92064 | Ph: [phone] & (888) GO.INTEC | inteccontrols.com
Specifications subject to change without notice. | GA_MC2_SC2_E, 2022-05-31 | USA 220907 | Page 4of 28
SC2-AT6 – UserManual

1 General
It is important to read this user manual thoroughly and clearly in order to understand the information
and instructions. The PolyGard®2 devices must be used within product specification capabilities.
Due to on-going product development, MSR-Electronic GmbH | INTEC Controls reserves the right to
change specifications without notice. The information contained herein is based upon data
considered to be accurate. However, no guarantee is expressed or implied regarding the accuracy
of these data.
1.1 Intended Use
The PolyGard®2 sensors are designed for the measurement of combustible, toxic gases and oxygen
as well as of refrigerants.
The digital PolyGard®2 SC2 sensor can only be operated in conjunction with the sensor boards on
DT6, DC6, SGC6, and SCM6 of the PolyGard®2 series, as the SC2 sensor is supplied with 5 V DC
by the sensor board and the data is transmitted digitally to the sensor boards via the local
bus. The SC2 is mounted on the housing of the sensor board.
The analog PolyGard®2 AT6 sensor is operated with 24 V DC and outputs an analog 4–20 mA stand-
ard signal. The individual AT6 sensor head can be mounted on all sensor boards with analog
input, or remotely on its own housing.
The PolyGard®2 sensors must not be used in potentially explosive atmospheres. The sensor must
only be employed in areas within the environmental conditions as specified in the Technical Data.
1.2 Safety
The operating instructions must be carefully read and followed by all persons who install, use,
maintain and check the product. The product can only fulfil its intended functions if it is installed,
used, maintained, serviced and checked in accordance with the instructions provided by MSR-
Electronic GmbH | INTEC Controls.
1.3 Installers‘ and Operators‘ Responsibilities
It is the installer’s responsibility to ensure that all PolyGard®2 devices are installed in compliance
with all national and local codes and OSHA requirements. Installation should be implemented only
by technicians familiar with proper installation techniques and with codes, standards and proper
safety procedures for control installations and the latest edition of the National Electrical Code
(ANSI/NFPA70).
The equipotential bonding required (also e.g. secondary potential to earth) or grounding measures
must be carried out in accordance with the respective project requirements. It is important to ensure
that no ground loops are formed to avoid unwanted interference in the electronic measuring
equip-ment.
It is also essential to follow strictly all instructions as provided in the user manual.
INTEC Controls | 12700 Stowe Drive, Suite 100, Poway, CA 92064 | Ph: [phone] & (888) GO.INTEC | inteccontrols.com
Specifications subject to change without notice. | GA_MC2_SC2_E, 2022-05-31 | USA 220907 | Page 5of 28
SC2-AT6 – UserManual

1.4 Services
It is recommended to check the PolyGard®2 devices regularly. Due to regular maintenance any per-
formance deviations may easily be corrected. Re-calibration and part replacement in the field may
be implemented by a qualified technician and with the appropriate tools. Alternatively, the easily
removable plug-in sensor with the sensor element may be returned for service to INTEC Controls.
1.5 Limited Warranty
MSR-Electronic GmbH | INTEC Controls warrants the PolyGard®2 sensors for a period of one (1) year
from the date of shipment against defects in material or workmanship. Should any evidence of
defects in material or workmanship occur during the warranty period, MSR-Electronic GmbH |
INTEC Controls will repair or replace the product at their own discretion, without charge. This
warranty does not apply to units that have been altered, had attempted repair, or been subject to
abuse, accidental or otherwise. The warranty also does not apply to units in which the sensor
element has been overexposed or gas poisoned. The above warranty is in lieu of all other express
warranties, obligations or liabilities.
This warranty applies only to the PolyGard®2 devices. MSR-Electronic GmbH | INTEC Controls shall
not be liable for any incidental or consequential damages arising out of or related to the use of the
PolyGard®2 devices.
1.6 Part Disposal
Within the EU, in accordance with Directive 2012/19/EU, the device must not be
disposed of as municipal waste. Return the device for disposal to your national sales
organization, which you can contact if you have any questions about disposal.
Outside the EU, you have to consider the corresponding directives.
2 Functional Description
2.1 General
The Sensor includes a µController for measurement value processing in addition to the gas sensor
element and the measuring amplifier. All data and measured values of the sensor element are stored
in a fail-safe way in the µController and are transferred via the digital interface to the sensor board.
The calibration management is also integrated in the µController (microprocessor) of the sensor.
The sensor SC2 is connected to DT6, DC6, SGC6, or SCM6.
The sensor AT6 works according to the same principle as the SC2 series with the exception that the
AT6 outputs an analog signal of 4–20 mA (2–10 V as an option).
2.2 Measuring Mode
See description of the DT6, DC6, SGC6, SCM6 devices
2.3 Special Mode
See description of the DT6, DC6, SGC6, SCM6 devices
INTEC Controls | 12700 Stowe Drive, Suite 100, Poway, CA 92064 | Ph: [phone] & (888) GO.INTEC | inteccontrols.com
Specifications subject to change without notice. | GA_MC2_SC2_E, 2022-05-31 | USA 220907 | Page 6of 28
SC2-AT6 – UserManual

2.4 Sensor Element
A: Catalytic Sensor Element (Pellistor) for Combustible Gases
The integrated sensor works according to the catalytic bead principle. The ambient air to be moni-
tored diffuses through the opening into the sensor. Here the combustible gases and vapours are
burned catalytically at a heated detector (Pellistor). The resulting combustion heat also heats up the
detector. This heating changes the resistance of the detector which is proportional to the concentra-
tion of the combustible gases.
In addition to the catalytic detector, the sensor also has a similarly heated inactive compensator.
Both components are part of a Wheatstone measuring bridge. Environmental influences such as tem-
perature, air humidity or thermal conductivity of the ambient air to be monitored affect both com-
ponents to the same extent so that these influences have no significant effect on the measuring
signal.
The ageing process is accelerated by the high temperatures that occur during the combustion of the
measuring gas. Therefore, a calibration of Zero and Gain must be carried out at regular intervals (see
chapter 6).
For testing the sensor, do not use a lighter. If gassed with a lighter the sensor is unusable for meas-
urement. The warranty expires by gassing with a lighter.
B: Electrochemical Sensor Element for Toxic Gases and Oxygen
The sensor element is a sealed electro-chemical cell with 3 electrodes, sensing, reference and coun-
ter or with 2 electrodes, sensing and reference. The ambient air to be monitored diffuses through a
membrane filter into the sensor element. The chemical process of the measurement is based on a
redox reaction creating a flow of electrons that leads to a DC microampere signal between the sens-
ing and reference electrodes. This signal is linear to the volume concentration of the sensed gas. The
signal is evaluated by the connected amplifier and transformed into a linear output signal.
Electrochemical processes always lead by-and-by to a loss of sensitivity. Therefore, regular calibra-
tion of zero-point and gain is necessary. See chapter 6.
There is a small quantity of corrosive liquid in the sensor element. If in case of damage
persons or objects touch the liquid, you have to clean the affected areas as fast and care-
fully as possible with tap water. Out of use sensors must be
disposed in the same way as
batteries.
INTEC Controls | 12700 Stowe Drive, Suite 100, Poway, CA 92064 | Ph: [phone] & (888) GO.INTEC | inteccontrols.com
Specifications subject to change without notice. | GA_MC2_SC2_E, 2022-05-31 | USA 220907 | Page 7of 28
SC2-AT6 – UserManual

C: Semiconductor Sensor Element for Freon Gases, Ethylene and Ammonia
Semiconductor gas sensors (metal oxide sensors) are electrical conductivity sensors. The resistance
of its sensitive layer changes upon contact with the gas to be detected. The gas then reacts with the
sensor surface. This reaction is reversible in the ideal case. Due to their chemical properties metal
oxide gas sensors are suitable for a wide range of applications and the detection of all reactive gases.
Depending on the materials used and the gases to be detected, common operating temperatures
in the semiconductor sensor are between 300°C (572°F) and 900°C (1652°F). The signal is double
logarithmic to the gas concentration –not linear. The current is evaluated by the subsequent
measuring amplifier and converted into a linear output signal.
Oxidation processes lead by-and-by to an unwanted influence on the alteration of the conductivity.
Therefore, regular calibrations of zero-point (Zero) and gain are necessary (see chapter 6).
Semiconductor sensors are not linear on principle. This means that the sensor would only measure
accurately on the calibrated point and not over the entire measuring range. Therefore, a linearization
is included in our software to improve this behaviour. But since the sensor resistance of a semicon-
ductor elements may be very different, it must be normalized. This can be done via the potentiome-
ter on the PCB. Thus, the different output signals can be changed accordingly and adjusted appropri-
ately.
D: Infrared Sensor Element for Methane, Propane and Carbon Dioxide
The integrated sensor is based on the principle of the infrared absorption of gases and accomplishes
highest requirements concerning accuracy, reliability and economy. The Premium IR Sensor head is
gold-plated inside in addition and therefore offers best performance characteristics in terms of drift,
stability and reproducibility. The sensor technology uses the individual absorption spectrum of the
infrared-active molecule and determines its exact concentration through its accurate, quantitative
analysis. The infrared principle nearly eliminates the cross-sensitivity to other gases.
Due to the measuring principle, these sensors require little maintenance, but MSR | INTEC Controls
recommends regular calibration of the sensors.
For all sensor elements:
Certain substances and gases in the ambient air to be monitored can affect the sensitivity
of the sensor element or destroy the sensor completely. This is called poisoning.
The following are currently known:
•Polymerising substances, such as ethylene oxide, acrylonitrile, butadiene, styrene, silicone
and silicone vapours.
•Corrosive substances, such as halogenated hydrocarbons.
•Catalytic poisons, such as sulphur and phosphor compounds, silicon compounds, metal va-
pours.
•Organic solvents
•Oils and lubricants
INTEC Controls | 12700 Stowe Drive, Suite 100, Poway, CA 92064 | Ph: [phone] & (888) GO.INTEC | inteccontrols.com
Specifications subject to change without notice. | GA_MC2_SC2_E, 2022-05-31 | USA 220907 | Page 8of 28
SC2-AT6 – UserManual

3 Installation
Check the order for completeness and correctness using the delivery papers and unit la-
bels.
Electronics can be destroyed by electrostatic discharge (ESD). Therefore, the installation
work should be done only by persons connected to ground, e. g. by standing on a conduc-
tive floor or by taking appropriate grounding measures (acc. to DIN EN 100015).
3.1 Mounting Instructions
See description of the DT6, DC6, SGC6, SCM6 devices. When
choosing the mounting site please pay attention to the following:
•It is mandatory to comply with the legal requirements for the installation of gas detectors.
•The optimum mounting location may vary depending on the area of application.
•The recommended mounting height depends on the relative gas density of the type of gas
to be monitored.
Depending on the relative gas density (d), the following recommendation applies:
d < 0.90: Mount 0.3–0.5 m (about 1 ft) below the ceiling
0.90 < d < 1.10:
d > 1.10:
Mount at a height of 1.2–1.8 m (5-6 ft) above floor
Mount at a height of 0.3–0.5 m (about 1 ft) above floor
Combustible Gases Chemical Formula LEL (EU) /
% vol
Sensitivity % EU %
(Factor) /Methane
Rel. Gas Density
(Air= 1)
Acetone
(CH3)2CO
2.5
40
2.00
Ammonia
NH3
14
0.60
Petrol Vapours
n.d.
Benzene
C6H6
1.2
35
2.70
Butadiene
C4H6
1.4
50
1.92
Butyl acetate
C6H12O2
1.2
25
4.01
Cyclohexane
C6H12
1.0
50
2.90
Cyclopentane
C
5
H
10
1.4
65
2.42
Ethane
C
2
H
6
2.4
60
1.05
Ethyl acetate
CH
3
COOC
2
H
5
2.0
40
3.04
Ethanol (Ethyl alcohol)
C
2
H
5
OH
3.1
45
1.59
Ethylene
C
2
H
4
2.4
70
0.97
Iso/n-Butane
C4H10
1.4
50
2.08
Iso/n-Pentane
C5H12
1.1
45
2.49
Isobutyl alcohol
C4H10O
1.4
35
2.55
Isopropyl alcohol
(CH3)2CHOH
2.0
35
2.07
LPG
55
n.d.
Methane
CH4
4.4
100
0.56
Methanol
CH3OH
6.0
75
1.10
Methyl acetate
C3H6O2
3.1
50
2.56
Methyl ethyl ketone
CH3COCH2CH3
1.5
40
2.48
n-Heptane
C7H16
0.84
35
3.46
n-Hexane
C6H14
1.0
40
2.97
Nonane
C9H20
0.7
25
4.43
Octane
C8H18
0.8
30
3.94
Propane
C3H8
1.7
55
1.55
Propene
C3H6
1.8
1.48
Toluene
C
6
H
5
CH
3
1.0
30
3.18
Hydrogen
H
2
4.0
110
0.07
Table 1: Combustible Gases
INTEC Controls | 12700 Stowe Drive, Suite 100, Poway, CA 92064 | Ph: [phone] & (888) GO.INTEC | inteccontrols.com
Specifications subject to change without notice. | GA_MC2_SC2_E, 2022-05-31 | USA 220907 | Page 9of 28
SC2-AT6 – UserManual

Toxic Gases Chemical Formula Rel. Gas Density (air= 1)
Ammonia
NH3
0.60
Chlorine
Cl
2
2.48
Hydrogen chloride
HCl
1.27
Hydrogen cyanide
HCN
0.93
Ethylene
C2H4
0.97
Ethylene oxide ETO
C2H4O
1.56
Formaldehyde
CH2O
1.04
Carbon dioxide
CO
2
1.53
Carbon monoxide
CO
0.97
Ozone
O3
1.66
Oxygen
O2
1.11
Sulphur dioxide
SO2
2.73
Hydrogen sulphide
H2S
1.19
Nitrogen dioxide
NO
2
2.80
Hydrogen
H
2
0.07
Table 2: Toxic Gases
Freon Gases Group Product Code Calibration Gas Rel. Gas Density (air= 1)
FR % LFL
S2020
Respective Gas
>1
FR02
S2061
R23
>1
FR03
S2063
R1234yf
>1
FR04
S2064
R123
>1
FR06
S2070
R22
>1
FR07
S2077
R134a
>1
FR08
S2080
R407c
>1
Table 3: Freon Gases
•Choose mounting location of the sensor according to the local regulations.
•Consider ventilation conditions! Do not mount the sensor near the airflow (air passages, suc-
tion holes etc.).
•Mount the sensor at a location with minimum vibration and minimum variation in temperature
(avoid direct sunlight).
•Avoid locations where water, oil etc. may influence proper operation and where mechanical
damage might be possible.
•Provide adequate space around the sensor for maintenance and calibration work.
3.2 Mounting of Sensors
The Sensor is supplied in a separate package and should be installed on the housing only during
commissioning to protect it against dirt and damage.
•Check gas type, range and calibration date of the sensor.
•Define installation place on the housing and break out knockouts.
•Tighten the Sensor with M25 hexagon lock nut.
INTEC Controls | 12700 Stowe Drive, Suite 100, Poway, CA 92064 | Ph: [phone] & (888) GO.INTEC | inteccontrols.com
Specifications subject to change without notice. | GA_MC2_SC2_E,2022-05-31 | USA 220907 | Page 10 of 28
SC2-AT6 – UserManual

4 Electrical Connection
4.1 Plug Connection (SC2) in DT6, DC6, SGC6, SCM6
SC2 sensors are equipped with a reverse polarity protected connector (3-pin). It must not be plugged
in the wrong position by force.
•Plug in the Sensor SC2 at the designated plug-in terminal. Observe plug polarity, the plug must
engage.
The local bus sockets on the sensor boards are connected in parallel, so it is irrelevant to
which socket the SC2 is connected (exception: SGC6, SCM6).
4.2 Terminal Connection (AT6)
•Open cover.
•Insert cable from above, cut and strip it.
•Connect it to the terminal (only 3-wire connection possible).
•For the 4–20 mA mode, please remove the built-in 500 Ω resistor between terminals 2 and 3.
0 VDC
Sensor Unit
AT6-X-XXXX
X2
1
2
3
4
DO 1
DO 2
AT6 Display
Digit al Out put
(Option)
max. 30V / 50mA
1
23
+24 V
4- 20 m A
/ 2-10V
X2
1
2
3
4
DO 1
DO 2
max. 30V / 50mA
ooo
Figure 1: Terminal connections AT6 Figure 2: Terminal connections AT6 with options
4.3 Registration of the Sensors SC2/AT6
Registration (SC2/AT6) and addressing of the field bus address (only SC2): See description of the
DT6, DC6, SGC6, and SCM6.
0 VDC
Sensor Unit
AT6-X-XXXX
1
2
3
+24 V
4-20mA
/ 2-10V
ooo
INTEC Controls | 12700 Stowe Drive, Suite 100, Poway, CA 92064 | Ph: [phone] & (888) GO.INTEC | inteccontrols.com
Specifications subject to change without notice. | GA_MC2_SC2_E,2022-05-31 | USA 220907 | Page 11 of 28
SC2-AT6 – UserManual

5 Commissioning
5.1 General
Only trained technicians should perform the following when commissioning:
•Check for correct mounting location.
•Check for correct connection.
•Install the Sensor(s) if not already installed ex works.
•Check Sensor SC2 connector for correct engagement.
•Check power voltage (AT6).
•Check if connection is correct (AT6).
•Calibrate (if not already factory-calibrated).
Within the first weeks after commissioning, there may be a deviation in the sensor behaviour.
5.2 Required Instruments for commissioning (calibration)
•Service-Tool STL6 or
•DPT6 EasyConfig Software incl. USB/RS-485 communication set
•For AT6, in addition to tool or software, adapter CONKIT-AT6-CalCable
•Calibration:
oZero calibration: Test gas bottle with synthetic air (21 % O2. 79 % N2) or clean ambient
air
oZero calibration for carbon dioxide / oxygen: Test gas cylinder with pure nitrogen 5.0
oGain calibration: Test gas bottle with test gas in the range 30–90 % of the measuring
range. The rest is synthetic air.
oGain calibration for semiconductor sensors: The concentration of the test gas must be
50 % of the measuring range. The rest is synthetic air.
oExtraction set consisting of gas pressure regulator and flow controller
oCalibration adapter with tube: Type CONKIT-PG2.
oCalibration adapter with tube for IR sensors with lateral 2nd gas inlet:
Consult INTEC Controls.
6Calibration
The STL6 Service-Tool or DPT6 EasyConfig Software are available for convenient on-site
calibration. See description of STL6 Service-Tool or DPT6 EasyConfig Software.
There is also the possibility to exchange the sensor against a calibrated one on site. The used sensor
can then be calibrated directly in the office or at INTEC Controls and then reused again.
Please observe proper handling procedures for compressed gas and test gas bottles
(regulations TRGS 220)!
Test gas can be toxic, so never inhale it!
Symptoms: Dizziness, headache and nausea.
Procedure if exposed: Remove victim to fresh air, seek medical attention.
INTEC Controls | 12700 Stowe Drive, Suite 100, Poway, CA 92064 | Ph: [phone] & (888) GO.INTEC | inteccontrols.com
Specifications subject to change without notice. | GA_MC2_SC2_E,2022-05-31 | USA 220907 | Page 12 of 28
SC2-AT6 – UserManual

6.1 Run-in Time
Prior to calibration, the sensors must be supplied with power voltage without interruption
for run-in and stabilisation. The run-
in time depends on the sensor element and is shown
in the following tables.
A: Catalytic Sensor Element (Pellistor)
for Combustible Gases
Run-in time
calibration (h)
Warm-up
time (s)
Flow rate1
(ml/min)
Gas application time
(s)
All Pellistor sensors
24
300
150
120
Table 4: Calibration Pellistor Sensor Element
B: Electrochemical Sensor
Element
for Toxic Gases and Oxygen
Formula
Calibration with
surrogate gas (ratio
surrogate gas : gas)
Run-in time
calibration
(h)
Warm-up
time (s)
Flow rate
(ml/min)
Gas application
time2(s)
Ammonia
NH3
-
24
300
500
180
Chlorine
Cl2
NO21:1 CL2
24
30
500
180
Hydrogen chloride
HCl
H2S 20:31 HCl
24
30
500
120
Hydrogen cyanide
HCN
H2S 15:25 HCN
24
30
500
120
Ethylene
C2H4
24
30
500
180
Ethylene oxide
ETO
-
24
30
500
180
Formaldehyde
CH2O
CO 7:1 CH2O
24
30
500
120
Carbon monoxide
CO
-
24
10
500
120
Ozone
O3
NO21:1 O3
24
30
500
180
Oxygen
O2
-
24
10
500
180
Sulphur dioxide
SO2
-
24
30
500
120
Hydrogen sulphide
H2S
-
24
30
500
120
Nitrogen dioxide
NO2
-
24
60
500
180
Wasserstoff
H2
-
24
30
500
180
Table 5: Calibration Electrochemical Sensor Element
C: Semiconductor
Sensor Element
Stabilisation time until
specification (min)
Run-in time
calibration (h)
Warm-up time
(s)
Flow rate1
(ml/min)
Gas application
time (s)
All Freon gases
60
24
300
150
180
NH3 / C2H4
24
300
150
Max. 90
Table 6: Calibration Semi-Conductor Sensor Element
* A run-in time of 168 h is recommended for initial commissioning.
D: Infrared-
Sensor Element
Run-in time
calibration (h)
Warm-up time
(s)
Flow rate1
(ml/min)
Gas application
time2(s)
Methane, propane, carbon dioxide (Premium sensor)
1
30
150
180
Methane, propane, carbon dioxide
1
30
1500
180
Table 7: Calibration Infrared Sensor Element
1 Stainless steel housing option requires a flow rate of 500 ml/min.
2 Stainless steel housing option requires longer gas application times.
INTEC Controls | 12700 Stowe Drive, Suite 100, Poway, CA 92064 | Ph: [phone] & (888) GO.INTEC | inteccontrols.com
Specifications subject to change without notice. | GA_MC2_SC2_E,2022-05-31 | USA 220907 | Page 13 of 28
SC2-AT6 – UserManual

6.2 Calibration Work
Prior to calibration you have to activate the mode “Special Mode” at the basic device, only then the
calibration menu is enabled. During the special mode, the basic device does not issue alerts.
•Connect calibration adapter carefully to the sensor.
•Connect calibration tool you want to use to the sensor board.
•Open calibration mode in the dialog.
•Select the sensor to be calibrated by selecting the gas type.
•Wait for warm-up time to elapse (see Table 4 to Table 7 Calibration).
6.2.1 Zero Calibration
•Open Zero Calibration dialog.
•The current zero offset and the offset value of the first calibration is read by displaying.
•Apply synthetic air to the sensor head with a flow rate according to Table 4 to Table 7 Calibra-
tion, 1 bar ± 10 %, for 3 minutes (for CO2and O2sensors min. 5 minutes with nitrogen).
•After the application time has elapsed, the new zero-offset factor is calculated by confirming.
The new offset factor is checked for plausibility and stored in the buffer memory. The current
measured value is output with the new offset factor and the offset display is updated.
•With "Save" the new offset factor is written, only then the Zero calibration has been success-
fully completed. If you exit the menu without pressing "Save", the original offset data for the
measured value calculation will continue to be used.
With a reading > 10 % of measuring range during the zero calibration, zero calibration is not possi-
ble.
6.2.2 Gain Calibration
•Open Test Gas dialog and enter test gas concentration (value between 30–90 % of the meas-
uring range, for semiconductor sensors 50 %)
•Open Gain Calibration dialog.
•The current sensor element sensitivity is read by displaying.
•Apply test gas (flow rate and application time according to Table 4 bis Table 7 Calibration,
1 bar ± 10 %) to the sensor head.
•After the application time has elapsed, the new gain factor is calculated by confirming.
The new gain factor is checked for plausibility and stored in the buffer memory. The current
measured value is output with the new gain factor and the sensor element sensibility is up-
dated.
•With "Save" the new gain factor is written in the memory, only then the gain calibration has
been successfully completed. If you exit the menu without pressing "Save", the original gain
data for the measured value calculation will continue to be used.
By limiting the gain factor, calibration will not be possible anymore when the sensitivity of the sensor
reaches a residual sensitivity of 30 %. Then the sensor has to be replaced.
It is required to document the successful calibration with a protocol and to attach a label to the sen-
sor board containing the date for the next calibration.
For more information, see the user manual of the corresponding sensor boards and tools.
INTEC Controls | 12700 Stowe Drive, Suite 100, Poway, CA 92064 | Ph: [phone] & (888) GO.INTEC | inteccontrols.com
Specifications subject to change without notice. | GA_MC2_SC2_E,2022-05-31 | USA 220907 | Page 14 of 28
SC2-AT6 – UserManual

6.2.3 Calibration (Gain) with Surrogate Gas for Catalytic Sensor Element (Pellistor)
For certain gases it is possible to perform a cross calibration with methane (see Table 1: Combustible
Gases). The concentration of the calibration gas is calculated according to the following formula:
Calibration gas = Gas concentration x 100
Factor
6.2.4 Extended Calibration for Semiconductor Sensor Element
If the set test gas has not been reached in the display, an extended calibration must be carried out.
Extended Zero Calibration
•Apply test gas to the sensor (see Table 4 to Table 7 Calibration)
•The processor input voltage must be measured against ground (gas-dependent) at the pin led
out.
•Set the voltage to 1650 mV using the potentiometer.
•Stop and remove gassing and wait until the sensor has stabilized (wait at least 6 hours - stable
zero point).
•Open Zero Calibration dialog.
•Perform zero-point calibration (Display →Calculate →Save)
Gain Calibration:
•Open the test gas dialog and enter the concentration of the test gas used.
•Open the Gain Calibration dialog.
•Apply the test gas (see Table 4 to Table 7 Calibration)
•Perform gain calibration.
•Save the new values after successful gain calibration.
6.3 Calibration Analog Output
When recalibrating an AT6 series sensor, you have to recalibrate the analog output for the new sen-
sor, too. Otherwise, deviation between the digital display and the output current at the AO is to be
expected.
Measure the analog output (AT6) in relation to the calibration value.
(2 % tolerance of the measured value); to 100 0.1 % resistance.
If there is a higher deviation, calibrate the analog output according to the DPT6 EasyConf Software
or STL6 User Manual.
INTEC Controls | 12700 Stowe Drive, Suite 100, Poway, CA 92064 | Ph: [phone] & (888) GO.INTEC | inteccontrols.com
Specifications subject to change without notice. | GA_MC2_SC2_E,2022-05-31 | USA 220907 | Page 15 of 28
SC2-AT6 – UserManual

6.4 Exchange of Sensors
Instead of the on-site calibration, the used sensor can be replaced simply and conveniently by a cal-
ibrated one.
6.4.1 Sensor SC2
The communication of the local bus (SC2 <> Sensor Board) is continuously monitored
during operation and
results in an immediate error message on the gas controller in
case of fault or interruption. When replacing the sensor unit, the communication of the
local bus is interrupted when unplugging the SC2 connector which leads to an immedi-
ate triggering of the error message.
•Disconnect the SC2 connector from the sensor board or the remote board (error message will
be activated).
•Loosen the locknut.
•Remove used SC2.
•Take calibrated SC2 out of the original packaging, check for gas type, measuring range and
valid calibration date.
•Insert the SC2 and retighten with lock nut.
•Insert the SC2 plug into the socket at the sensor board or remote board. Check plug for proper
engagement.
The local bus communication is automatically established and tested. At the same time, the gas type
and the measuring range of the "new" SC2 are compared with the data stored in the sensor board. If
they match and the communication is correct, the error message will be automatically acknowledged
in the sensor board.
The yellow LED of the sensor board is continuously lit as long as the SC2 connector is disconnected
(communication error). After the local bus communication has been re-established and the conform-
ity test has been successful, the board stays in the error stat until the sensor’s warm-up time is over.
6.4.2 Sensor AT6
•Disconnect the used AT6 sensor head.
•Loosen the lock nut. Remove the used AT6 sensor head.
•Take calibrated AT6 sensor head out of the original packaging, check for gas type,
measuring range and valid calibration date.
•Insert AT6 sensor head and tighten with locknut.
•Reconnect the new AT6 sensor head.
6.4.3 Perform Function Test
The sensor is gassed with a defined concentration, the measurement signal at the analog output, the
relay outputs or the digital display is to be checked.
With this test, the complete function chain “Sensor Element > Sensor > Local Bus (SC2) or
Analog Output Signal (AT6) > Sensor Board > Field Bus > Evaluation Unit” is tested.
INTEC Controls | 12700 Stowe Drive, Suite 100, Poway, CA 92064 | Ph: [phone] & (888) GO.INTEC | inteccontrols.com
Specifications subject to change without notice. | GA_MC2_SC2_E,2022-05-31 | USA 220907 | Page 16 of 28
SC2-AT6 – UserManual

7 Inspection and Service
Inspection. service and calibration of the sensor should be done by trained technicians at
regular intervals. We therefore recommend concluding a service contract with INTEC Controls or
one of their authorized partners.
According to EN 45544-4, inspection and service have to be executed at regular intervals. The max-
imum intervals have to be determined and respected by the person responsible for the gas
warning system according to the legal requirements. MSR-E | INTEC Controls recommends
employing the common inspection and service intervals as specified in the general regulations of
the gas measuring technique. We recommend an inspection interval of 3 months. The
recommended calibration intervals depend on the sensor element and can be found in the
Technical Data. If different intervals are valid, always observe the shortest one.
Inspections and services must be documented. The date for the next maintenance has to be affixed
to the sensor.
7.1 Inspection
Gas sensors should be controlled regularly by a competent person according to EN 45544-4. The
following has to be checked in particular:
•Maintenance/calibration interval not exceeded.
•Visual inspection of the sensor including cable for damage, vandalism etc.
•Remove dust deposits, especially at the gas inlet.
•The filter at the gas inlet has to be replaced if extremely dirty.
7.2 Service and Calibration
When performing the maintenance you have to do the calibration and the functional test, see chapter
6, in addition to the inspection.
A fixed calibration interval is stored for each sensor type.
SC2 Sensors:
If this interval is exceeded, a digital maintenance message is generated and forwarded.
Performing the calibration automatically deletes this message.
AT6 Sensors:
If this interval is exceeded, the current output of the AT6 goes to a fixed 19 mA signal. For new
devices (factory calibration), the interval may be exceeded by a factor of 1.5.
After voltage recovery, there is a defined interruption of this message. This can be of use in order to
employ the device without the maintenance message for a few days (adjustable in system parame-
ters -> error time, value range > 0) until the recalibration is performed.
Performing the calibration automatically deletes this message.
Note: With AT62 sensor head software version 1.02.11 and higher (can be read out under
Operating data -> Software version), this function is switched off ex works (System parameters ->
Error time, value range = 0). The AT6 error time can be set with STL6 (from software version
1.02.09) and with DPT6 EasyConfig (from version 1.2.3.5, with CONKIT-AT6-CalCable adapter).
INTEC Controls | 12700 Stowe Drive, Suite 100, Poway, CA 92064 | Ph: [phone] & (888) GO.INTEC | inteccontrols.com
Specifications subject to change without notice. | GA_MC2_SC2_E,2022-05-31 | USA 220907 | Page 17 of 28
SC2-AT6 – UserManual

8 Troubleshooting
8.1 Indications for the SC2
There are no diagnostic indicators on the SC2 sensor modules; they are only available on
the DT6, DC6, SGC6, or SCM6.
8.2 Indications for the AT6
The 4–20 mA output of the AT6 can be used as diagnostic indicators.
Output current
Device error: 2 mA
Tolerable negative sensor drift: 3–4 mA
Normal measurement mode: 4–20 mA
Tolerable overrange: 20–21.2 mA
Overrange error: > 21.8 mA
Maintenance message: 19 mA
9 Specifications
9.1 General
All specifications were collected under optimal test conditions.
We confirm compliance with the minimum requirements of the applicable standard.
REGULATIONS
Directives
(only in connection with sensor
boards from INTEC Controls)
EMC Directives 2014/30/EU
CE
Compliance with: (see corresponding datasheet)
EN 378
EN 14624
EN 45544-1, -3
EN 50104 (for O2)
EN 50271
EN 50545-1
EN 61508-1-3
EN 61010-1:2010
ANSI/UL 61010-1
CAN/CSA-C22.2 No. 61010-1
Warranty
1 year on sensor (not if poisoned or overloaded),
2 years on device
INTEC Controls | 12700 Stowe Drive, Suite 100, Poway, CA 92064 | Ph: [phone] & (888) GO.INTEC | inteccontrols.com
Specifications subject to change without notice. | GA_MC2_SC2_E,2022-05-31 | USA 220907 | Page 18 of 28
SC2-AT6 – UserManual

9.2 Digital Sensor SC2
ELECTRICAL
Power supply
5 V DC from sensor board (e.g. DT6), reverse polarity protected
Power consumption
•Catalytic (Pellistor)
•Electrochemical
•Semiconductor
•Infrared Premium
•Infrared
200 mA, max. (1.0 VA)
10 mA, max. (0.05 VA)
160 mA, max. (0.8 VA)
60 mA, max. (0.3 VA)
50 mA, max. (0.25 VA)
Serial interface local bus
1-wire / 19200 Baud
PHYSICAL
Housing in plastic
Polycarbonate
Combustion
UL 94 V2
Housing colour
RAL 7032 (light grey)
Dimensions: Housing type P
Housing type L
(D x H) 24 x 22 mm (0.94 x 0.87 in.)
(D x H) 24 x 30 mm (0.94 x 1.18 in.)
Weight
Approx. 30 g (0.07 lb)
Protection class
IP65
Mounting
Screw mounting
Connection type
Cable length
3-pin connector
Approx. 150 mm (5.91 in.) standard w/o cable extension
9.3 Analog Sensor AT6
ELECTRICAL
Power supply
18–29 V DC, reverse-polarity protected;
18–27 V AC (only for output signal 2–10 V)
Power consumption
•Catalytic (Pellistor)
•Electrochemical
•Semiconductor
•Infrared Premium
•
Infrared
75 mA, max. (1.8 VA at 24 V)
23 mA, max. (0.6 VA at 24 V)
75 mA, max. (1.8 VA at 24 V)
75 mA, max. (1.8 VA at 24 V)
40 mA, max. (1.0 VA at 24 V)
Analog output signal
Proportional, overload and short-circuit proof,
load 500 Ω for current signal, ≥ 50 kΩ for voltage signal
4–20 mA or 2–10 V = measuring range
3–4 mA or 1.5–2 V = underrange
> 20–21.2 mA or 10–10.6 V = overrange
2 mA or 1 V = fault
> 21.8 mA or 10.9 V = fault High
PHYSICAL
Housing plastic
Polycarbonate; UL 94 V2
Housing colour
RAL 7032 (light grey)
Dimensions: Type P
(D x H) 24 x 22 mm (0.94 x 0.87 in.)
Weight
Approx. 30 g (0.066 lb)
Protection class
IP65 (only if mounted in housing type A, D)
Mounting
Screw mounting / M25
Wire connection
Screw-type terminal 0.25–1.3 mm2,3-pin, 24 to 16 AWG
INTEC Controls | 12700 Stowe Drive, Suite 100, Poway, CA 92064 | Ph: [phone] & (888) GO.INTEC | inteccontrols.com
Specifications subject to change without notice. | GA_MC2_SC2_E,2022-05-31 | USA 220907 | Page 19 of 28
SC2-AT6 – UserManual

9.4 Sensor Element
A: Catalytic Sensor Element (Pellistor) for Combustible Gases
SENSOR ELEMENT
Gas type and measuring range
Combustible gases, see Ordering Information on Datasheet
Sensor element
Pellistor (catalytic bead) sensor
Temperature range
Humidity range
Pressure range
Oxygen concentration
Storage temperature range
Storage time1
Sensor lifetime
-30 °C to +60 °C (-22 °F to 140 °F)
0–95 % RH not condensing
90–110 kPa
21 % (standard) 18 % minimum level
0 °C to +20 °C (32 °F to 68 °F)
Approx. 6 months
5 years / normal ambient conditions
1If stocked for a longer period, we recommend checking the zero point and recalibrating if necessary.
Gas type Ordering No. Measuring range Accuracy Display resolution Repeatability t90 time Zero-
point varia-
tion
Drift in
air
Calibration interval1 Zero Gain
SC2-/
AT6-
% LEL/ ppm
± %
sig.
% LEL /
ppm
< ± %
sig.
≤ sec.
± % LEL
< % signal/
month
Months
CH4
P3400-A
0–100 % LEL
1 (CH4)
0.1
2 (CH4)
15
0.5 (CH4)
0.5 (CH4)
2 (CH4)
6
NH3
P3408-A
0–100 % LEL
1 (CH4)
0.1
2 (CH4)
20
0.5 (CH4)
0.5 (CH4)
2 (CH4)
6
NH3
P3408-B
0–20 % LEL
1 (CH4)
0.1
2 (CH4)
10
0.5 (CH4)
0.5 (CH4)
2 (CH4)
6
H2
P3440-A
0–100 % LEL
1 (CH4)
0.1
1 (CH4)
10
0.5 (CH4)
0.5 (CH4)
2 (CH4)
6
C3H8
P3480-A
0–100 % LEL
1 (CH4)
0.1
2 (CH4)
20
0.5 (CH4)
0.5 (CH4)
2 (CH4)
6
C3H8
P3480-B
0–30 % LEL
2 (C3H8)
0.01
2 (C3H8)
15
0.5 (C3H8)
n.d.
2 (C3H8)
6
C3H8
P3480-C
0–5000 ppm
2 (C3H8)
1 (ppm)
2 (C3H8)
15
0.5 (C3H8)
n.d.
2 (C3H8)
6
C3H6
P3481-B
0–30 % LEL
2 (C3H6)
0.01
5 (C3H6)
15
1.0 (C3H6)
n.d.
2 (C3H6)
6
All oth-
ers
PXXXX-A 0–100 % LEL 1 (CH4) 0.1 2 (CH4) n.d. 0.5 (CH4) 0.5 (CH4) 2 (CH4) 6
1Manufacturer-recommended calibration interval for normal environmental conditions.
B: Electrochemical Sensor Element for Toxic Gases and Oxygen
SENSOR ELEMENT
Gas type
Toxic gases, see Ordering Information on Datasheet
Sensor element
Electrochemical
Pressure range
90–110 kPa or
80–120 kPa (NH3, CO, O2all NO2except for 1130-F)
Storage temperature range1
5 °C to 20 °C (41°F to 68 °F) or
0 °C to 20 °C (32°F to 68 °F) for NH3, CO, NO2, O2
10 °C a 30 °C (50 °F to 86 °F) for H2
Storage time2
Approx. 6 months
1A higher storage temperature can have a negative effect on sensitivity and service life.
2 If stocked for a longer period, we recommend checking the zero point and recalibrating if necessary.
INTEC Controls | 12700 Stowe Drive, Suite 100, Poway, CA 92064 | Ph: [phone] & (888) GO.INTEC | inteccontrols.com
Specifications subject to change without notice. | GA_MC2_SC2_E,2022-05-31 | USA 220907 | Page 20 of 28
SC2-AT6 – UserManual