1. Nanotechnology Metal Oxide Semiconductor (NTMOS) H2S Gas Sensor
January 2009

2. New Toxic Gas Detector Functional Flexible Reliable
Provides H2S gas detection in extreme temperature and humidity conditions
Detects H2S faster and more accurately than traditional Metal Oxide Sensors (MOS)
Flexible
Can be installed as a stand-alone sensor or combined with a display for local indication
Reliable
Lasts longer and stays awake more than previous MOS H2S gas sensors
Provides accurate and long-lasting operation in extreme climates, as proven through third-party performance testing to the ISA standard

3. Engineered and Designed for H2S Detection
Linear 4-20 mA Output Proportional to ppm H2S
Explosion-Proof, Stainless Steel Housing Approved for Class 1 Division 1 Hazardous Areas
Onboard Humidity Sensor Provides an Accurate Reading in Extreme Climates
Automatic Calibration Line Provides Easy One-person Calibration
Automatic Fault Diagnostics Indication via Current Output
NTMOS Technology Means Higher Sensitivity and Long- lasting Detection
Integrated Temperature Sensor for Compensation

4. Certified to ANSI/ISA Performance Standard
Performance Requirements for Toxic Gas- Detection Instruments: Hydrogen Sulfide
ISA– : New World Standard for Toxic Gas Detection
2.1 This Standard addresses the details of construction, performance, and testing of portable, mobile, and stationary electrical gas-detection instruments operating at ambient temperatures and pressures used to provide a warning of the presence of toxic gases in air. Instruments used to detect flammable (explosive) concentrations of toxic gas(es) when the LEL exceeds the TLV are excluded.

5. New World Standard for Toxic Gas Detection
Specification
Full Scale Range
10 to 100 ppm H2S
0 to 100 ppm H2S *
Temperature Range
14 to 122 °F (–10 to 50 °C)
-40 to 149 °F (–40 to 65 °C) *
Relative Humidity Range
15 to 90%
15 to 90% *
Response Time (Full Scale)
T20 < 10 seconds T50 < 30 seconds
T20  2 seconds * T50  3 seconds *
Accuracy / Linearity
10% of applied gas concentration or 2 ppm
10% of applied gas concentration or 2 ppm *
* In accordance with FMID

6. Designed for Toxic Gas Applications
Designed to be installed where low levels of H2S can be detected to avoid the threat to human beings:
Crude Oil Tank Storage Tank farms storing crude oil and H2S require continuous monitoring for gas leaks. In addition to the tanks, common leak sources include pipes and valves, which require sensors.
Remote Oil / Gas Well Sites Oil and gas well production sites require H2S protection in and around the site. Common monitoring locations include the well heads, flare stacks, and storage tanks.
Oil / Gas Drilling Sites Leaks, such as blowouts in oil drilling applications, are subject to releasing large quantities of H2S gas into areas around the site. Typical gas monitoring locations include the driller stand, bell nipple, shale shaker, and mud tank.

7. Superior H2S Gas Detection
Typical
While conventional electrochemical (E-Chem) gas sensors are typically used to detect H2S Gas…
…our NTMOS sensors detect H2S faster, are more accurate, and last longer in extreme temperature and humidity applications.

8. Environmental Effects on Sensor Performance
Temperature
E-Chem
NTMOS
Low
Med
High
NTMOS
NTMOS
NTMOS
High
E-Chem
E-Chem
E-Chem
No Effect
Affects Performance
Affects Performance and Sensor Life
NTMOS
NTMOS
NTMOS
Humidity
Med
E-Chem
E-Chem
E-Chem
NTMOS
NTMOS
NTMOS
Low
E-Chem
E-Chem
E-Chem

9. Comparing Technologies
Accuracy
Stability
Longevity
Det-Tronics NTMOS Sensor
Metal Oxide Sensor (MOS)
Conventional Electrochemical
Accuracy in High Temperatures No
Yes
Longevity in Extreme Climates
Accuracy in Humid Air
Accuracy in Dry Air
Stable Calibration Over Time

10. How Does the NTMOS Sensor Work?
Target gas reacts with the metal oxide and changes the resistance proportional to the gas concentration.
The large sensor surface area absorbs the gas vapor, thus lowering the potential barrier and sensor resistance.
Because this resistance change is non-linear and specific to each sensor, it is logarithmically correlated to the gas concentration.
Sensor is Incorporated With the Microheater

11. Nanotechnology MOS = More Surface Area
NanoFact
Advantages:
Increased surface area means a faster response and higher sensitivity — typically T50 is less than 5 seconds
Pure material design avoids syndrome of sensor falling asleep
NTMOS tolerates extreme temperature and humidity ranges
Rugged and long lasting sensor technology
Nanotechnology, which deals with devices typically less than 100 nanometers in size, is making a significant contribution to the fields of computer storage, semiconductors, biotechnology, manufacturing and energy.
The additional surface area (~10X) is what gives the NTMOS its advantage over original MOS sensor technology.

12. Ordering the NTMOS

13. Compatible with FlexVu Display
Local Display with Relay, Alarm, and Fault Outputs Combined with isolated 4-20mA
4-20 mA output with HART
Nonintrusive Calibration
Fully Explosion-Proof Housing
Available in 316SS Construction
Easy-to-Set Alarm Levels
Access to Alarm and Fault History
Multiple Conduit Access Points
Det-Tronics NTMOS Shown with FlexVu Display

14. New Toxic Gas Detector Customer Benefits
Fast Response (T50 < 5 sec) Means Increased Safety
Protection in Extreme Climates with Advanced Sensor Humidity and Temperature Compensation
Automatic Calibration with Nonvolatile Memory to Revert to Previous Calibration if Necessary
No Undisclosed Failures due to Internal Diagnostics and Automatic Notification
Reduced Maintenance Costs with quick set-up and easy device interrogation
Det-Tronics NTMOS Shown with FlexVu Display

15. Our Mission Corporate Headquarters, Minneapolis, MN
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