The Millennium ST Series of toxic gas detectors utilize electrochemical sensing technology to continuously monitor your site for a wide range of toxic gas types. The Millennium ST Series of sensors are fast, accurate, and requires only periodic calibration and maintenance with a typical sensor life of 3-5 years.

ST Series Sensor	Hydrogen Sulfide H2S (ST1200)	Carbon Monoxide CO (ST1600)	Chlorine Cl2 (ST1500)	Ammonia NH3 (ST1700)
Detection Range	0–20/50/100 ppm	0–500 ppm	0–10 ppm	0–100 ppm
Accuracy/Repeatability	3 % full scale/ 1 % full scale	3 % full scale/ 1 % full scale	±2 ppm or ±15 % of reading, whichever is greater/ 2 % full scale	5 % full scale/ 10 % full scale
Span Drift	< 2 % full scale/mth	< 5 % full scale/yr	< 2 % full scale/mth	< 2 % full scale/mth
Response Time	< 30 s – T90	< 30 s – T90	< 60 s – T80	< 90 s – T90
Operating Temperature	-40 °C to +50 °C (-40 °F to 122 °F)	-20 °C to +50 °C (-4 °F to 122 °F)	-20 °C to +50 °C (-4 °F to 122 °F)	-10 °C to +50 °C (14 °F to 122 °F)
Output	Analog 4–20 mA: Max. loop impedance of 800 ohms at 32 VDC or 150 ohms at 10.5 VDC. Isolated or non-isolated loop supply Relays: 3 Form C contacts rated 5 A at 30 VDC/250 VDC
Humidity Range	0-95% non-condensing
Ingress Protection (IP) Rating	IP64
Enclosure Material	Powder Coated Aluminum 6061 (316 Stainless Steel Optional)
Certifications/Approvals	CSA and NRTL/C certified for hazardous locations. Class I, Division 1 (*Division 2 only), Groups C and D. IEC Rating Ex d IIB T6 NEMA 3R