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Model N500
with NumaView™ Software

CAPS True NO2-NOX-NO Analyzer



Maintenance schedule ​coming soon...


08977B - MANUAL, USER, 500 CAPS NOX.pdfN500 with NumaView™ Software Manual11234 KB
NVS Remote Manual - 08492.pdfNumaView™ Software Remote User Guide867 KB
SAL000076G - Environmental Instruments Overview.pdfEnvironmental Instruments Overview606 KB
SAL000106C - N500 CAPS NOx.pdfN500 Specification1046 KB



​​​ Ranges
​Min: 0-5 ppb full scale
Max: 0-1,000 ppb full scale​
​ Measurement Units
​ppb, ppm, μg/m3, mg/m3 (user-selectable)​
 Zero Noise
< 0.05 ppb (RMS)
 Span Noise
< 0.2% of reading + 50 ppt (RMS)
 Lower Detectable Limit < 0.1 ppb
 Zero Drift
< 0.2 ppb / 24 hours
 Span Drift
​< 0.5% of reading / 24 hours
 Response Time < 60 seconds to 95%
1% of full scale
 Precision 0.5% of reading above 5 ppb
 Sample Flow Rate
1000 cc/min ±10%
 Power Requirements 100-240VAC (50-60Hz), Typical power 110W
 Included I/O 1 x Ethernet (TCP/IP)
1 x RS232 or RS485 (user-selectable)
2 x front panel USB device ports
 Optional I/O Universal Analog Output Board includes (all user-definable):
4 x Isolated Voltage Outputs (5V, 10V; user-selectable)
3 x Individually Isolated Current Outputs (4-20mA)
​Digital I/O Expansion Board includes:
3 x Isolated Digital Input Controls
5 x Isolated Digital Output Controls (user-definable)
3 x Form C Relay Alarm Outputs (user-definable)
 Operating Temperature Range
0 - 40°C (with US EPA approval)​
 Dimensions (HxWxD) 7” x 17” x 23.5” (178 x 432 x 597 mm)
33 lbs (15kg)
​USA EPA Federal Equivalent Method EQNA-0320-256

​​Specifications subject to change without notice.
All specifications are based on constant conditions.


  • ​Ranges: 0-5 ppb to 0-1 ppm, user-selectable
  • True NO2 – NOx – NO measurements
  • Gas Phase Titration (GPT) for NO conversion and measurement
  • Large, vivid, and durable color graphics display with touch screen interface
  • Ethernet TCP/IP, RS-232/485 serial
  • Front panel USB connections for peripheral devices and firmware upgrades
  • Analog output and Digital I/O expansion (options)
  • Fast response compared to Chemiluminescence
  • Exceptional measurement sensitivity
  • Low power consumption
  • Extended maintenance interval
  • Adaptive signal filtering optimizes response time
  • Temperature & Pressure compensation
  • NumaViewTM and NumaViewTM Remote Operating Software
  • Two-year warranty​


The Model N500 CAPS NOX analyzer uses superior Cavity Attenuated Phase Shift (CAPS) Spectroscopy to measure True NO2, NOX, and NO gases. The instrument combines direct NO2 measurements with highly efficient gas phase titration (GPT) to convert and measure the NO gas component. An automatic baseline reference cycle accounts and compensates for any potential baseline drift due to varying environmental conditions. 

CAPS technology is inherently accurate and sensitive, uses very little power, and requires far less maintenance than Chemiluminescence. The Model N500 raises the bar for NO2, NOX, and NO measurement accuracy, while simultaneously reducing instrument operation and maintenance costs.