Mapa Web Contacte Català | Español

Automatic analyser for NO, model 9841


Operation theory: The Nitrogen Oxydes 9841 is an analyzer by quimiluminiscence that offers measure reliable data of NO, NO2 and NOx.

The 9841 analyzer is a symple channel analyzer, that symplifies its working and offers the maximum fiability. The light that comes from the quimiluminiscence reaction between the ozone and the NO is measured in a single chamber and with a single photomultiplier tube (PMT). The sample to be measured is alternatively conmuted to make it pass or not by a converter (heated molibdene) of NO2 to NO. So, the instrument measures alternatively NO and NOx (NO and NO2 = NOx). The difference between this two lectures enables the calculation of the NO2 value.

The 9841 equipment is equipped with a system to manage the sample disegned to have the analysis of the sample of NO and NOx on the same part of the sample avoiding  the biased lectures caused by the artefact effect due to the conmutation of the sample flow.

That eliminates the requirement of introducing correction factors by mathematical formula, that are mandatory in other equipments.

The final concentration of NO and NO2, corrected to changes of temperature and preassure, are shown on the screen in parts per million (ppm) or miligrams per cubic meter (mg/m3).

The equipment has a graphic display to show the averages, states and historical information in digital format. Through the menus the user can configure the equipment and have acces to all the available options, The 9841 analyzer selects automatically the optimal range of measure both in the screen and in the RS-232 interface output. The values are indicated in the floating point mode, which makes unnecessary the selection and indication of the range of measure. The equipment includes a characteristic of analogical over range that, in activated mode, commutes the analogical output of the analyzer to a ranger higher than the previously defined.

Characteristics and functions

  • European manufacturer ISO9001 certified to ensure the supply of analyzers of quality and exceptional performance
  • The analyzers are approved and certified by the US-EPA and have been contrasted with reference standards by US, UK and TÜV and operate between +5ºC and +40ºC
  • The NO/NO2/NOx analyzer offers equivalent results as the obtained by reference methods commons in USA and CE (USA equivalent method as defined in 40 CFR Part 53)
  • The 9841 analyzer uses a Perma Pure dryer free of maintenance that allows the equipment to work correctly even in conditions of high humidity without having to change the dryer reactives. Due to the fact that the 9841 equipment does not use a mechanical modulator, there is no need to change the belts or motor, which simplifies the maintenance labours
  • The equipment includes a self-diagnosis system and a full remote control through a RS-232 multipoint interface in order to optimize the service and maintenance availability
  • The analyzer has a wide LCD screen to watch simultaneously measure data and information regarding the working parameters
  • The analyzers from the 98xx series are noted for its modular design and for an internal performance at 12 Vcc with a consumption of less of 100 W
  • The equipment has an internal register for relevant events as zero and calibration or specific error indicators up to 20 events
  • It incorporates internal memory in the main board. The data stored can be obtained in a remote mode
  • The low flow of 0,6 l/min reduces the impact of the pollution of the fungibles and reduces the substitution costs and maintenance times
  • Kalman digital filter to give more exactitude and better response to real variations of the atmospheric pollutants concentrations compared with the filters of fixed wide beam of linear type


  • Approval  Number : US-EPA: RFNA-1292-090 TÜV: UBA-21
  • Range:
    • Digital and screen output: Self-range from 0 to 20 ppm. Resolution = 0,001 ppm
    • Analog output: 0 – full scale between 0-0,05 ppm and 0-20 ppm with 0, 5 and 10 % offset
    • Auto ranging analog output: two ranges selectable by the user: 0 – full scale
    • Range designed by USEPA: any range between 0-0,05 ppm and 0-1 ppm.
  • Noise:
    • Measure process: 0,25 ppb or 0,1% of the reading, whichever is greater (with Kalman algorithm active)
    • Analog interface: 0,025 ppm or 0,1 % of the analog full scale, whichever is greater 
  • Lower Detectable Limit:
    • Analog interfase:<0,05 ppm or 0,2% of the analog full scale, whichever the greater 
  • Zero Drift:
    • Temperature dependent:<0,5 ppb/ ºC
    • Time dependent, at fixed temperature:
      • <1 ppb / 24 h
      • <1 ppb / 30 days
  • Span Drift:
    • Temperature dependent:<0,1 %/ ºC 
      • <0,5 %/24 hours of the concentration reading
      • <0,5 %/30 days of the concentration reading
  • Lag Time:<25 s 
  • Rise/Fall Time T95: < 30 sec (with Kalman algorithm active)
  • Error lineality: ±1% of the full scale
  • Precision: 0,5 ppb or 1 % of the concentration reading, whichever the greater
  • Sample Flow Rate: 0,6 l/min approx
  • Temperature Range:
    • TÜV: +5°C to +40°C (41°F to 104°F) -USEPA: +15°C to +35°C (59°F to 95°F)
  • Power Supply:
    • 99 to 132 VCA, 198 to 264 VCA, 47 to 63 Hz
  • Weight: 26,4 Kg 
  • Dimensions (w x h x d): 43,2 cm x 17,8 cm x 64,8 cm
  • Analog Output:
    • Menu selectable current output of 0 to 20 mA, 2 to 20 mA, or 4 to 20 mA
    • Optional vltage output with 50-pin connector board. Jumper selectable voltage output of 100 mV, 1 V, 5 V, and 10 V, with menu selectable zero offset of 0%, 5%, or 10%
  • Digital Output:
    • Multidrop RS232 port shared between analyzers for store of data, status and control

© MCV, SA Legal advice · Privacy Policy · Cookies Policy