SM-4 Modular Mercury Stack Gas Monitor

SKU: SM-4 Mobile

Technically identical to the SM-4, this device is ideal for mercury determination at varying sites.

The SM-4 Mobile by Mercury Instruments has been developed on the basis of the well proven SM-4 mercury stack gas monitor. Its measurement principle and technique, its thermocatalytic reactor, the detector and the sample probe are identical with those of the stationary SM-4.


  • Brand


Envea Emission


  • Easy to transport
  • Qickly dismounted and reassembled
  • Sample dilution directly at the probe: eliminates interference with virtually any sample matrix
  • Maintenance free low temperature converter directly at stack: no transport of ionic mercury thus minimizing mercury adsorption
  • Detects total mercury (elemental, ionic and bound mercury)
  • Automatic calibration for elementary and ionic Hg
  • Automatic quality control (QAL3) during operation
  • Extremely wide range of measurement:
    0,05 bis 1000 µg/m³


  • Coal fired power plants
  • Waste incineration plants
  • Sewage sludge incineration plants
  • Cement kilns
  • Recording of Hg emission situations as well as determination of the efficency of  mercury reduction systems
  • Method 30A applications
  • Testing of stationary CEMs
  • Optimization of mercury control technologies


Measuring principle thermocatalytic reduction at stack, Amalgamation (MI GoldTrap), cold vapor atomic absorption (CVAAS) at 253.7 nm
Measured component Total mercury (ionic and elemental spe
UV-Source Electrodeless low pressure mercury lamp (EDL)
Stabilization method Reference beam method
Optical cell Fused silica (Suprasil), l: approx. 230mm, heated approx. 45°
Measuring ranges 0,05 μg/m³ to 500 μg/m³ Hg
Detection limit 0,0001 μg/m³ (Detector); < 0,01 μg/m³ (System)
Response time T90 Typically 180 sec
Calibration automatic, with built in calibration gas generator for elementary Hg (option)
automatic, with built in calibration gas generator for ionic Hg (option)
manual, with built in heated fitting for feed of externally provided calibration gas (e.g. HOVACAL®)


Signal outputs analogue: 4-20 mA (500 Ω max.)
serial: RS232
Modbus RTU/RS485 (option)
Ethernet (option)
Status output 3 x pairs of relay contacts (dry contacts)
Remote access Modem and SM-4 software (option)
Max. sample temperature 250 °C
Ambient temperature range allowed -5 to 40 °C
Sample line length up to 90m
Power supply 230 VAC / 50 Hz (110 VAC / 60 Hz option)
El. Power consumption Analyzer cabinet: 450 VA
Air condtioning cabinet: 1000 VA
Heated sample line: 30 VA per meter
Dimensions (H x W x D) Analyzer cabinet: 60 x 60 x 60 cm
Air conditioning cabinet: 73 x 60 x 60 cm
Probe: 75 x 38 x 34 cm
Probe controller: 48 x 44 x 27 cm
Weight Analyzer cabinet: 50 kg
Air conditioning cabinet: 50kg
Probe converter unit: 28kg;
Probe controller: 14 kg
Air consumption peak 35l/min, 6 bar (87 PSI)


The continuous mercury analyzer SM-4 allows the compliance with future measurement obligations (Minamata convention & the European directives for thermal power plants and incinerators).

  • Compliance with US EPA 40CFR60 PS-12A Mercury CEMS;
  • Our products are manufactured according to the ISO 9001 quality regulations.
  • CE approved
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