Ambient Hydrogen Sulfide Monitor

APSA-370/CU-1 Ambient H2S monitor measures SO2 converted H2S through oxidation catalyst based on Ultra Violet Fluorescence. In order to reduce measurement error by water concentration fluctuatin in ambient, humidifier is set at sample line. It enables long-term stability according to stabilizing catalytic reaction.

  • Monitor H2S with high sensitivity range in ambient air continuously.
  • Set humidifier at sample line to satbilize catalytic reaction.


Measurement component:   Hydrogen sulfide (H2S) in ambient air

Measurement principle: Oxidation catalyst + Ultra Violet Fluorescence

Measurement range: 0-0.1/0.2/0.5/1.0 ppm

Lower detectable limit: 2 ppb

Repeatability: ±3.0% of F.S.

Linearity: ±2.0% of F.S.

Zero drift: ±2% of F.S./day

Span drift: ±5% of F.S./day

Response time (T90): 180 sec. or less (from CU-1converter unit)

Sample gas flow rate: approx. 0.7L/min

Operation gas: None

Indication: Measuring value, alarm

Alarm: APSA-370: Calibration error, Battery error, Flow rate error, Pressure error, Temperature error in catalyzer, etc. CU-1: Temperature error in catalyzer

Inpt/Output: 0-1V/0-10V/4-20mA (2 systems: either (1) momentary value and integrated of (2) moving average value)

Contact input/output RS-232C (option)

Temperature/Humidity: 0-40°C / 85% or less

Power: 100/110/115/120/220/230/240 VAC, 50/60Hz

Power consumption: APSA-370: 150VA  CU-1: 150VA

Dimension: APSA-370: 430(W) x 550(D) x 221(H) mm  CU-1: 430(W) x 550(D) x 221(H) mm

Mass:   APSA-370: approx. 19kg   CU-1: approx. 10kg