Organic Pollutant Monitor


The OPSA-150 is a organic pollutant monitor that uses HORIBA's proprietary Rotary Cell Length Modulation, a measuring technique incorporating 25 years of expertise. The unit can be used as an organic pollutant monitor at drainage systems for determining compliance with COD monitoring regulations, for monitoring quality of water measuring levels of organic matter at water supply intakes, and as an organic monitor on process lines (phenol meter).

*Pole mount, outdoor cover, and analysis panel are available as options.



Division: Water Pollution
Manufacturing Company: HORIBA Advanced Techno Co., Ltd.


Sensor that makes full use of Rotary Cell Length Modulation

(JAPAN Patent No. 4627022, KOREA Patent No. 10-0840034, CHINA Patent No. ZL200610110930.8)

  • Zero drift correction is perfomed in every cycle of measurement. This correction can eliminate the effect of any interference on cells.

  • Cell length modulation provides readings from multiple measurements, making available results from various cell lengths. This allows the single device to make measurements on a large range of concentrations from as low as 0 to 0.1 Abs, up to 0 to 5.0 Abs.

* CompactFlash is a registered trademark or trademark of SanDisc Corporation in the United States and other countries.


Easy-to-use Control Panel

Control of the OPSA-150 is operated via the intuitively designed touch panel. An interactive setup screen eliminates any doubts that a user may have while operating the unit. The Converted COD and TURB Display allow readings to be confirmed on site.

Automatic Data Recording up to One Year

Internal data memory provides data strage for one year in case of one measuring value per hour. A CompactFlash® card can be used to allow easy transfer of data to a PC.


HORIBA's Proprietary Wiper System

The cell is cleaned continuously by the wiper to eliminate any interference in the measurement light path. Therefore, errors in readings from dirty cells, or differences in results before and after cleaning are not evident.

Sample Failure Switch Input

The sample error alarm provided as an option on the previous OPSA120 is now a standard feature.

Ten Times Increase in Analysis Sensitivity

The mimimum accuracy of analysis ability has been increased to 0.0001 Abs, a ten-fold increase over the previous OPSA-120 unit. Measurements can be made on concentrations as low as 0 to 0.1 Abs.

Product nameOrganic Pollutant Monitor (UV meter)
Measurement itemUV absorbance, VIS absorbance, COD conversion concentration, TURB (turbidity) conversion concentration
Measurement principleDual optical path, Dual wavelength, rotary cell length modulation method
Measurement wavelengthUltraviolet: 253.7 nm, Visible light: 546.1 nm
Structure of analyzer unitCirculation type
Measurement range
(converted by cell 10mm)
UV absorbance/VIS absorbance
Full scale: 0.1 Abs to 5.0 Abs (setting by 0.1 Abs is possible)
Minimum scale0.0001 Abs (changeable to 0.001 Abs)
RepeatabilityWithin ±2.0% of full scale
(Within ±5.0% of full scale for 2.6 Abs to 5.0 Abs)
LinearityWithin ±2.0% of full scale
(Within ±5.0% of full scale for 2.6 Abs to 5.0 Abs)
StabilityWithin ±2.0%/24 h of full scale
(Within ±4.0%/24 h of full scale for 2.6 Abs to 5.0 Abs)
Response timeT90, within 1 minute (flow rate of approximately 5 L/min)
Cleaning method
(cleaning cycle)
Automatic cleaning by wiper (automatic continuous cleaning)
Display methodLCD display:
320 × 240 monochrome graphics LCD data display with dot backlighting (a touch-panel)
Display content:
UV absorbance, VIS absorbance, UV-VIS absorbance, COD conversion concentration, TURB (turbidity) conversion concentration
Calibration methodSolution calibration using zero solution and span solution (calibration solution in the ampoule)
(one-touch calibration is possible)
Sample water conditionTemperature: 2°C to 40°C (should not be frozen)
Flow rate of sample water: Min. 2 L/min, Max. 20 L/min
* Keep the unit warm (or preserve the heat) to ensure protection against frozen sample water in the cold weather.
Ambient temperature and
Ambient temperature: 0°C to 40°C, Ambient humidity: 85% or below
Analog outputPoint: 3
Type: arbitrary 3 items from UV absorbance, VIS absorbance, UV-VIS
absorbance, COD conversion concentration, and TURB (turbidity) conversion
concentration (selectable)
Specification: 4 mA to 20 mA DC or 0 mA to 16 mA DC, insulated output
(however, non-insulated among each channel)
Maximum load resistance: 600 Ω
Contact outputPoint: 6
Type: arbitrary 4 items from POWER OFF, MAINTENANCE (standard, fixed allocation)
ANALYZER ERROR (selectable)
Content: POWER OFF: when the power OFF occurred.
MAINTENANCE: at in-maintenance mode and calibration mode, and when maintenance switch is ON.
Specification: contact output without voltage, a contact
Contact rating: 125 V AC/0.3 A, 30 V DC/1 A
(however, for load resistance) each output COM-independent
Contact inputPoint: 2
Type: Float switch input, time adjustment input
Specification: contact input without voltage (open collector can be connected), insulated input
ON resistance: Max. 100 Ω, Open voltage: 5.5 V DC, Short circuit current:
Max. 10 mA
CommunicationInterface: RS-232C compliant
Communication speed: 19200 bps
Data memoryMemorize the data of measurement value of the measurement item in the main body.
Memorized data can be transferred to the CF card.
Memory interval: 1 minute or 1 hour
Memory time: on the hour every hour
Data memory time: interval of 1 minute: approximately 10 days
interval of 1 hour: approximately 1 year
* The latest data is memorized.
Light source/detectorLight source: low pressure mercury-vapor lamp, detector: silicon photo diode
Piping sockets 
  • Sample inlet Rp-1/2 female
  • Bypass outlet Rc-1/2 female
  • Overflow outlet (1) Elbow fitting, 13A (nominal)
  • Overflow outlet (2) Elbow fitting, 20A (nominal)
  • Drain outlet Rc-1/2 female
  • Discharge Tube coupling, 50A (nominal)
StructureWeather-proofed for outdoor installation (equivalent to IP54)
Main material of each unitSUS, PVC, PP, CR, SiO2
Power100 V to 230 V AC ±10%, 50/60 Hz
Power consumption100 V to 120 V AC, Max. 45 VA
200 V to 230 V AC, Max. 60 VA
MassControl unit: approximately 5.0 kg
Analyzer unit: approximately 5.6 kg
DimensionControl unit: 240 (W) × 104 (D) × 320 (H) mm
Analyzer unit: 200 (W) × 180 (D) × 403 (H) mm
(Protruding portion are not included.)
Painting colorControl unit: Munsel 5PB 8/1
Conditions for installation 
  • Flat and stable places free from strong vibration or shock
  • Places free from dirt or dust, or where no corrosive gases will be generated.
  • At the atmospheric pressure
  • Places not subject to direct sunlight
  • Places well-ventilated
  • Altitude of 2000 m or below

Request for Information

Do you have any questions or requests? Use this form to contact our specialists. * These fields are mandatory.