Field-installation type dissolved oxygen meter (DO meter)

For control and management in wastewater treatment and production processes.

Ideal for the management of aeration tanks at facilities such as wastewater treatment plants and industrial wastewater treatment facilities. Featuring a low-cost membrane cap replacement system and safe inner liquids with KCl (potassium chloride).


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

Low-cost sensor replacement

For sensor replacement, only the membrane cap needs to be replaced, making it more cost-effective compared to replacing the sensor chip.

Safe inner liquid

Utilizing a safe KCl solution as the inner liquids.

Product nameDissolved oxygen converter
Combined sensor5505, 5510 (A bipolar diaphragm type polarography sensor)
Combined probeDO-1100
Dissolved oxygen
0 mg/L to 20 mg/L (Display range: 0 mg/L to 22 mg/L)
Saturation degree0% to 200% (Display range: 0% to 200%)
Temperature0℃ to 50℃ (Display range: -10℃ to 110℃)
Dissolved oxygen
0.01 mg/L
Saturation degree1%
RepeatabilityWithin ±0.5% of the full scale (response for equivalent input)
LinearityWithin ±0.5% of the full scale (response for equivalent input)
TemperatureRepeatability±0.5℃(response for equivalent input)
Linearity±0.5℃(response for equivalent input)
Number of output2 (The negative terminals for transmission outputs are internally connected at the same electric potential)
Output type4 mA to 20 mA DC: input/output isolated type
Load resistanceMaximum: 900Ω
LinearityWithin ±0.08 mA (output only)
RepeatabilityWithin ±0.02 mA (output only)
Output rangeOutput 1Dissolved oxygen concentration: Selection from preset ranges or free range input within measuring range.
Output 2Free setting within a range between -20℃ and 130℃
Occasional out for errorHold or burnout to either 3.8 mA or 21 mA
Transmission holdIn the maintenance mode, transmission signal is held at the latest value or preset value.
In the calibration mode, transmission signal can be alive or held.
Contact outputNumber of output3
Output typeNo-voltage contact output
Contact typeRelay contact; SPDT (1c)
Output capacity250 V AC 3 A, 30 V DC 3 A (resistance load)
R1 and R2Selectable from upper limit alarm, lower limit alarm, ON/OFF control, currently holding of transmission output, and cleaning output (The contact is closed during alarm operation, opened normally and while the power is down).
FAILError alarm (Closed in the normal state, opened in the failure state or while the power is down.)
Alarm setting rangeSelectable from dissolved oxygen concentration, and temperature
  • Setting range: Within the measurement range
  • Delay time: 0 to 600 seconds
Control setting range
  • Setting range: 0 mg/L to 20 mg/L
  • Control width: 0.02 mg/L to 200 mg/L(±0.01 to ±0.50 mg/L)
Number of output points1
Output typeContact output with voltage (output of connected power supply voltage)
Contact typeRelay contact; SPST (1a)
Output contact capacity250 V AC 0.5 A
External instrumentSolenoid valve for cleaning control
SettingsCleaning period0.1 hours to 168.0 hours
Cleaning time2 seconds to 600 seconds
Hold time2 seconds to 600 seconds
Timer accuracyWithin 2 minutes per month
Description of cleaning
One of the following operations.
  • Operation of internal timer only
  • Operation of internal timer and external input command
  • Enable the internal timer only when external input is active.
  • The cleaning trigger signal (The external trigger signal must be longer than 2 seconds)
Contact inputNumber of input1
Contact typeNo-voltage “a” contact of open collector
ConditionsON resistance: 100 Ω max.
Open voltage: 24 V DC
Short-circuit current: 12 mA DC max.
Contact functionExternal input for cleaning or transmission holding if cleaner is not attached.
Communication typeRS-485
Signal type2 wire system, isolated from the input circuit
Not isolated from transmission circuit
Applicable temperature
Platinum resistor: 1 kΩ (0℃)
(The temperature sensor is built into the probe DO-1000.)
Temperature compensation
0℃ to 50℃
Temperature calibration1 point calibration comparing to reference thermometer
CalibrationCalibration methodSpan calibration in the air or DO saturated aquaous solution
Number of calibration pointsAtmospheric calibration: 1 point
(Zero electric calibration is carried out automatically)
Saturation liquid calibration : 2 points (zero calibration is omitted)
Additional capabilitiesSalinity compensation (0.0% to 5.0%)
Automatic detection of calibration failure (Zero error, Sensitivity error)
Calibration history (Elapsed days from the last calibration which ever zero or span, zero shift, span sensitivity)
Self-checkCalibration errorZero calibration error, sensitivity error, outside of temperature calibration range
Electrode diagnostic errorSensor error (damage to diaphragm), disconnection of sensor (or damage to sealing), temperature sensor short-circuit, and electric discontinuity of temperature sensor
meter errorCPU error, CPU error, ADC error, memory error
Operating temperature range-20℃ to 55℃ (without freeze)
Operating humidity rangeRelative humidity: 5% to 90% (without condensation)
Storage temperature-25℃ to 65℃
Power supplyRated power supply voltage100 V to 240 V AC ±10% 50/60 Hz
Power consumption15 VA (max)
OthersWith power switch for maintenance use
CE markingEMC  :EN61326-1
      Class A, Industrial electromagnetic environment
Safety  :EN61010-1
RoHS :EN50581
      9. Industrial monitoring and control instruments
FCC rulesPart15 Class A
StructureInstallationOutdoor installation type
Installation methodMounted on 50A pole or wall
Protection codeIP65IEC60529, JIS C0920
Case materialAluminum alloy (coated with epoxy-denatured melamine resin)
Material of fittingsSUS304
Material of hoodSUS304 stainless steel (coated with epoxy-denatured melamine resin)
Material of windowPolycarbonate
Display elementReflective monochrome LCD
External dimensions 180 (W) × 155 (H) × 115 (D) mm (excluding mounting brackets)
Mass Main body: Approx. 3.5 kg; cover and mounting brackets: Approx. 1 kg

*1:   The standard for effect on the reading by the electromagnetic field of the radiated radio frequency and by the conducted interference is within the measured dissolved oxygen value ±0.4 mg/L.

*2:   When the sensor cable, the transmission cable, or the contact input cable is extended to 30 m or longer, the surge test specified in the EMC directive for CE marking is not applied.


An arrester (spark over voltage: 400 V) is implemented for transmission output, contact input, and communication. However, use a most suitable surge absorption element on the connection lines in accordance with the ambient environment, the situation of equipment installed, and the externally connected equipment.

Solicitud de Información

Tiene alguna pregunta o solicitud? Utilice este formulario para ponerse en contacto con nuestros especialistas. * Estos campos son obligatorios.