HT INDUSTRIAL AUTOMATION LIMITED

 
YOKOGAWA DO402G 4-Wire Dissolved Oxygen Analyzer

YOKOGAWA DO402G 4-Wire Dissolved Oxygen Analyzer

Flexibility, reliability and low maintenance are among the benefits provided by the EXA DO402G dissolved oxygen analyzer. Designed to meet the exacting requirements of measuring dissolved oxygen in the modern industrial environment, it contains many features to ensure the best precision whatever the application.

The DO402G features PI control on both the auxilliary mA output and the pulse proportional relay outputs, thus avoiding the need for a separate controller.

The DO402G accepts inputs from both galvanic and polarographic sensors. Percent saturation, mg oxygen/l water, and ppm DO can be displayed and transmitted. Compensation for atmospheric pressure altitude, salinity and temperature are included for the best accuracy of measurement.

 Bulletin for DO402G/DO70G/DO30G 

 General Specification for DO402G 

 General Specification for DO Sensor 

 User's Manual for DO402G 

Featuers

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Free measuring range of 0 to 50 mg/l. Minimum span of 1 mg/l that can be arbitrarily set.

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Either mg/l, ppm, or % saturation can be selected as the unit for display.

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Built-in barometric pressure and salinity compensation functions for high accuracy measurement.

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Small-sized intelligent converter with a built-in wash timer function.

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One-touch calibration using air or a solution saturated with air.

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Provision of various self-diagnostic functions as in the DO sensor (Temperature measured value, membrane failure etc.).

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Incorporation of abundant contact output functions.

Specifications

Input specifications

Input range varies from 0.0 nA up to 500 nA for polarographic sensors and 0.0 to 50 μA for galvanic sensors. Temperature measurement for automatic temperature compensation utilizes Pt100, Pt1000. 22k NTC or PB36 as used in DO8X and DO30 sensors

Input ranges

Dissolved Oxygen: 0 to 50 mg/l (ppm)
Temperature: 0 to 50

Span

DO concentration: minimum: 1 mg/l (ppm), maximum: 50 mg/l (ppm)
% saturation: minimum: 10 %, maximum: 300 %
Temperature: minimum: 25
, maximum: 50

Transmission signals

Two isolated outputs of 0 to 20/4 to20 mA DC with common negative.
Maximum load 600 Ω.

Temperature compensation

0 to 50

Calibration

Semi-automatic calibration with automatic compensation for influence of barometric pressure and altitude on partial pressure of Oxygen in air (or solubility of Oxygen in water). Automatic compensation for influence of salinity of water on solubility of Oxygen in water is programmable.
The correction for pressure, salinity and temperature meets ISO 5814.

Contact outputs

General: Four (4) SPDT relay contacts with LED indicators.
Switch capacity: Maximum values 100 VA, 250 V AC, 5 A
                       Maximum values 50 W, 250 V DC, 5 A
Status: High/low process alarms, selected from process parameter and temperature.
Contact output is also available to signal "Hold active"

Serial communication

Bi-directional according to the EIA-485 standard using HART®-protocol

Contact input

Remote wash cycle start.

Power supply

230 V AC ±15 %, 50/60 Hz, maximum consumption 10 VA
115 V AC ±15 %, 50/60 Hz, maximum consumption 10 VA
100 V AC ±15 %, 50/60 Hz, maximum consumption 10 VA

Performance

DO at process temperature 25 deg C

Linearity

±0.03 mg or ±0.5 % FS, whichever is greater

Repeatability

±0.03 mg or ±0.5 % FS, whichever is greater

Accuracy

±0.05 mg or ±0.5 % FS, whichever is greater

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