YOKOGAWA DO402G User's Manual

User’s
Manual

Model DO402G [Style: S3]

Dissolved Oxygen Converter

IM 12J05D02-01E

IM 12J05D02-01E

6th Edition

PREFACE

IM12J05D02-01E065.pdf

TABLE OF CONTENTS

1. Introduction And General Description

............................................................. 1-1

1-1. Instrument Check ............................................................................................ 1-1

1-2. Application ......................................................................................................1-2

1-3. General information ........................................................................................1-3

1-4. Configuration checklist for DO402G ...............................................................1-5

1-5. System Configuration .....................................................................................1-6

1-5-1. Dissolved Oxygen Sensor ...............................................................................................1-6

1-5-2. The holders ......................................................................................................................1-6

2. DO402G SPECIFICATIONS ................................................................................2-1

2-1. General ...........................................................................................................2-1

2-2. Operating specifications .................................................................................2-2

2-3. Model and suffix codes ...................................................................................2-3

3. Installation And Wiring.......................................................................................3-1

3-1. Installation and dimensions

3-1-1. Installation site .................................................................................................................3-1

3-1-2. Mounting methods ...........................................................................................................3-1

............................................................................3-1

3-2. Preparation ..................................................................................................... 3-4

3-3. Wiring the power supply .................................................................................3-5

3-3-1. General precautions ........................................................................................................3-5

3-3-2. Access to terminal and cable entry .................................................................................3-5

3-3-3. AC power .........................................................................................................................3-6

3-3-4. Grounding the housing ....................................................................................................3-6

3-3-5. Switching on the instrument ............................................................................................3-6

3-4. Wiring the contact signals ............................................................................... 3-7

3-4-1. General precautions ........................................................................................................3-7

3-4-2. Contact outputs................................................................................................................3-7

3-4-3. Contact input ..................................................................................................................3-7

3-5. Wiring the analog output signals ..................................................................... 3-8

3-5-1. General precautions ........................................................................................................3-8

3-5-2. Analog output signals ......................................................................................................3-8

3-6. Wiring the standard galvanic sensor .............................................................. 3-8

3-7. Wiring other galvanic sensors ......................................................................... 3-8

3-8. Wiring polarographic sensors ......................................................................... 3-8

3-9. Wiring RS485 signal ....................................................................................... 3-8

4. Operation; Display Functions And Setting

4-1. Operator interface ........................................................................................... 4-1

4-2. Explanation of operating keys ......................................................................... 4-2

4-3. Setting passcodes ..........................................................................................4-3

4-4. Display functions (default) ..............................................................................4-4

5. Parameter setting

5-1. Maintenance mode ......................................................................................... 5-1

5-2. Commissioning mode ..................................................................................... 5-5

IM 12J05D02-01E
6th Edition: Oct. 2007(YK)
All Rights Reserved, Copyright © 2003, Yokogawa Electric Corporation

...................................................... 4-1

............................................................................................... 5-1

5-1-1. Manual activation of Hold ................................................................................................5-2

5-1-2. Manual Wash start/stop ...................................................................................................5-3

5-1-3. Setpoint adjustment .........................................................................................................5-4

5-2-1. Setpoints ..........................................................................................................................5-6

IM 12J05D02-01E

5-2-2. Range ..............................................................................................................................5-8

5-2-3. Hold ..............................................................................................................................5-10

5-2-4. Wash .............................................................................................................................5-12

5-2-5. Service ...........................................................................................................................5-13

5-3. Notes for guidance in the use of service coded settings ..............................5-14

5-3-1. Parameter specific functions .........................................................................................5-14

5-3-2. Temperature functions ...................................................................................................5-16

5-3-3. Calibration functions ......................................................................................................5-16

5-3-4. mA output settings .........................................................................................................5-18

5-3-5. Contact outputs..............................................................................................................5-20

5-3-6. User interface ................................................................................................................5-24

5-3-7. Communication setup ....................................................................................................5-26

5-3-8. General .........................................................................................................................5-26

5-3-9. Test and setup mode ....................................................................................................5-26

6. CALIBRATION PROCEDURE ............................................................................. 6-1

6-1. General ...........................................................................................................6-1

6-1-1. Calibration methods .........................................................................................................6-1

6-1-2. Diagnostic functions performed during calibration ..........................................................6-2

6-2. Calibration procedure using air calibration method ........................................6-2

6-2-1. Preparation ......................................................................................................................6-2

6-2-2. Procedure for air calibration ............................................................................................6-3

6-3. Calibration procedure using water calibration method .................................... 6-4

6-3-1. Preparation ......................................................................................................................6-4

6-3-2. Calibration operation (water calibration method) .............................................................6-4

6-3-3. Procedure for Water calibration .......................................................................................6-5

6-4. Calibration method using manual calibration method ..................................... 6-6

6-4-1. Preparation ......................................................................................................................6-6

6-4-2. Procedure for manual calibration.....................................................................................6-7

7. Maintenance ........................................................................................................ 7-1

7-1. Overall dissolvedoxygen metering system .....................................................7-1

7-1-1. Inspection and maintenance to be implemented periodically ..........................................7-1

7-1-2. Inspection and maintenance to be implemented on occasion ........................................7-1

7-2. Periodic maintenance for the EXA DO402G converter ................................... 7-2

7-3. Fuse Replacement .......................................................................................... 7-2

8. Troubleshooting

.................................................................................................8-1

8-1. Measures in the case of converter operation failure ....................................... 8-1

8-1-1. No dissolved-oxygen converter operation .......................................................................8-1

8-1-2. Operation key or display failure .......................................................................................8-1

8-2. Measures in the case of failure (Error) detection ............................................ 8-2

9. Spare Parts.......................................................................................................... 9-1

10. Appendix

........................................................................................................ 10-1

10-1. Setpoint ....................................................................................................... 10-1

10-2. Range ......................................................................................................... 10-1

10-3. Hold ............................................................................................................10-1

10-4. Wash ........................................................................................................... 10-1

10-5. User setting table ........................................................................................ 10-2

ERROR CODES .................................................................................................. 10-4

11. Appendix 2 Quality Inspection

.......................................................................11-1

Customer Maintenance Parts List (for Style: S3)
Revision Record

IM 12J05D02-01E

..........................................................................................................i

.................. CMPL 12J05D02-03E

PREFACE

CAUTION

WARNINGWARNING

DANGERDANGER

Electric discharge

The EXA analyzer contains devices that can be damaged by electrostatic discharge. When servicing
this equipment, please observe proper procedures to prevent such damage. Replacement components
should be shipped in conductive packaging. Repair work should be done at grounded workstations using
grounded soldering irons and wrist straps to avoid electrostatic discharge.

Installation and wiring

The EXA analyzer should only be used with equipment that meets the relevant IEC, American or
Canadian standards. Yokogawa accepts no responsibility for the misuse of this unit.

The Instrument is packed carefully with shock absorbing materials, nevertheless, the instrument may be
damaged or broken if subjected to strong shock, such as if the instrument is dropped. Handle with care.

Although the instrument has a weatherproof construction, the transmitter can be harmed if it becomes
submerged in water or becomes excessively wet.

Do not use an abrasive or solvent in cleaning the instrument.

Notice

• This manual should be passed on to the end user.

• The contents of this manual are subject to change without prior notice.

• The contents of this manual shall not be reproduced or copied, in part or in whole, without permission.

• This manual explains the functions contained in this product, but does not warrant that they are suitable
the particular purpose of the user.

• Every effort has been made to ensure accuracy in the preparation of this manual.

However, when you realize mistaken expressions or omissions, please contact the nearest Yokogawa

Electric representative or sales office.

• This manual does not cover the special specifications. This manual may be left unchanged on any
change of specification, construction or parts when the change does not affect the functions or
performance of the product.

• If the product is not used in a manner specified in this manual, the safety of this product may be
impaired.

Yokogawa is not responsible for damage to the instrument, poor performance of the instrument or losses
resulting from such, if the problems are caused by:

• Improper operation by the user.

• Use of the instrument in improper applications

• Use of the instrument in an improper environment or improper utility program

• Repair or modification of the related instrument by an engineer not authorized by Yokogawa.

Safety and Modification Precautions

• Follow the safety precautions in this manual when using the product to ensure protection and safety of
the human body, the product and the system containing the product.

The following safety symbols are used on the product as well as in this manual.

This symbol indicates that an operator must follow the instructions laid out in this manual in order to

avoid the risks, for the human body, of injury, electric shock, or fatalities. The manual describes what
special care the operator must take to avoid such risks.

DANGER

IM 12J05D02-01E

This symbol indicates that the operator must refer to the instructions in this manual in order to prevent

WARNING

CAUTION

the instrument (hardware) or software from being damaged, or a system failure from occurring.

This symbol gives information essential for understanding the operations and functions.

This symbol indicates Protective Ground Terminal

This symbol indicates Function Ground Terminal (Do not use this terminal as the protective ground

terminal.)

This symbol indicates Alternating current.

This symbol indicates Direct current.

Warranty and service

Yokogawa products and parts are guaranteed free from defects in workmanship and material under
normal use and service for a period of (typically) 12 months from the date of shipment from the manufac­turer. Individual sales organizations can deviate from the typical warranty period, and the conditions of
sale relating to the original purchase order should be consulted. Damage caused by wear and tear, inad­equate maintenance, corrosion, or by the effects of chemical processes are excluded from this warranty
coverage.

In the event of warranty claim, the defective goods should be sent (freight paid) to the service depart­ment of the relevant sales organization for repair or replacement (at Yokogawa discretion). The following
information must be included in the letter accompanying the returned goods:

• Part number, model code and serial number

• Original purchase order and date

• Length of time in service and a description of the process

• Description of the fault, and the circumstances of failure

• Process/environmental conditions that may be related to the installation failure of the device

• A statement whether warranty or non-warranty service is requested

• Complete shipping and billing instructions for return of material, plus the name and phone number of a
contact person who can be reached for further information.

Returned goods that have been in contact with process fluids must be decontaminated/disinfected before
shipment. Goods should carry a certificate to this effect, for the health and safety of our employees.
Material safety data sheets should also be included for all components of the processes to which the
equipment has been exposed.

IM 12J05D02-01E

Introduction 1-1

WARNINGWARNING

Made in Japan

MODEL
SUFFIX

SUPPLY
OUTPUT

No.

STYLE

DO402G

115VAC

50/60Hz MAX.10VA

0-20mADC or 4-20mADC

1. INTRODUCTION AND GENERAL DESCRIPTION

The Yokogawa EXA is a 4-wire coverter designed for industrial process monitoring, measurement and
control applications. This instruction manual contains the information needed to install, set up, operate
and maintain the unit correctly. This manual also includes a basic troubleshooting guide to answer typi­cal user questions.

Yokogawa can not be responsible for the performance of the EXA analyzer if these instructions are not
followed.

1-1. Instrument Check

Upon delivery, unpack the instrument carefully and inspect it to ensure that it was not damaged during
shipment. If damage is found, retain the original packing materials (including the outer box) and then
immediately notify the carrier and the relevant Yokogawa sales office.

Make sure the model number on the textplate affixed to the top of the display board of the instrument
agrees with your order.

The textplate will also contain the serial number and power supply selection.
Be sure to apply correct power to the unit.

Figure 1-1. Nameplate example

Check that all the parts are present, including mounting hardware, as specified in the option codes at the
end of the model number. For a description of the model codes, refer to Chapter 2 of this manual under
General Specifications.

Basic Parts List: Converter EXA 402
Instruction Manual (See model code for language)
Optional mounting hardware when specified (See model code)

IM 12J05D02-01E

IM 12J05D02-01E

1-2 Introduction

1-2. Application

The EXA converter is intended to be used for continuous on-line measurement in industrial installations.
The unit combines simple operation and microprocessor-based performance with advanced self-diag­nostics and enhanced communications capability to meet the most advanced requirements. The meas­urement can be used as part of an automated process control system. It can also be used to indicate
dangerous limits of a process, to monitor product quality, or to function as a simple controller for a dos­ing/neutralization system.

Yokogawa designed the EXA analyzer to withstand harsh environments. The converter may be installed
either indoors or outside because the IP65 (NEMA 4X) housing and cabling glands ensure the unit is
adequately protected. The flexible polycarbonate window on the front door of the EXA allows pushbut­ton access to the keypad, thus preserving the water and dust protection of the unit even during routine
maintenance operations.
A variety of EXA hardware is optionally available to allow wall, pipe, or panel mounting. Selecting a prop­er installation site will permit ease of operation. Sensors should normally be mounted close to the con­verter in order to ensure easy calibration and peak performance. If the unit must be mounted remotely
from the sensors, WF10 extension cable can be used up to a maximum of 50 metres (150 feet) with a
BA10 junction box.

The EXA is delivered with a general purpose default setting for programmable items. (Default settings
are listed in Chapter 5 and again in Chapter 10). While this initial configuration allows easy start-up, the
configuration should be adjusted to suit each particular application. An example of an adjustable item
is the type of temperature sensor used. The EXA can be adjusted for any one of four different types of
temperature sensors.

To record such configuration adjustments, write changes in the space provided in Chapter 10 of this
manual. Because the EXA is suitable for use as a monitor, a controller or an alarm instrument, program
configuration possibilities are numerous.

Details provided in this instruction manual are sufficient to operate the EXA with all Yokogawa sensor
systems and a wide range of third-party commercially available probes. For best results, read this man­ual in conjunction with the corresponding sensor instruction manual.

Introduction 1-3

1-3. General information

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.
This 4-wire converter is housed in a robust IP65 field mountable case. Two mA outputs, four relays, dig­ital communication and a clear LCD make the DO402G a truly comprehensive package.
The DO402G features PI control on both the auxiliary mA output and the pulse proportional relay out­puts, thus avoiding the need for a separate controller.
The famous EXA sensor diagnostics are now expanded with a logbook facility in combination with the
RS485 two wire communication software option. This can be used to record events like calibration and
diagnostic messages, and to update configuration of the converter remotely.
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.

Features

• Simple 3 Ievel operation

• Display mg/l, ppm, % saturation

• Air calibration or saturated water calibration

• Chloride concentration compensation can be programmed

• Automatic temperature compensation

• Built-in barometric air pressure compensation

• “Hold” function enables fixed output signal during maintenance

• Two separate mA output signals

• Wide flexibility incorporating free programmable range settings, selection of output signals and alarm
functions

• Analog output with adjustable damping time

• Password protection for each programming level

• Built-in wash timer with remote start possibility

• IP65 weather protection

• Universal mounting possibilities

• Sensor diagnostics

• RS 485 bi-directional communication

• Logbook via RS 485 link

• PI control on mA and pulsed contact controls

Method of operation

The EXA DO30 operates on a galvanic cell principle.
The sensor contains a measuring cell consisting of a silver cathode and a lead anode. The voltage gen­erated by this electrode pair is sufficient to generate a spontaneous reduction of oxygen at the cathode,
so no external voltage source for this reaction is required. The electrodes are immersed in an electrolyte
containing potassium hydroxide. Oxygen molecules can pass through a permeable membrane into the
cell. The output current of the cell is directly related to the partial pressure of oxygen at the sample side.
In the sensor a thermistor is integrated to be able to correct for temperature changes. Both signals are
used in the converter to ensure an automatically compensated value for dissolved oxygen. Calibration
is worked out by simple air calibration to make sure that the performance of the instrument will be main­tained.

Display functions and ranges

The display continuously gives you all necessary information at a glance. The process values are shown
in easily readable programmable units. Either mg/l. % saturation or ppm can be chosen.
The user-interface is simplified to a basic set of 6 keys accessible through the flexible window cover. It
uses a simple step by step, question and answer style to communicate with the operator by giving mes­sages on the second line of the display and indicating which keys are to be pressed in the display.

IM 12J05D02-01E

IM 12J05D02-01E

1-4 Introduction

Automatic air calibration

Calibration for a dissolved oxygen instrument is performed by simple air calibration.
Criteria for automatic calibration (stabilization time, DO values) can be set to suit the sensor.
In addition to the air calibration three additional calibration procedures can be used:

1. Span calibration using air saturated water

2. Zero calibration using sulfite saturated water

3. Process calibration using laboratory reference method

Alarm and control functions

The EXA D0402 has four built-in relay contacts. From the factory the first two contacts are pre-defined
as a high or low alarm.
The third contact its pre-defined as a wash contact. This wash contact is driven by a wash-timer with
adjustable wash-time, interval time and relaxation time to control the wash cycle.
The fourth contact is fixed to function as an alarm, indicating that the EXA has found a fault in the meas­uring loop. FAIL safe.

Cleaning

ln combination with the appropriate sensor and immersion type fitting the wash timer with remote start
possibility can be used. Interval-time, washing time and relaxation time are free programmable.

Damping time on output signal

Under certain circumstances disturbances can cause high peaks in the output signal. To avoid these dis­turbances the EXA DO402 has an electronic filtering which averages the output signal during a program­mable period. This damping time is programmable between 0 and 120 seconds.

Salinity compensation

In order to take the effect of salinity into account for oxygen measurement an average chloride concen­tration can be programmed. The chloride concentration value is set manually via the service level. The
EXA D0402 takes account of the effects of salinity and temperature simultaneously. The advantage of
this construction is that the result of the measurement is available immediately. A separate conversion
table is not necessary.

Temperature compensation

The micro-processor makes an accurate temperature compensation possible that performs well over the
entire range of the instrument. No further adjustment tables are required.

Barometric air pressure compensation

Air pressure differences, due to weather conditions or altitude, can cause a variation up to 20 % in the
dissolved oxygen concentration. A built-in air pressure sensor automatically compensates for barometric
influences between 900 to 1100 mbar (90 to 110 kPa).

Sensor diagnostics

The DO sensor is checked for low impedance between the silver electrode and an earth contact in
the liquid, to detect membrane integrity. Temperature sensor connections and sensor connections are
checked for impedance. These faults are signalled by the FAIL contact and can be signalled to the con­trol room by an output of 0/3.5 mA or 22 mA. The fault is also signalled by a special marker held on the
display, a LED on the front and an error code in the message display.
During calibration of a DO measuring system the slope deviation from nominal value (%) and sensor out­put (µA) at 0 mg/l are calculated and checked.
If any of these are outside the limits, an error is signalled.

Logbook

Software record of important events and diagnostic data. Available through RS485, for use with the
Yokogawa PC402 communication software.

Serial Communication

Bi-directional according to the EIA-485 standard using HART-protocol and PC402 software.

Introduction 1-5

1-4. Configuration checklist for DO402

Standard configuration Options Reference for change
Measured variable(s)

Primary inputs D.O. and Temp
DO range 0- 20 mg/l any span within 0-50 mg/l “range”
DO units mg/l ppm. % saturation code 56
Temperature range 0- 50 °C 25 °C minimum span “range”
Temperature unit Celsius Fahrenheit code 11

Outputs

Analog output 4- 20 mA for DO 0-20 mA or 4-20 mA code 30
Second output 4- 20 mA for Temp 0-20 mA or 4-20mA code 30
Output allocation DO and Temp DO, Temp, Table, Pl control code 31
Contact outputs S1= high at 19.5 mg/l (4) freely programmable “setpoint”
S2= low at 1.0 mg/l code 40. 41, 42, 43
Contact allocation mg/l and FAIL mg/l, temp, wash, Pl control, HOLD code 40- 43
Contact variables dead time= 0.2 s; hyst= 0.1 mg/l time: 0- 200 s; hyst 0- 20 mg/l code 44
Add. contact functions none time out alarm code 47
Control functions none Pl on contacts or mA2 output code 45, 46, 34 33
Digital outputs none RS485 code 60

Communication

Digital interface disabled RS485 code 60
Communication software disabled PC402 contact factory
Variables on display mg/l and temp %sat, °C, mA1, mA2, SL, ZR, REL “display”
Burn out disabled burn low (3.5)/ high (22) on mA1/ mA2 code 32
Password protection disabled for mains/ comm./ serv level code 52
Autoreturn return to measure in 10 minutes enable or disable code 50
Add. functions in MAINT disabled wash start/ setpoint adj code 51

Diagnostics

Membrane condition active enable or disable code 02
Check on Slope active enable or disable code 02, 22
Check on zero disabled enable or disable code 02, 21, 22
Check on stability 0.05 mg/l per 60 s 0-50 mg/l in 10-600 s code 20

Compatibility

DO sensor DO30 DOX8, DO410, Ingold code 01, 10
Temperature sensor Pt1000 Pt 100, 22k NTC, PB36 code 10
Membrane thickness 50 µm ( 2 mil) 25 or 50 µm (1 or 2 mil), adj. slope code 01
Sensor principle galvanic galvanic or polarographic code 01, “wiring”
Manual temp. comp. disabled disable or enable code 13

Special Features

Salinity compensation disabled comp. for 0- 100 ppt NaCI code 04
Temperature calibration none adjustment +/- 7.5 °C code 12
Zero calibration disabled disable or enable code 21
Sensor washing disabled
HOLD during maintenance disabled hold last or hold fix “Hold”
Contact during HOLD disabled possible on S1,S2, S3 or S4 code 40-42
Atm. press. compensation active active or manual
Soft fail alarm disabled
Logbook disabled 2 volumes of 50 events code 61,62

interval < 36 hours, wash time 0.1-10 min.

possible for E1..E4, E7..E9, E12, E16, E22

“Wash”

code 53

IM 12J05D02-01E

1-6 Introduction

1-5. System Configuration

1-5-1. Dissolved Oxygen Sensor

The DO402G can be used with a variety of sensors. Some specific programming may be necessary to
match the converter with the sensor.

a. Model DOX8SM sensor

This sensor is a galvanic sensor with a PB36 type temperature compensator and a 25 micron

membrane (1 mil).

This sensor has a nominal output current of 7.5µA in ambient air under reference conditions. In

Service code 01 selection 1 must be programmed when this sensor is used. The membrane check
is inactive with this sensor unless external solution ground is used. ( metal holder or sample line )

b. Model DO30G sensor

This sensor is essentially the same as the DOX8SM sensor, but it has a 50 micron membrane,

fixed sensor cable, Pt1000 RTD temperature compensation and integral solution ground that allows
membrane checking. The nominal output of this sensor is 3.75 µA in air under reference conditions.
In Service item ”*I.CELL” selection 0 must be programmed when this sensor is used.

For details, refer to GS12J05D03-01E.

c. Model DO30 sensor

This sensor is specified in GS12J6K4 and it can be supplied with 50 or with 25 micron membrane.

Normally 50 micron membrane is used and no reprogramming is necessary. Otherwise Service
code 01 setting must be changed from 0 to 1.

d. Ingold model 32 sensors with 12, 19 and 25 mm shaft

These sensors are available in many different configurations. The sensor is a polarographic sensor

and therefore settings of service code 01 has to be changed from 0 to 1.

The sensor output is normally between 30 and 100 nA in ambient air under reference conditions,

but the “large cathode” version has a current output between 200 and 700 nA. To utilize Slope
diagnostic features, it is best to read current output during first air calibration in “display” mode and

to enter that value in service code 01.
The temperature compensator is a NTC resistance and that can be chosen by entry of 3 in code 10.
The wiring of the sensor is different as well:
The red wire: the anode goes to terminal 18
The white wire: the cathode goes to terminal 17
The green/yellow wire: the shield goes to terminal 14 and the 2 black wires for NTC go to terminal

11 and 12.
The membrane checking feature cannot be used for these sensors, due to the construction of the

sensor.

1-5-2. The holders

a. PB30 floating ball holder

All Yokogawa sensors are compatible with the floating ball holder that is specified in GS12J6K4

and GS12J5A1.

b. FD30 immersion fitting

The DO30 sensor is compatible with the FD30 immersion holder as specified in GS12J6K4 and with

all flow fittings and flow fitting subassemblies that are specified in GS12D7K2.

c. DOX8HS submersion type holder

The DOX8SM and the DO30G sensor are compatible with the DOX8HS holder and all PH8 model

holders.

IM 12J05D02-01E

2. DO402G SPECIFICATIONS

2-1. General
A. Input specifications

: The DO402G Dissolved Oxygen

converter measures the cur­rent, that is generated by the
Dissolved Oxygen sensor. The
flexibility of the input circuit
allows the use of many com­mercially available sensors,
whether they are of the Galvanic
type (driving voltage generated
internally) or Polarographic type
(driving voltage supplied by con­verter)
The 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
RTD elements or PB36 as used
in DOX8 and DO30 sensors, as
well as the 22 k NTC as used by
the Hamilton Oxyferm.

B. Input ranges

- DO : 0- 50 mg/l (ppm)

- Temperature

C. Span

- DO concentration
: minimum: 1 mg/l (ppm)
maximum: 50 mg/l (ppm)

- % saturation

- Temperature

D. Transmission Signals

: Two isolated outputs of 0/4- 20

: 0- 50 ºC (32- 122 ºF)

: minimum: 10 %

maximum

: minimum: 25 ºC (77 ºF) minimum: 25 ºC (77 ºF)minimum: 25 ºC (77 ºF)

maximum

mA DC with common nega­tive. Maximum load 600 Ohm.
Auxiliary output can be chosen
from Temperature, DO, PI con­trol, table, burn up (22 mA) or
burn down (0 or 3.5 mA) to sig­nal failure

: 300 %
: 50 ºC (122 ºF)

Specification 2-1

E. Temperature compensation

: 0- 50 ºC

Sensor types: Pt100 or Pt1000
RTD; PB36 (Yokogawa compat­ible);
22 k NTC (Ingold compatible)
Automatic or Manual tempera­ture compensation

F. 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

Possible calibration routines are:

- Slope (span) calibration in
ambient air. The calibration
table is based on 70 % RH and
is determined empirically.

- Slope (span) calibration in- Slope (span) calibration in
water, saturated with air:
according ISO 5814

- Zero calibration (normally inac­tive)

G. Serial Communication

: Bi-directional according to the

EIA-485 standard using HART
protocol and PC402 software.

H. Logbook

: Software record of important

events and diagnostic data.
Available through RS485, with
key diagnostic information avail­able in the display.

I. Display

: Custom liquid crystal display,

with a main display of 31/2 digits

12.5 mm high. Message display
of 6 alphanumeric characters, 7
mm high.

IM 12J05D02-01E

IM 12J05D02-01E

2-2 Specification

J. Contact outputs

- General : Four (4) SPDT relay contacts
with LED indicators. For S1,
S2, and S3, the LED is on
when relay is powered.
NOTE:
For S4 (FAIL) LED lights when
power is removed (Fail safe).

Contact outputs configurable

for hysteresis and delay time.

- Switch capacity

: Maximum values 100 VA,

250 V AC, 5 Amps.
Maximum values 50 Watts,
250 V DC, 5 Amps.

- Status : High/Low process alarms,
selected from process
parameters and temperature.
Contact output is also available
to signal “Hold Active”

- Control function

: On/Off
PI pulsed Proportional duty cycle control

with integral term.

PI frequency Proportional frequency control

with integral term. In addition
wash cleaning control signal on
S3, and FAIL alarm for system
and diagnostic errors on S4

K. Contact input : Remote wash cycle start.

L. Power supply

Supply voltage rating

: 100, 115, 230 VAC

Applicable range

: �5 to 115, ��.� to 132.2, �5 to 115, ��.� to 132.2,�5 to 115, ��.� to 132.2,

1�5.5 to 264.5 VAC

Supply frequency rating

: 50 / 60 Hz

Applicable range

: 50 Hz ± 5% / 60 Hz ± 5%

Power consumption

: Maximum 10 VA for steady

operation

M. Safety and EMC conforming standards

Safety : conforms to EN 61010-1,

CSA C22.2 No.1010.1 certified

EMC : conforms to EN61326 Class A

(Note 1), EN61000-3-3 ,
AS/NZS CISPR 11

Category based on IEC 61010: II (Note 2)
Pollution degree based on IEC 61010:2 (Note

2)

Installation altitude: 2000 m or less

Note 1:

Note 2:

N. Shipping details

: Package size w x h x d

2-2. Operating specifications

A. Performance : DO (at t process = 25 °C)

- Linearity : ± 0.03 mg/l or ± 0.5%FS,

- Repeatability: ± 0.03 mg/l or ± 0.5%FS,

- Accuracy : ± 0.05 mg/l or ± 0.5%FS,

B. Performance : Temperature (Pt1000, PB36,

22kNTC)

- Linearity : ± 0.3 ºC

- Repeatability : ± 0.1 ºC

- Accuracy : ± 0.3 ºC

Performance : Temperature (Pt100)

- Linearity : ± 0.4 ºC

- Repeatability : ± 0.1 ºC

- Accuracy : ± 0.4 ºC

Note on performance specifications:

The specifications are expressed with sim-

ulated inputs, because the DO402G can
be used with many different sensors with
their unique characteristics.
The following tolerance is added to above
performance.
mA output tolerance : ± 0.02 mA of
"0/4 - 20 mA"
Digital display tolerance : +1 digit

C. Response time

0- �0% : 10 s

D. Ambient operating temperature

: -10 to +55 �C (14 to 131 ºF)�C (14 to 131 ºF)C (14 to 131 ºF)

This instrument is a Class A product,
and it is designed for use in the
industrial environment. Please use
this instrument in the industrial
environment only.
Installation category, called over­voltage category, specifies impulse
withstand voltage. Category II is for
electrical equipment.
Pollution degree indicates the degree
of existence of solid, liquid, gas or
other inclusions which may reduce
dielectric strength. Degree 2 is the
normal indoor environment.

2�0 x 300 x 2�0 mm.

11.5 x 11.� x 11.5 in.
Packed weight approx.

2.5 kg (5lb).

whichever is greater
whichever is greater
whichever is greater

Specification 2-3

E. Storage temperature

: -30 to +�0 �C (-22 to 15� ºF)�C (-22 to 15� ºF)C (-22 to 15� ºF)

F. Humidity : 10 to �0% RH non-condensing
G. Housing

Case : Cast aluminium with chemically

resistant coating
Cover : flexible polycarbonate window.
Case color : off-white
Cover color : moss green.
Cable entry :
Cable terminals:

via six Pg13.5 nylon glands.

for up to 2.5 mm2 finished wires.

Protection : weather resistant to IP65 /

NEMA 4X / CSA Type 3S
standards.

Mounting : Pipe, wall or panel, using

optional hardware.

H. Data protection

:

Non volatile memory for
configuration and logbook, and
lithium battery for clock support.

I. Watchdog timer

: Checks microprocessor

2-3. Model and suffix codes

[Style: S3]

Model

DO402G ----------------- --------- Dissolved Oxygen

Type -1 --------- General
Power Supply

Voltage

Language -J-E---------

Options

Suffix
code

-1

-2

-5

Mounting Hardware

Tag Plate

Conduit Adapter

Hood

Option
code

---------

---------

---------

---------

/U

/PM

/H3

/H4

/SCT
/AFTG
/ANSI
/X1

Description

Converter

115V +/-15% AC, 50/60 Hz
230V +/-15% AC, 50/60 Hz
100V +/-15% AC, 50/60 Hz

Japanese
English

Pipe, wall mounting
bracket (Stainless steel)
Panel mounting bracket
(Stainless steel)
Hood for sun protection
(Carbon steel)
Hood for sun protection
(Stainless steel)
Stainless steel tag plate
G 1/2
1/2 NPT
Epoxy baked finish (*1)

*1 The housing is coated with epoxy resin.

J. Automatic safeguard

: Return to measuring mode

when no keystroke is made
for 10 min.

K. Power interruption

:

Less than 50 milliseconds no

effect.

L. Operation protection

:

3-digit programmable password.

IM 12J05D02-01E

Installation and wiring 3-1

184

144

72

20

144

220

23

112

Four M6 screws, 8 (0.31) deep

80

80

36 36

36

38

A B C

D

E F

□ Hood (optional)

Option code : /H

□

Cable inlet port (21 (0.83) dia. holes)
DIN PG13.5 cable gland

Ground terminal

(M4 screw)

Weight: Approx. 2 kg

A : Spare (can be used for contact input separately)
B : For sensor cable
C : For output signal
D : For contact output (S3 and S4)
E : For contact output (S1 and S2)
F : For power supply

Adaptor for conduit work
(option code : /AFTG, /ANSI)

Unit: mm (inch)

Approx. 55

Adaptor

G 1/2 female ( / AFTG)

1/2 NPT female ( / ANSI)

49

(7.24)

(8.66)

(3.15)

(3.15)

(1.93)

(2.17)

(5.67)

(5.67)

(2.83)

(0.79)

(0.91)

(4.41)

(1.42)

(1.42)

(1.42)

(1.50)

WARNINGWARNING

3. InstallatIon and WIrIng

3-1. Installation and dimensions
3-1-1. Installation site

This instrument is a Class A product, and it is designed for use in the industrial environment. Please use
this instrument in the industrial environment only.

The EXA converter is weatherproof and can be installed inside or outside. It should, however, be
installed as close as possible to the sensor to avoid long cable runs between sensor and converter. In
any case, the cable length should not exceed 50 meters (162 feet). Select an installation site where:

• Mechanical vibrations and shocks are negligible

• No relay/power switches are in the direct environment

• Access is possible to the cable glands (see figure 3-1)

• The converter is not mounted in direct sunlight or severe weather conditions

• Maintenance procedures are possible (avoiding corrosive environments)
The ambient temperature and humidity of the installation environment must be within the limits of the

instrument specifications. (See chapter 2).

3-1-2. Mounting methods

Refer to figures 3-2 and 3-3. Note that the EXA converter has universal mounting capabilities:

• Panel mounting using optional brackets

• Surface mounting on a plate (using bolts from the back)

• Wall mounting on a bracket (for example, on a solid wall)

• Pipe mounting using a bracket on a horizontal or vertical pipe (maximum pipe diameter 50 A)

Figure 3-1. Housing dimensions and layout of glands

IM 12J05D02-01E

3-2 Installation and wiring

M6, 4 screws

100

178

137

+2
0

137

+2
0

12 max.(panel thickness)

23

Panel cutout dimensions

(7.01)

(0.91)

(0.47)

(5.43)

(5.43)(3.94)

M5, 2 screws

188

174

50

200

100

M6, 4 screws

135 13

224

M6, 4 screws

200

35
15

70
100

10mm dia., 3 holes

Nominal 50A (O.D 60.5mm)
mounting pipe

Example of bracket used for pipe mounting

Example of bracket used for wall mounting

(7.40)

(6.85)

(1.97)

(5.31) (0.51)

(8.82)

(7.87)

(1.38)

(0.59)

(2.76)

(3.94)

(0.39)

(7.87)

(3.94)

(2 inch)

Figure 3-2 . Panel mounting diagram (Option Code: /PM)

Unit: mm (inch)

Figure 3-3. Wall and pipe mounting diagram (Option Code: /U) (Option Code: /U)

IM 12J05D02-01E

Installation and wiring 3-3

DANGERDANGER

WARNINGWARNING

Figure 3-4. Internal view of EXA wiring compartment

• Never apply power to the DO402G converter and other instruments connected to the DO402G
converter until all wiring is completed.

• This product complies with the CE marking and CSA certified.

Where compliance with the CE marking and relevant standard is necessary, the following wiring is

required.

1. Install an external switch or circuit breaker to the power supply of the DO402G converter.

2. Use an external switch or circuit breaker rated 5A and conforming to IEC 60947-1 or IEC 60947-3.

3. It is recommended that the external switch or circuit breaker be installed in the same room as the
DO402G converter.

4. The external switch or circuit breaker should be installed within reach of the operator and identified
with marking as a power supply switch to the DO402G converter.

5. Power lines such as power cables and contact outputs should be fixed securely onto a wall or
construction using cable racks, conduit tubing, nylon bands or other appropriate ways. Accidental
removal from terminals by pulling may result in electric shock.

IM 12J05D02-01E

3-4 Installation and wiring

WARNING

12D7C3-04

GLANDS TO BE

USED FOR CABLING

3-2. Preparation

Refer to figure 3-4. The relay contact terminals and power supply connections are under the screening
(shielding) plate. These should be connected first. Connect the sensor, outputs and data communication
connections last.

To open the EXA 402 for wiring:

1. Loosen the four frontplate screws and remove the cover.

2. Use the rubber knob in the lower right hand corner and swing open the display board to the left.

3. The upper terminal strip is now visible.

4. Remove the screen (shield) plate covering the lower terminal strip.

5. Connect the power supply and contact outputs. Use the three glands at the back for these cables.

6. Replace the screen (shield) plate over the lower terminals.

Always replace the screen plate over the power and contact outputs for safety and to avoid interference.

7. Connect the analog output(s), the sensor input, and, if necessary, the RS485 serial bus.

8. Use the front three glands for analog output, sensor input, contact input and communication cabling
(see figure 3-5).

9. Close the display board and switch on the power. Commission the instrument as required or use the
default settings.

10. Replace the cover and secure frontplate with the four screws.

Tighten four frontplate screws to 1.5 N·m torque.

Contact

(S3,S4,FAIL)

output cables

Suitable for cables with an outside diameter between 6 - 12 mm (0.24 - 0.47 in.)

Figure 3-5. Glands to be used for cabling

Communi-

cation,

contact

input

Contact
(S1,S2)

output
cables

High voltage section

Sensor

cables

Power

cable

Analog

output
cables

IM 12J05D02-01E

Installation and wiring 3-5

DANGER

FRONT GLANDS

Figure 3-6. System configuration

3-3. Wiring the power supply

Sensor

Output
signals

RS485

Contact intput

Power

Contact
output

Contact
output

REAR GLANDS

S1

S2

S3

S4/FAIL

3-3-1. General precautions

Make sure the power supply is switched off. Also, make sure that the power supply is correct for the
specifications of the EXA and that the supply agrees with the voltage specified on the textplate. Remove
the front cover by unscrewing the four screws to check this textplate on the top of the display board.

Local health and safety regulations may require an external circuit breaker to be installed. The instru­ment is protected internally by a fuse. The fuse rating is dependent on the supply to the instrument. The
250 VAC fuses should be of the “time-lag” type, conforming to IEC60127.
The internal fuse is located next to the power terminals (in the lower right hand corner).

Use only a fuse of the specified current, voltage and type ratings to prevent fire. For fuse replacement,
refer to Section 7-3, “Fuse Replacement.”

3-3-2. Access to terminal and cable entry

Terminals 1 and 2 on the bottom terminal strip are used for the power supply. Guide the power cables
through the gland closest to the power supply terminals. The terminals will accept wires of 2.5 mm2 (14
AWG). Use cable finishings if possible.

Connect the wires as indicated in the wiring diagram (refer to figure 3-6).

IM 12J05D02-01E

3-6 Installation and wiring

DANGER

CAUTION

71

S4

S3

S2

S1

C NC NO

72 73 51 52 53 41 43 31 3342 32

FUSE

100
115
230

250VAC; T

3 12

C NC NO C NC NO C NC NO

VAC
VAC
VAC

200 mA
200 mA
100 mA

Relay Contacts

Power Supply

1213

1516

63 66 65 62 61 95 94 93 92 91

SCREEN

mA2

mA1

SCREEN

TL TL

17 11

Sensor Inputs mA Outputs

Digital
Communications

Contact
Input

CONT SENSOR mA OUTPUT RS485

14

22

21

- - - polarographic sensor galvanic sensor

High voltage compartment

G N L

18

Liquid

earth

Shield

Temp

SCREEN

99

SCREEN 2

23

250VAC

5A

100VA

250VDC

5A

50W

(M4 screw)

Figure 3-7. Input and output connections

3-3-3. AC power

Connect terminal 1 to the phase line of the AC power and terminal 2 to the zero line. The size of conduc­tors should be at least 1.25 mm2. The overall cable diameter should be between 6 & 12 mm (0.24 & 0.47
in).

3-3-4. Grounding the housing

Protective grounding must be made to prevent electric shock.
To protect the instrument against interference, the housing should be connected to ground by a large

area conductor. This cable can be fixed to the rear of the housing using a braided wire cable. See figure
3-8. This is separated from input ground by a gal­vanic isolation.

Please be sure to connect protective grounding of
DO402G with cable of 1.25 mm2 or larger cross
section in order to avoid the electrical shock to the
operators and maintenance engineers and prevent
the influence of external noise. And further connect
the grounding wire to the

3-3-5. Switching on the instrument

After all connections are made and checked, the
power can be switched on from the power sup­ply. Make sure the LCD display comes on. All
segments will illuminate, then the instrument will
momentarily display its unique serial number. After
a brief interval, the display will change to the meas-

mark (100Ω or less).

ured value. If errors are displayed or a valid meas­ured value is not shown, consult the troubleshooting
section (Chapter 8) before calling Yokogawa.

Figure 3-8. Grounding the housing

IM 12J05D02-01E

Installation and wiring 3-7

WARNING

3-4. Wiring the contact signals

3-4-1. General precautions

The contact output signals consist of voltage-free relay contacts for switching electrical appliances
(SPDT). They can also be used as digital outputs to signal processing equipment (such as a controller or
PLC). It is possible to use multi-core cables for the contact in and output signals and shielded multi-core
cable for the analog signals.

3-4-2. Contact outputs

The EXA unit’s four contact outputs can be wired to suit your own custom requirements (Figure 3-6).
In the Non-Alarm or Power Off states, contacts S1, S2 and S3 are OFF, Common (C) and Normally

Closed (NC) are in contact.
In the “Fail” or Power Off states, contact S4 is ON, Common (C) and Normally Closed (NC) are in con-

tact.
You can either use them to switch AC power, or switch a DC Voltage for digital interfacing.

Default settings

• The contact S1 is pre-programmed for high alarm function.

• The contact S2 is pre-programmed for a low alarm function.

• The contact S3 is pre-programmed for wash function.

• The contact S4 is pre-programmed for FAIL.

The three control contacts (S1 to S3) can be used for simple process control by programming their func­tion (Chapter 5). The FAIL contact is programmed to signal a fault in the measuring loop. Always con­nect the FAIL contact to an alarm device such as a warning light, sound annunciator, or alarm panel to
make full use of the fault detection possibilities (self diagnostics) of the EXA converter.

3-4-3. Contact input

It is necessary to use screening/shielding on the output signal cables. Screw (M3) 23 is used to connect
the shielding.

On resistance: 10Ω or less
Off resistance: 100kΩ or more

IM 12J05D02-01E

3-8 Installation and wiring

3-5. Wiring the analog output signals
3-5-1. General precautions

The analog output signals of the EXA transmit low power standard industry signals to peripherals like
control systems or strip-chart recorders (Figure 3-6).

3-5-2. Analog output signals

The output signals consist of active current signals of either 0-20 mA or 4-20 mA. The maximum load
can be 600 ohms on each.

It should be necessary to use screening/shielding on the output signal cables. Terminal 63 is used to
connect the shielding.

3-6. Wiring the standard galvanic sensor

The sensor cable has markers on the individual wires.
These markings refer to the markers on the terminals.

The temperature compensator has two wires with the markings
T1, T2 and/or 11, 12 and must be connected to terminal 11
and 12.

The measuring electrode: the cathode is marked with IE and/or 13
and must be connected to terminal 13.
The reference electrode: the anode is marked with RE and/or
15 and must be connected to terminal 15.
The liquid earth ( solution ground) is marked with 16 and must
be connected to terminal 16.
Note:
The liquid earth (solution ground) connection is valid

only when the floating ball holder, Model PB350G or
PB360G, is used. Otherwise, do not make a connection
to terminal 16. The connection, if made, may result in
abnormal readings. Even if the floating ball holder is

Figure 3-9. Cable gland assembly

used, when the liquid earth (solution ground) connection is not used, then disconnect the wiring
to terminal 16. (The disconnected wire should be covered with an insulating tube to avoid contact

with other terminals.)
The overall shield of the cable is marked with 14 and must be connected to terminal 14.
Note:
Always interconnect terminal 13 and 17 to reduce noise voltage onto measurement.

3-7. Wiring other galvanic sensors

Consult the users manual for the color identification of the sensor cable and connect temperature com­pensator, cathode and anode to the terminals: 11, 12, 13 and 15 as described above.
Connect the cable shield to 14 if there is one available. Sensor diagnostics is normally not possible.
Note:
Always interconnect terminal 13 and 17 to reduce noise voltage onto measurement.

3-8. Wiring polarographic sensors

Consult the owners manual for the color identification of the sensor cable and connect temperature com­pensator, cathode and anode to terminals 11, 12, 17 and 18 in this sequence.
Connect the cable shield (when provided) to terminal 14.

Note:
A shorting cable is connected between converter terminals 13 and 17.
When a polarographic sensor is to be connected, the cable is not used, so disconnect it.

It is recommended to save the shorting cable for future use—if may be needed when a galvanic sen-

sor is used.

3-9. Wiring RS485 signal

It is necessary to use screening/shielding on the output signal cables. Screw (M3) 99 is used to connect
the shielding.

IM 12J05D02-01E

Operation 4-1

4. OPERATION; DISPLAy FUNCTIONS AND SETTING

4-1. Operator interface

This section provides an overview of the operation of the EXA operator interface. The basic procedures
for obtaining access to the three levels of operation are described briefly. For a step-by-step guide to
data entry, refer to the relevant section of this instruction manual. Figure 4-1 shows the EXA operator
interface.

LEVEL 1: Maintenance

These functions are accessible by pushbutton through a flexible front cover window. The functions make
up the normal day-to-day operations that an operator may be required to complete. Adjustment of the
display and routine calibration are among the features accessible in this way. (See table 4-1).

LEVEL 2: Commissioning

A second menu is exposed when the EXA front cover is removed and the display board is revealed.
Users gain access to this menu by pressing the button marked * in the lower right of the display board.
This menu is used to set such values as the output ranges and hold and wash features. It also gives
access to the service menu. (See table 4-1).

LEVEL 3: Service

For more advanced configuration selections, press the button marked * , then press “NO” repeatedly
until you reach *SERV. Now push the “YES” button. Selecting and entering “Service Code” numbers in
the commissioning menu provide access to the more advanced functions. An explanation of the Service
Codes is listed in chapter 5 and an overview table is shown in chapter 10.

Table 4-1. Operations overview
Routine Function Chapter

Maintenance AIR. CAL Calibration in air ( preferred method) 6
(level 1) H2O. CAL Calibration in aerated water 6
MAN. CAL Process calibration based on grab sample 6
DISP Read auxiliary data and set message display 4
HOLD Switch HOLD on/off *) 5
SETP Adjust alarm setpoints *) 5
WASH Start wash cycle manually *) 5
M.TEMP Adjust manual temp*) 5
M.PRESS Adjust manual press 5
Commissioning *SETP Adjust alarm setpoints 5
(level 2) *RANGE Adjust output range(s) 5
*HOLD Activate HOLD function 5
*WASH Activate and configure the wash timer 5
Service *SERV Configure the specialized functions of the converter 5
(level 3)

)

Only possible if activated

*
NOTE:

All three levels may be separately protected by a password. See Service Code 52 in chapter 5

Service Code table for details on setting passwords.

IM 12J05D02-01E

IM 12J05D02-01E

4-2 Operation

HOLD FAIL

YES NO

ENT

SETPOINTS
RANGE
SET HOLD

SERVICE

MEASURE

H2O.CAL
DISPLAY

HOLD

NO MODEYES

ENT

S1

S2

WASH/S3

FAIL/S4

YOKOGAWA

MODE

AIR.CAL

WASH

TEMP.MAN.

CONTACTS

MARKINGS

WITHIN

ENCLOSURE

MAN.CAL

12J6B2-04

FRONT EXA DO402

Output hold flag

Main display

Message display

Key prompt flags

Selection keys
YES : Accept setting
NO : Change setting

Adjustment keys
> : Choose digit to

adjust

^ : Adjust digit
ENT : Confirm change

Figure 4-1. DO402 operator interface

Manual temperature
compensation flag

Fail flag

Broken line indicates area
that can be seen through
front cover

Menu pointer flags

Commissioning
function menu

Commissioning
mode access key

Relay contact
status indicators

Measure/Maintenance
mode key

4-2. Explanation of operating keys
MODE key This key toggles between the Measuring and Maintenance modes. Press once to obtain

access to the maintenance function menu. (Level 1 see table 4-1)
Press again to return to the Measuring mode (press twice when hold is activated).

yES/NO keys These are used to select choices from the menu.

YES is used to accept a menu selection.
NO is used to reject a selection, or to move ahead to the next option.

DATA ENTRy keys ( ENT)

is used as a “cursor” key. Each press on this key moves the cursor or flashing digit
one place to the right. This is used to select the digit to be changed when entering
numerical data.

is used to change the value of a selected digit. Each press on this key increases

the value by one unit. The value can not be decreased, so in order to obtain a
lower value, increase past nine to zero, then increase to the required number.

ENT

When the required value has been set using the > and ^ keys, press ENT to con­firm the data entry. Please note that the EXA 402 does not register any change of
data until the ENT key is pressed.

* key This is the Commissioning mode key. It is used to obtain access to the Commissioning

menu. This can only be done with the cover removed or opened. Once this button has
been used to initiate the Commissioning menu, follow the prompts and use the other
keys as described above.

Operation 4-3

4-3. Setting passcodes

In Service Code 52, EXA users can set passcode protection for each one of the three operating levels,
or for any one or two of the three levels. This procedure should be completed after the initial commis­sioning (setup) of the instrument. The passcodes should then be recorded safely for future reference.

When passcodes have been set, the following additional steps are introduced to the configuration and
programming operations:

Maintenance

Press MODE key. The display shows 000 and *PASS*
Enter a 3-digit passcode as set in Service Code 52 to obtain access to the Maintenance Mode

Commissioning

Press * key. The display shows 000 and *PASS*
Enter a 3-digit passcode as set in Service Code 52 to obtain access to the Commissioning Mode.

Service

From the commissioning menu, select *SERV by pressing YES key. The display shows 000 and *PASS*
Enter a 3-digit passcode as set in Service Code 52 to obtain access to the Service Mode.

NOTE:
See Service Code 52 for the setting of passcodes.

IM 12J05D02-01E

4-4 Operation

YES

YES

NO

MODE

NO

YES

YES

NO

NO

YES

NO

YES NO

YES NO

DISPLAY

HOLD

AIR.CAL

H2O.CAL

NO

NO

NO

NO

NO

NO

NO

NO

YES

YES

NO

YES

NO

YES

NO

YES

NO

YES

NO

YES

NO

YES

NO

YES

NO

DISPLAY

DISPLAY

DISPLAY

DISPLAY

DISPLAY

DISPLAY

DISPLAY

DISPLAY

MAN.CAL

YES

NO

NO

NO

YES

NO

NO

YES

NO

NO

YES

NO

NO

YES

NO

(See H2O
calibration
Chapter 6)

MEASURE
H2O.CAL
DISPLAY

HOLD

AIR.CAL

When enabled in
Hold (SET HOLD)
mode.

Manual press.
when enabled
in service code 51

(See Manual
calibration
Chapter 6)

Process

temperature

Barometric

pressure

Software release

number

Slope

Cell current

Manual press.
when enabled
in service code 51

Display Access

% Saturation

Current

output 1

Manual temp.
when enabled
in service code 13

Manual press.
when enabled
in service code 51

(Note 1)

(Note 2)

MAN.CAL

(See Air
calibration
Chapter 6)

Note 1: Manual temperature compensation menu

The menu can be displayed in maintenance mode.
This can be done by enabling the function in Service Code 13.
Manual temperature compensation menu is displayed and
temperature can be entered manually.

Note 2: Pressure is in bars.

Default: 1.013 bar

Setting range: 0.500 to 5.000 bar

Current
output 2

Press YES to fix

the selected second

line of display

4-4. Display functions (default)

IM 12J05D02-01E

Parameter setting 5-1

5. PARAMETER SETTING

5-1. Maintenance mode

Standard operation of the EXA instrument involves use of the maintenance (or operating) mode to set up
some of the parameters.

Access to the Maintenance mode is available via the six keys that can be pressed through the flexible
window in the instrument cover. Press the MODEkey once to enter this dialog mode.

NOTE:
At this stage the user will be prompted for pass code where this has been previously set up in

service code 52 in chapter 5.

Air calibration See “calibration” section 6.
AIR.CAL

H20 calibration See “calibration” section 6.
H2O.CAL

Display See “operation” section 4.
DISP

Setpoint Select and adjust setpoint (when enabled in service menu section 5, service
SETP

Wash Manually start/stop wash cleaning (when enabled in service menu section 5,
WASH

Hold Manually switch on/off HOLD (when enabled in commissioning menu section).
HOLD

code 51). See adjustment procedure 5-4.

service code 51). See adjustment procedure 5-3.

See adjustment procedure 5-2.

IM 12J05D02-01E

IM 12J05D02-01E

5-2 Parameter setting

AIR.CAL

YES

NO

MODE

NO

NO

NO

NO

YES

NO

YES

HOLD

Note: The HOLD feature must first be activated in the commissioning mode section 5.--

YES

NO

MEASURE

SETPOINTS
RANGE
SET HOLD

SERVICE

MEASURE

NO MODEYES

ENT

S1

S2

WASH/S3

FAIL/S4

YOKOGAWA

MODE

WASH

CONTACTS

MARKINGS

WITHIN

ENCLOSURE

YES

NO

NO

5-1-1. Manual activation of Hold

Note: The HOLD feature must first be activated in the commissioning mode section 5-2-3.

5-1-2. Manual Wash start/stop

NO

YES

AIR.CAL

YES

NO

MODE

NO

NO

NO

NO

NO

NO

NO

YES

NO

YES

YES

MODE

YES

NO

Note: Wash must first be switched on in commissioning mode section 5.5.
and set for adjustment in the maintenance mode, by service code 5.1.

WASH ACTIVE press YES
to stop.

YES

SETPOINTS
RANGE
SET HOLD

SERVICE

MEASURE

NO MODEYES

ENT

S1

S2

WASH/S3

FAIL/S4

YOKOGAWA

MODE

WASH

CONTACTS

MARKINGS

WITHIN

ENCLOSURE

Parameter setting 5-3

Note:
Relay S3 must first be set for “WASH” in service code 42
Manual wash start/stop is enabled with Service code 51.
Refer to commissioning mode section 5-2-4 for automatic cycle timing setup.

Manual temperature adjustment menu is added to the maintenance mode

Manual temperature adjustment is only visible if the manual temperature
When the manual temperature is entered, set the manual temperature and press enter.

in service code 13 is enabled.

IM 12J05D02-01E

IM 12J05D02-01E

5-4 Parameter setting

NO

YES

YES

NO

MODE

NO

YES

YES

NO

YES

NO

YES

NO

YES

YES

For adjustments,
follow procedures
as in section 5-2-1.

For adjustments,
follow procedures
as in section 5-2-1.

Setpoint 3 and 4
when enabled in

service codes

42 and 43

Setpoint analogue

control output (mA2)

when enabled in code 31

Note: To enable adjustment of setpoints in
maintenance mode, Service Code 51
must be set to "ON".
Setpoints available will depend on their
configuration in the Service Code.

SETPOINTS
RANGE
SET HOLD

SERVICE

MEASURE

NO MODEYES

ENT

S1

S2

WASH/S3

FAIL/S4

YOKOGAWA

MODE

WASH

CONTACTS

MARKINGS

WITHIN

ENCLOSURE

AIR.CAL

NO

NO

NO

NO

NO

5-1-3. Setpoint adjustment

Parameter setting 5-5

5-2. Commissioning mode

In order to obtain peak performance from the EXA converter, you must set it up for each custom applica­tion. Refer to section 1-4 for standard configurations and options.

*SETP Alarms are set by default S1 - high process alarm

S2 - low process alarm
S3 - WASH
S4 - FAIL

The setpoints are at arbitrary default value. Therefore, you must set these to

meaningful values, or set them to off. (See service codes 40 to 49 and user
interface codes 50 to 59).

*RANGE mA output 1 is set as default to 0 - 20 mg/l

mA output 2 is set as default to 0 - 50 °C

For enhanced resolution in more stable measuring processes, it may be desir-

able to select 0 - 5 mg/l range, for example, and maybe 0 - 25 °C temperature
range.
Service codes 30 to 39 can be used to choose other output parameters on mA
output 2.

*HOLD The EXA converter has the ability to “hold” the output during maintenance peri-

ods. This parameter should be set up to hold the last measured value, or a fixed
value to suit the process.

*WASH The EXA can be set up to control a wash cleaner. When using this function, the

timings must be configured for interval, wash and recovery periods.

*SERV This selection provides access to the service menu.

What follows are pictorial descriptions of typical frontplate pushbutton sequences for each parameter set­ting function. By following the simple YES/NO prompts and arrow keys, users can navigate through the
process of setting range, setpoints, hold, wash and service functions.

IM 12J05D02-01E

IM 12J05D02-01E

5-6 Parameter setting

ENT

ENT

ENT

ENT ENT

ENT

ENT

ENT

repeated
keystrokes

YES

NO

NO

NO

NO

NO

NO

NO

YES

NO

YES

NO

YES

YES

NO

YES

NO

YES

NO

YES

NO

YES

NO

SETPOINTS
RANGE
SET HOLD

SERVICE

MEASURE

H2O.CAL
DISPLAY

HOLD

MODE

AIR.CAL

WASH

MAN.CAL

5-2-1. Setpoints

ENT

Adjust setpoint value
using > ENT keys
as shown for setpoint 1.

>

YES

NO

YES

NO

YES

NO

NO

NO

NO

Process Alarms on
S3 and S4 are
only available when
enabled in Service
Codes 40-49

Analogue control setpoint
is only available when
enabled in Service Code 31

ENT

YES NO

ENT

ENT

Setpoint confirmed­return to commissioning
menu.

YES

Parameter setting 5-7

IM 12J05D02-01E

IM 12J05D02-01E

5-8 Parameter setting

YES

NO

YES

NO

NO

NO

NO

NO

NO

YES

YES

NO

YES

ENT

YES

NO

See facing

page

ENT

ENT

ENT

ENT

ENT

ENT

ENT

ENT

YES

NO

YES

NO

YES

NO

YES

NO

SETPOINTS
RANGE
SET HOLD

SERVICE

MEASURE

H2O.CAL
DISPLAY

HOLD

MODE

AIR.CAL

WASH

MAN.CAL

5-2-2. Range

Parameter setting 5-9

YES

NO

YES

NO

NO

YES

NO

NO

ENT

ENT

ENT

ENT

ENT

OR

YES

ENT

ENT

YES

ENT

YES

NO

YES

NO

YES

NO

YES

NO

YES

NO

Choose Range to adjust, then set begin scale (0%)
and end scale (100%) of the mA output signal, using the >,
,and ENT keys. Selection of mA output(0-20 / 4-20 mA) is
in Service Code 30.

Note: Range 2 does not appear
when PI control or table set
on mA2

Range Selection Options
are determined by Service
Code 31

Range values set, returnto
commission mode.

>

IM 12J05D02-01E

IM 12J05D02-01E

5-10 Parameter setting

YES

NO

YES NO

YES

NO

YES

NO

YES

NO

YES

NO

YES

NO

NO

NO

NO

NO

NO

YES

YES

NO

YES

NO

YES

NO

YES

NO

YES

YES

NO

HOLD active
last measured
value.

HOLD deactivated, return
to commissioning menu.

YES

HOLD

SETPOINTS
RANGE
SET HOLD

SERVICE

MEASURE

H2O.CAL
DISPLAY

HOLD

MODE

AIR.CAL

WASH

MAN.CAL

5-2-3. Hold

Parameter setting 5-11

YES

NO

ENT

HOLD

HOLD

HOLD HOLD

HOLD

ENT

HOLD

ENT

ENT

ENT

ENT

ENT

Set HOLD "fixed value"
for mA2.

YES

Set HOLD "fixed value"
for mA1.

HOLD values set,return
to commissioning menu.

IM 12J05D02-01E

IM 12J05D02-01E

5-12 Parameter setting

YES

NO

YES

NO

YES

NO

YES

NO

YES

NO

YES

NO

YES

NO

NO

NO

NO

NO

NO

YES YES

(NOTE: The menu item "WASH"
will not appear unless selected in
Service Code 42)

NO

YES

NO

Wash system timings
are set with the >, ,
and ENT keys in the
setpoint menu

>

ENT

ENT

ENT

ENT

ENT

ENT

SETPOINTS
RANGE
SET HOLD

SERVICE

MEASURE

H2O.CAL
DISPLAY

HOLD

MODE

AIR.CAL

WASH

MAN.CAL

5-2-4. Wash

5-2-5. Service

ENT

YES

NO

YES

NO

YES

NO

YES

NO

YES

NO

NO

NO

NO

NO

NO

SETPOINTS
RANGE
SET HOLD

SERVICE

*

MEASURE

MAN.CAL
DISPLAY
HOLD

MODE

AIR.CAL

WASH

ENT

ENT

ENT

YES

ENT

ENT

Example: Service Code 01

Select Sensor Type

for galvanic sensor

for polarographic
With the >, ,ENT keys

>

ENT

H2O.CAL

ENT

ENT

>

Nominal cell current at

100% Saturation.

Set using >, ,ENT keys.

Note:
For information on how to set cell
current, see description in Section
1-5, A4

Parameter setting 5-13

IM 12J05D02-01E

IM 12J05D02-01E

5-14 Parameter setting

5-3. Notes for guidance in the use of service coded settings

5-3-1. Parameter specific functions

Code 01 *S.TYPE Select 0 for DO30 sensor or other galvanic sensor. Select 1 for SM31 and

other polarographic sensor.

*I.CELL After selecting sensortype you need to select the nominal cell current. With a

galvanic sensor 3 choices are offered.

Select 0 for DO30 thick (50 µm) membrane with a default of 3.75 µA.

Select 1 for DO30 thin (25 µm) membrane with a default of 7.5 µA.
Select 9 for user definable. This can be set to suit any galvanic sensor.

With polarographic sensor 2 choices are offered.

Select 0 for SM31 sensor with a nominal cell current of 50 nA.
Select 9 for other polarographic sensor, with the nominal cell current to be user
defined.

General Note: Dissolved oxygen sensors fall into two categories – galvanic and

polarographic. Yokogawa offer both types:

Settings for Yokogawa Sensors
DO30 DO30 SM31.
Membrane Thick Thin Sterilizable
*S.TYPE 0 0 1
* I.CELL 0 1 0

Code 02 * CHECK This code is used to set up appropriate diagnostics. In most cases a zero

calibration is not used, the default check, therefore, set to “off”. When zero
check enabled, the maximum permissible zero offset should be set as a signal
current.
When slope check enabled, the maximum as minimum calibrated slope values
should be set as % of the nominal value.
For the galvanic sensors, a membrane check can be enabled. This is an
impedance test to ensure that the membrane is intact.

Code 04 *SAL.TY Set 0 (salinity compensation disabled) when measuring water not including

salinity components. Set 1 (salinity compensation enabled) when manually
calibrated to salinity compensation. This is intended for accurately displaying
saturated % concentration when measuring sample water. Set 1 (salinity
compensation enabled) and then enter NaCl concentration using *[CL-]. For
this concentration, enter salinity concentrations in actual sample water used to
figure out salinity compensation values.

NOTE:
The instrument will not perform salinity compensation simply by setting the

salinity compensation to “1” (enabled) in Code 04, but requires the NaCl
concentration. For measurement in consideration of the salinity of a sample,
first, manually calibrate with values corrected for salinity and enter the NaCl
concentration in Code 04. (See Section 6.4, “Calibration method using manual
calibration method”)

Parameter setting 5-15

Code Display Function Function detail

X Y Z Default values

Parameter Specific functions

01 *S. TYPE Sensor type

Galvanic 0 0
Polarographic 1

*I.CELL Sensor output 0 0

Galvanic 1

User defined

9 3.75 μA

*I.CELL Sensor output

50 nA

0 0

Polarographic

User defined

9 50 nA

02 *CHECK Sensor check

Zero check: disabled

0 0.1.0

Zero check: enabled

1

Slope check: disabled

0

Slope check: enabled

1

Membrane check: disabled/only for Galvanic

0

Membrane check: enabled/only for Galvanic

0 to 19.99 μA for Galvanic*ZERO Maximum permissible
0 to 199.9 nA for PolarographicZero offset

0 to 99.9%*SL.MIN
100 to 400%

0.5 μA

5 nA

40%
200%*SL.MAX

NOT USED

Minimum calibrated slope
Maximum calibrated slope

1 (*1)

03 NOT USED
04 *SAL.TY Salinity comp.(*2) Compensation disabled 0 0

Compensation enabled 1

*[CL-] NaCl conc. Concentration in g/kg water:

range 0.1 to 99.9 g/kg

Valid when code
04 is 1

05-09 Not used

3.75 μA for 50 micron type

7.50 μA for 25 micron type

T0502.EPS

(*1): Membrane check can be enabled when galvanic sensor is selected and cannot be used unless the

floating ball holder, PB350G or PB360G, is used.

(*2): The instrument will not perform salinity compensation simply by setting the salinity compensation to The instrument will not perform salinity compensation simply by setting the salinity compensation toThe instrument will not perform salinity compensation simply by setting the salinity compensation to

“1” (enabled) in Code 04, but requires the NaCl concentration. For measurement in consideration of
the salinity of a sample, first, manually calibrate with values corrected for salinity and enter the NaCl
concentration in Code 04. (See Section 6-4, “Calibration method using manual calibration method”)

IM 12J05D02-01E

IM 12J05D02-01E

5-16 Parameter setting

5-3-2. Temperature functions

Code 10 *T.SENS Select temperature sensor to suit the measuring probe. Refer to instructions

with DO sensor for which temperature sensor is used.
Code 11 *T.UNIT Select °C or °F for temperature display.
Code 12 *T.ADJ Adjust offset in temperature measurement when the sensor is at a stable

known value.
Code 13 *T.MAN Enable and set manual temperature compensation.

After the manual temperature set menu has been displayed, enter

temperature signals and press the [ENT] key to set. If the manual temperature

compensation is enabled, the temperature set menu is displayed in

maintenance mode.
The maximum and minimum slope values that may be entered depend on the nominal current from serv-

ice code 01.
Example : When nominal current = 3.75 µA the maximum and minimum slope calibration values

that may be entered are: Maximum 3.75 x 2 = 7.5 µA

Minimum 3.75 x 0.4 = 1.5 µA

5-3-3. Calibration functions

Code 20 *∆T.SEC Set stability parameters for calibration. A greater time, and/or a smaller step

gives

*∆mg/l greater stability before a calibration can be accepted. Use caution, however, to

avoid very long calibration times.
Code 21 *0.CAL Not normally necessary, zero calibration can be enabled when required.
Code 22 *ZERO Zero current values can be entered manually. If a zero calibration is made in

maintenance mode, a zero current value will be automatically reset.
NOTE:
A zero current value is displayed only when a zero calibration is enabled in

code 21.
*SLOPE Slope values can be manually entered with current values. If a span calibration

is made in maintenance mode, slope values will be automatically reset.
NOTE:
Slope values can be displayed with current values. When span check functions

are enabled in code 02, the above current values are converted to % values

and compared with the set values.
Slope % = current sensitive current /reference sensitive current

Parameter setting 5-17

Code Display Function Function detail X y Z Default values
Temperature Measuring Functions

10 *T.SENS Temp. Comp. Pt100 RTD 0

Pt1000 RTD (DO30) 1 1
PB36 = 2k2 NTC 2
22k NTC (SM31) 3

11 *T.UNIT Temp units Celsius 0 0

Fahrenheit 1
12 *T.ADJ Temp adjust Adjustment +/- 7.5 °C or +/- 13.5 °F
13 *T.MAN Manual TC Automatic temperature comp 0 0

Manual temp compensation 1 25 °C/ 77 °F
14-19 Not used

Code Display Function Function detail X y Z Default values
Calibration Settings

20 *∆T.SEC

*∆mg/l

21 *0.CAL Zero cal. Zero calibration disabled 0 0

22 *ZERO Zero entry Galvanic:

*SLOPE Slope entry Minimum setting

23-29 Not used

Stabilization
Step

Stabilisation time range 10- 600 s 60 s

DO step change range 0-50 mg/l

or 0-300 %

Zero Calibration enabled 1

In case that zero check is activated in code 02

within *I.CELL value set in code 02

In case that zero check is not activated in code

02 ±19.99 µA

Polarographic:

In case that zero check is activated in code 02

within *I.CELL value set in code 02

In case that zero check is not activated in code

02 ±199.9 nA

(*I.CELL set in code 01)

× (*SL.MIN set in code 02)

Maximum setting

(*I.CELL set in code 01)

× (*SL.MAX set in code 02)

0.05 mg/l

00.00 µA

000.0 nA

3.75 µA (50 nA)

IM 12J05D02-01E

IM 12J05D02-01E

5-18 Parameter setting

5-3-4. mA output settings

Code 30 *mA Select 0-20 mA or 4-20 mA for each of the mA outputs.
Code 31 *OUTP.F Select the parameter to be transmitted on each of the mA outputs.
*D/R Select the control action when PI selected on mA2. Direct action gives an

increasing output with an increase in measured value.
Code 32 *BURN Select “burn-out” signalling of diagnosed failures.
Code 33 *RGmA2 Set proportional band for PI control on mA2.
Code 34 *tImA2 Set integral time for PI control on mA2.
Code 35-36 *TABL1, Set up output linearization tables when selected in code 31.

*TABL2
Code 37 *DAMP Set damping time to smooth out erratic process fluctuations.
Code 38 *SWTCH After enabling range 1B, the user can set this range in commissioning mode.

By pressing the external button with range 1B enabled, range 1B will be used

instead of the normal range 1, until this button is not pressed anymore.

Parameter setting 5-19

Code Display Function Function detail X y Z Default values
mA Output Functions

30 *mA mA output Output 1 is 0- 20 mA 0 1.1
Output 1 is 4- 20 mA 1
Output 2 is 0- 20 mA 0
Output 2 is 4-20 mA 1
31 *OUTP.F Output function Process value on mA1 0 0.2
Table on mA1 1
Process value on mA2 0
Table on mA2 1
Temperature on mA2 2
PI control on mA2 3
*D/R Control action Reverse acting PI-control 0 0
Direct acting PI control 1
32 *BURN Burn-out No burn-out function on mA1 0 0.0
Burn low on fail on mA1 1
Burn high on fail on mA1 2
No burn out function on mA2 0
Burn low on fail on mA2 1
Burn high on fail on mA2 2
33 *RGmA2 Prop. range Proportional band: 0- 50 mg/l 5.0 mg/l
0-300 % saturation
34 *tImA2 Integral time Integral time in seconds 10 - 1999 s 100 s
35 *TABL1 Table for mA1 21 point table: Process value at
0, 5, .. 100 % of span none
36 *TABL2 Table for mA2 21 point table: 0, 5, .. 100 % none
37 *DAMP Output damping damping 0- 120 s 0 s
38 *SWTCH Range 1B Disabled 0 0
Enabled 1
39 Not used

Note
To enable wash function, set Service Code 38 to 0, Service Code 42 to 4.0.0, and Service Code

51 to 0.1.0.

IM 12J05D02-01E

IM 12J05D02-01E

5-20 Parameter setting

5-3-5. Contact outputs

Code 40, *S1 & *S2 Process relays can be set for a variety of alarm and control function.
41, 42 & 43
Digit “X” sets the type of trigger:
Off means that the relay is not active
Low setpoint means that the relay is triggered by a decreasing measurement.
High setpoint means that the relay is triggered by an increasing measurement

“HOLD” active means that there is maintenance activity in progress so the

measurement is not live.
For *S3 There is the extra possibility to set up for a wash controller.
For *S4 There is the extra possibility to set up for “FAIL” indication.

Digit “Y” sets the control action:
Process alarm is a simple On/Off trip controlled by the high/low setpoint.
Proportional duty cycle control has a pulse width modulation for proportional

dosing with solenoid valves.
Proportional frequency control is used for controlling electrically positioned

valves.
Temperature alarm is an On/Off trip on the measured temperature.

Digit “Z” sets the control parameter:
With or without “integral” action.

Parameter setting 5-21

Code Display Function Function detail X y Z Default values
Contact Settings

40 *S 1 Contact S1 Contact 1 inactive 0 2.0.0
Low alarm configuration 1
High alarm configuration 2
Active during HOLD 3
Activation by process value 0
Proportional duty cycle 1
Proportional pulse frequency 2
Activation by temperature 3
PI control inactive 0
PI control active 1
41 * S 2 Contact S2 Contact 2 inactive 0 1.0.0
Low alarm configuration 1
High alarm configuration 2
Active during HOLD 3
Activation by process value 0
Proportional duty cycle 1
Proportional pulse frequency 2
Activation by temperature 3
PI control inactive 0
PI control active 1
42 *S 3 Contact S3 Contact 3 inactive 0 4.0.0
Low alarm configuration 1
High alarm configuration 2
Active during HOLD 3
Active during WASH 4
Activation by process value 0
Proportional duty cycle 1
Proportional pulse frequency 2
Activation by temperature 3
PI control inactive 0
PI control active 1
43 *S 4 Contact S4 Contact 4 inactive 0 4.0.0
Low alarm configuration 1
High alarm configuration 2
Active during HOLD 3
Active during FAIL 4
Activation by process value 0
Proportional duty cycle 1
Proportional pulse frequency 2
Activation by temperature 3
PI control inactive 0
PI control active 1

IM 12J05D02-01E

IM 12J05D02-01E

5-22 Parameter setting

Code 44 *D.TIME The delay time (or dead time) sets the minimum relay switching time. This

function can be adjusted to give a good alarm function in a noisy process,

preventing the relay from “chattering” or repeatedly switching when the signal

is close to the setpoint.
*P.HYST The hysteresis is the value beyond the setpoint that the measured value

*T.HYST must exceed before the control function will start working.
Code 45 *RANGE Proportional range is the value above (or below) the setpoint that generates full

output in proportional control.
*PER. The time period of the overall pulse control cycle (one ON and one OFF

period).
*FREQ. The maximum frequency for the pulse frequency control.

Code 46 *tI.CNT The integral time for the PI control settings.
Code 47 *EXPIR When a system is set up to control on the relay outputs, the expiry time can be

enabled to warn of an ineffective control. In other words, when the setpoint is

exceeded for more than 15 minutes an error message is generated. This can

mean, for example, that the reagent tank is empty.

Parameter setting 5-23

Code Display Function Function detail X y Z Default values
Contacts Settings

44 *D.TIME Dead Time Delay after setpoint passed 0- 2.0 s 0.2 s
*P.HYST Hysteresis Process value hysteresis
0-50 mg/l or 0-300 % 0.1 mg/l
*T.HYST Temp hyst Temperature hysteresis
0- 5 °C (0- 12 °F) 0.5 °C
45 *RANGE Prop. control Proportional range 0- 50 mg/l 5.0 mg/l
*PER. Duty cycle Period/ Duty cycle : 5- 100 s 10.0 s
*FREQ. Frequency Frequency control 50 - 120 per min. 70 p.m.
46 *tI.CNT Integral time Int. time for contacts 10 - 1999 s 100 s
47 *EXPIR Time out alarm Disable time out alarm 0 0
Enable time out alarm 1
*tE. mn time out alarm after 0.5 - 199.9 min 15 min
48-49 Not used

IM 12J05D02-01E

IM 12J05D02-01E

5-24 Parameter setting

5-3-6. User interface

Code 50 *RET When Auto return is enabled, the converter reverts to the measuring mode

from anywhere in the configuration menus, when no button is pressed during
the set time interval of 10 minutes.

Code 51 *MODE The adjustment of the contact setpoints, and the manual operation of the

wash system can be setup for operation in the maintenance mode. (Through
the closed front cover). In maintenance mode the pressure can be entered
(M. PRESS). If manual pressure is enabled, a warning is given when starting
manual-, water and air calibration.

Code 52 *PASS Passcodes can be set on any or all of the access levels, to restrict access to

the instrument configuration.
Code 53 *Err.04
Hard fail gives a steady FAIL flag in the display, and a continuous contact

Soft fail gives a flashing FAIL flag in the display, and the relay contacts are

Code 54 *E12 Overrange alarm, set limit for supersaturation permissible before FAIL alarm is

Code 55 *CALL.M Call for maintenance is a contact trigger to signal that the system has been in

Code 56 *UNIT Select mg/l, ppm or % saturation as the main unit, to suit the application.

Error message configuration. Two different types of failure mode can be set.

closure. All the other contacts (controls) are inhibited (except HOLD contacts),

and a Fail signal is transmitted on the outputs when enabled in code 32.

pulsed. The other contacts (controls) are still functional, and the controller

continues to work normally. The call for maintenance is a good example of

where a SOFT fail is useful. A warning that the regular maintenance is due,

should not be used to shut down the whole measurement. An extra choice is

added for Errors set to Soft Fail. It can be set to LCD + Fail contact (current

situation) or to LCD only.

triggered.

service for longer than the set time without calibration. The user can set up to

250 days as a routine service interval.

Parameter setting 5-25

Code Display Function Function detail X y Z Default values
User Interface

50 *RET Auto return No return to meas. from HOLD 0 1
Return to meas after 10 min 1
51 *MODE add. to MAINT Setpoint adj. disabled 0 0.0.0
Setpoint adj. also in MAINT 1
Wash start disabled 0
Wash start in maintenance mode 1
Manual pressure disabled 0
Manual pressure enabled 1
52 *PASS Password Direct access to MAINT 0 0.0.0
MAINT protected by password #
Direct access to COMM 0
COMM protected by password #
Direct access to SERV 0
SERV protected by password #

Pass: 111 for #=1,
333 for #=2,
777 for #=3,
888 for #=4,
123 for #=5,
957 for #=6,
331 for #=7,
546 for #=8,
847 for #=9

53 *Err.01 Error setting Response & Time failure Soft fail 0

Zero calibration Hard fail 1 1 Hard
*Err.03 Slope calibration Soft fail 0
Slope calibration Hard fail 1 1 Hard
*Err.04 Membrane failure Soft fail 0
Membrane failure Hard fail 1 1 Hard
*Err.07 Temperature sensor open Soft fail 0
Temperature sensor open Hard fail 1 1 Hard
*Err.08 Temp. sensor shorted Soft fail 0
Temp. sensor shorted Hard fail 1 1 Hard
*Err.09 Cell current abnormal Soft fail 0
Cell current abnormal Hard fail 1 1 Hard
*Err.12 Abnormal measured value Soft fail 0
Abnormal measured value Hard fail 1 1 Hard
*Err.16 Cell for maintenance Soft fail 0
interval time exceeded
Cell for maintenance Hard fail 1 1 Hard
interval time exceeded
*Err.22 Control time-out Soft fail 0 0 Soft
Control time-out Hard fail 1
*SOFT LCD Fail Constant 0 0 LCD Fail
LCD only 1

54 *E12 overrange limit E12 active at 0 - 300 % sat (Note) 150%
55 *CALL.M E16 setting No call for maintenance 0 0
Call for maint. enabled 1
E16 message after 1- 250 days 30
56 *UNIT PV unit Unit of measurement mg/l 0 0
Unit of measurement ppm 1
Unit of measurement % sat. 2
57-59 Not used

*Err.02 Zero calibration Soft fail 0

Response & Time failure Hard fail 1 1 Hard

Note: For setting a value greater than 199.9, move the decimal point. For a value greater than 200%,

decimal places cannot be used.

IM 12J05D02-01E

IM 12J05D02-01E

5-26 Parameter setting

5-3-7. Communication setup

Code 60 *COMM. The settings should be adjusted to suit the communicating device connected to

the RS485 port.
*SET.
*ADDR.
For the Yokogawa PC402 software package, the default settings match the

software as shipped.
Code 61 *HOUR The clock/calendar for the logbook is set for current date and time as

reference.
*MINUT
*SECND
*YEAR
*MONTH
*DAY

Code 62 *ERASE Erase logbook function to clear the recorded data for a fresh start. This may

be desirable when re-commissioning an instrument that has been out of service

for a while.

5-3-8. General

Code 70 *LOAD The load defaults code allows the instrument to be returned to the default set

up with a single operation. This can be useful when wanting to change from

one application to another.

5-3-9. Test and setup mode

Code 80 *TEST Not used
Note:

Attempting to change data in service code 80 and above without the proper instructions and

equipment, can result in corruption of the instrument setup, and will impair the performance of the
unit.

Parameter setting 5-27

Code Display Function Function detail X y Z Default values
Communication

60 *COMM. Communication Set communication Off 0 0.1 Off
Set communication On 1
Communication write enable 0 write
Communication write protect 1 protect
*SET. Baud rate & parity Baud rate 1200 0 3.1
2400 1
4800 2
9600 3 9600
Parity Off 0
Odd 1 Odd
Even 2
*ADDR. Network address Set address 00 to 15 00
61 *HOUR Clock setup Adjust to current date and time using
*MINUT >, ^ and ENT keys
*SECND
*YEAR
*MONTH
*DAY
62 *ERASE Erase logbook Press YES to clear logbook data
63-69 Not used

Code Display Function Function detail X y Z Default values
General

70 *LOAD Load defaults Reset configuration to default values
71-79 Not used

Code Display Function Function detail X y Z Default values
Test and setup mode

80 *TEST Test and setup Not used

IM 12J05D02-01E

Calibration 6-1

6. CALIBRATION PROCEDURE

Calibration of the dissolved oxygen analyzer is performed in the following situations:

• When a new dissolved oxygen sensor is installed.

• When the membrane is replaced and/or the electrolyte solution is replaced

• When the sensor has been disassembled and reassembled for maintenance

• When the measuring error after cleaning exceeds the acceptable deviation from reference method

• When error message E12 or E16 indicates the need for maintenance

6-1. General

6-1-1. Calibration methods

There are three methods for calibration of the EXA dissolved-oxygen analyzer: air calibration, water cali­bration and manual calibration.

Air calibration

This is the most common and easiest way to calibrate the analyzing system. The calibration is done in

AIR.CAL mode in maintenance level.

Water calibration

This is the traditional way to calibrate dissolved oxygen analyzers in laboratory environment. . Accurate
results can be obtained if the calibration is performed carefully. The water calibration may include a zero
calibration if so selected in service code 21. Normally only a zero check is performed without calibration,
since a good sensor has no zero signal.
Water calibration is not possible in salt water unless salinity compensation is activated in service code

04. The calibration is done in H2O.CAL mode in maintenance level.
NOTE:

In normal industrial environment better results are obtained with air calibration, which is therefore

the recommended method.

Manual calibration

This is a calibration method whereby the sensor is not exposed to a calibration fluid, but is calibrated
by comparison with a reference method. This reference method is normally a laboratory analysis of the
water sample: either by iodometric titration according ISO 5813 or an electrochemical method according
ISO 5814.
The calibration is done in MAN.CAL mode in maintenance level.

IM 12J05D02-01E

6-2 Calibration

6-1-2. Diagnostic functions performed during calibration

The calibration is a semi-automatic calibration, which means that the sensor output is used for calcula­tion of sensor parameters after the readings have stabilized. The criteria for stabilization are set in serv­ice code 20. If stable readings are not achieved within one hour error E1 message will appear on the
display and the procedure is aborted. The calculated sensor parameters are compared with preset toler­ances and if these conditions are not met, Error E2 (Zero Error) or E3 (Slope Error) will be signalled.

Notes: 1. Error messages that appear initially indicate inadequate settings of the diagnostic variables in

service codes 01, 20 and/or 22.

2. Patience improves the accuracy of calibration. When the EXA prompts the user that the

preset criteria are met by showing CAL.END message it only means that the minimum criteria
are met. When the signal still changes after this initial acceptance, EXA will automatically
update the sensor characteristics with the new information.

6-2. Calibration procedure using air calibration method

6-2-1. Preparation

Move the sensor to a maintenance site and wash off any dirt on the membrane. Lightly wipe off any
remaining water from the membrane with a soft tissue.
Expose the sensor to the air in an environment where there is no temperature change and no wind. ( A
convenient way to accomplish this environment is to place the sensor in an empty bucket)

Note: If sensors are used without temperature compensating element, the temperature must be adjusted

to ambient temperature in service code 13.

IM 12J05D02-01E

6-2-2. Procedure for air calibration

NO

YES

MEASURE

MAN.CAL
DISPLAY
HOLD

NO MODEYES

ENT

YOKOGAWA

MODE

AIR.CAL

CONTACTS

S1

S2

WASH/S3

FAIL/S4

H2O.CAL

NO

YES

YES

Press YES for single point
adjustment.

Press the MODE key. AUT.CAL appears in the display, and the

YES/NO key prompt flags flash. Press YES.

YES NO

YES

NO

YES NO

YES

YES

The instruments waits for
the reading to stabilize.
(The display flashes)
When reading Is stable,
the CAL.END message
appears.

Note:To start calibration

with a zero solution,
press NO (zero
calibration must be
activated in service
code 21).

Transfer to zero
solution and press YES.

When the reading is stable, the CAL.END
message appears. Press YES.

After briefly displaying WAIT, the display returns to
the normal readout.

After briefly displaying WAIT, the display

returns to the normal readout.

If “X.X.1” is selected in Service Code 51,
the M.PR.ON message will appear to
indicate that the manual pressure is
enabled. Press YES to proceed.

YES

YES

from *2

to *1

NO

NO

from *1

NO

NO

to *2

to *2

to *2

to *2

NO

NO

YES

NO

Calibration 6-3

IM 12J05D02-01E

6-4 Calibration

6-3. Calibration procedure using water calibration method

6-3-1. Preparation

Move the sensor to a maintenance site and wash off any dirt on the membrane. Lightly wipe off any
remaining water from the membrane with a soft tissue.

Prepare the necessary equipment and reagents to be used for the span and (if required) zero calibration.
Equipment for span calibration includes:

• beaker or bucket

• magnetic stirrer or other means of agitating the water

• Demineralized water or salty process water if salinity compensation is activated

• Air supply pump (aquarium pump)

• Glass diffuser to generate small air bubbles
NOTE:

It takes 15 to 30 minutes of aeration before it can be assumed that the water is fully saturated with air.
Reagent for zero calibration:

• Sodium sulfite

• demineralized water
The zero oxygen solution contains 20- 30 grams of sodium sulfite per liter.

6-3-2. Calibration operation (water calibration method)

If both zero and span calibration are used, it is better to start with span calibration in spite of normal
calibration sequence with analog instrumentation. Otherwise the sensor must be rinsed off carefully to
prevent ingress of oxygen absorbing sulfite in the aerated water.

NOTE:
Zero calibration in the sodium sulfite solution takes a long time. Even after CAL.END prompt it

is necessary to wait 40-50 minutes before zero adjustment can be made. Otherwise calibration
errors are introduced in the measurement. It is recommended not to do a zero calibration, but a
zero check only. A good clean sensor does not have a zero current and does not require zero
calibration. If the sensor has a substantial zero current, the sensor has to be disassembled,
cleaned and filled with fresh electrolyte solution and new membrane has to be fitted.

Calibration may take longer than 10 minutes. Before starting the calibration procedure, check the

setting of Auto Return (*RET.) in Service Code 50. It is recommended to set the Auto Return to “0”
(No return to meas. from HOLD). After the calibration procedure has been completed, set the Auto
Return to the desired setting in Service Code 50.

IM 12J05D02-01E

6-3-3. Procedure for Water calibration

YES NO

YES

NO

YES NO

YES

The instruments waits for
the reading to stabilize.
(The display flashes)
When reading Is stable,
the CAL.END message
appears.

NO

YES

NO

YES

YES

NO

YES

MEASURE

MAN.CAL
DISPLAY
HOLD

NO MODEYES

ENT

YOKOGAWA

MODE

AIR.CAL

CONTACTS

S1

S2

WASH/S3

FAIL/S4

H2O.CAL

NO

YES

YES

Place sensor
in calibration
solution

Press YES for single point
adjustment.

Note: To start calibration
with a zero solution,
press NO (zero
calibration must be
activated in service
code 21).

Transfer to zero
solution and press YES.

When the reading is stable, the CAL END
message appears. Press YES.

After briefly displaying WAIT, the display returns to
the normal readout.

After briefly displaying WAIT, the display

returns to the normal readout.

NO

to *2

to *2

from *2

to *1

from *1

NO

NO

NO

NO

If “X.X.1” is selected in Service
Code 51,
the M.PR.ON message will appear
to indicate that the manual
pressure is enabled. Press YES to
proceed.

NO

YES

to *2

to *2

NO

Calibration 6-5

IM 12J05D02-01E

6-6 Calibration

6-4. Calibration method using manual calibration method

6-4-1. Preparation

a. Cleaning

Confirm that the readings of the analyzer are stable and measured with a clean sensor.
Otherwise move the sensor to a maintenance site and wash off any dirt on the sensor membrane

Move the sensor back to the process water and wait for the readings to stabilize.

b. Sampling

The manual calibration procedure involves adjustment of the readings to a reference standard.
Normally this reference is a laboratory measurement that analyses a sample that must be identical to

the sample measured with the on-line analyzer.

The following precautions must be taken into account:

• The sample must be analyzed directly after sampling to avoid change of dissolved oxygen
concentration or temperature after sampling.

• The reference standard must be analyzed with a laboratory meter that is calibrated prior to
sample analysis.

• The reference method must be calibrated with the same calibration data as specified in ISO
5814 to avoid in discrepancies.

Most important calibration data are:
Dissolved oxygen concentration at saturation conditions as function of temperature, barometric pres-

sure, altitude and salinity.

These data are included in this manual for reference and verification of correct calibration of refer-

ence analyzers. DO402G has taken all these variables into account during the semi-automatic cali­bration methods.

c. Compensating the salinity of a sample.
Example of procedure for (salinity compensation) calibration.

When performed in consideration of the salinity, calibration should be done manually.
The following shows a procedure for salinity compensation. Perform the calibration referring to Table

6.1.

Assuming that the atmosphere is 1 atm, the solution temperature is 22.5 ºC, and the salinity is 30 g/
kg (3 wt % seawater equivalent):

1. Calculating the saturated concentration of water

According to Table 6.1, the solubility is 8.74 mg/l at 22 ºC and 8.58 mg/l at 23 ºC.
The solubility at 22.5 ºC is calculated as follows:

8.74 + (8.58 - 8.74) × (22.5 - 22) = 8.66 mg/l

2. Calculating the value corrected for salinity

0.0453 + (0.0443 - 0.0453) × (22.5 - 22) = 0.0448 mg/l

0.0448 × 30 = 1.34 mg/l

3. Calculating the saturated concentration of solution (to be calibrated)

8.66 – 1.34 = 7.32 mg/l

NOTE:
When salinity compensation is done, salinity compensation must be enabled in Service Code 04

to allow the instrument to show the saturated concentration (%) during sample measurements
correctly.

IM 12J05D02-01E

NO

YES

ENT

NO

YES

NO

YES

YES

ENT

ENT

ENT

YES

NO

NO

MEASURE

MAN.CAL
DISPLAY
HOLD

NO MODEYES

ENT

MODE

AIR.CAL

CONTACTS

S1

S2

WASH/S3

FAIL/S4

H2O.CAL

NO

YES

NO

After briefly displaying WAIT,

the display returns to

the normal readout.

Press YES to return to the

measuring mode. (Single Point

adjustment only)

Select the flashing digit with the

> key.

Increase its value by pressing the

^

key.

When the correct value is displayed, press ENT to enter the change.

YOKOGAWA

YES

YES

NO

NO

If “X.X.1” is selected in Service Code
51, the M.PR.ON message will appear
to indicate that manual pressure is
enabled. Press YES to proceed.

6-4-2. Procedure for manual calibration

Calibration 6-7

IM 12J05D02-01E

6-8 Calibration

Table 6-1. Solubility of oxygen (mg/l) in water as a function of temperature & salinity

Temp Solubility of oxygen in water in equilibrium Correction to be substracted for each degree of salinity
with air expressed in grams per kilogram of total salts in water
@101.325kPa[pO
°C mg/l mg/l

0 14.62 0.0875
1 14.22 0.0843
2 13.83 0.0818
3 13.46 0.0789
4 13.11 0.0760
5 12.77 0.0739
6 12.45 0.0714
7 12.14 0.0693
8 11.84 0.0671
9 11.56 0.0650
10 11.29 0.0632
11 11.03 0.0614
12 10.78 0.0593
13 10.54 0.0582
14 10.31 0.0561
15 10.08 0.0545
16 9.87 0.0532
17 9.66 0.0514
18 9.47 0.0500
19 9.28 0.0489
20 9.09 0.0475
21 8.91 0.0464
22 8.74 0.0453
23 8.58 0.0443
24 8.42 0.0432
25 8.26 0.0421
26 8.11 0.0407
27 7.97 0.0400
28 7.83 0.0389
29 7.69 0.0382
30 7.56 0.0371

] [∆pO

2

]

2

Table 6-2. Solubility of oxygen (mg/l) at various

temperatures and elevations (based on sea level
barometric pressure of
760 mm Hg)

Temp Elevation (metres above sea level)
°C 0 300 600 900 1200 1500 1800

0 14.6 14.1 13.6 13.2 12.7 12.3 11.8
2 13.8 13.3 12.9 12.4 12.0 11.6 11.2
4 13.1 12.7 12.2 11.9 11.4 11.0 10.6
6 12.4 12.0 11.6 11.2 10.8 10.4 10.1
8 11.8 11.4 11.0 10.6 10.3 9.9 9.6
10 11.3 10.9 10.5 10.2 9.8 9.5 9.2
12 10.8 10.4 10.1 9.7 9.4 9.1 8.8
14 10.3 9.9 9.6 9.3 9.0 8.7 8.3
16 9.9 9.5 9.2 8.9 8.6 8.3 8.0
18 9.5 9.2 8.9 8.6 8.3 8.0 7.7
20 9.1 8.8 8.5 8.2 7.9 7.7 7.4
22 8.7 8.4 8.1 7.8 7.6 7.3 7.1
24 8.4 8.1 7.8 7.6 7.3 7.1 6.8
26 8.1 7.8 7.6 7.3 7.0 6.8 6.6
28 7.8 7.5 7.3 7.0 6.8 6.6 6.3
30 7.5 7.2 7.0 6.8 6.5 6.3 6.1
32 7.3 7.1 6.8 6.6 6.4 6.1 5.9
34 7.1 6.9 6.6 6.4 6.2 6.0 5.8
36 6.8 6.6 6.3 6.1 5.9 5.7 5.5
38 6.6 6.4 6.2 5.9 5.7 5.6 5.4
40 6.4 6.2 6.0 5.8 5.6 5.4 5.2

Table 6-3. Solubility of oxygen (mg/l) of sea

water & fresh water (based on sea
level barometric pressure of 760 mm
Hg)

Temp Solubility
Seawater Fresh water
°C mg/l mg/l

0 11.97 14.62
2 11.36 13.84
4 10.82 13.13
6 10.29 12.48
8 9.84 11.87
10 9.43 11.33
12 9.05 10.83
14 8.69 10.37
16 8.37 9.95
18 8.06 9.54
20 7.77 9.17
22 1.48 8.83
24 7.21 8.53
26 6.93 8.22
28 6.67 7.92
30 6.41 7.63

IM 12J05D02-01E

Maintenance 7-1

7. MAINTENANCE

It is important for maintaining the measurement accuracy of the EXA DO series of wire dissolvedoxygen
metering system to perform inspection and maintenance at fixed intervals. It also serves to prevent prob­lems from arising.
This chapter describes daily inspection and maintenance for the purpose of maintaining system perform­ance.

7-1. Overall dissolvedoxygen metering system

Tables 7-1 and 7-2 show the inspection and maintenance items for equipment composing 4-wire dis­solved-oxygen metering system. The procedure of inspection and maintenance for the dissolvedoxygen
converter is described in Section 7-2. For inspection and maintenance of the sensors and holders, see
each instruction manual respectively.

7-1-1. Inspection and maintenance to be implemented periodically

Table 7-1 shows the items which are recommended to be inspected and maintained periodically.

Table 7-1. Items for periodic inspection and maintenance of 4-wire dissolved-oxygen metering system

Instrument or apparatus Item Recommended Interval

All equipment a. Calibration a. 1 to 2 months
Dissolvedoxygen sensor a. Cleaning of membrane a. 1 to 2 months
b. Polishing of silver electrode b. 6 to 8 months

surface and replacement of electrolyte
c. Replacement of membrane assembly c. 6 to 8 months
Dissolved-oxygen converter a. Inspection of temperature indication a. 6 months

(error check)
b. Replacement of fuse b. 1 to 2 years
Float holder a. Sweeping of winch mechanism a. (depends on installation

environment)
Immersion holder a. Inspection of sensor holding O-ring a. 6 months
b. Sweeping of cleaner nozzle b. 1 to 2 months
c. Inspection for leakage from the solenoid c. 6 months

valve for cleaning utility

7-1-2. Inspection and maintenance to be implemented on occasion

Occasionally implement the maintenance that is not directly related to measurement functions and main­tenance associated with errors.

Table 7-2. Items for occasional inspection and maintenance of 4-wire dissolved-oxygen metering

Faulty phenomenon System content of inspection

Error E2 occurrence Check whether the dissolved-oxygen sensor membrane is

contaminated or not.
Check whether the nozzle is clogged or not.
Error E3 occurrence Polish the silver electrode surface of the dissolved-oxygen sensor

and replace the electrolyte.
It is difficult to see the inside Wipe off the dirt on the transparent window using tissue paper or
of the converter through the the like. (Use detergent for hard-to-clean dirt.)
window

IM 12J05D02-01E

IM 12J05D02-01E

7-2 maintenance

DANGER

7-2. Periodic maintenance for the EXA DO402G converter

The DO402G converter requires very little periodic maintenance. The housing is sealed to IP65 (NEMA
4X) standards, and remains closed in normal operation. Users are required only to make sure the front
window is kept clean in order to permit a clear view of the display and allow proper operation of the
pushbuttons. If the window becomes soiled, clean it using a soft damp cloth or soft tissue. To deal with
more stubborn stains, a neutral detergent may be used.

NOTE:
Never used harsh chemicals or solvents. In the event that the window becomes heavily stained or

scratched, refer to the parts list (Chapter 9) for replacement part numbers.

When you must open the front cover and/or glands, make sure that the seals are clean and correctly fit­ted when the unit is reassembled in order to maintain the housing’s weatherproof integrity against water
and water vapor. The DO measurement uses small signal currents and may otherwise be prone to prob­lems caused by exposure of the circuitry to condensation.

7-3. Fuse Replacement

This section describes how to replace the power supply fuse.

• Use only a fuse of the specified current, voltage and type ratings to prevent fire.

• Power to the instrument must be turned off at the external breaker before replacing the fuse. After
replacing the fuse, install a high-voltage shield plate before turning the power on.

• Do not short circuit the fuse holder.

Specified Ratings of the Power Supply Fuse

The power supply fuse (recommended fuse) used in the DO402G is as follows.

• 100/115 V AC version
Maximum rated voltage: 250 V
Maximum rated current: 200 mA
Compliance: UL, CSA, VDE, Japan’s Electrical Appliance and material Safety Law
Part number: A1105EF

• 230 V AC version
Maximum rated voltage: 250 V
Maximum rated current: 100 mA
Compliance: UL, CSA, VDE, Japan’s Electrical Appliance and material Safety Law
Part number: A1103EF

How to replace the fuse

Shield Plate

Fuse Cover

Fuse Holder

1) Before replacing the fuse, turn off power to the instrument at the external breaker.

2) Remove the instrument cover and the high-voltage shield plate.

3) Remove the cover from the fuse holder by pulling out by hand.

4) Remove the fuse and install a new, recommended or equivalent fuse on the holder.

5) Put the fuse cover back on the holder securely.

6) Install the high-voltage shield plate.
It is recommended that the fuse be replaced every two years even if it has not blown.

Figure 7-1. How to replace the fuse

Maintenance 7-3

IM 12J05D02-01E

Troubleshooting 8-1

8. TROUBLESHOOTING

This chapter describes the countermeasures for failures, classifying the cases into three categories:
dissolvedoxygen converter failure, detection of failure with the self-diagnosis function, and abnormal
measured values. The causes for abnormal measured values are not limited to equipment failures. if an
abnormal phenomenon occurs, first check the following items:

• Is the property of the measuring solution different from normal ?

• Is the dissolvedoxygen sensor properly installed?

8-1. Measures in the case of converter operation failure

8-1-1. No dissolved-oxygen converter operation

If the converter does not operate even when the power is supplied, one cause may be a blown fuse
inside the converter.
Examine the fuse by turning off the power supply (see Subsection 3-3-1 on page 3-5).
If the fuse is blown, replace it with a new one. If fuses frequently blow and the cause is not clear, request
an inspection by Yokogawa.
If the fuse is normal, examine the wiring system.

8-1-2. Operation key or display failure

If the operation keys do not operate smoothly or the display fails (e.g., a missing character segment),
repair of the printed circuit board (digital board) (replacement with a new one) is required.
After the printed circuit board is replaced, operation checks and parameter settings are necessary.
Contact Yokogawa and request board-replacement work.

IM 12J05D02-01E

IM 12J05D02-01E

8-2 Troubleshooting

8-2. Measures in the case of failure (Error) detection

If a failure is detected through the self-diagnosis of the DO402G dissolvedoxygen converter, the FAIL
contact is closed. The FAIL lamp on the operation panel lights up and an error number appears in the
data display.

Note:
If an error is detected during configuration, the FAIL contact signal is output immediately but the

error number is displayed after that action or operation is completed.

When a FAIL contact signal is output, take measures according to Table 8-1.

Table 8-1. Measures in the case of failure (Error) detection

Error

Generation Mode Error Content and Causes Measures

No.

E 1 AIR.CAL mode

H2O. CAL mode

E 2 H2O. CAL mode Zero point error failure

E 3 AIR.CAL mode

H2O. CAL mode
MAN.CAL mode

E 4 Measuring mode Sensor membrane failure Replace membrane

E 7 All modes Measured temperature failure (too high)

E 8 All modes Measured temperature failure (too low)

E 9 All modes Input current failure

Stability failure
Even after an hour has elapsed, the measured value
change does not decrease within the set value of (mg/l)

• Sensor temperature changes.

• Dissolved-oxygen of the calibration solution changes.

• The value of A(mg/l) is not suitable.

The zero point error exceeds the set range

• Dirt sticks to the sensor membrane.

• Membrane abnormality. Electrolyte degradation.
Slope failure

The slope exceeds the range of 40 to 200 % of the
theoretical value.

• Dirt sticks to the sensor membrane.

• Membrane abnormality. Electrolyte degradation.

It exceeds 50.0 °C (122.0 °F).

• Measuring solution temperature is high

• CODE 10 setting is not correct

• Sensor cable wiring failure

• Temperature sensor has failed

It falls below 0 °C (or 32.0 °F).

• Measuring solution temperature is low

• CODE 10 setting is not correct

• Sensor cable wiring failure

• Temperature sensor has failed.

It does not satisfy the following equation:
input current < 50 µA for galvanic sensor
< 500 nA for polarographic sensor

Eliminate the causes and press the
(NO) key to perform re calibration.

Clean the sensor membrane and
recalibrate. If the error is detected
again, replace the electrolyte and the
membrane.

Clean the sensor membrane and
recalibrate. If the error is detected
again, replace the electrolyte and the
membrane.

Check for wet O-rings in the
membrane assembly or wet sealing
face.
Wipe off wet areas and dry out.

Examine the temperatures of the
measuring solution and sensor and the
CODE 10 setting
Examine the sensor cable connection
status.
If the temperature sensor fails
(abnormal resistance), replace the
sensor.

Examine the temperatures of the
measuring solution and sensor and the
CODE 10 setting.
Examine the sensor cable connection
status.
If the temperature sensor fails
(abnormal resistance), replace the
sensor.

Examine the setting for CODE 01, 02

Troubleshooting 8-3

Error Generation Error content and Causes Measures
No. Mode

E10 All modes EEPROM writing failure Turn off the power and then turn it
Electronic circuit failure back on and check whether or not the
system returns to normal.
If the failure occurs again, contact
Yokogawa to request repair.
E12 All modes Abnormal measured value Examine the setting for CODE 01, 02
The dissolved-oxygen value (%sat.) exceeds 10, 12 & 54.
150 % (or value set in code 54) Accurately perform calibration.
E15 CODE 12 Temperature error correction failure Accurately measure the temperature of
The difference between the corrected value the measuring solution (dissolved oxygen
and the standard value exceeds the range sensor).
corresponding to ±7.5°C (±13 5°F). Examine whether the sensor cable fails

• Temperature entry is not accurate. (partial disconnection or degraded

• Sensor cable failure insulation) and then correct the
temperature error again.
E16 All modes Call for maintenance-interval time exceeded Perform maintenance. Reset interval.
E17 RANGE mode Incorrect span. Change the maximum or minimum value
In the range setting, a value which makes in the range so that a span more than
the span less than 1.0mg/l (or ppm) or 10 the permissible value is obtained.
% sat. has been set.
E18 CODE 35 & 36 Table values make no sense. Reprogram.
E19 At data entry Configuration failure Re-enter a value within the permissible
A value not within the permissible range range.
is entered.
E20 All modes Instrument initialization failure Repair is necessary. Contact Yokogawa
to request repair.
E21 All modes EPROM comparison failure Repair if necessary. Contact Yokogawa
to request repair.
E22 All modes The time-out interval for high or low
alarm has elapsed. to use this function.
(if the function is enabled in CODE 47) Reset the error with the (NO) key or
(yES) key.

Take measures depending on the

purpose

NOTE:
It is possible that the error message does not disappear immediately after corrective measures.

Then turn power off and the turn it back on and check whether the system returns to normal.

IM 12J05D02-01E

9. SPARE PARTS

See Customer Maintenance Parts List.

Spare parts 9-1

IM 12J05D02-01E

10. APPENDIX

Adjustable limits and defaults for settings in Commissioning Level

10-1. Setpoint

Variable Default Lower limit Upper limit

*OX1 19.5 mg/l 0.0 mg/l 50.0 mg/l

0.0 ppm 50.0 ppm

0.0 %sat 300 %sat
*OX2 1.0 mg/l 0.0 mg/l 50.0 mg/l

0.0 ppm 50.0 ppm

0.0 %sat 300 %sat
*OX3 10.0 mg/l 0.0 mg/l 50.0 mg/l

0.0 ppm 50.0 ppm

0.0 %sat 300 %sat
*OX4 10.0 mg/l 0.0 mg/l 50.0 mg/l

0.0 ppm 50.0 ppm

0.0 %sat 300 %sat
*Sp.mA2 10.0 mg/l 0.0 mg/l 50.0 mg/l

0.0 ppm 50.0 ppm

0.0 %sat 300 %sat
* T1 25.0 ºC/77 ºF 0.0 ºC/32 ºF 50 ºC/122 ºF
* T2 25.0 ºC/77 ºF 0.0 ºC/32 ºF 50 ºC/122 ºF
* T3 25.0 ºC/77 ºF 0.0 ºC/32 ºF 50 ºC/122 ºF
* T4 25.0 ºC/77 ºF 0.0 ºC/32 ºF 50 ºC/122 ºF

Appendix 10-1

10-2. Range

Variable Default Lower limit Upper limit

Range 1: 0% = 0.00 0.0 mg/l 50.0 mg/l
Process 100% = 19.99 0.0 ppm 50.0 ppm

0.0 %sat 300 %sat
Range 2: 0% = 0.00 0.0 mg/l 50.0 mg/l
Process 100% = 19.99 0.0 ppm 50.0 ppm

0.0 %sat 300 %sat
Temperature 0% = 0 ºC / 32 ºF 0.0 ºC / 32 ºF 50 ºC / 122 ºF
100% = 50 ºC / 122 ºF

Note:
The range has a minimum span of: 1.0 mg/l, 1.0 ppm or 10 %sat.
In case of a temperature output 25 ºC or 50 ºF

10-3. Hold

Variable Default Lower limit Upper limit

mA fix 1 10.00 mA 0 or 4 mA 20 mA
mA fix 2 10.00 mA 0 or 4 mA 20 mA

10-4. Wash

Variable Default Lower limit Upper limit

Interval 6 hours 0.1 hours 36.0 hours
Wash time 0.5 minutes 0.1 minutes 10.0 minutes
Recovery time 0.5 minutes 0.1 minutes 10.0 minutes

IM 12J05D02-01E

IM 12J05D02-01E

10-2 Appendix

10-5. User setting table

FUNCTION SETTING DEFAULTS USER SETTINGS
Parameter specific functions

01 *S.TYPE 0 Galvanic (7 µA)
*I.CELL 0 3.75 µA
02 *CHECK 0.1.0 Zero Off
Slope On
Membrane Off
04 *SAL.TY 0 Off

Temperature measuring functions

10 *T.SENS 1 Pt1000
11 *T.UNIT 0 °C
12 *T.ADJ None
13 *T.MAN 0 Off

Calibration parameter functions

20 *∆T.SEC 60 sec.

*∆mg/l 0.05 mg/l

21 *0.CAL 0 Off
22 *ZERO 0 µA (nA)
*SLOPE 3.75 (50) µA (nA)

mA outputs

30 *mA 1.1 both 4-20mA
31 *OUTP.F 0.2 DO & Temp.
*D/R 0 Reverse (control)
32 *BURN 0.0 both off
33 *RG.mA2 5.0 mg/l only for PI control
34 *tI.mA2 100 sec only for PI control
35 *TABL1 21 pt table see code 31, §10-1
36 *TABL2 21 pt table see code 31, §10-1
37 *DAMP 0 sec.
38 *SWTCH 0 Off

Contacts

40 *S1 2.0.0 high process Al.
41 *S2 1.0.0 low process Al.
42 *S3 4.0.0 WASH
43 *S4 4.0.0 FAIL
44 *D.TIME 0.2 sec.
*P.HYST 0.1 mg/l
*T.HYST 0.5 °C
45 *RANGE 5.0 mg/l
*PER 10.0 sec.
*FREQ 70 p/min
46 *tI.CNT 100 sec. only for PI control
47 *EXPIR 0 off
*tE.min 15 min

FUNCTION SETTING DEFAULTS USER SETTINGS
User Interface

50 *RET 1 on
51 *MODE 0.0.0 all off
52 *PASS 0.0.0 all off
53 *Err.01 1 hard fail
*Err.02 1 hard fail
*Err.03 1 hard fail
*Err.04 1 hard fail
*Err.07 1 hard fail
*Err.08 1 hard fail
*Err.09 1 hard fail
*Err.12 1 hard fail
*Err.16 0 soft fail
*Err.22 0 soft fail
*SOFT 0 LCD + fail
54 *E12 150 %
55 *CALL.M 0 Off
56 *UNIT 0 mg/l

Communication

60 *COMM. 0.1 off/write prot.
*SET. 3.1 9600/odd
*ADDR. 00 00
61 *HOUR
62 *ERASE

General

70 *LOAD

Test and setup mode

80 *TEST

Appendix 10-3

IM 12J05D02-01E

10-4 Appendix

Error codes

Code Error description Possible cause Suggested remedy

E1 Response time failure. Calibration failed to Temperature unstable Avoid draughts and
reach stability in 1 hour direct sunshine
E2 Zero calibration out of limits Zero calibration not properly performed Repeat carefully
Check limits ± 0.5 µA (±5.0nA)
E3 Slope calibration out of limits Calibration not properly performed Repeat carefully
Check limits 40 to 200 % Wrong membrane thickness set Check code 01
E4 Membrane failure Perforated membrane Replace and recalibrate
E7 Temperature too high Process temperature too high Check process
> 50 °C/122 °F Wrong sensor programmed Check model code sensor
Incorrect wiring Check connections and cable
E8 Temperature too low Process temperature too low Check process
< 0°C/32 °F Wrong sensor programmed Check model code sensor
Incorrect wiring Check connections and cable
E9 Cell current abnormal Sensor fault Check membrane
Galvanic : outside -10 to 50 µA Programming fault Check setup
Polarographic: outside -100 to 500 nA
E10 EEPROM write failure Fault in electronics Try again, if unsuccessful

contact Yokogawa
E12 Abnormal measured value. Wrong DO sensor or temperaure Check code 01, 02, 10,
The dissolved oxygen value (%sat.) sensor programmed. 12 and 54.
exceeds 150%. (or value set in Code 54) Incorrect wiring. Accurately perform calibration.
E15 Cable resistance influence to temperature Cable resistance too high Check cable
exceeds ±7.5°C (±13.5°F) Corroded contacts Clean and reterminate
Wrong sensor programmed Reprogram
E16 Call for maintenance inetrval time System not maintained in Perfrom maintenance
exceeded. preset time period Reset interval
E17 Output span too small Incorrect configuration by user Reprogram
E18 Table values make no sense Wrong data programmed Reprogram
E19 Programmed values outside acceptable limits Incorrect configuration by user Reprogram
E20 All programmed data lost Fault in electronics Contact Yokogawa
Very severe interference
E21 Checksum error Software problem Contact Yokogawa
E22 Alarm activation time exceeded Process control not effective Check control equipment
within set time Adjust value in code 47

IM 12J05D02-01E

11. Appendix 2 QUALiTY inSpeCTiOn

Quality
inspection
Standards

㩷

㩷

dO402G
dissolved Oxygen Converter

QiS 12J5d2-01e

1st Edition: Sep. 1998

6th Edition: Mar. 2007



1. Scope

This inspection standard applies to the DO402G Dissolved Oxygen Converter.

2. inspection items

2.1 Insulation resistance test
* 2.2 Dielectric strength test

2.3 Current output test

2.4 Contact operation test

2.5 Temperature indication check
* 2.6 Input current indication check

2.7 Atmospheric pressure indication check
Note: Items marked with an asterisk (*) may only be confirmed by a test certificate.

3. inspection Methods, Standards and Conditions

z Connect the testing circuit as shown in Figure 1. Allow the instrument to warm up for

at least 5 minutes before conducting the tests. For the connections for the insulation
resistance test, follow the instructions in Sections 3.1 and for the dielectric strength
test, follow the instructions in Section 3.2.

z Performance tests should be done in the inspection mode where the tests from

Section 3.3 through Section 3.7 take place in sequence and cannot be retraced. If the
reconfirmation of a test is needed, turn off the power to the converter, turn on the
power again, and enter the inspection mode to restart the tests.

3.1 insulation Resistance Test

Apply 500 V DC between the power supply terminals shorted together (1 and 2) and the
protective earth terminal outside of the case. The insulation resistance must be 100 M
or greater.

3.2 dielectric Strength Test

Apply 1390 V AC, an AC voltage of substantially sinusoidal waveform with a frequency of
50 Hz or 60 Hz, between the power terminals shorted together (1 and 2) and the
protective earth terminal outside of the case, for at least 2 seconds. The insulation must
withstand this voltage. (The sensed current should be 15 mA.)

3.3 Current Output Test

Use the following procedure to enter the inspection mode.
(1) Entering Service Code 87

a. Press the [] key. The message display will show “SETP.”
b. Press the [NO] key four times. The message display will show “SERV.”

c. Press the [YES] key. The data display will show “0

0” with the first digit of 0 flashing.

d. Press the [] key eight times. The data display will show “8

0” with the first digit of 8

flashing.

e. Press the [>] key once. The data display will show “80

” with the second digit of 0

flashing.

Appendix 2 11-1

IM 12J05D02-01E

11-2 Appendix 2

2/4

QiS 12J5d2-01e

f. Press the [] key seven times. The data display will show “87” with the second digit

of 7 flashing.

g. Press the [ENT] key. The message display will show “PASS.”

(2) Setting Password 070

a. Press the [>] key once. The data display will show “00

0” with the second digit of 0

flashing.

b. Press the [] key seven times. The data display will show “07

0” with the second

digit of 7 flashing.
c. Press the [ENT] key. The data display will show “HIF.”
d. Press the [YES] key. The message display will show a manufacturing control

number.

This is the inspection mode.

Press the [ENT] key until the message display shows “mA1+2.”

Each time the [ENT] key is pressed, the value on the data display increases in steps of

4.0, like “0.0,” “4.0,” “8.0,” up to 20.0. Check the current outputs 1 and 2. Corresponding
to the data display, the current output must be within the range shown in Table 1.

When the data display shows “12.0,” pressing the [ENT] key causes the message display
to show “RIPPLE” and the data display to remain unchanged. Press the [ENT] key again.
The message display will show “mA” and the data display “16.0.”

Table 1

Data Display Current Output 1 (mA DC) Current Output 2 (mA DC)

4.0 4 ±0.02 4 ±0.02

12.0 12 ±0.02 12 ±0.02

20.0 20 ±0.02 20 ±0.02

3.4 Contact Operation Test

Following Section 3.3, press the [ENT] key until the message display shows “JUMPER.”
Then press the [ENT] key once, the message display will show “WAIT” and LEDs S1,
S2, WASH/S3, and FAIL/S4 flash rapidly. Check that the message display shows and
LEDs turns on/off in the order as shown in Table 2 and that a message of “FAIL x” does

not appear.

Table 2

Message Display S1 S

2 WASH/S3 FAIL/S4

LED1 OFF ON ON OFF
LED2 ON OFF ON OFF
LED3 ON ON OFF OFF
LED4 ON ON ON ON

3.5 Temperature indication Check

Following Section 3.4, press the [ENT] key until the message display shows “PT1000.” In
this state, change the resistance of the decade resistance box as shown in Table 3 and
check the data display. The value on the data display must be within the range shown in
Table 3.

IM 12J05D02-01E

3/4

QiS 12J5d2-01e

Table 3

Temperature (°C)

Resistance (:)

Data Display (°C)

5 1019.5 5 ±0.3
25 1097.3 25 ±0.3
45 1174.7 45 ±0.3

3.6 input Current indication Check

Following Section 3.5, press the [ENT] key until the message display shows “GALVA1.”
Turn SW1 on. Change the current of the standard current generator and check the data
display. The value on the data display must be within the range shown in Table 4.

Table 4

Reference (µA) Data Display (µA)

0 0 ±0.05
8 8 ±0.05

16 16 ±0.05

Press the [ENT] key until the message display shows “GALVA2.” Change the current of

the standard current generator and check the data display. The value on the data display
must be within the range shown in Table 5.

Table 5

Reference (µA) Data Display (µA)

10 10 ±0.1
30 30 ±0.2
50 50 ±0.2

Turn SW1 off. Press the [ENT] key until the message display shows “POLAR1.” Change
the current of the standard current generator and check the data display. The value on
the data display must be within the range shown in Table 6.

Table 6

Reference (nA) Data Display (nA)

0 0 ±0.2

80 80 ±0.2

160 160 ±0.2

Press the [ENT] key until the message display shows “POLAR2.” Change the current of

the standard current generator and check the data display. The value on the data display
must be within the range shown in Table 7.

Table 7

Reference (nA) Data Display (nA)

100 100 ±0.2
300 300 ±1
500 500 ±1

Appendix 2 11-3

IM 12J05D02-01E

11-4 Appendix 2

4/4

QiS 12J5d2-01e

3.7 Atmospheric pressure indication Check

Following Section 3.6, press the [ENT] key until the message display shows “PRESS.”
Check that the data display indication at this time is within the range from 900 (hPa) to

1100 (hPa).
Press the [ENT] key. The message display will show “READY.”

Continue to press the [ENT] key to return to normal measurement mode.

COnTACT

FAiL S3 S2 S

1

3 2 1 3271 72 51 52 41 42 31

11
T

1

12

T

2

61

62 6

5 66

15Re13

ie

17

+

-

+

-

mA 1 mA 2

Figure 1 Testing Circuit and Test equipment

dO402G Converter

+

-

digital
Multimeter

Current Output 1

300:

1%

+

-

digital
Multimeter

300:

1%

Current Output 2

decade
Resistance Box

a

power Supply

Standard Current
Generator

+

-

SW1

IM 12J05D02-01E

Appendix 2 11-5

IM 12J05D02-01E

Customer

4

5

1

8

15

13

10

11

14

9

7

12

3

2

Item Part No. Qty Description

1 K9313DW 1 Cover Assembly
2 K9215DB 1 Hingepin
3 K9663MC 1 Flat Cable
*4 K9664BU 1 Digital Assembly
*5 Analog Assembly
K9664HA 1 For 100 V AC
K9664HB 1 For 115 V AC
K9664HC 1 For 230 V AC
7 Housing
K9672DA 1 Polyuretane baked finish
K9672DB 1 Epoxy baked finish
8 K9663MM 1 Cable Gland Assembly
9 Fuse (Time Lag Fuse)
A1105EF 1 For 100 V AC Power, 0.200 A,T
A1105EF 1 For 115 V AC Power, 0.200 A,T
A1103EF 1 For 230 V AC Power, 0.100 A,T
10 A1565EF 1 Fuse Holder
11 K9672BJ 1 Bracket Assembly
12 K9664DH 1 Stainless steel screw assembly to fix cover

13 K9664DK 1 Screw Assembly
14 Bracket Assembly for Analog Board
K9664CH 1 For 100 V AC
K9664CJ 1 For 115 V AC
K9664CK 1 For 230 V AC
15 K9664AR 1 Bracket Assembly for Digital Board
16 Adapter Assembly
K9171SU 1 For G1/2 screw when /AFTG specified.
K9316AF 1 For 1/2NPT screw when /ANSI specified.

* Do not exchange these parts. Call serviceman.

16

Maintenance
Parts List

Model DO402G [Style: S3]
Dissolved Oxygen Converter

All Rights Reserved, Copyright © 2007, Yokogawa Electric Corporation.
Subject to change without notice.

CMPL 12J05D02-03E

1st Edition : Mar. 2007 (YK)

2
3

4

5

3

1

7

8

9

6

3

Item Part No. Qty Description

1 K9171SS 1 Mounting Set (/U)
2 Y9608KU 4 Screw
3 D0117XL-A 1 U-Bolt Assembly
4 K9171SY 1 Plate
5 K9171SX 1 Bracket

6 K9171ST 1 Mounting Set (/PM)
7 Y9520LU 2 Screw
8 K9171SW 2 Bracket
9 Y9608KU 4 Screw

10 Sun Protection Cover
K9664CA 1 Cabon steel (/H3)
K9664CC 1 Stailess steel (/H4)

Pipe/Wall Mounting Hardware
(Option Code : /U)

Panel Mounting Hardware
(Option Code : /PM)

10

Sun Protection Cover
(Option Code: /H3, /H4)

CMPL 12J05D02-03E

1st Edition : Mar. 2007 (YK)

Revision Record

Manual Title : Model DO402G Dissolved Oxygen Converter [Style: S3]
Manual Number : IM 12J05D02-01E

Edition Date Remark (s)

1st Apr. 2003 Newly published
2nd Feb. 2004 Style changed to S2
3rd Sep. 2006 On p.ii, After-sales Warranty modified.; On p.2-3, Operating specifications

modified.; On p.3-2, Housing dimensions of Fig. 3.01 modified.; On p.3-4, Fig.

3.04 Wiring Diagram modified.; On p.6-4, Tips for water calibration added.; On

p.6-6, Some error corrected.
4th Mar. 2007 All over revised. (Style of DO402G changed to S3.)
5th Jul. 2007 Page 2-2: Addition of CSA certified to item. M. Safety and EMC conforming

standards; Page 2-3: Some of G. Housing description revised; Page 3-3:

Addition of CSA certified to Sec. 3.2 Wiring; Page 3-4: The torque to tighten

frontplate screws added.
6th Oct. 2007 Appendix 2 Quality Inspection added.

IM 12J05D02-01E

User’s

Model DO402G [Style: S3]

Manual

Dissolved Oxygen Converter

Supplement

Thank you for selecting our Model DO402G [Style: S3] Dissolved Oxygen Converter.
User's Manual, IM 12J05D02-01E, 6th Edition, supplied with the product, some revisions/additions have been
made. Please replace the corresponding pages in your copy with the attached, revised pages.

Revisions:

- PREFACE, Addition of "How to dispose the batteries".

- Page 2-2, Some revision of M. Safety and EMC conforming standards (description for EMC revised).

- Page 4-4, Figure of Section 4-4. "Display functions (default)" modified.

- Page 5-16, Explanation of the code 21 modified.

- Page 5-25, Some revision of the code 53 (*Err.16 error setting).

- Page 6-1, Caution of calibration added to Sec.6.

- Page 6-4, Note for water calibration method of Sec. 6-3-2 modified.

All Rights Reserved, Copyright © 2007, 5th Edition: Jun. 2011 (YK)

Subject to change without notice.

IM 12J05D02-01E

6th Edition

This symbol indicates that the operator must refer to the instructions in this manual in order to prevent

WARNING

CAUTION

the instrument (hardware) or software from being damaged, or a system failure from occurring.

This symbol gives information essential for understanding the operations and functions.

This symbol indicates Protective Ground Terminal

This symbol indicates Function Ground Terminal (Do not use this terminal as the protective ground

terminal.)

This symbol indicates Alternating current.

This symbol indicates Direct current.

Warranty and service

Yokogawa products and parts are guaranteed free from defects in workmanship and material under
normal use and service for a period of (typically) 12 months from the date of shipment from the manufac­turer. Individual sales organizations can deviate from the typical warranty period, and the conditions of
sale relating to the original purchase order should be consulted. Damage caused by wear and tear, inad­equate maintenance, corrosion, or by the effects of chemical processes are excluded from this warranty
coverage.
In the event of warranty claim, the defective goods should be sent (freight paid) to the service depart­ment of the relevant sales organization for repair or replacement (at Yokogawa discretion). The following
information must be included in the letter accompanying the returned goods:

• Part number, model code and serial number

• Original purchase order and date

• Length of time in service and a description of the process

• Description of the fault, and the circumstances of failure

• Process/environmental conditions that may be related to the installation failure of the device

• A statement whether warranty or non-warranty service is requested

• Complete shipping and billing instructions for return of material, plus the name and phone number of a
contact person who can be reached for further information.

Returned goods that have been in contact with process fluids must be decontaminated/disinfected before
shipment. Goods should carry a certificate to this effect, for the health and safety of our employees.
Material safety data sheets should also be included for all components of the processes to which the
equipment has been exposed.

How to dispose the batteries:

This is an explanation about the new EU Battery Directive (DIRECTIVE 2006/66/EC). This directive is
only valid in the EU. Batteries are included in this product. Batteries incorporated into this product cannot
be removed by yourself. Dispose them together with this product. When you dispose this product in the
EU, contact your local Yokogawa Europe B.V.office. Do not dispose them as domestic household waste.
Battery type: silver oxide battery

Notice:
The symbol (see above) means they shall be sorted out
and collected as ordained in ANNEX II in DIRECTIVE 2006/66/EC.

IM 12J05D02-01E

IM 12J05D02-01E

2-2 Specification

J. Contact outputs

- General : Four (4) SPDT relay contacts
with LED indicators. For S1,
S2, and S3, the LED is on
when relay is powered.
NOTE:
For S4 (FAIL) LED lights when
power is removed (Fail safe).

Contact outputs configurable

for hysteresis and delay time.

- Switch capacity

: Maximum values 100 VA,

250 V AC, 5 Amps.
Maximum values 50 Watts,
250 V DC, 5 Amps.

- Status : High/Low process alarms,
selected from process
parameters and temperature.
Contact output is also available
to signal “Hold Active”

- Control function

: On/Off
PI pulsed Proportional duty cycle control

with integral term.

PI frequency Proportional frequency control

with integral term. In addition
wash cleaning control signal on
S3, and FAIL alarm for system
and diagnostic errors on S4

K. Contact input : Remote wash cycle start.

L. Power supply

Supply voltage rating

: 100, 115, 230 VAC

Applicable range

: 85 to 115, 97.8 to 132.2, 85 to 115, 97.8 to 132.2,85 to 115, 97.8 to 132.2,

195.5 to 264.5 VAC

Supply frequency rating

: 50 / 60 Hz

Applicable range

: 50 Hz ± 5% / 60 Hz ± 5%

Power consumption

: Maximum 10 VA for steady

operation

M. Safety and EMC conforming standards

,

Safety : conforms to EN 61010-1,

CSA C22.2 No.1010.1 certified

EMC : EN 61326-1 Class A, Table 2
(For use in industrial locations) (Note 1),

EN 61326-2-3

EN 61000-3-2 Class A
EN 61000-3-3

Installation altitude: 2000 m or less
Category based on IEC 61010: II (Note 2)

Pollution degree based on IEC 61010:2 (Note

2)

Note 1:

Note 2:

N. Shipping details

: Package size w x h x d

2-2. Operating specifications

A. Performance : DO (at t process = 25 °C)

- Linearity : ± 0.03 mg/l or ± 0.5%FS,

- Repeatability: ± 0.03 mg/l or ± 0.5%FS,

- Accuracy : ± 0.05 mg/l or ± 0.5%FS,

B. Performance : Temperature (Pt1000, PB36,

22kNTC)

- Linearity : ± 0.3 ºC

- Repeatability : ± 0.1 ºC

- Accuracy : ± 0.3 ºC

Performance : Temperature (Pt100)

- Linearity : ± 0.4 ºC

- Repeatability : ± 0.1 ºC

- Accuracy : ± 0.4 ºC

Note on performance specifications:

The specifications are expressed with sim-

ulated inputs, because the DO402G can
be used with many different sensors with
their unique characteristics.
The following tolerance is added to above
performance.
mA output tolerance : ± 0.02 mA of
"0/4 - 20 mA"
Digital display tolerance : +1 digit

C. Response time

0- 90% : 10 s

D. Ambient operating temperature

: -10 to +55 °C (14 to 131 ºF)°C (14 to 131 ºF)C (14 to 131 ºF)

This instrument is a Class A product,
and it is designed for use in the
industrial environment. Please use
this instrument in the industrial
environment only.
Installation category, called over­voltage category, specifies impulse
withstand voltage. Category II is for
electrical equipment.
Pollution degree indicates the degree
of existence of solid, liquid, gas or
other inclusions which may reduce
dielectric strength. Degree 2 is the
normal indoor environment.

290 x 300 x 290 mm.

11.5 x 11.8 x 11.5 in.
Packed weight approx.

2.5 kg (5lb).

whichever is greater

whichever is greater

whichever is greater

4-4 Operation

YES

YES

NO

MODE

NO

YES

YES

NO

NO

YES

NO

YES NO

YES NO

DISPLAY

HOLD

AIR.CAL

H2O.CAL

NO

NO

NO

NO

NO

NO

NO

NO

YES

YES

NO

YES

NO

YES

NO

YES

NO

YES

NO

YES

NO

YES

NO

YES

NO

DISPLAY

DISPLAY

DISPLAY

DISPLAY

DISPLAY

DISPLAY

DISPLAY

DISPLAY

MAN.CAL

YES

NO

NO

NO

YES

NO

NO

YES

NO

NO

YES

NO

NO

YES

NO

(See H2O
calibration
Chapter 6)

MEASURE

H2O.CAL

DISPLAY
HOLD

AIR.CAL

When enabled in
Hold (SET HOLD)
mode.

Setpoint adj. also.
when enabled
in service code 51

(See Manual
calibration
Chapter 6)

Process

temperature

Barometric

pressure

Software release

number

Slope

Cell current

Wash start in maintenance mode.
when enabled
in service code 51

Display Access

% Saturation

Current

output 1

Manual temp.
when enabled
in service code 13

Manual press.
when enabled
in service code 51

(Note 1)

(Note 2)

MAN.CAL

(See Air
calibration
Chapter 6)

Note 1: Manual temperature compensation menu

The menu can be displayed in maintenance mode.
This can be done by enabling the function in Service Code 13.
Manual temperature compensation menu is displayed and
temperature can be entered manually.

Note 2: Pressure is in bars.

Default: 1.013 bar

Setting range: 0.500 to 5.000 bar

Current
output 2

Press YES to fix

the selected second

line of display

4-4. Display functions (default)

IM 12J05D02-01E

IM 12J05D02-01E

5-16 Parameter setting

5-3-2. Temperature functions

Code 10 *T.SENS Select temperature sensor to suit the measuring probe. Refer to instructions

with DO sensor for which temperature sensor is used.

Code 11 *T.UNIT Select °C or °F for temperature display.

Code 12 *T.ADJ Adjust offset in temperature measurement when the sensor is at a stable

known value.

Code 13 *T.MAN Enable and set manual temperature compensation.

After the manual temperature set menu has been displayed, enter
temperature signals and press the [ENT] key to set. If the manual temperature
compensation is enabled, the temperature set menu is displayed in
maintenance mode.

The maximum and minimum slope values that may be entered depend on the nominal current from serv­ice code 01.
Example : When nominal current = 3.75 µA the maximum and minimum slope calibration values

that may be entered are: Maximum 3.75 x 2 = 7.5 µA

Minimum 3.75 x 0.4 = 1.5 µA

5-3-3. Calibration functions

Code 20 *∆T.SEC Set stability parameters for calibration. A greater time, and/or a smaller step

gives

*∆mg/l greater stability before a calibration can be accepted. Use caution, however, to

avoid very long calibration times.

Code 21 *0.CAL In a range where the zero point error has no impact, such as in an aerobic tank

with high dissolved oxygen concentrations, a zero calibration is not necessarily
required if a zero check is performed, because a zero point change is smaller
than a span point change.

However, it is recommended to perform a zero calibration when a new sensor

is installed, when the membrane is replaced, or in a place where dissolved

oxygen concentrations are low, such as in an anaerobic tank.
NOTE:
After zero calibration is performed, when a zero calibration is disabled in code

21 (*0.CAL), zero point will be back to default value.

Code 22 *ZERO Zero current values can be entered manually. If a zero calibration is made in

maintenance mode, a zero current value will be automatically reset.
NOTE:
A zero current value is displayed only when a zero calibration is enabled in

code 21.
*SLOPE Slope values can be manually entered with current values. If a span calibration

is made in maintenance mode, slope values will be automatically reset.
NOTE:
Slope values can be displayed with current values. When span check functions

are enabled in code 02, the above current values are converted to % values

and compared with the set values.

Slope % = current sensitive current /reference sensitive current

Parameter setting 5-25

Code Display Function Function detail X Y Z Default values

User Interface

50 *RET Auto return No return to meas. from HOLD 0 1

Return to meas after 10 min 1

51 *MODE add. to MAINT Setpoint adj. disabled 0 0.0.0

Setpoint adj. also in MAINT 1

Wash start disabled 0

Wash start in maintenance mode 1

Manual pressure disabled 0

Manual pressure enabled 1

52 *PASS Password Direct access to MAINT 0 0.0.0

MAINT protected by password #

Direct access to COMM 0

COMM protected by password #

Direct access to SERV 0

SERV protected by password #

Pass: 111 for #=1,
333 for #=2,
777 for #=3,
888 for #=4,
123 for #=5,
957 for #=6,
331 for #=7,
546 for #=8,
847 for #=9

53 *Err.01 Error setting Response & Time failure Soft fail 0

Zero calibration Hard fail 1 1 Hard

*Err.03 Slope calibration Soft fail 0

Slope calibration Hard fail 1 1 Hard

*Err.04 Membrane failure Soft fail 0

Membrane failure Hard fail 1 1 Hard

*Err.07 Temperature sensor open Soft fail 0

Temperature sensor open Hard fail 1 1 Hard

*Err.08 Temp. sensor shorted Soft fail 0

Temp. sensor shorted Hard fail 1 1 Hard

*Err.09 Cell current abnormal Soft fail 0

Cell current abnormal Hard fail 1 1 Hard

*Err.12 Abnormal measured value Soft fail 0

Abnormal measured value Hard fail 1 1 Hard

*Err.16 Cell for maintenance Soft fail 0 0 Soft

interval time exceeded

Cell for maintenance Hard fail 1

interval time exceeded

*Err.22 Control time-out Soft fail 0 0 Soft

Control time-out Hard fail 1

*SOFT LCD Fail Constant 0 0 LCD Fail

LCD only 1

54 *E12 overrange limit E12 active at 0 - 300 % sat (Note) 150%

55 *CALL.M E16 setting No call for maintenance 0 0

Call for maint. enabled 1

E16 message after 1- 250 days 30

56 *UNIT PV unit Unit of measurement mg/l 0 0

Unit of measurement ppm 1

Unit of measurement % sat. 2

57-59 Not used

*Err.02 Zero calibration Soft fail 0

Response & Time failure Hard fail 1 1 Hard

Note: For setting a value greater than 199.9, move the decimal point. For a value greater than 200%,

decimal places cannot be used.

IM 12J05D02-01E

Calibration 6-1

6. CALIBRATION PROCEDURE

Calibration of the dissolved oxygen analyzer is performed in the following situations:

• When a new dissolved oxygen sensor is installed.

• When the membrane is replaced and/or the electrolyte solution is replaced

• When the measuring error after cleaning exceeds the acceptable deviation from reference method

• When error message E12 or E16 indicates the need for maintenance
Note:
When a new sensor is installed, when the membrane is replaced, and/or the electrolyte solution is
replaced, it may take some time for the electrodes to stabilize due to the initial electrolysis. In particular,
a zero calibration should be performed after the electrodes are exposed to the air or immersed in sam­ple water for about half a day. When the sensor cable terminals 13 and 15 are shorted together before
installation, the time for the zero point to stabilize can be reduced.

6-1. General

6-1-1. Calibration methods

There are three methods for calibration of the EXA dissolved-oxygen analyzer: air calibration, water cali­bration and manual calibration.

Air calibration

This is the most common and easiest way to calibrate the analyzing system. The calibration is done in

AIR.CAL mode in maintenance level.

Water calibration

This is the traditional way to calibrate dissolved oxygen analyzers in laboratory environment. . Accurate
results can be obtained if the calibration is performed carefully. The water calibration may include a zero
calibration if so selected in service code 21. Normally only a zero check is performed without calibration,
since a good sensor has no zero signal.
Water calibration is not possible in salt water unless salinity compensation is activated in service code

04. The calibration is done in H2O.CAL mode in maintenance level.

NOTE:
In normal industrial environment better results are obtained with air calibration, which is therefore

the recommended method.

Manual calibration

This is a calibration method whereby the sensor is not exposed to a calibration fluid, but is calibrated
by comparison with a reference method. This reference method is normally a laboratory analysis of the
water sample: either by iodometric titration according ISO 5813 or an electrochemical method according
ISO 5814.
The calibration is done in MAN.CAL mode in maintenance level.

IM 12J05D02-01E

6-4 Calibration

6-3. Calibration procedure using water calibration method

6-3-1. Preparation

Move the sensor to a maintenance site and wash off any dirt on the membrane. Lightly wipe off any
remaining water from the membrane with a soft tissue.

Prepare the necessary equipment and reagents to be used for the span and (if required) zero calibration.

Equipment for span calibration includes:

• beaker or bucket

• magnetic stirrer or other means of agitating the water

• Demineralized water or salty process water if salinity compensation is activated

• Air supply pump (aquarium pump)

• Glass diffuser to generate small air bubbles

NOTE:
It takes 15 to 30 minutes of aeration before it can be assumed that the water is fully saturated with air.

Reagent for zero calibration:

• Sodium sulfite

• demineralized water

The zero oxygen solution contains 20- 30 grams of sodium sulfite per liter.

6-3-2. Calibration operation (water calibration method)

If both zero and span calibration are used, it is better to start with span calibration in spite of normal
calibration sequence with analog instrumentation. Otherwise the sensor must be rinsed off carefully to
prevent ingress of oxygen absorbing sulfite in the aerated water.

NOTE:
Zero calibration in the sodium sulfite solution takes a long time. Even after CAL.END is displayed,

wait 40 to 50 minutes and then press the YES key. If the YES key is pressed without waiting, the
indicator may show a minus reading during measurement. In an aerobic tank with high dissolved
oxygen concentrations, a zero calibration is not required if a zero check is performed, because the
indicating error is so insignificant that it does not affect the measurement results. There will be no
problem if the electrodes are immersed in a zero solution for about 10 minutes and the indication
falls below 1 mg/l. However, it is recommended to wait for about 60 minutes before performing
a zero calibration when a new sensor is installed, when the membrane is replaced, or in a place
where dissolved oxygen concentrations are low, such as in an anaerobic tank. If the solubility
does not fall below 1 mg/l even after waiting for about 10 minutes, remove the sensor and clean it,
and replace the membrane and/or replace the electrolyte solution.

Calibration may take longer than 10 minutes. Before starting the calibration procedure, check the

setting of Auto Return (*RET.) in Service Code 50. It is recommended to set the Auto Return to “0”
(No return to meas. from HOLD). After the calibration procedure has been completed, set the Auto
Return to the desired setting in Service Code 50.

IM 12J05D02-01E