Converter for Dual Cell
Conductivity and Resistivity
IM 12D08E02-01E
IM 12D08E02-01E
4th Edition
PREFACE
DANGER
WARNING
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.
CAUTION
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.
DANGER
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.
This symbol indicates that the operator must refer to the instructions in this manual in order to prevent
the instrument (hardware) or software from being damaged, or a system failure from occurring.
CAUTION
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.
Customer Maintenance Parts List (for Style: S2) ..................CMPL 12D08E02-02E
Revision Record ..........................................................................................................i
IM 12D08E02-01E
Introduction 1-1
1. INTRODUCTION AND GENERAL DESCRIPTION
The Yokogawa EXA 402 is a 4-wire converter 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 nameplate affixed to the top of the display board of the instrument
agrees with your order.
WARNING
The nameplate will also contain the serial number and power supply selection.
Be sure to apply correct power to the unit.
50/60Hz MAX.10VA
115VAC
0-20mADC or 4-20mADC
Figure 1-1. Nameplate
MODEL
SUFFIX
STYLE
DC402G
Made in Japan
SUPPLY
OUTPUT
No.
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 English
Optional mounting hardware when specified (See model code)
IM 12D08E02-01E
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 dos-
ing/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 closely 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 five 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.
IM 12D08E02-01E
2. DC402G SPECIFICATIONS
2-1. General specifications
A. Input specifications
: Two inputs , each 2-electrode
measurement with square wave
excitation, using cell constants(C)
from 0.008 to 50.0 cm
-1
, with up
to 60 metres (200ft) connection
cable.
B. Detection method
: Frequency, read-pulse position
and reference voltage are
dynamically optimized.
C. Input rangesMinimum : 1µS x C at process tem perature
(underrange 0.000 µS/cm).
Maximum : 25 mS x C at process tem perature
(overrange 30 mS x C).
-Resistivity : 0.00 kΩ - 999 MΩ/C at 25 °C
(77 °F) reference temperature.
Minimum : 40 Ω/C at process temperature
(underrange 0.001 kΩ x cm).
Maximum : 1 MΩ/C at process tem pera ture
(overrange 999 MΩ x cm).
-Temperature
Pt1000 : -20 to +250 °C (0 to 500 °F)
Pt100 and Ni100
: -20 to +200 °C (0 to 400 °F)
8K55 NTC : -10 to +120 °C (10 to 250 °F)
PB36 NTC : -20 to +120 °C (0 to 250 °F)
D. SpanConductivity/Resistivity
- Min. span : 0.010 µS/cm; 0.001 kΩ x cm
up to 90% maximum zero
suppression.
- Max. span : 1500 mS/cm; 999 MΩ x cm
Ratio (cell1/cell2)
- Min. span : 00.0
- Max. span : 19.99
Difference (cell1- cell2)
- Min. span : 0.010 µS/cm
- Max. span : 400 mS/cm
% Passage (100x[cell2/cell1] )
- Min. span : 00.0
- Max. span : 199.9
% Rejection (100x[( cell1-cell2)/cell1] )
- Min. span : 0.1
- Max. span : 400
Specification 2-1
% Deviation (100x[ (cell2-cell1)/cell1] )
- Min. span : 0.1
- Max. span: 400
VGB-directive 450 L
- Min. span : 1.0 pH
- Max. span : 14.0 pH
Temperature
- Min. span : 25 °C (50 °F)
- Max. span : 250°C (500 °F)
Difference Temperature
- Min. span : 25 °C (50 °F)
- Max. span : 250 °C (500 °F)
E. Transmission Signals
: Two isolated outputs of 0/4-20
mA DC with common negative.
Max. load : 600 Ω.
Auxiliary output can be chosen
from conductivity, linearized
conductivity, resistivity,
temperature, differential
temperature calculated value
or PI control of conductivity/
resistivity.
Burn up (22 mA) or Burn down
(0/3.5 mA) to signal failure.
F. Temperature compensation
: Automatic, for temperature
ranges mentioned under C
(input ranges).
- Reference temperature :
programmable from 0 to 100 °C
or 30 to 210 °F (default 25 °C).
G. Compensation algorithm
:
According IEC 60746-3
NaCl tables (default). Two
independent user programmable
temperature coefficients, from
0% to 3.5% per °C (°F) by
adjustment or calibration.
- Matrix compensation : with conductivity function
of concen-tration and
temperature. Choice of 5
preprogrammed matrixes
and a 25-points userprogrammable matrix.
IM 12D08E02-01E
2-2 Specification
H. Display: Custom liquid crystal display,
with a main display of 3
1
/2
digits 12.5 mm high. Message
display of 6 alpha numeric
characters, 7 mm high. Warn-
ing flags and units (mS/cm,
kΩ·cm, µS/cm and MΩ·cm) as
appropriate.
I. Contact Outputs
- General : Four (4) SPDT relay contacts
with LED indicators. For S1,
S2, and S3, the LED is on
when relay power is removed.
NOTE: For S4 (FAIL) LED
lights when relay is
deenergised (Fail
safe).
Contact outputs configurable
for hysteresis and delay time.
- Switch capacity
: Maximum values 100 VA,
250 VAC, 5 Amps.
Maximum values 50 Watts,
250 VDC, 5 Amps.
- Status : High/low process alarms,
selected from conductivity,
resistivity 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.
(PI control on Conductivity/
Resistivity only) In addition
FAIL alarm for sys tem and
diagnostic errors on S4.
K. Shipping Details
Package size
: W x H x D
290 x 300 x 290 mm.
11.5 x 11.8 x 11.5 in.
Packed weight
:approx. 2.5 kg (5lb).
2-2. Operating specifications
A. Performance : Conductivity
- Linearity : ± 0.5 % FS
- Repeatability : ± 0.5 % FS
- Accuracy : ± 0.5 FS
Performance : Resistivity
- Linearity : ± 0.5 FS
- Repeatability : ± 0.5 % FS
- Accuracy : ± 0.5 % FS
Performance :TemperaturewithPt1000Ω,
Ni100ΩandPB36NTC
- Linearity : ± 0.3 °C
- Repeatability : ± 0.3 °C
- Accuracy : ± 0.3 °C
Performance :TemperaturewithPT100Ω
and8k55Ω
- Linearity : ± 0.4 °C
- Repeatability: ± 0.4 °C
- Accuracy : ± 0.4 °C
Note; The following tolerance are added to
above performance.
mA output tolerance : ± 0.02 mA of
"0/4 - 20 mA"
Digital display tolerance: +1 digit
Performance : Temperature compensation
- NaCl table : ± 1 %
- Matrix : ± 3 %
- Step response: 90 % (< 2 decades) in ≤ 6
seconds
B. Ambient operating temperature
: -10 to +55 °C (14 to 131 ºF)
J. Power Supply
Supply voltage rating: 115, 230 VAC
Applicable range: 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
IM 12D08E02-01E
C. Storage temperature
: -30 to +70 °C (-20 to 160 ºF)
D. Humidity
: 10 to 90% RH non-condensing
E. Housing
: Cast aluminium case
with chemically resistant
coating, cover with flexible
polycarbonate window. Case
color is off-white and cover is
moss green. Cable entry is via
six PG13.5 nylon glands. Cable
terminals are provided for up to
2.5 mm finished wires. Weather
resistant to IP65. Pipe wall or
panel mounting, using optional
hardware.
F. Data protection
: EEPROM for configuration and
logbook, and lithium battery for
clock.
G. Watchdog timer
: Checks microprocessor
H. Automatic safeguard
: Return to measuring mode
when no keystroke is made for
10 min.
I. Power interruption
: Less than 50 milliseconds no
effect.
J. Operation protection
: 3-digit programmable pass-
word.
K. Safety and EMC conforming standards
Safety :
conforms to EN 61010-1,
,
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
EMC Regulatory Arrangement in
Australia and New Zealand (RCM)
EN 55011 Class A, Group 1
Korea Electromagnetic
Conformity Standard Class A
한국 전자파적합성 기준
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: 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.
Specification 2-3
A급 기기ㅤ(업무용 방송통신기자재)
ㅤ이 기기는 업무용(A급) 전자파적합기기로서 판매자 또는
사용자는 이 점을 주의하시기 바라며, 가정외의 지역에서
사용하는 것을 목적으로 합니다.
Note 2: Installation category, called over-
voltage 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.
2-3. Model and suffix codes
Model
DC402G-----------------------Dual Conductivity
Type-1----------General
Power Supply
Voltage
Language-E-J----------
Options
Suffix
code
-1
-2
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
English
Japanese
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.
[Style: S2]
IM 12D08E02-01E
Installation and wiring 3-1
□ Hood (optional)
WARNING
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 total cable length should not exceed 60 meters (200 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 (nominal pipe diameter 50A)
144
(5.67)
184
(7.24)
144
(5.67)
Option code : /H□
72
(2.83)
(0.79)
20
23
(0.91)
220
(8.66)
112
(4.41)
Four M6 screws, 8 (0.31) deep
80
(3.15)
Adaptor for conduit work
(option code : /AFTG, /ANSI)
80
(3.15)
Figure 3-1. Housing dimensions and layout of glands
ABC
D
3636
(1.42)
Ground terminal
(M4 screw)
EF
(1.42)
Cable inlet port (21 (0.83) dia. holes)
equivalent to DIN PG13.5 cable gland
A : For sensor cable
B : For sensor cable
C : For output signal
(1.42)
36
38
D : For contact output (S3 and S4)
E : For contact output (S1 and S2)
Figure 3-3. Wall and pipe mounting diagram (Option Code: /U)
IM 12D08E02-01E
200
(7.87)
35
15
(1.38)
(0.59)
70
100
(2.76)
(3.94)
Installation and wiring 3-3
Figure 3-4. Internal view of EXA wiring compartment
DANGER
• Never apply power to the DC402G converter and other instruments connected to the DC402G
converter until all wiring is completed.
WARNING
• This product complies with the CE marking.
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 DC402G 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
DC402G 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 DC402G 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 12D08E02-01E
3-4 Installation and wiring
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 and outputs.
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 righthand 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.
WARNING
Always replace the screen plate over the power and contact outputs for safety and avoid
interference.
7. Connect the analog output(s) and the sensor input.
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
Sensor
cables
Contact
(S1,S2)
output cables
Sensor
cables
Power
cable
High voltage section
Analog
output cable
IM 12D08E02-01E
Installation and wiring 3-5
FRONT GLANDSREAR GLANDS
Sensors
0/4-20 mA
Output
signals
Contact
output
Contact
output
Contact
input
0/4-20 mA
Power
S1
S2
S3
S4/FAIL
DANGER
Figure 3-6. System configuration
3-3. Wiring the power supply
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 nameplate.
Remove the front cover by unscrewing the four screws to check this nameplate 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 12D08E02-01E
3-6 Installation and wiring
DANGER
CAUTION
71
S4
S3
S2
S1
C NC NO
72 73 51 52 53 41 43 31 33 42 32
250VAC
5A
100VA
250VDC
5A
50W
FUSE
115
230
250VAC; T 200mA
3 1 2
G N L
C NC NO C NC NO C NC NO
VAC
VAC
12 11 14 15 22 21
63 66 65 62 61 95 94 93 92 91
Sensor inputs
SENSOR 1
12 11 14 15
mA Outputs
CONT
SENSOR 2
mA OUTPUT
Relay Contacts Power Supply
Temp
Temp
mA2
mA1
Screen
250VAC; T 100mA
DC402 REFER TO INSTRUCTION MANUAL FOR CONNECTIONS
23
Screen
(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.
Please be sure to connect protective grounding of
DC402G 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.
mark (100Ω or less).
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 measured 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 12D08E02-01E
Installation and wiring 3-7
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 not activated as an alarm (off).
• 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.
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 is necessary to use screening/shielding on the output signal cables. Terminal 63 is used to connect the
shielding.
IM 12D08E02-01E
3-8 Installation and wiring
3-6. Sensor wiring
Refer to figure 3-9, which includes drawings that outline sensor wiring.
The EXA DC402G can be used with a wide range of commercially available sensor types if provided with
shielded cables, both from Yokogawa and other manufacturers. The sensor systems from Yokogawa fall
into two categories, the ones that use fixed cables and the ones with separate cables.
To connect sensors with fixed cables, simply match the terminal numbers in the instrument with the identification numbers on the cable ends.
Note that the DC402G uses the 2 electrode measuring principle. Yokogawa sensors and cables are prepared for compatibility with 4-electrode measuring systems. To avoid problems either cut off and insulate
the wires tagged 13 &16 or connect the wires in tandem 13 &14 into terminal 14 or 15 &16 into terminal
15.
CONDUCTIVITY RESISTIVITY CONVERTER
11 TEMPERATURE
12 TEMPERATURE
14 CELL
15 CELL
1
2
1
2
BROWN
BROWN
YELLOW/GREEN
RET
11 TEMPERATURE
12 TEMPERATURE
14 OUTER ELECTRODE
15 INNER ELECTRODE
SEPARATE SENSORS WITH WU40-LH.. CABEL
SX42-SX . . - . F SENSORS
NOTE: Use shielded cable
11 TEMPERATURE
12 TEMPERATURE
14 OUTER ELECTRODE
15 INNER ELECTRODE
SC4A... SENSORS WITH INTEGRATED CABEL
Figure 3-9. Sensor wiring diagrams
3-7. Sensor connection using junction box and extension cable
Where a convenient installation is not possible using the standard cables between sensors and convert-
er, a junction box and extension cable may be used. The Yokogawa BA10 junction box and the WF10
extension cable should be used. These items are manufactured to a very high standard and are necessary to ensure that the specifications of the system can be met. The total cable length should not exceed
60 metres (e.g. 10 m fixed cable and 50 m extension cable).
NOTE: Numbers 17 of both WF10 and BA10 do not need to be used.
IM 12D08E02-01E
Installation and wiring 3-9
t
11 12
TEMPERATURE
SENSOR
CELL
ELECTRODE
14
15
Sensor Inputs
mA Outputs
3-8. Other sensor systems
To connect other sensor systems, follow the general pattern of the terminal connections as listed below:
11 and 12 Always used for temperature compensation resistor input (Pt1000, Ni100, Pt100, PB36
and 8k55)
14 Normally used for the outer electrode
15 Used for inner electrode
In case a 4-electrode measuring system will be used, 14 and 16 should be used for the current elec-
trodes.Please ensure that shielded cabling will be used.
In figure 3-10 this is shown in a schematic way.
Figure 3-11. Terminal identification labels example
NO
NCC
S3
SENSOR 2
NO
NCC
S2
mA1
mA2
SCREEN
mA OUTPUTCONTSENSOR 1
333231434241535251737271
NO
NCC
S1
G
115 VAC
123
N
L
FUSE
250V
T200mA
IM 12D08E02-01E
3-10 Installation and wiring
Figure 3-12. Sensor cable connections
IM 12D08E02-01E
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 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 SERVICE. Now push the “YES” button. Selecting and entering “Service Code” num-
bers 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.
CALIB 1(2) Calibration with a standard solution or a sample 6
DISPLAY 1(2) Read auxiliary data or set message display 4
HOLD Switch hold on/off (when activated) 5
Commissioning SETPOINTS Adjust alarm setpoints 5
RANGE Adjust the output range 5
SET HOLD Activate the hold function 5
TEMP Select method of temperature compensation 5
Service SERVICE Fine tune the specialized functions of the 5
(Access to coded entries converter
from the commissioning
level)
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
4-2 Operation
Output hold flag
Main display
Message display
Key prompt flags
Selection keys
YES : Accept setting
NO : Change setting
Adjustment keys
YOKOGAWA
> : Choose digit to
adjust
^ : Adjust digit
ENT : Confirm change
Figure 4-1. DC402G operator interface
HOLDFAIL
k
mS/cm
M
YES NO
NOMODEYES
ENT
Broken line indicates area
that can be seen through
front cover
cm
cm
S/cm
ENT
Fail flag
MODE
MEASURE
CAL 1
CAL 2
DISPLAY 1
DISPLAY 2
HOLD
CONTACTS
S1
S2
S3
FAIL
MARKINGS
WITHIN
INCLOSURE
Menu pointer flags
Units
Commissioning
SETPOINTS
RANGE
SET HOLD
TEMP.
SERVICE
*
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.
SETPOINTS
CAL.1/CAL.2
DISP.1/DISP.2
HOLD
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 con-
firm 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.
IM 12J05D02-01E
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 commis-
sioning (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
Enter a 3-digit passcode as set in Service Code 52 to obtain access to the Commissioning Mode.
Service
From the commissioning menu, select *Service 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.
key. The display shows 000 and *PASS*
*
NOTE:
See Service Code 52 for the setting of passcodes.
4-4. Display example
The next page shows the sequence of button presses and screens displayed when working in default
configuration.
More or less options will be made available by the configuration of some service codes, or by choices
made in the Commissioning menu.
The following deviations are possible:
Items marked are omitted when switched off in commissioning mode and/or service code 51.
Temperature compensation will be displayed dependent on chosen compensation method: NaCl,
TC 2.1 or matrix.
DISP.2 only appears if mA2 is configured for a 2nd (different) temperature compensation or if %
by weight.2 is enabled in code 55.
W/W % only appears if switched on in service code 55.
IM 12J05D02-01E
Loading...
+ 56 hidden pages
You need points to download manuals.
1 point = 1 manual.
You can buy points or you can get point for every manual you upload.