YOKOGAWA SC402G User manual

User’s
Manual
IM 12D08N04-01E
Model SC402G
Conductivity and Resistivity
Converter
[Style : S2]
IM 12D08N04-01E
3rd Edition

1
Preface
IM 12D08N04-01E
Preface
In order to understand the functions of the SC402G 4-wire conductivity converter, be
sure to read this manual thoroughly before using it.
* The specifications and looks of this product are subject to change without notice, for
the purpose of improving it.
* This manual may not be copied without permission.
WARNING
Electric discharge
The EXA analyser 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 analyser 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
Contents of this manual are subject to change without notice.
3rd Edition: Sep. 2005 (YK)
All Rights Reserved, Copyright © Oct. 2000, Yokogawa Electric Corporation

IM 12D08N04-01E
2
Preface
The following safty symbols are used in the product as well as in this manual.
DANGER
This symbol indicates that the operator must follow the instructions laid out in this
manual in order to avoid the risk of personnel injury, electric shock, or fatalities. The
manual describes what special care the operator must exercise to avoid such risks.
WARNING
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 draws attention to information essential for understanding the operation and
functions.
NOTE
This symbol indicates information that complements the present topic.
SEE ALSO
This symbol identifies a source to which to refer.
Protective Ground Terminal. Be sure to ground equipment before use.
Function Ground Terminal (Do not use this terminal as the protective ground
terminal.). Be sure to ground equipment before use.
Alternating current

3
Preface
IM 12D08N04-01E
rAfter-sales Warranty
dDo not modify the product.
dDuring the warranty period, for repair under warranty carry or send the product to the
local sales representative or service office. Yokogawa will replace or repair any
damaged parts and return the product to you.
dBefore returning a product for repair under warranty, provide us with the model
name and serial number and a description of the problem. Any diagrams or data
explaining the problem would also be appreciated.
dIf we replace the product with a new one, we won’t provide you with a repair report.
dYokogawa warrants the product for the period stated in the pre-purchase quotation.
Yokogawa shall conduct defined warranty service based on its standard. When the
customer site is located outside of the service area, a fee for dispatching the mainte-
nance engineer will be charged to the customer.
dIn the following cases, customer will be charged repair fee regardless of warranty
period.
• Failure of components which are out of scope of warranty stated in instruction
manual.
• Failure caused by usage of software, hardware or auxiliary equipment, which
Yokogawa Electric did not supply.
• Failure due to improper or insufficient maintenance by user.
• Failure due to modification, misuse or outside-of-specifications operation which
Yokogawa does not authorize.
• Failure due to power supply (voltage, frequency) being outside specifications or
abnormal.
• Failure caused by any usage out of scope of recommended usage.
• Any damage from fire, earthquake, storms and floods, lightning, disturbances, riots,
warfare, radiation and other natural changes.
d Yokogawa does not warrant conformance with the specific application at the user
site. Yokogawa will not bear direct/indirect responsibility for damage due to a specific
application.
dYokogawa Electric will not bear responsibility when the user configures the product
into systems or resells the product.
dMaintenance service and supplying repair parts will be covered for five years after
the production ends. For repair for this product, please contact the nearest sales office
described in this instruction manual.

IM 12D08N04-01E
4
Preface

i
IM 12D08N04-01E
Table of Contents
Table of Contents
Preface .................................................................................................................... 1
rAfter-sales Warranty ......................................................................................... 3
1. Introduction and General Description .......................................................1-1
1-1. Instrument Check................................................................................................ 1-1
1-2. Application.......................................................................................................... 1-2
2. SC402G Specifications................................................................................2-1
2-1. General................................................................................................................ 2-1
2-2. Operating specifications ..................................................................................... 2-3
2-3. Model and suffix codes ...................................................................................... 2-4
3. Installation and Wiring ................................................................................3-1
3-1. Installation and dimensions ................................................................................ 3-1
3-1-1. Installation site........................................................................................... 3-1
3-1-2. Mounting methods ..................................................................................... 3-1
3-2. Preparation .......................................................................................................... 3-5
3-3. Wiring the power supply .................................................................................... 3-7
3-3-1. General precautions ................................................................................... 3-7
3-3-2. Access to terminal and cable entry ........................................................... 3-7
3-3-3. AC power................................................................................................... 3-8
3-3-4. Grounding the housing .............................................................................. 3-8
3-3-5. Switching on the instrument...................................................................... 3-8
3-4. Wiring the contact signals .................................................................................. 3-9
3-4-1. General precautions ................................................................................... 3-9
3-4-2. Contact outputs .......................................................................................... 3-9
3-5. Wiring the analog output signals ....................................................................... 3-9
3-5-1. General precautions ................................................................................... 3-9
3-5-2. Analog output signals ................................................................................ 3-9
3-6. Sensor wiring .................................................................................................... 3-10
3-7. Other sensor systems ........................................................................................ 3-11
4. Operation; Display Functions and Setting................................................4-1
4-1. Operator interface ............................................................................................... 4-1
4-2. Explanation of operating keys............................................................................ 4-2
4-3. Setting passcodes ................................................................................................ 4-3
4-3-1. Passcode protection ................................................................................... 4-3
4-4. Display example ................................................................................................. 4-3
4-5. Display functions ................................................................................................ 4-4
5. Parameter setting.........................................................................................5-1
5-1. Maintenance mode.............................................................................................. 5-2
5-1-1. Introduction................................................................................................ 5-2
5-1-2. Manual activation of Hold......................................................................... 5-3
5-1-3. Setpoint adjustment ................................................................................... 5-4
5-2. Commissioning mode ......................................................................................... 5-5
5-2-1. Introduction................................................................................................ 5-5

IM 12D08N04-01E
ii
Table of Contents
5-2-2. Setpoints..................................................................................................... 5-6
5-2-3. Range ......................................................................................................... 5-8
5-2-4. Hold ......................................................................................................... 5-10
5-2-5. Temperature compensation...................................................................... 5-12
5-2-6. Service ..................................................................................................... 5-14
5-3. Notes for guidance in the use of service coded settings ................................. 5-15
5-3-1. Parameter specific functions.................................................................... 5-16
5-3-2. Temperature measuring functions ........................................................... 5-18
5-3-3. Temperature compensation functions...................................................... 5-20
5-3-4. mA output functions ................................................................................ 5-22
5-3-5. Contact outputs ........................................................................................ 5-24
5-3-6. User interface........................................................................................... 5-28
5-3-7. Setting Time ............................................................................................ 5-30
5-3-8. General..................................................................................................... 5-30
6. Calibration ....................................................................................................6-1
6-1 When is calibration necessary? ........................................................................... 6-1
6-2. Calibration procedure ......................................................................................... 6-2
6-3. Calibration with HOLD active ........................................................................... 6-3
7. Maintenance .................................................................................................7-1
7-1. Periodic maintenance for the EXA 402 converter ............................................. 7-1
7-2. Periodic maintenance of the sensor.................................................................... 7-2
8. Troubleshooting...........................................................................................8-1
8-1. Diagnostics.......................................................................................................... 8-1
8-1-1. Off-line checks........................................................................................... 8-1
8-1-2. On-line checks ........................................................................................... 8-1
9. Spare Parts ...................................................................................................9-1
10. Appendix.....................................................................................................10-1
10-1. User setting for non-linear output table (code 31, 35 and 36) ...................... 10-1
10-2. User entered matrix data (code 22 to 28) ...................................................... 10-1
10-3. Matrix data table (user selectable in code 22) ............................................... 10-2
10-4. Sensor Selection ............................................................................................. 10-3
10-4-1. General................................................................................................... 10-3
10-4-2. Sensor selection ..................................................................................... 10-3
10-4-3. Selecting a temperature sensor .............................................................. 10-3
10-5. Setup for other functions ................................................................................ 10-3
10-6. USP Item 645 Water Purity Monitoring ........................................................ 10-4
10-7. User setting table ............................................................................................ 10-6
10-8. Configuration checklist for SC402G.............................................................. 10-8
Customer Maintenance Parts List [Style : S1] .................CMPL 12D08N04-01E
Customer Maintenance Parts List [Style : S2] .................CMPL 12D08N04-02E
Revision Record ..................................................................................................... i

IM 12D08N04-01E 1-1
1. Introduction and General Description
1. Introduction and General Description
The Yokogawa EXA 402 is a 4-wire converter designed for industrial process monitor-
ing, 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.
NOTE:
The textplate will also contain the serial number and power supply selection.
Be sure to apply correct power to the unit.
Made in Japan
MODEL
SUFFIX SUPPLY
OUTPUT
No.
SC402G
STYLE
Figure 1-1. Textplate
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 12D08N04-01E
1-2
1. Introduction and General Description
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. 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/
neutralisation system.
Yokogawa designed the EXA analyzer to withstand harsh environments. The converter
may be installed either indoors or outside because the IP65 (NEMA4X) 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 mount-
ing. Select an appropriate installation site to facilitate ease of operation. Sensors should
normally be mounted closely to the converter in order to ensure easy calibration and
peak performance.
The EXA is delivered with general purpose default settings 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 12D08N04-01E 2-1
2. SC402G Specifications
2. SC402G Specifications
2-1. General
A. Input specifications
: Two or four electrodes measurement with square wave excitation, using cell constants
from 0.008 to 50.0 cm-1
B. Detection method : Frequency, read-pulse position and reference voltage are dynamically optimized.
C. Input ranges
Conductivity
Minimum : 0 µS/cm
Maximum : 200 mS 3(Cell constant) (overrange 1999 mS/cm).
Resistivity
Minimum : 0.005 kΩ/ (Cell constant)
Maximum : 999 MΩ3cm
Temperature
Pt1000 : -20 to 250 °C (0 to 500 °F)
Pt100/Ni100 : -20 to 200 °C (0 to 400 °F)
8.55kΩNTC : -10 to 120 °C (10 to 250 °F)
PB36 NTC : -20 to 120 °C (0 to 250 °F)
D. Span Conductivity :min. 0.010 µS/cm,
max. 1999 mS/cm. (max 90% zero suppression)
Resistivity :min. 0.001 kΩ·cm
max. 999 MΩ·cm. (max 90% zero suppression)
Temperature : Dependent on temp. sensor type:
Sensor type min. max.
Pt1000 25 °C (50 °F) 250 °C (500 °F)
Pt100, Ni100 25 °C (50 °F) 200 °C (400 °F)
PB36NTC, 8.55kΩNTC25 °C (50 °F) 100 °C (200 °F)
The instrument is user programmable for linear or non-linear conductiv-
ity ranges.
E. Transmission signals: Two isolated outputs of 0/4-20 mA DC with common negative.
Maximum load 600 Ω.
Auxiliary output can be chosen from conductivity, resistivity or temperature
Burn up (22 mA) or Burn down (0/3.5 mA) to signal failure.
F. Temperature compensation
: Automatic, for temperature ranges mentioned under C (inputs).
Reference temp : programmable from 0 - 100 °C or 30 - 210 °F (default 25 °C).

IM 12D08N04-01E
2-2
2. SC402G Specifications
G. Compensation algorithm : According IEC 746-3 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 concentration and temperature. Choice out of 5
preprogrammed matrixes and a 25-points user-programmable matrix.
H. Display : Custom liquid crystal display, with a main display of 3 1/2 digits 12.5 mm high.
Message display of 6 alphanumeric characters, 7 mm high.
Warning 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 is powered.
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”
Status
Alarm, Fail ON
Alarm, Fail OFF
Power OFF
Contact S1~S3
LED NO NC
ON Closed Open
OFF Open Closed
OFF Open Closed
Contact S4
LED NO NC
ON Open Closed
OFF Closed Open
OFF Open Closed
T01.EPS
Contact status
Control function : On / Off
PI pulsed - Proportional duty cycle control with integral term.
PI frequency - Proportional frequency control with integral term.
In addition FAIL alarm for system and diagnostic errors on S4
J. Contact Input : Remote range switching to 10 times the programmed range.
Contact open : If impedance > 100 kΩ: Range 1
Contact closed : If impedance < 10 Ω: Range 2 (10 x Range 1)
K. Power Supply : 230 VAC ±15%, 50/60 Hz, maximum consumption 15 VA.
115 VAC ±15%, 50/60 Hz, maximum consumption 15 VA.
100 VAC ±15%, 50/60 Hz, maximum consumption 15 VA.
L. Input isolation : 1000 V AC or 2100 V DC
M. Weight: main unit: approximately 1.8kg
mounting brackets and fitttings: approximately 0.7kg
N. Dimensions 144 x 144 x 135 (mm)

IM 12D08N04-01E 2-3
2. SC402G Specifications
2-2. Operating specifications
A. Performance (under reference conditions with sensor simulation)
Converter output tolerance: 60.125% of output span
Conductivity (2 µS 3K cm-1 to 200 mS 3K cm-1)
- Linearity : 60.5%F.S.
- Repeatability : 60.5%F.S.
Conductivity (1 µS 3K cm-1 to 2 µS 3K cm-1)
- Linearity : 61%F.S.
- Repeatability : 61%F.S.
Resistivity (0.005kΩ/ K cm-1 to 0.5MΩ/ K cm-1)
- Linearity : 60.5%F.S.
- Repeatability : 60.5%F.S.
Resistivity (0.5MΩ/ K cm-1 to 1MΩ/ K cm-1)
- Linearity : 61%F.S.
- Repeatability : 61%F.S.
Note: "F.S." means maximum setting value of converter output. "K" means cell constant. YOKOGAWA
provides conductivity sensors which cell constant are 0.1 to 10 cm-1.
Temperature (Pt1000, PB36 NTC, Ni100)
- Linearity : 60.3°C (190°C or more with Pt1000; 61°C)
- Repeatability : 60.3°C (190°C or more with Pt1000; 61°C)
- Accuracy : 60.3°C (190°C or more with Pt1000; 61°C)
Temperature (Pt100, 8.55kΩNTC)
- Linearity : 60.4°C
- Repeatability : 60.4°C
- Accuracy : 60.4°C
Temperature compensation
- NaCl table : 61°C
- Matrix : 63°C
Step response : 90 % (< 2 decades) in 3 seconds
B. Ambient operating temperature
: -10 to +55 °C (10 to 130 ºF)
C. Storage temperature : -30 to +70 °C (-20 to 160 ºF)
D. Humidity : 10 to 90% RH non-condensing

IM 12D08N04-01E
2-4
2. SC402G Specifications
E. Housing : Cast aluminium case with polyurethane baked finish, cover with flexible polycar-
bonate window. Case color is Frosty-white (Equivalent to Munsell 2.5Y8.4/1.2)
and cover is Deepsea Moss green (Equivalent to Munsell 0.6GY3.1/2.0). Cable
entry is via six 1/2 inch nylon glands. Cable terminals are provided for up to 2.5
mm2finished wires. Weather resistant to IP65 and NEMA 4X standards. Pipe
wall or panel mounting, using optional hardware.
F. Data protection : EEPROM for configuration
G. Automatic safeguard : Return to measuring mode when no keystroke is made for 10 min.
H. Power interruption : Less than 50 milliseconds no effect.
More than 50 milliseconds reset to measurement.
I. Operation protection : 3-digit programmable password.
2-3. Model and suffix codes
Model Suffix Code Option Code Description
SC402G
Power supply voltage
Language
Optional Mounting brackets
-1 .................................................
-2 .................................................
-5 .................................................
-E ........................................
-J ........................................
/U .......................
/PM ....................
/H3 .....................
/H4 .....................
/SCT ..................
/AFTG ................
/ANSI .................
/SPS ...................
/X1 ......................
-1 ........................................................ Conductivity Converter
General
115V AC at 50/60 Hz
230 V AC at 50/60 Hz
100 V AC at 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
G1/2
1/2NPT
With screws for salt protection (*1)
Epoxy baked finish (*2)
Hood
Tag plate
Conduit Adapter
T02.EPS
Type
(*1) The SUS screws with teflon coating are used at the four corners of the cover.
(*2) The housing is coated with epoxy resin.
[ Style : S2 ]

IM 12D08N04-01E 3-1
3. Installation and Wiring
3. Installation and Wiring
3-1. Installation and dimensions
3-1-1. Installation site
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 20 meters. 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 transmitter 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 mm)

IM 12D08N04-01E
3-2
3. Installation and Wiring
184
144
72
20
144
220
23 112
Four M6 screws, 8 deep
80
80
36 36
36
38
ABC
DEF
Hood (optional)
Option code : /Hh
Grounding terminal
(M4 screw)
Unit : mm
Cable inlet port (21 dia. holes)
equivalent to DIN PG13.5 cable gland
A : For sensor cable
B : For output signal
C : Spare (can be used for contact input separately)
D : For contact output (S3 and S4)
E : For contact output (S1 and S2)
F : For power supply
Adaptor for conduit work
49
Adapter
G1/2 screw (/AFTG)
1/2 NPT screw (/ANSI)
Approx.
55
Unit : mm
Figure 3-1.Housing dimensions and layout of cable glands

IM 12D08N04-01E 3-3
3. Installation and Wiring
M6, 4 screw
100
178
137
+2
0
137
+2
0
12 max. (panel thickness)
23
Panel cutout dimensions
Unit : mm
Figure 3-2.Panel mounting diagram
188
174
50
200
100
M6, 4 screw
135 13
224
M6, 4 screw
200
35
15 70
100
10 mm dia. ,3 hole
dExample of bracket used for pipe mounting
Nominal 50 mm (OD 60.5 mm)
mounting pipe
dExample of bracket used for wall mounting
Unit : mm
Figure 3-3. Wall and pipe mounting diagram

IM 12D08N04-01E
3-4
3. Installation and Wiring
Output signal
(4 to 20mA DC, or
0 to 20mA DC)
Output signal
(4 to 20mA DC, or
0 to 20mA DC)
11
12
13
14
15
16
61
62
65
66
63
21
22
+
-
+
-mA 2
mA 1
31C
32NC
33NC
41C
42NC
43NC
L1
L2
G
S1
S2
S3
S4
51C
52NC
53NC
71C
72NC
73NC
Grounding
Power supply
SC402G
4-wire conductivity converter
Conductivity
sensor
Remote contact
input
*1
*2
*3
Relay settings S1
Relay settings S2
Relay settings S3
Relay settings S4
Note : External wiring connection terminal size is for f2 pin.
*1 : Always use a shielded cable with an O.D. of 6 to 12 mm
*2 : Be sure to ground the converter case grounding terminal
(grounding resistance of 100 Vor less)
*3 : Always use a cable with an O.D. 6 to 12 mm. Choose the terminal combination
of C and NC or card NO of Contact signal S1 to S4 for your purpose.
1
2
3*3
*3
?Upper and lower
linit alarms
?HOLD
etc.
?HOLD
?Upper and lower
linit alarms
etc.
?Fail alarms
etc.
*4
*4 : For sensor wiring , refer to Fig.3-9 to 3-10.
Figure 3-4. Wiring Diagram

IM 12D08N04-01E 3-5
3. Installation and Wiring
3-2. Preparation
Refer to figure 3-5. The relay contact terminals and power supply connections are under
the screening (shielding) plate. These should be connected first. Connect the sensor and
outputs 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 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 to
minimise noise pickup.
7. Connect the analog output(s) and the sensor input.
8. Use the front three glands for analog output, sensor input and contact input (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.
Contact
(S3,S4,FAIL)
output
cables
Sensor
cables
Contact
(S1, S2)
output
cables
Analog
output
cables
Power
cable Contact input
Suitable for cables with an outside diameter between 6 to 12 mm.
High voltage section
Figure 3-5. Glands to be used for cabling

IM 12D08N04-01E
3-6
3. Installation and Wiring
REAR GLANDS
Output
signals
Sensor
S1
S2
Power
S3
FRONT GLANDS
Range switch S4/FAIL
Contact
output
Contact
output
Figure 3-6. System configuration

IM 12D08N04-01E 3-7
3. Installation and Wiring
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 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 in-
stalled. 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 IEC127.
Fuse ratings are 230 VAC - 50 mA; 100 VAC - 100 mA; 115 VAC - 100 mA.
The internal fuse is located next to the power terminals (in the lower righthand corner).
3-3-2. Access to terminal and cable entry
Terminals 1, 2 and 3 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).
131415 11 1216
22 21 63 66 65 62 61
SENSOR mA OUTPUT
CONT
SCREEN
mA2 mA1
Sensor Inputs
Contact
Input mA Outputs
71
S4 S3 S2 S1
C NC NO
72 73 51 52 53 41 43 31 3342 32
250 VAC
5 A
100 VA
250 VDC
5 A
50 W
FUSE
100
115
230 250VAC; T
312
GL1L2
C NC NO C NC NO C NC NO
VAC
VAC
VAC
100 mA
100 mA
50 mA
Relay Contacts Power Supply
High voltage compartment
Figure 3-7. Input and output connections