Sensorex CX100 User manual

Loop-Powered 4-20mA
Conductivity Transmitter
CX100
PRODUCT INSTRUCTION MANUAL

1
Preface
This manual s erves to explain the use of the CX100 transmitter. It functions
in two ways, firstly as a step by step guide to help you to operate the
transmitter. Secondly, it serves as a handy reference guide. It is written to cover as
many anticipated applications of the trans mitter as possible. Please contact Sensorex
if you have any questions about the use of this transmitter.
Sensorex will not accept any responsibility for damage or malfunction to the
transmitter caused by improper use.
The information presented in this ma nual is subject to change without notice as
improvements are made, and does not re present a commitment on the part of
Sensorex.
Copyright © 2012
All rights reserved

2
TABLE OF CONTENTS
1 INTRODUCTION ...................................................................................3
2 PREPARATION ....................................................................................4
2.1 POWER SUPPLY REQUIREMENTS (SL2 POSITION) ...........................................5
2.2 CONNECTING THE ELECTRODE AND TEMPERATURE SENSOR (SL1 POSITION) ....5
3 INSTALLATION .................................................................................... 7
3.1 MECHANICAL DIMENSIONS ............................................................................7
3.2 WALL MOUNT ..............................................................................................7
3.3 PANEL MOUNT ............................................................................................8
4 DISPLAY AND KEYPAD FUNCTIONS .............................................. 9
4.1 DISPLAY ................................................................................................... 9
4.2 KEYPAD .................................................................................................... 10
5 CALIBRATION .................................................................................... 11
5.1 IMPORTANT INFORMATION ON TRANSMITTER CALIBRATION ............................. 11
5.2 TEMPERATURE CALIBRATION ...................................................................... 13
5.3 CONDUCTIVITY CALIBRATION ...................................................................... 14
6 ADVANCED SETUP FUNCTIONS ..................................................... 15
6.1 RANGE AND ZOOMING SELECTION SETTING .................................................. 15
6.2 TEMPERATURE COMPENSATION SETTING ..................................................... 17
6.3 HOLD CURRENT SETTING .......................................................................... 20
6.4 OUT-OF-RANGE CURRENT SETTING ............................................................ 20
6.5 TEMPERATURE COEFFICIENT AND NORMALIZATION TEMPERATURE SETTING .... 21
6.6 CELL CONSTANT SETTING .......................................................................... 22
6.7 LINE RESISTANCE SETTING ......................................................................... 22
6.8 VIEWING CALIBRATION POINT...................................................................... 23
6.9 VIEWING THE ELECTRODE DATA .................................................................. 23
6.10 RESET FUNCTION ...................................................................................... 24
7 FACTORY DEFAULT SETTINGS ...................................................... 25
8 TROUBLE SHOOTING GUIDE ........................................................... 26
9 SPECIFICATIONS .............................................................................. 27
10 WARRANTY ........................................................................................ 28
11 RETURN OF ITEMS ............................................................................ 28

3
1 INTRODUCTION
Thank you for selecting an CX100 2-Wire Conductivity Transmitter. This isolated
output 4-20mA transmitter is a stur dy microprocessor-based instrument that
measures conductivity and temperature and transmits its output via the 2-wire
power supply loop.
This transmitter has many user-friendly features – all of which are completely
accessible through the water-resistant membrane keypad. Your transmitter includes
an instruction manual and a warranty card.
Please read this manual thoroughly before operating your transmitter.
Conductivity ZLUHTransmitter
.
ATC
1413
μ S
.

4
2 PREPARATION
Remove screws from the four corners at the back of the Transmitter, and remove
back cover.
Connectors should be exposed as follows:
NC
NC
NC
Figure 1 – Connection Guide
All wiring is done on 2 detachable connectors: –
1. 9-pin connector (located on SL1 position) for Conductivity electrode and
temperature sensor
2. 3-pin connector (located on SL2 position) for power supply.
Using a suitable screwdriver, loosen screws from top of connector.
When inserting the wires, always hold connector with top screws facing up.

5
2.1 Power Supply Requirements (SL2 Position)
The CX100 Conductivity transmitter requires a 1 2 to 2 4V DC power supply. Other
Transmitters and/or a chart recorder may be connected in the loop.
1. Insert positive loop wire from power supply to pin 1, tighten screw.
2. Insert negative loop wire to pin 2, tighten screw. This wire may be linked to
a chart recorder or to negative terminal of power supply.
2.2 Connecting the Electrode and Temperature Sensor (SL1
Position)
2.2.1 To connect the Conductivity electrode:
The CX100 conductivity transmitter accepts any industrial electrodes for conductivity
measurements and they are usually offered with bare wires.
1. For Sensorex conductivity electrodes (except model CS8000TC/PT1) wiring
is as follows: Red (connect to 3(cond L) on SL1), Black (connect to 4 (cond
H) of SL1), See section 2.22 for temperature wire connection
CX100
Power
Supply
Chart
Recorder
1
2
2. For Sensorex model CS8000TC/PT1 cable assembly S855 is used.
Wiring wiring is as follows: Coaxial Center wire (connect to 3(cond L) on
SL1), Coaxial braid (connect to 4 (cond H) of SL1), See section 2.22 for
temperature wire connection

6
2.2.2 To connect ATC temperature sensor:
For Automatic Temperature Compensated (ATC) Conductivity readings, an in-built
temperature sensor is usually integrated in the in dustrial conductivity electrodes.
Otherwise, a separate 100Ω Pt RTD temperature probe can be used.
3 wire temperature sensor (not Sensorex)
1. Insert the Pt100 input wire to pin 5 of SL1 connector. Tighten the screw.
2. Insert the Pt100 sense wire to pin 6 of SL1 connector. Tighten the screw.
3. Insert the Pt100 return wire and the shield wire to pin 7 of SL1 connector.
Tighten the screw.
2 wire temperature sensor(Sensorex All models except CS8000TC)
1. Take a small length of wire and short pins 5 and 6 of SL1 connector. Insert
Pt 100 sense wire (green) into pin 6 of SL1 connector and tighten the
screws.
2. Insert Pt 10 0 return wire (white) and the s hield wire to pin 7 of SL1
connector. Tighten the screw.
IMPORTANT: It is necessary to connect the SHIELD wire to the pin 7 as stated
above to eliminate possible oscillation of the conductivity and/or temperature
reading due to electrical noise or interference.
Ensure that no bare wires are exposed and all screws are tightened for proper
contact.
2 wire temperature sensor(Sensorex model CS8000TC)
1. Take a small length of wire and short pins 5 and 6 of SL1 connector. Insert
Pt 100 sense wire (red) into pin 6 of SL1 connector and tighten the screws.
Insert Pt 10 0 return wire (black) and the s hield wire to pin 7 of SL1
connector. Tighten the screw.

7
3 INSTALLATION
3.1 Mechanical Dimensions
2-wire Conductivity Transmitter
3.2 Wall Mount
mm mm
mm
mm
3.76 in.
5.06 in.
2.60 in.
3.74 in.

8
3.3 Panel Mount
1. Prepare panel cut-out of
92.0 mm by 92.0 mm
2. Remove back cover of
transmitter and slide it
through panel cut-out
Panel (side)
3. Attach lugs to both
sides of transmitter
4. Thread rods through
lugs until transmitter
is held in place against
panel
(3.62 x 3.62 in.)

9
4 DISPLAY AND KEYPAD FUNCTIONS
4.1 Display
The LCD has a primary and secondary display.
•The primary display shows the measured conductivity value.
•The secondary display shows the measured temperature. In C alibration
mode, measured conductivity values are displayed here.
SETUP MEAS CAL
ON
°C
-.8.8.8
-1.8.8.8
ATC
mS
R.
ERR
123 4
5
6
7
8
9
10
11
12
13
15
16
14
μ S
%
K=
Primary Display
(Upper Display)
Secondary Display
(Lower Display)
1. SETUP - Setup mode
indicator
5. % - Temperature
Coefficient
indicator
9. ATC - Automatic Temp.
Compensation 13. - Calibration
standard indicator
2. MEAS - Measurement
mode indicator
6. mS - Milli Siemens
indicator
10. K = - Cell Constant
indicator.
14. ON /OFF– READY set
up enable/disable
indicator.
3. CAL - Calibration mode
indicator 7. µS - Micro Siemens
indicator
11. ERR – Wrong key
press error
indicator
15. HOLD – Hold indicator
4. R. – Line Resistance in
Ohms
8. °C - Temperature
indicator 12. - Electrode indicator
16. READY – Ready
indicator

10
4.2 Keypad
.
ATC
1413
μ S
MEAS
°C
READY
.
ATC
1413
μ S
The four-button keypad allows easy and quick operations of the Transmitter.
Key Function
CAL Brings you directly into the Calibration mode.
If you were in Conductivity Measurement mode, press CAL to enter
Conductivity Calibration mode.
▲ / ▼ To scroll through the various submenus
To increment/decrement values or toggle between options (in the
SETUP/CAL modes)
When pressed together, serves as escape function to return to MEAS mode
from any point (CAL or SETUP modes).
ENT To confirm your calibration values in Calibration mode.
To confirm selections in SETUP mode.
While in MEAS mode, pressing ENT takes you directly to SETUP submenu
NOTE: Error indicator ‘ERR’ will be displayed if an i nvalid key is pressed during a
particular operation.
.
ATC
1413
μ S
MEAS
°C
READY
.
ATC
1413
μ S
The four-button keypad allows easy and quick operations of the Transmitter.
Key Function
.
ATC
1413
μ S
MEAS
°C
READY
.
ATC
1413
μ S
The four-button keypad allows easy and quick operations of the Transmitter.
Key Function
.
ATC
1413
μ S
MEAS
°C
READY
.
ATC
1413
μ S
The four-button keypad allows easy and quick operations of the Transmitter.
Key Function
.
ATC
1413
μ S
MEAS
°C
READY
.
ATC
1413
μ S
The four-button keypad allows easy and quick operations of the Transmitter.
Key Function
.
ATC
1413
μ S
MEAS
°C
READY
.
ATC
1413
μ S
The four-button keypad allows easy and quick operations of the Transmitter.
Key Function
.
ATC
1413
μ S
MEAS
°C
READY
.
ATC
1413
μ S
The four-button keypad allows easy and quick operations of the Transmitter.
Key Function
.
ATC
1413
μ S
MEAS
°C
READY
.
ATC
1413
μ S
The four-button keypad allows easy and quick operations of the Transmitter.
Key Function
.
ATC
1413
μ S
MEAS
°C
READY
.
ATC
1413
μ S
The four-button keypad allows easy and quick operations of the Transmitter.
Key Function
.
ATC
1413
μ S
MEAS
°C
READY
.
ATC
1413
μ S
The four-button keypad allows easy and quick operations of the Transmitter.
Key Function

11
5 CALIBRATION
5.1 Important Information on Transmitter Calibration
Calibration should be carried when you are using your transmitter with a new
electrode for the first time or when you suspect that the transmitter/electrode is out
of calibration. Your transmitter allo ws you to perform temperatur e calibration and
conductivity calibration.
As temperature readings affect the accuracy of conductivity measurements, it is
recommended that tempera ture calibration should be carried out only if the
temperature value displayed on the transmitter is different from that of a calibr ated
thermometer. A temperature offset calibration of ± 5 °C from the default r eading is
allowed. Once a temperatur e calibration is performed, conductivity calibration
should be carried out to ens ure the acc uracy of con ductivity measurements are
maintained.
Your transmitter has up to six selectable conductivity measuring ranges. The
selection for th e sixth range, range 6 ( 0.00 to 199.9 mS/cm), onl y appears in th e
Setup mode if the cell co nstant is sele cted to be K = 1.0 or K = 10 whereas range
1(0.00 to 19.99uS/cm), will only appear when cell constant is selected to be K = 0.1
or K = 1.0. Other wise, the selection will be limited to five ranges only.
You can only calibrate one point in the measuring range that you have selected for
your process application. You have to rec alibrate your transmitter every time you
change the measuring range since th e calibration data of your transmitter will be
erased every time a new measuring range is selected.
During conductivity calibration, the transmitter allows a calibration window of ± 40%
from the mea sured default reading of the calibration standard. The minimum
allowable calibration point is 10% of the full scale reading of the range selected.
For best resul ts, select a stand ard value close to the sample value you are
measuring. Alternatively use a calibration solution value that is a pproximately 2/3
the full-scale value of the measurement range you plan to use. The following table 1
lists the corresponding conductivity ranges. You should calibrate, in the range that
you have selected, using a solution that falls between the values in the
“recommended calibration solution range” column.

12
Table 1
Conductivity
Measuring Range
Recommended Calibration Solution
Range
0.00 Æ 19.99 μS 6.00 to 17.00 μS
0.0 Æ 199.9 μS 60.0 to 170.0 μS
0 Æ 1999 μS 600 to 1700 μS
0.00 Æ 10.00 mS 6.00 to 7.00 mS
0.00 Æ 19.99 mS 6.00 to 17.00 mS
0.0 Æ 199.9 mS 60.0 to 170.0 mS
To view current calibration point, see Section 6.8 - Viewing Calibration .
Do not reuse calibration solutions after calibration. Contaminants in the solution can
affect the calibration, and eventually the accuracy of the m easurements. Use fresh
calibration solution each time you calibrate your meter.
NOTE: Your transmitter is factory set to a temperature coefficient of 2.1% per °C.
For most applications this will provide good results. The factory default value
for normalization temperature is 25 °C. If you need to set a different
temperature coefficient or change the normalization temperature value, see
Section 6.5 - Temperature Coefficient and Normalization Temperature
Setting for further information.
NOTE: In the CAL mode, the 4/20 mA out put current will be autom atically held.
‘HOLD’ will be displayed on LCD. After calibration is performed and when the
transmitter is back to the measurement mode, the ‘HOLD’ is automatically released.
Please refer to section 6.3 for more details.

13
5.2 Temperature Calibration
You need to perform temperature calibration if your transmitter temperature reading
is inaccurate or if the transmitter’s cell constant setting is changed. It is because the
transmitter’s temperature offset calibration will be erased once a n ew cell constant
is selected.
It is important to ens ure that temperature calibration is c arried out first prior to
conductivity calibration since temperature readings affect the accurac y of
conductivity measurements. Your transmitter allows a one point temperature
calibration using reference of a thermometer known to be accurate. Please refer to
Section 6.2 - Temperature Compensation Setting for temperature calibration
procedure.

14
5.3 Conductivity Calibration
A 1-point Calibration is required for this transmitter. If
the calibration process is aborted, your transmitter
will revert to the previous calibration data.
1. Organize your calibration standard solution
in two beakers – one for rinsing and the
other for calibration. Prepare separate de-
ionized water for electrode rinsing.
2. Rinse the electrode in de-ionized water and
then rinse with the calibration standard.
3. Dip the electrode to the calibration standard
intended for calibration and swirl gently to
create a homogenous sample. Wait for the
reading to stabilize.
4. Press the CAL key to enter calibration
mode. The upper display will show the
measured reading based on the last
calibration setting whereas the lower display
will show the measured default reading of
the standard.
5. Use the ▲ or ▼ keys to adjust the upper
display to the calibration standard value.
Note: You can offset the conductivity reading within
± 40% from the default reading of the standard. The
minimum allowable calibration point is 10% of the full
scale reading of the range selected.
6. Press the ENTER key to confirm the calibration value and to return to the
measurement mode.
Note: To exit this program without confirming the calibration, press the ▲ and ▼
keys together (Escape).
Note: When there is a calibration error, th e buffer icon and ERR annunciator will
appear together with a blinking electrode icon. Press both ▲ and ▼ keys together
TWICE to return to the measurement mode.
HOLD
HOLD
MEAS
°C
1578
25.5
ATC
μ S
CAL
1578
1578
μ S
CAL
1413
1578
μ S

15
6 ADVANCED SETUP FUNCTIONS
The advanced setup m ode lets you customize your transmitter’s preferences and
defaults. This transmitter features d ifferent sub gro ups that organize all setup
parameters. The sub-groups are:
6.1 Range and Zooming Selection Setting
Your CX100 transmitter provides six selections of conductivity measurement
ranges to suit your process application needs. Zooming selection is available where
both the 4 mA and 2 0 mA output current c an be assigned to specific c onductivity
values for a more refined output.
From the measurement mode,
1. Press the E NT key to enter the setu p mode.
Transmitter displays ‘SEt rng’ indicating the
range setup mode.
2. Press the ENT key again. The display will show
the last set conductivity measurement range.
3. Use the ▲ or ▼ keys to scroll thro ugh the six
ranges and press the ENT key to s elect your
desired range. The transmitter will now switch to
the zooming selection and display the low zoom
value setup.
NOTE: Range 6 selection page will only appear in the
setup mode when the cell constant is selected as K =
1.0 or K = 10. Range 1 will only appear when cell
constant is selected as K =0.1 or K =1.0
SETUP
HOLD
SETUP
HOLD
19.99
1
Six Range selection
μ S

16
4. For zooming setting, use the ▲ or ▼ keys to set
the conductivity low zoom value for the 4 mA
current and press the ENT key to c onfirm. The
transmitter now displays the high zoom value
setup.
5. Use the ▲ or ▼ keys again to set the
conductivity high zoom va lue for the 20 mA
current and press the ENT key to co nfirm and
return to the range setup mode.
6. Press both ▲ and ▼ keys together to r eturn to
the measurement mode.
SETUP
HOLD
0.00
L
SETUP
HOLD
19.99
Hi
μ S
μ S

17
6.2 Temperature Compensation Setting
Conductivity readings are affected by temperature. Under varying temperature
conditions, use ATC to compens ate for th e conductivity values. If temperature of
sample is constant, and a temperature sensor/probe is not available, Manual
Temperature Compensation can be utilized.
6.2.1 Automatic Temperature Compensation
For automatic temperature compensation (ATC) selection, connect the ATC sensor
to the transmitter, as described in Section 2.2.2.
1. Press the ENT key to enter the setup mode. Use the ▲ or ▼ keys to scroll
through the sub-menus till LCD displays ‘SEt oC’.
2. Press the ENT key to enter the temperature compensation mode. Display
shows ‘AtC On’ or ‘AtC Off’. Use S or T keys to select ‘AtC On’ and
then press the ENT key.
3. Dip ATC sensor into a s olution of known temperature (i.e. a temper ature
bath). Allow time for temperature sens or to acclimatiz e with surrounding
bath temperature.
4. Use S or T keys to adjust the displayed reading to the correct
temperature value according to the t emperature bath. Maximum
adjustments allowed is ± 5 oC (± 9 oF) from the default reading.
5. Once you have adjusted to t he correct temperature value, press the ENT
key to confirm the setting.
6. Press S and T keys together to return to the measurement mode.
The ATC indicator will light up on the LCD.
NOTE: If y ou are using a te mperature sensor, the senso r must be sub mersed in
the liquid you are measuring.

18
6.2.2 Manual Temperature Compensation
For manual temperature compensation you can set t he process and calibration
temperatures. This allows calibration at a temperature other than the process
temperature. Example: setting a cal ibration temperature of 25°C lets you calibrate
using standard solutions at 25°C, even if your process temperature is different from
25°C.
From the measurement mode,
1. Press the ENT key and use ▲ or ▼ keys to select ‘SEt oC’.
2. Press the ENT key to enter the temperature compensation mode. Display
shows ‘AtC On’ or ‘AtC Off’. Use S or T keys to select ‘ AtC Off’ and
then press the ENT key.
3. The primary display will show temperature (default is 25.0), and the
secondary display shows ‘P °C’’. T his is the p age for setting th e
temperature of your process or sample by using an accurate thermometer
as reference.
4. Use ▲ or ▼ keys to set the transmitter to the temperature of your process
or sample. Press the ENT key.
5. The primary display shows temperature (default is 25.0), and seco ndary
display shows ‘C °C’. This is the pa ge for setting the tem perature of your
calibration solutions.
6. Use ▲ or ▼ keys to set the transmitter to the temperature of your
calibration solutions. Press the ENT key.
7. Press S and T keys together, to return to the measurement mode.
The transmitter will now compensate conductivity readings for the manually set
temperature (values taken from P °C’).

19
SETUP
HOLD
SETUP
HOLD
SETUP
HOLD
°C
.
.
ATC
SETUP
HOLD
SETUP
HOLD
.
SETUP
HOLD
.
Temperature Compensation Setting Chart – CX100 Transmitter