LaMotte CON 6 PLUS User manual

1

PREFACE
This manual serves to explain the use of the Conductivity and TDS
handheld meters. The models covered are the CON 6 PLUS and TDS 6
PLUS.
This manual functions in two ways: first as a step by step guide to
operating the meter; second, as a handy reference guide.
This manual is written to cover as many anticipated applications of
the Conductivity and TDS handheld meters as possible. If there are
questions about the use of this meter contact the LaMotte Tech Service
Department.
LaMotte Company will not accept any responsibility for damage or
malfunction to the meter caused by improper use of the instrument.
The information presented in this manual is subject to change without
notice as improvements are made, and does not represent a commitment
on the part of LaMotte Company.
*WARNING: Reagents marked with an * are considered to be potential
health hazards. To view or print a Safety Data Sheet (SDS) for these
reagents go to www.lamotte.com. Search for the four digit reagent code
number listed on the reagent label, in the contents list or in the test
procedures. Omit any letter that follows or precedes the four digit code
number. For example, if the code is 4450WT-H, search 4450. To obtain a
printed copy, contact LaMotte by email, phone or fax.
Emergency information for all LaMotte reagents is available from Chem-
Tel: (US, 1-800-255-3924) (International, call collect, 813-248-0585).
WARNING! This set contains chemicals that
may be harmful if misused. Read cautions on
individual containers carefully. Not to be used by
children except under adult supervision.

TABLE OF CONTENTS
1. INTRODUCTION 5
2. GETTING STARTED 6
2.1 Description of Keypad Functions 6
2.2 Description of LCD Annunciators 7
2.3 Inserting & Removing the Rubber Boot/Stand 8
2.4 Inserting New Batteries 8
2.5 Battery Replacement 9
2.6 Electrode Information 9
2.7 Connecting the Probe 10
2.8 Switching the Meter On 11
2.9 Changing Mode 12
3. CALIBRATION 13
3.1 Important Information on Meter Calibration 13
3.2 Preparing the Meter for Calibration 14
3.3 Selection of Auto or Manual Calibration ( CON 6 PLUS) 14
3.4 Using Automatic Calibration ( CON 6 PLUS) 15
3.5 Manual Calibration 16
3.6 Temperature Calibration 17
4. MEASUREMENT 18
4.1 With Automatic Temperature Compensation (ATC) 18
4.2 Without ATC (Manual Temperature Compensation) 18
4.3 Taking Measurements 18
4.4 Using Manual Ranging Function
( CON 6 PLUS, TDS 6 PLUS) 19
4.5 HOLD Function 20
5. ADVANCED SETUP FUNCTIONS 20
5.1 Advanced Setup Overview 20
5.2 Select Cell Constant ( CON 6 PLUS, TDS 6 PLUS ) 22
5.3 Automatic Calibration ( CON 6 PLUS only) 22
5.4 Setting the TDS Factor ( TDS 6 PLUS only) 23
5.5 Temperature Coecient 23
5.6 Normalization Temperature 24
5.7 Single-Point Calibration ( CON 6 PLUS, TDS 6 PLUS ) 24
5.8 Restore Factory Default Values 25
6. PROBE CARE AND MAINTENANCE 25
7. TROUBLESHOOTING 26
8. SPECIFICATIONS / FEATURES 27
9. CONDUCTIVITY THEORY 28
10. CALIBRATION TIPS 31
11. CALCULATING TDS CONVERSION FACTOR 31
12. CALCULATING TEMPERATURE COEFFICIENTS 32
13. REPLACEMENT PARTS AND ACCESSORIES 33
14. WARRANTY 33
15. REPAIRS 34

5
1. INTRODUCTION
The CON 6 PLUS and TDS 6 PLUS microprocessor-based handheld
meters are economical and easy to use. They have a large custom LCD
(Liquid Crystal Display) for clear and easy reading.
The CON 6 PLUS measures conductivity (S/cm or mS/cm) and
temperature (°C) while the TDS 6 PLUS measures total dissolved
solids (TDS) in parts per million (ppm) or parts per thousand (ppt) and
temperature (°C). Each meter measures up to 5 dierent ranges and will
automatically switch to appropriate measuring range.
The meters include a probe (cell constant K = 1.0) with built-in
temperature sensor, rubber boot, 4 alkaline “AAA” batteries and
instruction manual. For additional information, see Section 13 —
REPLACEMENT PARTS AND ACCESSORIES.
Read this manual thoroughly before operating the meter.

6
2. GETTING STARTED
2.1 Description of Keypad Functions
The meter has 6 keys on the splash-proof keypad. Some buttons have
multiple functions depending on the mode of operation.
ON/OFF Powers meter on and o. Meter starts up in the
measurement mode that was last used.
CAL Enters into calibration mode. Pressing while in calibration
mode will abort calibration without confirming value.
MODE Selects desired measurement mode. When pressed
simultaneously with ON/OFF, it will take proceed the
SETUP mode. See ADVANCED SETUP section for more
information.
HOLD Freezes measured reading. Press again to resume live
reading.
ENTER Confirms calibration value in calibration mode and
confirm selections in SETUP mode.
Increments values during calibration mode or scroll
through SETUP. Activates manual ranging function during
conductivity / TDS measurement.
Decrements values during calibration mode.

7
2.2 Description of LCD Annunciators
The meter has a large custom LCD that consists of 4-digit segments plus
annunciators for uS/mS (CON 6 PLUS), ppm/ppt (TDS 6 PLUS), and °C
(temperature).
1. Primary display
2. Parts per million (ppm) or parts per thousand (ppt)
(TDS 6 PLUS)
3. Millisiemens/cm (mS) or microsiemens/cm (S)
indicator (CON 6 PLUS)
4. Temperature indicator
5. Percentage indicator for temperature coecient
6. “LO” = low battery condition
7. “HO” = HOLD function is activated and reading is
frozen
pptm
HO LO %
m
S
μ
1
2
3
4
5
67
C°

8
2.3 Inserting & Removing the Rubber Boot/Stand
1. To remove the meter from the rubber boot, push out the bottom
edge of the meter until it is completely out of the boot. Ensure
that the probe cables are not connected. Figure 1.
2. To insert the meter into the rubber boot, slide in the top of the
meter before pushing the bottom edge of the meter down to set it
into position. Lift up the stand at the back of meter for bench top
applications. Figure 2.
2.4 Inserting New Batteries
The battery compartment is found at the back of the instrument. To open
the battery compartment, push the cover in the direction of the arrow
and lift up. Note the polarity of the batteries before inserting them into
position. After the batteries have been replaced, reposition the cover and
press down until it locks.
Figure 1 Figure 2

9
2.5 Battery Replacement
The “LO” annunciator on the LCD alerts when battery power is running
low.
Caution: Power othe meter before changing battery.
2.6 Electrode Information
The meter includes a probe with a BNC connector
having a nominal cell constant of k = 1.0, and a built-in
temperature sensor. The Ultem-body housing has good
chemical resistant properties. The probe design oers fast
temperature response and reduces air entrapment, ensuring
accurate, repeatable, and stable readings.
The wettable materials of the probe include:
1. Polyetherimide (Ultem) – protective probe guard
2. Polybutylterphalate (Valox) – sensor housing
3. Stainless Steel (SS 304) – 2 steel bands
The protective probe guard can be removed temporarily
for maintenance but must be reattached before
measurement and calibration. Erroneous results will occur
during calibration and measurement if the probe guard is
not used.
Always immerse the probe beyond upper steel band for
best results. Use the fill line on the outside of the probe
guard for reference.
“LO” Battery Condition
LO
S
μ

10
1. DO NOT perform
calibrations or
measurements without the
protective probe guard in
place.
2. Immersion above the
protective guard is not
recommended. The cable
can be submerged briefly
but is not designed for
continuous immersion.
See “Probe Care and Maintenance”
for more information.
2.7 Connecting the Probe
1. To connect the probe, align the connector slots with the posts of
the meter socket and rotate the connector clockwise until it locks.
2. To remove the probe, rotate the connector in anti-clockwise
direction until it unlocks, and slide the connector othe socket.
3. Insert the mini phono jack of the temperature sensor into the
socket on the meter as shown below.
2.5 mm mini phono
jack for
temperature sensor
BNC
connector for
probe

11
2.8 Switching the Meter On
Press ON/OFF to power up the meter. The meter will cycle through
various setup parameters when switched on.
1. The first screen will show the model [Con6] [tdS6].
2. The second screen will show the nominal cell constant value.
The CON 6 PLUS and TDS 6 PLUS meters can accept
electrodes with k = 0.1, 1.0 or 10.0 nominal cell constants.
Default value is k = 1.0 [C 1.0].
See Section 5.2 Advanced Setup to modify.
3. The third screen will show the Normalization Temperature which
can be set to 25 °C or 20 °C. The default value is 25 °C [t 25.0 °C].
See Section 5.6 Advanced Setup to modify.
4. The fourth screen will show the Temperature Coecient which
can be set from 0.0 to 3.0 % per °C. Default value is 2.1 %/°C
[t 2.1%].
See Section 5.5 Advanced Setup to modify.
5. All LCD segments will light for 2 seconds before entering the
measurement mode. Note: The meter will use the measurement
mode that was in use when it was powered o.
CON 6 PLUS
Measurement Mode
m
S
μ
C°
%
pptmV
pH %MINMAXLOHO
F
C° °
m
S
μ
S
μ
ON
OFF

12
TDS 6 PLUS
2.9 Changing the Mode
To switch between conductivity or TDS measurement mode and
temperature measurement mode, press the MODE key.
The annunciator will indicate the measurement mode.
Measurement Mode
C°
%
ON
OFF
ppm
pptmV
pH %MINMAXLOHO
F
C° °
m
S
μ
pptm
Annunciator
MODE
S
μ
C°

13
3. CALIBRATION
3.1 Important Information on Meter Calibration
The CON 6 PLUS and TDS 6 PLUS have five measuring ranges listed
below. Each range can be calibrated to one point per range (five total
points if each range is calibrated). Calibration is recommended for each
range that will be utilized.
CON 6
PLUS Conductivity Range
Recommended Calibration
Solution Range
0.00 20.00 S/cm 6.00 to 17.00 S/cm
0.0 200.0 S/cm 60.0 to 170.0 S/cm
0 2000 S/cm 600 to 1700 S/cm
0.00 20.00 mS/cm 6.00 to 17.00 mS/cm
0.0 200.0 mS/cm 60.0 to 170.0 mS/cm
TDS 6
PLUS TDS Range
Recommended Calibration
Solution Range
0.00 10.00 ppm 3.00 to 8.50 ppm
10.0 100.0 ppm 30.0 to 85.0 ppm
100 1000 ppm 300 to 850 ppm
1.00 10.00 ppt 3.00 to 8.50 ppt
10.0 200 ppt 30.0 to 170 ppt
New calibrations will replace old calibrations on a per range basis. For
example, if the meter has been calibrated with 1413 S/cm (0 to 2000
S/cm range) and a calibration is performed with 1500 S/cm (also 0 to
2000 S/cm range), the meter will replace the 1413 S/cm calibration in
that range. The meter will retain all calibration data in other ranges.
When the probe is replaced, it is best to clear all calibration data. To
erase all calibration data completely, see Section 5.8 Restore Factory
Default Values.

14
3.2 Preparing the Meter for Calibration
For the best results, select a standard with a concentration close to the
concentration of the sample being measured. Alternatively, a calibration
standard with a concentration that is approximately 2/3 the full-scale
of the measurement range. For example, in the 0 to 2000 S/cm
conductivity range, use a 1413 S/cm standard for calibration.
Use fresh calibration standards. Reuse of standard solutions may impair
the calibration and the accuracy of measurements. Store solutions in a
dry, dark, cool environment and limit exposure to air.
Rinse or immerse the probe in clear water before calibration and between
samples. Deionized water is ideal.
3.3 Selection of Auto or Manual Calibration (CON 6 PLUS)
The CON 6 PLUS is capable of automatic or manual calibration. The
factory default setting is automatic.
In the automatic calibration mode, the CON 6 PLUS will automatically
select one of four calibration standard values (see below) depending on
the range and normalization temperature being used.
Automatic calibration is useful when all of the calibration standards
fall into one of the groups listed below. For example, if the 1413 S/
cm standard reads as 1400 S/cm during calibration, press “ENTER” to
accept this value as 1413 S/cm using the automatic mode. In manual
mode, the increment button would have had to be pressed 13 times to
adjust the value to 1413 S/cm to before pressing “ENTER”.
Normalization
Temperature
Calibration Standards (Range)
25 °C
1. 84 S/cm (for 0 – 200 S/cm)
2. 1413 S/cm (for 0 – 2000 S/cm)
3. 12.88 mS/cm (for 0.00 – 20.00 mS/cm)
4. 111.8 mS/cm (for 0.0 – 200.0 mS/cm)
20 °C
1. 76 S/cm (for 0 – 200 S/cm)
2. 1278 S/cm (for 0 – 2000 S/cm)
3. 11.67 mS/cm (for 0.00 – 20.00 mS/cm)
4. 102.1 mS/cm (for 0.0 – 200.0 mS/cm)
Table 1: Conductivity Calibration Standards for Auto Calibrations
If a calibration standard is used that is not listed above, select manual
calibration.

15
See Section 5.3 Advanced Setup to modify automatic or manual
calibration.
3.4 Using Automatic Calibration (CON 6 PLUS)
In Automatic Calibration mode, the CON 6 PLUS can accept up to 4
calibration points with a maximum of 1 point per measurement range.
Note: Values in the 0.00 to 20.00 S/cm range cannot be calibrated in
Auto Calibration mode.
1. If necessary, press the MODE key to
select the conductivity mode.
2. Rinse the probe with deionized water
or a rinse solution. Rinse with a small
amount of calibration standard.
NOTE: For Automatic Calibration one of the
calibration standards listed in Table 1 must be
used.
3. Dip the probe into the calibration
standard. Stir gently with the probe to
create a homogeneous sample. Allow
time for the reading to stabilize.
4. Press the CAL key to enter the
conductivity calibration mode. The
[CA] indicator will appear briefly, and
then a value will appear flashing.
NOTE: To exit calibration without
confirmation, press CAL to return to the
measurement mode.
5. When the value is stable, press
ENTER. The calibration standard
value will appear for 3 seconds. If the
calibration is successfully performed,
[donE] will be displayed briefly before
meter returns to the measurement
mode.
6. Repeat steps 1-5 as needed with
additional calibration standards.
NOTES:
• To protect from erroneous calibrations, the allowable tolerance
is ±40% of the factory default value. If a calibration is attempted
with standards that fall outside of the tolerance range, the error
mS
mS
mS
mS
CAL
HOLD
ENTER
Measurement Mode

16
message “Err 1” will be indicated and the meter will return to
the measurement mode. For example, a 40% tolerance of a 1413
S/cm standard is 848 S/cm to 1978 S/cm.
• If the measured temperature (°C) of the calibration solution is
below 0 °C or above 50 °C, the error message “Err 2” will be
indicated and the meter will return to the measurement mode.
• Low conductivity standard solutions (less than 20 S/cm)
are unstable and are very temperature dependent. As a result,
reproducible calibration results are challenging in the lowest
measurement range (0.00 to 20.0 S/cm).
3.5 Manual Calibration
In Manual Calibration mode, the selection of conductivity calibration
standards is not limited to those listed previously in Table 1. This
example shows a manual calibration sequence using a 12.00 mS/cm
conductivity calibration standard.
1. If necessary, press the MODE key to select the conductivity
mode.
2. Rinse the probe thoroughly with
deionized water or a rinse solution.
Rinse with a small amount of calibration
standard.
3. Dip the probe into the calibration
standard. Stir gently with the probe to
create a homogeneous sample. Allow
time for the reading to stabilize.
4. Press CAL to enter the conductivity
calibration mode. The [CA] indicator
will appear briefly, and then a value will
appear flashing.
NOTE: To exit calibration without confirmation,
press CAL to return to the measurement mode.
5. When the value is stable, press or
to adjust the value to match the
calibration standard.
6. Press ENTER to confirm the adjusted
value. [CO] will appear briefly indicating
that the calibration was successful. The
meter will return to measurement mode.
7. Repeat steps 1-6 as needed with
additional calibration standards.
mS
mS
mS
mS
CAL
HOLD
ENTER
Measurement Mode

17
3.6 Temperature Calibration
The probe includes a built-in temperature sensor that is factory calibrated
with the meter. Perform the temperature calibration only if it is suspected
that temperature errors may have occurred over time or when the probe is
replaced.
The temperature reading can be oset up to ±5 °C from the original
(default) reading.
1. Connect the mini phono jack of the temperature sensor to the
meter. See Section 2.7.
2. If necessary, press MODE to select the
temperature measurement mode.
3. Press CAL to initiate the temperature
calibration. “CA” will appear briefly then
a temperature value will start flashing.
4. Dip the probe into a solution with a
known temperature (for example, a
temperature bath). Stir gently with the
probe. Allow time for the temperature to
stabilize.
5. When the value is stable, press or
to adjust the value to the solution
temperature.
6. Press ENTER to confirm the adjusted
value. [CO] will appear briefly indicating
that the calibration was successful. The
meter will return to the measurement
mode.
NOTE: To exit calibration without confirmation,
press CAL to return to the measurement mode.
C°
C°
C°
HOLD
ENTER
°C
CAL

18
4. MEASUREMENT
The meter is capable of taking measurements that incorporate
temperature measurements automatically (most common) or using a
temperature which is input manually (rare).
4.1 With Automatic Temperature Compensation (ATC)
To compensate the reading using temperature values as measured by
the electrode, attach the phono jack of the temperature sensor to the
meter. The measured reading will be automatically compensated to the
specified normalization temperature (either 20 °C or 25 °C). The rate of
compensation which is applied is the Temperature Coecient.
See Section 5.5 – Temperature Coefficient.
See Section 5.6 – Normalization Temperature.
4.2 Without ATC (Manual Temperature Compensation)
Manual temperature compensation will be applied after manually
entering the temperature value into the meter. The meter will compensate
from this fixed value to the normalization temperature. Any temperature
can be used between 0 and 50 °C. The default value is 25 °C.
To activate the manual temperature compensation, unplug the mini phono
jack of the temperature sensor from the meter and follow the steps 2 thru
6 of Temperature Calibration.
See Section 3.6 – Temperature Calibration.
4.3 Taking Measurements
1. Rinse the probe with deionized or distilled water before use to
remove any impurities. Shake or air dry. To avoid contamination
or sample dilution, rinse the probe with a small volume of the
sample.
2. Dip the probe into the sample. Stir the sample gently with the
probe.
3. Allow time for the reading to stabilize. Note the reading on the
display.
NOTE:
• The protective probe guard must be attached during
measurement. Erroneous results will occur while the probe guard
is removed.

19
• Always immerse the probe beyond upper steel band for best
results. Use the fill line on the outside of the probe guard for
reference.
4.4 Using the Manual Ranging Function
By default the meter has auto-ranging ability and automatically selects
the range in which the readings appear.
Alternatively, to override the auto-ranging function, a specific range can
be manually selected by pressing successively for each measurement
range. The five ranges are:
Conductivity
Range ( CON 6 PLUS)
TDS Range ( TDS 6 PLUS)
(using 0.5 TDS factor)
0 – 20.00 S/cm 0 – 10.00 ppm
0 – 200.0 S/cm 0 – 100.0 ppm
0 – 2000 S/cm 0 – 1000 ppm
0 – 20.00 mS/cm 0 – 10.00 ppt
0 – 200.0 mS/cm 0 – 100 ppt
NOTE:
• If the value of the solution that is being measured is higher than
the range selected, [Or] (over range) will appear. Press to
select a measurable range.
• The meter will reset to the Auto-ranging function when the meter
is turned o.
S
μ
mSmS
Auto-ranging Manual ranging: 0 - 20.00 uS/cm Manual ranging: 0 - 200.0 uS/cm
Manual ranging: 0 - 2000 uS/cmManual ranging: 0 - 20.00 mS/cmManual ranging: 0 - 200.0 mS/cm
S
μS
μ
S
μ

20
4.5 HOLD Function
For prolonged viewing of a reading, press
HOLD while in measurement mode to freeze
the display.
1. To hold a measurement, press HOLD
while in measurement mode. [HO] will
appear on the display.
2. To release the held value, press
HOLD again. [HO] will disappear and
measurement will resume.
NOTE:
• The meter will shut oautomatically 20 minutes after the last
key press.
• If the meter is shut oeither automatically or manually, the
HOLD value will be lost.
5. ADVANCED SETUP FUNCTIONS
5.1 Advanced Setup Overview
Advanced setup allows customization settings such as; selecting
the electrode cell constant, normalization temperature, temperature
coecient, TDS factor (TDS 6 PLUS), automatic or manual calibration
(CON 6 PLUS), single-point or multi-point calibrations ( CON 6 PLUS
and TDS 6 PLUS), and to reset meter to factory default.
To enter advanced setup mode:
1. Switch othe meter.
2. Press MODE and then ON, holding both keys for 2 seconds.
Release the ON key before releasing the MODE key.
3. If successful, [StUP] will appear briefly followed by [CELC].
4. Press or to select the desired advanced setup function.
S
μ
S
μ
HOLD
ENTER
HO