Mettler Toledo Thornton 2000 Instruction Manual

Part No. 84401

2000 Two-Channel Instrument

for pH, ORP, Conductivity, Resistivity,

Dissolved Oxygen, Dissolved Ozone

Instruction Manual

IMPORTANT SAFETY INFORMATION

• Follow all warnings, cautions, and instructions indicated on and supplied with this product.

• Install equipment as specified in this instruction manual. Follow appropriate local and national

codes.

• Use only factory documented components for repair. Tampering or unauthorized substitution of
parts and procedures can affect the performance and cause unsafe operation of your process.

• Protective covers must be in place unless qualified personnel are performing maintenance.

• If this equipment is used in a manner not specified by the manufacturer, the protection provided by

it against hazards may be impaired.

WARNINGS:

• Installation of cable connections and servicing of this product require access to shock hazard
voltage levels.

• Main power and relay contacts wired to separate power source must be disconnected before
servicing.

• Main power must employ a switch or circuit breaker as the disconnecting device for the equipment.

• Electrical installation must be in accordance with the National Electrical Code and/or any other

applicable national or local codes.

• Safety and performance require that this instrument be connected and properly grounded through
a three-wire power source.

• RELAY CONTROL ACTION: the 2000 instrument relays will always de-energize on loss of power,
equivalent to normal state, regardless of relay state setting for powered operation. Configure any
control system using these relays with fail-safe logic accordingly.

• PROCESS UPSETS: Because process and safety conditions may depend on consistent operation
of this instrument, provide appropriate means to maintain operation during sensor cleaning,
replacement or sensor or instrument calibration.

This manual includes specific safety information with the following designations and formats:

WARNING: OF POTENTIAL FOR PERSONAL INJURY.
CAUTION: of possible instrument damage or malfunction.
NOTE: important operating information.

On the instrument indicates: Caution, risk of electric shock

On the instrument indicates: Caution (refer to accompanying documents)

TABLE OF CONTENTS

Chapter 1: Getting Started............................................................................................ 1

Introduction..................................................................................................................1

Features ...................................................................................................................... 1

Overview of Operation................................................................................................. 1

Installation & Setup Procedure....................................................................................2

Chapter 2: Installing the 2000 ...................................................................................... 3

Unpacking.................................................................................................................... 3

Installation ...................................................................................................................3

Electrical Connections.................................................................................................3

Chapter 3: Using the 2000............................................................................................ 7

Applying Power to the 2000......................................................................................... 7

The Display.................................................................................................................. 7

The Keypad................................................................................................................. 8

Using the Menus.......................................................................................................... 9

Installing a Sensor..................................................................................................... 10

Measurement Designations.......................................................................................10

Displaying Measurements ......................................................................................... 10

Alarm Indications.......................................................................................................12

Chapter 4: Making Measurements............................................................................. 13

Measurement Process ............................................................................................... 13

Measurement Types.................................................................................................. 13

Selecting a Measurement Type.................................................................................17

Cell Constants........................................................................................................... 17

Conductivity Temperature Compensation.................................................................. 18

pH/ORP Temperature Compensation ........................................................................ 19

Dissolved Oxygen Temp and Pressure Compensation. ............................................ 20

AC Power Frequency.................................................................................................20

Chapter 5: Using Setpoints ........................................................................................ 21

Overview.................................................................................................................... 21

Setpoint Signal .......................................................................................................... 21

Setpoint Value........................................................................................................... 21

Setpoint State............................................................................................................21

Assigned Relay.......................................................................................................... 22

Programming a Setpoint............................................................................................ 22

USP & EP Setpoints.................................................................................................. 23

Chapter 6: Using Relays.............................................................................................24

Description................................................................................................................. 24

Electrical Connections............................................................................................... 24

Delay Time ................................................................................................................ 24

Hysteresis.................................................................................................................. 24

Relay State................................................................................................................24

Programming a Relay................................................................................................ 24

Chapter 7: Using Analog Outputs .............................................................................. 27

Description................................................................................................................. 27

Programming the Analog Outputs ............................................................................. 27

Analog Output Calibration.......................................................................................... 29

Chapter 8: Meter Calibration...................................................................................... 30

Overview.................................................................................................................... 30

Calibration Verification...............................................................................................30

Calibration Procedure................................................................................................ 31

Chapter 9: Sensor Calibration.................................................................................... 34

Conductivity/Resistivity Cell Constants......................................................................34

Conductivity/Resistivity Sensor Calibration................................................................ 34

pH/ORP Sensor Calibration....................................................................................... 36

pH Sensor Diagnostics.............................................................................................. 38

Dissolved Oxygen Sensor Calibration ....................................................................... 38

Dissolved Ozone Sensor Calibration......................................................................... 42

Chapter 10: Security/Lockout.....................................................................................44

Security Features ...................................................................................................... 44

Changing the Password............................................................................................. 44

Enabling the Lockout................................................................................................. 44

Accessing a Locked Menu......................................................................................... 44

Chapter 11: Other Functions...................................................................................... 46

Averaging .................................................................................................................. 46

System Reset............................................................................................................ 46

Setting the Temperature Source................................................................................ 47

Sending Data to a Printer or Computer ..................................................................... 47

Chapter 12: Troubleshooting ..................................................................................... 49

Off-Line Self-Diagnostics...........................................................................................49

On-Line Diagnostics ................................................................................................. 49

Troubleshooting......................................................................................................... 50

Recovery Procedure ................................................................................................. 50

Chapter 13: Service..................................................................................................... 51

Fuse Replacement .................................................................................................... 51

Reducing 2000 Patch Cord Length............................................................................ 51

Recommended Spare Parts List................................................................................ 52

Accessories............................................................................................................... 52

Chapter 14: Technical Illustrations............................................................................ 53

Menu Trees ............................................................................................................... 54

Overall Dimensions.................................................................................................... 57

Panel Cutout.............................................................................................................. 58

Exploded Assembly................................................................................................... 58

Pipe Mounting............................................................................................................ 59

Sealed Back Cover Assembly ................................................................................... 59

Printed Circuit Board Layout...................................................................................... 60

Rear Panel Wiring and Patch Cords.......................................................................... 61

Conductivity Calibrators.............................................................................................62

Meter Calibration Connections .................................................................................. 62

SPECIFICATIONS........................................................................................................ 63

RATINGS......................................................................................................................65

WARRANTY ................................................................................................................. 66

CHAPTER 1: GETTING STARTED

Setpoints (alarms): 4 independent alarms

INTRODUCTION

The 2000 is an analytical and process control
instrument for measuring solution properties. It
can process two sensor inputs for pH, ORP
(redox potential), conductivity or resistivity, or one
sensor input for dissolved oxygen or dissolved
ozone, in all combinations except for ozone and
four-electrode conductivity. A liquid crystal display
conveys measuring data and setup information.
The display is backlit for viewing in all lighting
conditions. The menu structure allows the
operator to modify all operational parameters by
using keys on the front panel. A menu-lockout
feature, with password protection, is available to
prevent the unauthorized use of the meter. The
2000 can have up to four relays for process
control.

The 2000 instrument is equipped with a
communication interface that can be configured
as either an RS422 or an RS232. This interface
provides real-time data output and complete
instrument configuration capabilities for central
monitoring via personal computer or
Programmable Logic Controller (PLC). An
external isolator for the digital communications
signal is required if measurements other than
conductivity with 0.1/cm cell constants are being
made. For coverage of communications, see
Manual 84423.

FEATURES

Display: 16 character backlit LCD.
Measurements: pH, ORP (redox potential),

resistivity, conductivity, dissolved oxygen,
dissolved ozone, °C, °F, total dissolved solids,
%rejection, difference, ratio, %HCl, %NaOH,
%H2SO4.

Measurement Channels: 2.
Signal Inputs per channel: 2 (total of 4 signals

for measurement).
Measurement Cycle Time: 1 second (4

measurements processed per second).
Programmable: all setup information is stored in

non-volatile memory.

programmable as high, low, USP, or EP limits.
Relays: up to 4 with programmable delay time

and hysteresis.

Outputs: 2 analog outputs (0/4-20mA).
Communications: RS232/RS422 interface, bi-

directional; external isolator recommended with
measurements other than conductivity with

0.1/cm cell constants.

Security: keypad lockout with password.
Calibration: complete instrument, output, and

sensor calibration; can be NIST traceable.
Built-In Diagnostics: several self tests can be

initiated at any time.

OVERVIEW OF OPERATION

When power is applied to the 2000, the
initialization process begins. The instrument will
perform a number of self tests. Any problems
detected during these tests will be reported by a
displayed message.

Next, all setup parameters (setpoints, states,
relay conditions, etc.) are restored from a non­volatile memory.

The meter will then begin the measurement
process. A complete measurement cycle is
performed once per second and consists of the
following:

1. Measure four signals and compute four
measurements.

2. Check setpoints against the measurements.

3. Control the relays.

4. Update analog output signals.

5. Transmit measurement data over the
communication port.

6. Display data (if not displaying a menu).

At any time during this process the menus can be
accessed by pressing one of the menu keys. The
display of a menu will not affect the measurement
process.

Chapter 1 Getting Started 1

INSTALLATION & SET UP
PROCEDURE

The following guideline shows the steps
necessary to install a 2000 meter and begin
operation.

1. Follow the meter installation procedure for
physically mounting the meter, as outlined in
Chapter 2. The meter may be mounted in a
panel, on a pipe, or on a wall.

Optional: the rear cover is required for wall
and pipe mounting. Drill holes as needed for
conduit or cable grips, install the cover and
wire the meter before wall or pipe mounting.

2. Make all necessary electrical connections to
the meter after panel mounting. The wiring
procedure is outlined in Chapter 2.

3. Required wiring: input power and sensor

cables.

CAUTION: Be certain that patch cord is wired
specifically for the type of sensor to be
connected or damage could result.

12. Optional: program the relays as shown in
Chapter 6.

13. Optional: program other features such as
averaging method, special temperature
compensation, security/password, etc, as
needed.

4. Optional wiring: relays, analog outputs, and
serial port.

5. Set appropriate input line frequency to
reduce measurement noise. See AC
POWER FREQUENCY in Chapter 4.

6. Instrument calibration is performed at the
factory to specifications. Re-calibration is not
necessary. If QA/QC practice requires it,
meter calibration may be verified as outlined
in Chapter 8.

7. Connect sensors to the patch cords.

8. Select the desired measurements for each
sensor as shown in SELECTING A
MEASUREMENT TYPE in Chapter 4.

9. Enter sensor constants from the label of
each cell as outlined in ENTERING/EDITING
CELL CONSTANTS in Chapter 9. DO NOT
PERFORM A SENSOR CALIBRATION
except for pH, dissolved oxygen or ozone.

10. Optional: program the analog outputs as
shown in Chapter 7. DO NOT
AN OUTPUT CALIBRATION.

PERFORM

11. Optional: program the setpoints as shown in
Chapter 5.

2 Getting Started Chapter 1

CHAPTER 2: INSTALLING THE 2000

UNPACKING

Each 2000 is packed in an individual
biodegradable carton. Retain the packaging in the
event that the instrument must be returned to
Thornton for service or calibration.

This carton should contain:
1 - 2000 Instrument
1 - Set of panel mounting hardware with

gasket
1 - 02192 kit of 2 ferrite bead noise

suppression modules
1 - 84401 Instruction Manual
1 - 84402 Startup Instruction Sheet
1 - Certificate of Calibration

INSTALLATION

The 2000 can be mounted in a panel, on a pipe
or attached to a wall.

Panel Mounting Cutout
and Installation

The panel cutout should measure 7.56 inches
wide by 3.780 inches high (192 mm X 96 mm).
Drill four holes for the #10 mounting screws. See
Figure 14.3 for panel cutout size and mounting
screw hole spacing. When mounting multiple
instruments on the same panel, note the front
flange dimensions in Figure 14.2 in order to allow
enough space between instruments.

Panel cutouts should be clean and free of burrs
and sharp edges. The proper dimensions allow
an instrument to slide freely into the cutout.

Install the panel gasket (supplied with instrument)
on the instrument mounting flange. Slide the
instrument into the cutout and secure it with the
mounting screws.

CAUTION: Do not over tighten the screws as
this may crack the case.

If the rear cover is used in a panel mounted
installation, the 2000 unit must be installed in the
panel opening before the rear cover is installed.

Wall Mounting

The 2000 can be easily mounted to a wall when
the rear cover is installed. The flanges on the
ends of the cover contain holes for screws to
fasten the assembly to the wall. A layout for
drilling mounting holes is included in the wall
mount kit.

Pipe Mounting

The 2000 can be mounted to a pipe with the pipe
mounting accessory kit. The assembly is shown
in Figure 14.5.

ELECTRICAL
CONNECTIONS

All electrical connections are made at plug-in
terminal blocks at the rear of the 2000 case.

WARNING: MAKE SURE POWER TO ALL
WIRES IS TURNED OFF BEFORE PRO­CEEDING WITH THE INSTALLATION. HIGH
VOLTAGE MAY BE PRESENT ON THE INPUT
POWER WIRES AND RELAY WIRES.

CAUTION: A good power earth ground
connection is required for safety and for
proper operation of the instrument. To prevent
electrostatic discharge (ESD) from damaging
the instrument during installation, the installer
must also be electrically grounded i.e., wear a
conductive wrist strap connected to earth
ground.

Do not run power and relay wiring in the same
conduit or parallel with sensor and output
signal wiring to prevent interference.

Input Power and Relay Connections

Terminal block TB1 contains connections for the
input line power and relay contacts. Depending
upon the model number, the 2000 will have either
2 or 4 relays. Table 2.1 shows the wiring
sequence.

All relays have “dry contacts”; they are potential­free and require external power to be wired in
series with the load and instrument terminals.
Relays 3 and 4, if specified, are solid state AC-

Chapter 2 Installation 3

only relays (triacs) and require a minimum current
of 10 mA to switch reliably. With very small loads
such as a neon bulb, test meter or PLC, a load
resistor is required in parallel with the load, e.g. a
10K ohm, 2 watt resistor, for operation with 115
VAC.

WARNING: IF THE INPUT VOLTAGE
JUMPERS ARE CHANGED YOU MUST LABEL
THE UNIT WITH THE NEW VOLTAGE
REQUIREMENT. ALSO, THE FUSE MUST BE
CHANGED TO THE PROPER RATING TO
AVOID RISK OF FIRE HAZARD

TB1
Label

Input Power & Relay
Function

L 115V/230 VAC Line
N 115V/230 VAC Neutral

Earth Ground

NC1 Relay1: Normally Closed
C1 Relay1: Common
NO1 Relay1: Normally Open

NC2 Relay 2: Normally Closed
C2 Relay 2: Common
NO2 Relay 2: Normally Open

C3 Relay 3: Common
NO3 Relay 3: Normally Open

C4 Relay 4: Common
NO4 Relay 4: Normally Open

Table 2.1: Input Power & Relay Connections

WARNING: MISWIRING THE AC POWER MAY
DAMAGE THE INSTRUMENT AND WILL VOID
ALL WARRANTIES.

Setting Input Voltage
for 115 VAC or 230 VAC

The input voltage for a 2000 can be set for either
90-130 VAC or 180-250 VAC operation. The input
voltage is preset at the factory and is indicated on
the serial number label on the side of the unit.
Jumpers on the printed circuit board can be
changed to change the input voltage. See Figure

14.7. W4 jumper pins are located between the

power transformer and the fuse. For 90-130 VAC
operation jumper pins 1-2 and 3-4 must be used.
For 180-250 VAC operation only a jumper on pins
2-3 must be installed. The jumpers can be
accessed by removing two screws from the back
panel and carefully lifting the panel off.

Fuse requirements:
For 90-130 VAC: 1/8 Amp, SB, 250 VAC
For 180-250 VAC: 1/16 Amp, SB, 250 VAC
NOTE: If the line power frequency is changed,

select the correct setting (see AC POWER
FREQUENCY in Chapter 4).

Setting Input Voltage for 24 VDC

The 2000 can be operated from a +24 VDC
power supply instead of the typical 90-130 VAC
or 180-250 VAC source.

NOTE: 24 VDC power supply must be isolated
from earth ground and between instruments. Use
a DC/DC power isolator if necessary.

Remove any AC power connections from terminal
block TB1.

1. Move circuit board jumper W6 to the 24V
position (left two pins) as shown in Figure

14.7.

2. Connect + 24V DC power to the connection
labeled PS+ on terminal block TB3. Connect
the power supply ground to the connection
labeled PS- on TB3.

WARNING: AC POWER CONNECTIONS MUST
BE REMOVED WHEN USING THE +24V
POWER INPUT.

NOTE: The +24 VDC input is not fused within the

meter. Use an external fuse.

AC Power Wiring

In order to maintain safety for the electrical
installation, no more than 6 mm of insulation is to
be removed from each conductor before fully
inserting into the electrical terminal.

The plug-in terminal blocks for all connections
will accept wire sizes from 26 AWG (0.126 mm
to 14 AWG (2.08 mm
to 12 AWG (3.31 mm

2

), solid or stranded and up

2

) stranded only.

2

)

4 Installation Chapter 2

Output Connections

Connections for all outputs are made to terminal
block TB4. The serial port can be configured as
an RS232 port (shown in Table 2.2.) or an RS422
port (shown in Table 2.3). An external isolator for
digital communications is strongly recommended
to prevent ground loop problems.

TB2
Label

AO2- Output 2 (-)
AO2+ Output 2 (+)
AO1- Output 1 (-)
AO1+ Output 1 (+)

Analog Output
Function

TB2 Label RS232 Function

DGND Ground
TXD+ Not Used
TXD- Transmit Data
RXD+ Not Used
RXD- Receive Data

Table 2.2: RS232 Connections

TB2 Label RS422 Function

DGND Ground
TXD+ Transmit Data Positive
TXD- Transmit Data Negative
RXD+ Receive Data Positive
RXD- Receive Data Negative

Table 2.3: RS422 Connections

Each analog output has + and – connections.
Analog outputs are self-powered with a maximum
load resistance of 500 ohms.

CAUTION: Do not connect analog outputs to
circuits supplying power.

CAUTION: Do not connect analog output
cable shield(s) to the adjacent DGND
terminals. Connect shield(s) only to one of the
earth ground terminals next to AC line power.

Table 2.4: Analog Output Connections

Sensor Patch Cord Connections

The sensors are connected to plug-in terminal
blocks TB2 and TB3. Each channel has nine
terminals for the sensors plus earth ground.
Patch cords, 1XXX-67 or 58 080 20X series, for
the 2000 have a connector on one end and tinned
leads on the other end. Table 2.5. shows the
wiring pattern for each type of sensor.

CAUTION: Wiring for each type of sensor is
different. Miswiring patch cords may damage
sensors and will void all warranties. Verify
wire colors in table 2.5. Disconnect power
before wiring sensors to prevent damage to
the input circuit.

If sensors other than conductivity must be
wired with the instrument powered, make the
PS- connection first to prevent damage to the
input circuit.

To meet CE electromagnetic compatibility
requirements for emissions Class B, install a

ferrite suppression module from kit 02192 on
each sensor patch cord as close to the instrument
as possible.

NOTE: For ultrapure water conductivity
measurements with all-plastic piping, especially
semiconductor wet benches, it is recommended
to connect a jumper from one of the three earth
ground terminals to sensor ground terminal
SIG6(6) on TB3 for Channel A. This will prevent
possible instrument damage due to electrostatic
charges that build up in plastic piping systems.
Do not use a ground jumper with higher
conductivity water, with metal piping or with pH or
ORP measurements.

Chapter 2 Installation 5

Terminal Cond/

Resistivity

EARTH GND*

PS-

+5V (9)
I/O (8) Ch A**
I/O (8) Ch B**

SIG7(7)
SIG6(6)
SIG5(5)

SHIELD

BLACK

-

-

-

-

BLUE

RED

pH/ORP Dissolved

Oxygen

SHIELD

BLACK

BLUE

-

-

WHT/BLU

-

RED

-

BLACK

BLUE

WHT/BLU

RED

SHIELD

-

CLEAR

Ozone

SHIELD

BLACK

BLUE

WHT/BLU

RED

JUMP-5***

-

CLEAR

Alternative 3-Lead Conductivity
Sensor Connections

Tinned-lead cells with 1000 Pt or 500 Ni-Fe RTDs
may be used with the 2000. These sensors, with
integral leadwire and no connector, enable the
lead to pass through small openings. The
sensor/instrument separation is limited to less
than 50 feet (20 feet recommended).

Somewhat lower accuracy may result.
Connections are given in Table 2.6. Jumpers
should be 22 gauge to match the conductor size
in the cable, for secure terminal connections.

SIG4(4)
SIG3(3)
SIG2(2)
SIG1(1)

* Connect to any of three earth ground terminals.
** Connections for dissolved oxygen and ozone use

both channel A and B I/O terminals regardless of

which channel is assigned for that measurement.
*** Install a wire jumper between terminals 5 and 7.
For instruments with firmware version 2.0 and earlier

(before April 2004), pH, ORP and dissolved oxygen
connections must connect the black wire to SIG6(6)
instead of PS-. Ozone measurement requires firmware
version 4.0 or higher.

GREEN

WHITE
CLEAR

WHT/BLUE

GREEN

WHITE
CLEAR

GREEN

WHITE

-

GREEN

WHITE

-

-

-

-

Table 2.5: Sensor Patch Cord Connections

Voltage and current measuring terminals are
rated for overvoltage category II.

Sensor Models/Types

240-, 243- 2-Electrode Conductivity
244- 4-Electrode Conductivity
363- & 1200- pH or ORP
367- dissolved oxygen

Terminals Three-lead Conductivity

Sensor Wiring

+5V (9)
I/O (8)
SIG7(7)
SIG6(6)
SIG5(5)
SIG4(4)
SIG3(3)
SIG2(2)
SIG1(1)

-

­Jumper to SIG(6)
Jumper to SIG(5)
CLEAR (shield)
WHITE
Jumper to SIG(1)

­RED

Table 2.6: Alternative Sensor Connections

With these 2_8 Series Dot Two sensors there is
no label with factory-supplied precision calibration
constants. Only the nominal value 0.1/cm for cell
constant and 1.0 for temperature constant are
entered into the 2000.

With all tinned-lead sensors, when meter
calibration is desired, the cell must be
disconnected and a patch cord installed in its
place to accept a calibrator.

368- dissolved ozone

6 Installation Chapter 2

CHAPTER 3: USING THE 2000

APPLYING POWER TO THE 2000

After applying power to the meter, the display will
show an introduction message for three seconds
and then begin making measurements. This
message shows the model number and the
software version number as follows:

In the menus, an underline cursor and flashing
(bold) characters will indicate a field that can be
changed. A typical menu appears as follows:

SP1=17.00 M High

68XX Ver X.X

While the message is being displayed the
instrument is performing self diagnostics. Various
circuits are tested during this process and any
failure will be noted with a message. The
diagnostics can be repeated at any time via the
menus.

The default measurement display is the primary
readings from the sensors on channel A and B as
shown below:

A1.76µS B2.11µS

All 2000 meters are calibrated from the factory
and normally require no further calibration. If
QA/QC practice requires it, the instrument be
calibrated after installation. See Chapter 8 for
more information on meter calibration.

THE DISPLAY

The 2000 uses a 1 line by 16 character
alphanumeric display to convey all measurement
and setup information. This instrument will display
one or two measurements, each with channel
indication and unit of measure. A typical display
of measurement data is:

This menu indicates that setpoint #1 is
programmed at a value of 17.00 M (million) and is
set as a high limit. The cursor is under the digit
“7” indicating that the UP and DOWN keys can be
used to change it. The RIGHT and LEFT keys will
move the cursor to the next or previous field.

Display Contrast Adjustment

The contrast quality of the display can change
with ambient temperature. The display contrast is
adjusted from the factory for operation at
standard room temperature (25°C). If the meter is
operated at an ambient temperature that is much
different then it may be necessary to make an
adjustment. A potentiometer is accessible from
the back side of the instrument to change the
contrast. Use a small slotted screwdriver to gently
turn the potentiometer. A counter-clockwise turn
will increase the contrast and a clock-wise turn
will decrease the contrast. The rear panel is
shown in Figure 3.1.

A7.76pH B2.10µS

This display indicates that channel A is
measuring 7.76pH and channel B is measuring

2.10µS/cm. The display of the other
measurements can be achieved by pressing the
UP or DOWN keys.

Chapter 3 Using the 2000 7

Figure 3.1: 2000 Rear Panel

THE KEYPAD

The 2000 is equipped with an 11-key keypad as shown in Figure 3.2.

THORNTON

A1.076µS

Figure 3.2: 2000 Front Panel

8 Using the 2000 Chapter 3

B1.055µS

2000

The keypad has 6 keys that provide direct access
to specific menus as follows:

instrument to accept the options that are
displayed and move to the next menu.

1. MEASURE MODE - menus to change

measurement modes.

2. SETPOINTS - menus for programming

setpoints.

3. RELAYS - menus for programming relays.

4. OUTPUTS - menus for programming

outputs.

5. CALIBRATE - menus to perform calibration.

6. MENUS - all other menus (cell constants,

security, compensation, averaging, etc.).

The other keys are referred to as control keys
and are used to make changes within a menu.

1. OK/NEXT Key - used to accept a selection

and proceed to the next menu level.

2. UP Key - up arrow is used to scroll up

through a list of options.

3. DOWN Key - down arrow is used to scroll

down through a list of options.

4. LEFT Key - left arrow is used to move the

cursor to the left within a menu.

5. RIGHT Key - right arrow is used to move the

cursor to the right within a menu.

USING THE MENUS

There are six menu keys across the bottom of the
2000 front panel. The first five of these keys
(MEASURE MODE, SETPOINTS, RELAYS,
OUTPUTS, AND CALIBRATION) are used to
enter specific menus. These menus allow the
modification of parameters most frequently used
by the operator. The sixth key labeled MENUS
allows access to all other menus for various
functions such as setting compensation methods,
security levels, etc.

The UP and DOWN arrow keys scroll vertically
through the menus. Part or all of the display
changes to the next option whenever an UP or
DOWN arrow key is pressed. A field is defined as
a section of the display that can be changed. The
characters of the field will also blink. The LEFT
and RIGHT arrow keys move the underline cursor
across the display from one field to the next.
Pressing the OK/NEXT arrow key causes the

Numbers are set one digit at a time using the
arrow keys. The LEFT and RIGHT arrow keys are
used to position the underline cursor below the
digit to be changed. The UP and DOWN arrow
keys are then used to change the value of the
digit. Each digit can be scrolled through the
values: .(decimal point), 0, 1, 2, 3, 4, 5, 6, 7, 8,
and 9 The first digit of any number can also be
set to a negative sign (-).

To exit the menus either scroll completely through
a set of menus with the OK/NEXT key or press
any of the six menu keys at any time. The meter
will display a prompt asking if the recent changes
should be saved.

Save Changes Yes

To save the changes press the OK/NEXT key
with “Yes” on the display. To discard the changes
use the UP or DOWN arrow keys to change “Yes”
to “No”, then press the OK/NEXT arrow key.

If the instrument is displaying a menu and a key
is not pressed for two minutes, the instrument will

automatically exit the menus without saving any
changes. When performing a calibration the

operator may need to wait for a measurement to
stabilize so the menu time-out feature is
automatically disabled.

Menu Example

Press the MEASURE MODE key and the display
will show:

A=S/cm (AUTO)

This menu indicates that the Channel A primary
measurement is set for conductivity (S/cm) with
auto ranging. The section “S/cm” is the field to
be changed and will be flashed as long as the
cursor is under it. Pressing the UP arrow key will
change the “S/cm” to “Ω-cm”. The RIGHT arrow
key will move the cursor to the “(AUTO)” field.

A=Ω/cm (AUTO)

Chapter 3 Using the 2000 9

The OK/NEXT key is used to accept the entry
and move to the next menu. When the last menu
level is reached the following message is
displayed:

b = channel B secondary measurement
Upper case letters are used to indicate the

primary measurements and lower case letters are
used to indicate the secondary measurements.

Save Changes Yes

Pressing the OK/NEXT key will save the changes
and exit the menus. The UP and DOWN arrow
keys can be used to change the “Yes” to “No”.
Pressing the OK/NEXT key with “No” will discard
the changes and exit the menus.

INSTALLING A SENSOR

Each sensor is equipped with a cell and
temperature sensor (except ORP). Conductivity
sensors have calibration constants for these
elements that must be programmed into the
meter for proper operation. These factors are
printed on the sensor (as well as a Certificate of
Calibration supplied with each conductivity
sensor). The label may look like this:

RES M=1.0034 TEMP M=1.0015

RES M is the conductivity cell constant, and
TEMP M is the temperature sensor constant. pH
preamps will have a pH A (adder) constant. Long
life 367-110 dissolved oxygen sensors have Cell
M (multiplier), Cell A (adder) and TEMP M
(multiplier) constants. See ENTERING/ EDITING
CELL CONSTANTS in Chapter 9 for information
on entering cell constants.

Each of the four calculated measurements can be
one of the following:

1. pH

2. ORP (redox potential)

3. Resistivity

4. Conductivity

5. Total Dissolved Solids (TDS)

6. Degrees C

7. Degrees F

8. % Rejection

9. Difference (A-B or B-A)

10. Ratio (A/B or B/A)

11. %HCl

12. %NaOH

13. %H2S0

14. Dissolved Oxygen

15. Dissolved Ozone

16. Power plant calculations of pH, CO
chlorides or sulfates from conductivity

4

2

DISPLAYING MEASUREMENTS

,

MEASUREMENT DESIGNATIONS

The 2000 instrument will measure four
fundamental signals during each measurement
cycle. These measurements are the conductivity,
pH or dissolved oxygen and temperature of the
probe on channel A and the conductivity or pH
and temperature of the probe on channel B.

The 2000 can process and display four calculated
measurements. They are referred to as A
primary, A secondary, B primary and B
secondary. These measurements are designated
by a single letter as follows:

A = channel A primary measurement
a = channel A secondary measurement
B = channel B primary measurement

10 Using the 2000 Chapter 3

Changing the Display
of Measurements

The 2000 display can show either one or two
measurements at a time. The display of
measurements can be changed by using the UP
or DOWN arrow keys. Pressing one of these keys
will cause the meter to change the display mode
(show an alternative set of data).

The display modes for two measurements per
line are:

Mode #1: A primary and B primary (three
significant digits displayed for each parameter):

A1.76µS B2.11µS

Mode #2: A secondary and B secondary (three
significant digits displayed for each parameter).

Press the MENUS key and the following menu
will appear:

a25.2°C b25.1°C

Mode # 3: A Primary and A Secondary (four
significant digits displayed for each parameter):

A1.764µS 25.10°C

Mode #4: B primary and B Secondary (four
significant digits displayed for each parameter):

B2.109µS 25.12°C

Note that when two measurements from the
same channel are displayed, the secondary
measurement indicator ( a or b) is not displayed.
This allows for greater precision in the display of
the primary measurement.

The default display setting (after a system reset)
is mode #1 (A Primary & B Primary).

The display modes for one measurement per line
are:

Mode #1: A Primary:

Menus use arrows

Press the UP arrow key until “Display Menus” is
displayed.

Display Menus

Press the OK/NEXT key to access this menu.
Use the Up or DOWN keys to toggle the field until
“Disp Format” appears. Press OK/NEXT to
access this menu.

Set: Disp Format

Use the UP and DOWN keys to toggle the field
between “1” and “2”.

Measure per Line: 1

Press OK/NEXT when done. The meter will ask if
changes should be saved.

Save Changes Yes

A 1.765µS/cm

Mode #2: A Secondary:

a 25.25 deg C

Mode #3: B Primary:

B 2.109µS/cm

Mode # 4: B Secondary:

b 25.12 deg C

Setting the Number of Measurements
per Display Line

The 2000 can be set to display either one or two
measurements per line.

To change this feature:

Press OK/NEXT key to save the changes and
return to the display of measurement data.

Measurement Display Scrolling

The 2000 has an automatic display scrolling
feature for measurement data. With this feature
enabled, the display will show channel A data for
5 seconds and then show channel B data for 5
seconds. Secondary measurements are not
shown if a single measurement is selected per
display line. The process is repeated indefinitely.

To enable or disable this feature:
Press the MENUS key and the following menu

will appear:

Menus use arrows

Press the UP arrow key until “Display Menus” is
displayed.

Display Menus

Chapter 3 Using the 2000 11

Press the OK/NEXT key to access this menu

Set: Auto Scroll

Use the Up or Down arrow keys to toggle the field
until “Auto Scroll” appears. Press OK/NEXT to
access this menu.

Auto Scroll=off

Use the UP or DOWN arrow keys to toggle the
field from “Off” to “On”. Press the OK/NEXT key
when done. The meter will ask if changes should
be saved.

Save Changes Yes

Press the OK/NEXT key to save the changes and
return to the display of measurement data.

ALARM INDICATIONS

A setpoint can be programmed as a high limit, a
low limit, USP or EP (temperature-dependent
pharmaceutical water conductivity) limits. When a
measurement is higher than a high, USP or EP
point or lower than a low point then the setpoint is
in alarm state. This condition is indicated by
flashing the corresponding measurement value in
the normal operating display. See Chapter 5:
Using Setpoints.

12 Using the 2000 Chapter 3

CHAPTER 4: MAKING MEASUREMENTS

MEASUREMENT PROCESS

The 2000 will process two measurements from
each of the two channels. The measurements of
each channel are referred to as the primary and
the secondary measurement. The instrument will
process a total of four different measurements
per cycle.

Measurements are designated as follows:
A = channel A primary measurement
a = channel A secondary measurement
B = channel B primary measurement
b = channel B secondary measurement

Upper case letters indicate primary
measurements and lower case letters indicate
secondary measurements.

MEASUREMENT TYPES

Each of the four measurements (channel A
primary, etc.) is programmed as one of the
following with corresponding 1 or 2-character
display:

Measurement

pH
ORP (redox potential)
Resistivity

Conductivity – siemens/cm,
siemens/m
Total Dissolved Solids (TDS), ppm,
ppb

Dissolved Oxygen – g/L, ppm, ppb,
% saturation

Dissolved Ozone – ppm (mg/L),
ppb (µg/L)

Temperature – Deg C, Deg F
% Rejection
Difference (A-B or B-A)
Ratio (A/B or B/A)
%HCl - Hydrochloric Acid
%NaOH - Sodium Hydroxide
%H2S04 - Sulfuric Acid

Display

pH

V
Ω

S, Σ

PM, PB

g, pm,

pb, %

Z,

z

°C, °F

%R

d

r
%H
%N
%S

Power cycle chemistry calculations
of pH, CO

, Chloride, Sulfate

2

PH, CD,

Cl, Sf

pH and ORP (Redox potential)

pH is displayed with fixed range. ORP is
displayed in fixed range millivolts (mV).

Resistivity

Resistivity is expressed in ohms-centimeter (Ω-
cm). This measurement can be displayed with a
prefix in front of the units. The prefixes are k (kilo
or 1,000) and M (Mega or 1,000,000).

The display can be set for a fixed range such as
Ω-cm, KΩ-cm (1,000Ω-cm), or MΩ-cm (Mega or
1,000,000Ω-cm). The 2000 can also be set for
auto ranging where the range will be
automatically adjusted for the most appropriate
display. The range is set via the measure mode
menus.

1,000,000 Ω-cm = 1,000 KΩ-cm = 1 MΩ-cm

Conductivity

Conductivity is expressed in siemens per
centimeter (S/cm) and is the reciprocal of
resistivity. This measurement can be displayed
with a prefix in front of the units. The prefixes are
m (milli or 1/1,000) and µ (micro or 1/1,000,000).
The 2000 can also be set for auto ranging where
the range will be automatically adjusted for the
most appropriate display. The range is set via the
measure mode menus.

1 S/cm = 1,000 mS/cm = 1,000,000 µS/cm
Conductivity may also be expressed in siemens

per meter
units as described above. To clearly distinguish
these units in the 2000 display, the symbol “Σ” is
used in place of “S”. In operation, microsiemens
per meter is displayed as µΣ.

(S/m) with a multiplier in front of the

Total Dissolved Solids

Total Dissolved Solids (TDS) is another way to
measure and display conductivity/resistivity data.
TDS is the equivalent of Sodium Chloride (NaCl)
required to produce the measured conductivity-­approximately 0.46 ppm TDS per µS/cm. If some

Chapter 4 Making Measurements 13

other conversion is desired, it is necessary to
adjust the cell constant to give direct readout. For
example, if a conversion of 0.6 ppm TDS per
µS/cm is desired, the cell multiplier to be entered
into the 2000 is 0.6/0.46 x Multiplier on sensor
label. See Chapter 9, Entering/Editing Sensor
Constants.

TDS is measured in parts per billion (ppb), parts
per million (ppm), or parts per thousand (ppk). A
TDS reading of 10 ppm is equivalent to 10
milligrams per liter. Because of space limitations,
the following abbreviations are used to display
TDS units:

PB = parts per billion

Temperature

Temperature can be measured in degrees
Celsius (°C) or degrees Fahrenheit (°F). The
2000 normally works with a 1000 ohm DIN
platinum RTD sensor which is built into Thornton
most conductivity, dissolved oxygen, dissolved
ozone and most pH sensors. Alternatively, the
2000 can automatically recognize and measure
with a 500 ohm Ni-Fe RTD temperature sensor.
When configured for a 50/cm constant cell only,
the 2000 automatically changes its characteristic
to measure from the 262 ohm @ 25°C thermistor
supplied in those sensors.

PM = parts per million
PK = parts per thousand

Dissolved Oxygen

Dissolved oxygen can be measured in units of
parts per billion (ppb), parts per million (ppm),
and grams per liter (g/L), with or without auto­ranging between micro and milli (grams per liter).
Abbreviations used in the display mode are pb,
pm, µg and mg, respectively. Note that dissolved
oxygen uses lower case pb and pm to distinguish
it from TDS which uses upper case PB and PM.

NOTE: Select dissolved oxygen as a
measurement after connecting the probe. This
initiates an automatic internal preamp calibration
for highest accuracy at startup and will display
“Saving Changes” for an extended period.
Otherwise, the system will initiate calibration by
itself 1 hour later.

Dissolved Ozone

Dissolved ozone can be measured in units of
parts per billion (ppb) with resolution of 1 ppb or
in units of parts per million (ppm) with resolution
of 0.01 ppm. Abbreviations for units in the normal
display mode are z and Z respectively.

NOTE: Select dissolved ozone as a
measurement after connecting the preamp. This
initiates an automatic internal preamp calibration
for highest accuracy at startup and will display
“Saving Changes” for an extended period.
Otherwise, the system will initiate calibration by
itself 1 hour later.

% Rejection

For reverse osmosis (RO) applications, percent
rejection is measured in conductivity to determine
the ratio of impurities removed from product water
to the total impurities in the incoming feed water.
The formula for obtaining Percent Rejection is:

[1 - (Product/Feed)] X 100 = % Rejection

Where Product is the conductivity measurement
of the first sensor and Feed is the conductivity of
the second sensor. Figure 4.1 shows a diagram
of an RO installation with sensors installed for
Percent Rejection.

CONDUCTIVIY

SENSOR

REVERSE OSMOSIS MEMBRANE

B

FEED PRODUCT

Figure 4.1: % Rejection

IMPORTANT: When preparing the system to
perform a percent rejection measurement, the
product monitoring sensor must be installed in the
channel that will measure percent rejection. If the
product conductivity sensor is installed in channel
A, then percent rejection must be measured in
channel A. Likewise if the product sensor is
installed in channel B, then the percent rejection

REJECT

CONDUCTIVITY

SENSOR

A

14 Making Measurements Chapter 4

measurement must also be programmed in
channel B.

Difference (A-B or B-A)

The difference measurement is computed as:

Difference on channel A = A-B.

or

Difference on channel B = B-A.

When the difference is assigned to one channel,
the meter will measure the same type of
measurement mode of the other channel as a
basis. For example, if channel A is set to
measure the difference and channel B is
measuring conductivity, then the 2000 will
measure conductivity on both channels before
computing the difference. The displayed unit for
difference is ‘d’.

Ratio (A/B or B/A)

This measurement is similar to the difference
measurement.

Ratio on channel A = A/B.
Ratio on channel B = B/A.
The displayed unit for ratio is ‘r’.

Concentrations
(%HCl, %NaOH, %H2SO4)

All concentrations are displayed as percent by
weight. Setting a measurement for concentration
automatically activates specialized temperature
compensation for that particular material. The
compensation setting is ignored for that channel.

Power Plant Calculated Parameters

The following derived parameters are valid only
for power plant cycle chemistry samples
conditioned by a cation exchanger (and
sometimes a degasifier) as illustrated in Figure

4.2. They are not applicable to other samples and
would give very erroneous results elsewhere.
Because the 2000 can provide two
measurements from a single sensor channel, it
can be configured to display two conductivity
measurements, sample temperature and
calculated pH or CO

measurements.

2

Calculated pH may be obtained very accurately
from specific and cation conductivity values when
the pH is between 7.5 and 10.5 due to ammonia
or amines and when the specific conductivity is
significantly greater than the cation conductivity.
The 2000 uses this algorithm when CALCPH is
selected using the Measure Mode key for the
channel measuring cation conductivity.

For example, set up measurement ‘A’ to be
specific conductivity, measurement ‘a’ to be
temperature, measurement ‘B’ to be cation
conductivity and measurement ‘b’ to be
calculated pH. Set the temperature compensation
mode to “Ammonia” for measurement ‘A’ and to
“Cation” for measurement ‘B.’

Note that if operation goes outside the
recommended conditions, a glass electrode pH
measurement is needed to obtain an accurate
value. On the other hand, the calculated pH
provides an accurate standard for one-point trim
calibration of the electrode pH measurement
when sample conditions are within the ranges
noted above.

Carbon dioxide may be calculated from cation
conductivity and degassed cation conductivity
using tables from ASTM Standard D4519. The
2000 has these tables stored in memory which it
uses when units of CO2ppb are selected under
the Measure Mode key.

For example, set up measurement ‘A’ to be cation
conductivity, measurement ‘a’ to be CO2ppb,
measurement ‘B’ to be degassed cation
conductivity and measurement ‘b’ to be
temperature. Set the temperature compensation
mode to “Cation” for both conductivity
measurements.

Total anions as chlorides or sulfates may be
readout on a degassed cation conductivity
sample using tables from ASTM Standard D4519.
The 2000 has these tables stored in memory
which it uses when selected under the Measure
Mode key by choosing units of “Clppb” or
“SO4ppb” for parts per billion chlorides or
sulfates. Conductivity is non-specific and cannot
determine the actual anions present—it merely
converts the conductivity value as if they were all
chlorides or all sulfates. Set the temperature
compensation mode to “Cation”.

The display units for these derived parameters
are given below.

Chapter 4 Making Measurements 15

Measurements Menu Normal Display

PHCALC ( ) PH
CO2ppb ( ) CD

pH calculated from conductivity is designated by
all upper case ‘PH’. pH measured by electrode is
designated by the conventional lower/upper case

‘pH’.
Clppb ( ) Cl
SO4ppb ( ) Sf

Specific Conductivity

+

NH

, OH-, Na+, H+, Cl-, HCO

4

-

3

CO

2

Degassed Cation Conductivity

+

H

, Cl

+

R–NH

R–Na

4

+

Degas Unit

Cation Exchanger

+

R–H

-

, OH-

3

Cation Conductivity

+

H

, Cl-, CO2, HCO

Fig. 4.2: Sample conditioning for specific, cation and degassed cation conductivity
measurements used to calculate pH, CO

and anion concentration on power plant cycle chemistry

2

samples

-

, OH

-

16 Making Measurements Chapter 4

SELECTING A MEASUREMENT TYPE

To set or change a measurement type for each of
the four measurements:

Press the MEASURE MODE key and the display
will show the measurement type assigned to
channel A primary. The display may appear as:

The field on the right half side of the display is the

range field. Some measurements can be set for a

fixed range, others can be set only for auto

ranging. For example, conductivity can be set for

micro, milli, units, or auto ranging. To change the

field, use the RIGHT arrow key to move the

cursor under “(Auto)”. Use the UP and DOWN

arrow keys to select the desired range.

A = Ω-cm (AUTO)

This menu indicates that channel A primary
measurement is set for resistivity (Ω-cm) with
auto ranging. The section “Ω-cm” is the first field
to be changed and will be flashed as long as the
cursor is under it. Pressing the UP arrow key will
change the “Ω-cm” to “S/cm”.

The OK/NEXT key is used to accept the entry for

channel A primary and move to the next menu for

setting channel “a” secondary. Press the

OK/NEXT key a third and fourth time to set the

measurement types for channel B primary and

channel “b” secondary, respectively.

When the last menu level is reached (after setting

channel “b” secondary), the following message is

displayed:

A = S/cm (AUTO)

Use the UP and DOWN arrow keys to select the
desired measurement type.

For dissolved oxygen, the sensor should be
connected to the 2000 before selecting this
parameter because the 2000 performs a DO
preamplifier calibration when it is saved (and at
hourly intervals thereafter). Also for this reason
there is a long delay in the saving process.

For conductivity, both temperature compensated
and uncompensated measurement are available.
Uncompensated readings are needed to meet
pharmaceutical water requirements. Select units
of “S/cm” for compensated measurement or “s/cm
U” for uncompensated measurement. Using both
primary and secondary parameters, both
compensated and uncompensated
measurements are available simultaneously. In
normal operation, uncompensated measurements
are identified by a flashing cursor under the units,
for example, “µ
are identified by “µS”.

Another option for conductivity is to display in
units of siemens per meter
SI metric system. The Menu setting is

s”. Normal compensated readings

in accordance with the

Pressing the OK/NEXT key will save the changes

and exit the menus. The UP and DOWN arrow

keys can be used to change the “Yes” to “No”.

Pressing the OK/NEXT key with “No” will discard

the changes and exit the menus.

CELL CONSTANTS

The calibration of each measurement is defined

by a set of constants known as cell constants.

There are two cell constants for each

measurement: a Multiplier Factor and an Adder

Factor. They are used to derive an accurate

measurement from the sensor’s output signal. As

an example, the output of a conductivity sensor

can be represented by the following equation:

R = x / M + A

Where:

R = resistivity value

x = output from cell

M = multiplier factor

Save Changes Yes

A = S/m (AUTO)

The measurement mode will display it as “µΣ” or
“mΣ”.

Chapter 4 Making Measurements 17

A = adder factor

Example: for a typical two-electrode conductivity

sensor the multiplier (M) is 0.1 and the adder (A)

is 0. If the sensor output is 120,000 ohms, then

the actual resistivity of the solution measured is

1.2 Mohm-cm and is calculated as follows: