Thermo Fisher Scientific DO 2000 User Manual

Alpha DO 2000 PPG

Processor/Transmitter

Dissolved Oxygen ( ppm / m/L / % )

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Preface

This manual serves to explain the use of the Alpha DO 2000 Series. The manual functions in
two ways, firstly as a step by step guide to help the user operate the instrument, and
secondly as a handy reference guide. This instruction manual is written to cover as many
anticipated applications of the Alpha DO 2000 as possible. If you have any doubts
concerning the use of the instrument, please do not hesitate to contact your nearest Alpha
Authorised Distributor.

The information presented in this manual is subject to change without notice as
improvements are made, and does not represent a commitment on part of Thermo Scientific.

Thermo Scientific cannot accept any responsibility for damage or malfunction of the unit due
to improper use of the instrument.

Copyright ©2008 All rights reserved.

Safety Information

This Controller/ Transmitter shall be installed and operated only in the manner specified in
the Instruction manual. Only skilled, trained or authorised person should carry out
installation, setup and operation of the instrument.

Before powering up the unit, make sure that power source it is connected to, is as specified
in the top label. Failure to do so may result in a permanent damage to the unit.

The unit has live and exposed parts inside. If it has to be opened, make sure that the power
to the unit is off and disconnected.

The unit is Fuse protected. In the event the fuse has to be replaced, use only those as
specified in the manual.

The degree of protection against electric shock will be achieved only by observance of the
corresponding installation rules.

Table of Contents

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

1.1 Before You Begin........................................................................................................................ 1

1.2 Intended Use............................................................................................................................... 1

1.3 Safety Instructions.......................................................................................................................2

1.4 Taking Out of Service / Correct Disposal of the Unit .................................................................. 2

2. Getting Started ......................................................................................................3

2.1 Description of Instrument ............................................................................................................3

2.2 Measurement and Control System.............................................................................................. 4

2.3 Unit Overview.............................................................................................................................. 5

2.3.1 Display Overview...............................................................................................................6

2.3.2 Key functions ..................................................................................................................... 6

2.3.3 LED indicators.................................................................................................................... 7

2.3.4 Security codes ...................................................................................................................7

2.3.5 Menu overview...................................................................................................................8

3. Assembly and Installation....................................................................................9

3.1 Mounting the Unit........................................................................................................................ 9

3.2 Connection Diagram.................................................................................................................. 11

4. Normal Operation................................................................................................13

4.1 Measurement Mode .................................................................................................................. 13

5. Calibration Mode................................................................................................. 14

5.1 Entering Calibration Mode......................................................................................................... 14

5.2 Calibration ................................................................................................................................. 15

5.2.1 One-Point Calibration.......................................................................................................15

5.2.2 Two-Point Calibration....................................................................................................... 16

5.3 View Probe Condition................................................................................................................18

6. Setup Mode..........................................................................................................19

6.1 Enter Setup Mode .....................................................................................................................19

6.2 Electrode Offset Settings (OFS)................................................................................................ 20

6.3 Temperature Setting (SET °C°F) .............................................................................................. 21

6.4 Control Relay A / Relay B Settings (SP1/SP2) ......................................................................... 22

6.5 Controller Settings (CNTR) ....................................................................................................... 24

6.6 Current Output 1 Settings (CUR 1)........................................................................................... 27

6.7 Current Output 2 Settings (CUR 2)........................................................................................... 28

6.8 Wash Relay Settings (WASH)................................................................................................... 29

6.9 Configuration Settings (CNFG) ................................................................................................. 30

6.10 Calibration (CAL) sub-function..................................................................................................31

7. Relay Modes ........................................................................................................32

7.1 View Relay Set Points............................................................................................................... 32

7.2 Manual Relay Mode .................................................................................................................. 33

8. Technical Specifications ....................................................................................34

8.1 General Specifications ..............................................................................................................34

8.2 Specifications for Wall Mount Version....................................................................................... 36

8.3 Specifications for Panel Mount Version .................................................................................... 36

9. Accessories.........................................................................................................37

9.1 Replacement Unit......................................................................................................................37

9.2 Assembly Accessories .............................................................................................................. 37

10. General Information .........................................................................................38

10.1 Warranty.................................................................................................................................... 38

10.2 Packaging / Scope of delivery...................................................................................................38

10.3 Return of goods......................................................................................................................... 38

10.4 Guidelines for returning unit for repair.......................................................................................38

11. Appendices.......................................................................................................39

11.1 Appendix 1 – Replacing Fuse ................................................................................................... 40

11.2 Appendix 2 – Dissolved Oxygen Values ................................................................................... 41

11.3 Appendix 3 – Simple Explanation on the Function of Hysteresis..............................................42

11.4 Appendix 4 – General Instructions Concerning Controller Setting............................................ 43

11.5 Appendix 5 – Abbreviations Used in LCD................................................................................. 45

Instruction manual Alpha DO 2000

1. Introduction

1.1 Before You Begin

We thank you for purchasing the Alpha DO 2000.
The construction of the Alpha DO 2000 employs leading edge technology

and complies with safety regulations currently in force. Notwithstanding this,
improper use could lead to hazards for the user or a third-party, and/or
adverse effects on the plant or other equipment. Therefore, the operating

instructions must be read and understood by the persons involved
before work is started with the Alpha DO 2000.

Thermo Scientific do not accept any liability for damage that may arise
from neglecting information given in this manual.

This instruction manual identifies safety instructions and additional
information by means of the following symbols:

This symbol draws attention to safety instructions and warnings of
potential danger which, if neglected, could result in injury to persons
and/or damage to property.

This symbol identifies additional information and instructions which, if
neglected, could lead to inefficient operation and possible loss of
production.

The instruction manual must always be stored close at hand, in a place
accessible to all people working with the Alpha DO 2000.

If you have questions, which are not or insufficiently answered in this
instruction manual, please contact your supplier. They will be glad to assist
you.

1.2 Intended Use

The Alpha DO 2000 is intended solely for dissolved oxygen and temperature
measurement, as described in this instruction manual.

Any other use, or use not mentioned here, that is incompatible with the
technical specifications is deemed inappropriate. The operator is solely
responsible for any damage arising from such use.

Other prerequisites for appropriate use include:

− Comply with the instructions, notes and requirements set out in this
instruction manual.

− Comply with all local safety regulations concerning safety at work.

− Comply with all information and warnings in the documentation dealing

with the products used together with the transmitter (housings, sensors,
etc.).

− Comply with the prescribed environmental and operational conditions.

1

Instruction manual Alpha DO 2000

1.3 Safety Instructions

-The Alpha DO 2000 should be installed and operated only by personnel
familiar with the transmitter and who are qualified for such work.

- A defective transmitter must neither be installed nor put into service.

- The Alpha DO 2000 must only be operated under the specified operating
conditions

- The Alpha DO 2000 must not be repaired by the customer.

- The Alpha DO 2000 must only be opened to replace the unit fuse or to set
the jumper for Pt100/Pt1000 temperature sensor. This work must be carried
out only by personnel familiar with the transmitter and who are qualified for
such work. Make sure the mains cable is separated from the power supply
before opening the unit.

-No modifications to the Alpha DO 2000 are allowed. The
manufacturer/supplier accepts no responsibility for damage caused by
unauthorized modifications. The risk is borne entirely by the user.

1.4 Taking Out of Service / Correct Disposal of the Unit

Taking out of service

• First disconnect the unit from the mains, and then undo all electrical
connections.

• Remove the unit from the wall / panel.

Correct disposal of the unit

When the transmitter is permanently taken out of service, observe the local
environmental regulations for correct disposal or send the transmitter to your
local distributor, they will take care of proper disposal.

2

Instruction manual Alpha DO 2000

2. Getting Started

2.1 Description of Instrument

The Alpha DO 2000 is used for measuring dissolved oxygen (in % saturation,
mg/l or ppm) and temperature values. The dissolved oxygen values can be
measured using limit or P/PI control.

The transmitter is available in two versions, one for panel mounting and one
for wall mounting in a enclosure. The transmitter can be used for applications
such as water treatment and monitoring, chemical and food processing,
clean and wastewater control and fish farming.

This controller/transmitter has many user-friendly and safety features which
include:

• Menu-driven program that simplifies set-up

• Built-in non-volatile memory to ensure that calibration and other

information are not erased if power supply fails.

• Push-button for calibration and sensor offset adjustment from the keypad.

• Automatic temperature compensation (ATC).

• Manual temperature compensation setting without the ATC probe, with

independent setting for calibration and process temperature.

• Two galvanically isolated current outputs 0/4...20mA.

• 0 to 1999 seconds time delay adjustment on all relays – minimizes false

alarms.

• Separately adjustable high and low set-point hysteresis (dead bands)
prevent chattering of relays around the set points.

• Three control modes: limit controller, P controller and PI controller (P/PI
controller as pulse length or pulse frequency).

• Large dual display LCD for easy reading with clear multiple annunciators,
alarm status, operational and error messages.

• Two switching contacts as set-point relays.

• Separate alarm relay alerting you to set point limits exceeded for a certain

time and if the NTC wires are broken or disconnected during the ATC
function.

• Wash relay.

• Hold function to freeze output current (0/4...20mA) and release control

relays.

• LED indicators signal control activities to visually monitor transmitter
status from a distance.

• Protection against electromagnetic interference.

• Back lit and UV light protected LC display.

3

Instruction manual Alpha DO 2000

r

2.2 Measurement and Control System

A typical measurement system consists of:

• an Alpha DO 2000 PG dissolved oxygen controller/transmitter

• a dissolved oxygen sensor with integrated or separate temperature

sensor

• an appropriate measurement cable

• an immersion, flow or process assembly

• a final control element such as pump or valve

• a chart recorder

αlpha DO 2000WPG
Controller/Transmitte

Chart Recorder

Housing and
Sensors

Measurement Cable

0/4 - 20 mA

Alarm /Siren System

Power Mains

(80 - 250 V AC/DC)

4

Instruction manual Alpha DO 2000

2.3 Overview

Wall mounting version

Panel mounting version

5

Instruction manual Alpha DO 2000

2.3.1 Display Overview

The LC display shows two alpha-numerical fields for parameters and
measured values as well as various mode and status indicators.

SETUP

READY
HOLD

ERR

MEAS

-8.8.8.8

CAL

-8.8.8.8

2.3.2 Key Functions

Key Description

%

ppm
mg/l

°C °F

ATC

Mode indicators:

MEAS: measurement mode
SETUP: Setup mode
CAL: Calibration mode

Status indicator:

READY: Visible after successful calibration
HOLD: Relay position and current output are

frozen
ATC: Visible in ATC (Automatic Temperature

Compensation) mode. Not visible in the Manual
Temperature Compensation mode. “ATC”
flashes if the temperature probe is faulty in its
ATC mode

ERR: Error or alarm indicator

Enter Calibration mode (requires access code)

Enter Setup mode (requires access code)
Access sub functions (parameters) within a function group of Setup mode
Confirm (store) setup parameters and numerical values
Start/Confirm calibration in Calibration mode.

Select function group in the Setup mode.
Set parameters and numerical values (if key is pressed continuously, the setting

speed increases).
Control the relays in MANUAL relay operation.
Returns to “Measurement mode” when both keys are pressed simultaneously.

Display limit values for SP1 and SP2 and settings for wash contact in AUTO
relay operation.

Toggle between RELAY A, RELAY B or Wash relay in MANUAL relay operation
Toggle between AUTO & MANUAL relay operation modes. (requires access

code to switch to MANUAL relay operation mode)

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Instruction manual Alpha DO 2000

2.3.3 LED Indicators

Relay indicators

If REL key is pressed the LED (A, B or W) indicates to which Relay
(A, B or Wash) the displayed limit values refer.

Relay mode indicators

Auto LED lights if relay operation is set to automatic mode. Manu
LED lights if relay operation is set to manual mode.

Relay status indicators

LED lights if limit value is exceeded or the ATC probe fails.

LED lights green if measured value is within the limit for Relay A
LED lights red if measured value exceeds limit for Relay A.

LED lights green if measured value is within the limit for Relay B
LED lights red if measured value exceeds limit of Relay B

LED lights if cleaning cycle is on.

2.3.4 Security Codes

The access to Calibration mode, Setup mode and Manual relay operation
mode is protected with security codes. The security codes are set at the

factory and cannot be changed by the user. The following security codes are
used:

Security code Mode/Description

000 View only mode/ to view settings

11 Calibration mode/ to start calibration

22 Setup mode/ to configure parameters

22 Manual relay operation mode/ to switch to relay

operation mode from AUTO to MANUAL

7

Instruction manual Alpha DO 2000

2.3.5 Menu Overview

MEAS

%

13.0

CAL

1

ENT ENT

°C

1

CCD “000” = Chec k c al i bration par ameters (View only mode)

ENT

2

CCD “11” = Calibration mo de

2

SCD “000” = Check setup parameters (View only mode)
SCD “22” = Setup mode

SETUP

HOLD

SETUP

HOLD

OFS

ENT

ENT

Offset settings

see section 6.2

Temperature settings

see section 6.3

SETUP

HOLD

SETUP

HOLD

SETUP

HOLD

SETUP

HOLD

SETUP

HOLD

SETUP

HOLD

ENT

ENT

ENT

ENT

ENT

ENT

Relay A (set point 1) settings

see section 6.4

Relay B (set point 2) settings

see section 6.4

Controller settings

see section 6.5

Current output 1 settings

see section 6.6

Current output 2 settings

see section 6.7

Wash relay settings

see section 6.8

SETUP

HOLD

SETUP

HOLD

ENT

ENT

Configuration settings

see section 6.9

Calibration

see section 5

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Instruction manual Alpha DO 2000

3. Assembly and Installation

3.1 Mounting the Unit

Wall mount version

144 [5.67]

144 [5.67]

111.50 [4.39]

27.5 [1.08]

approx. 14 [.55]

21.5 [.85]

66.5 [2.62]

6 [.24]

Max.80

39 [1.54]
78 [3.07]

80 [3.15]

90 [3.54]

84 [3.30]

1-22 [0.03 - 0.87]

Pg13.5 (3 pcs.)

29 [1.14]

Holes for post
mounting (4X)

Holes for wall
mounting (2X)

90 [3.54]

Red Plugs for wall
mounting holes
enclosure (2X)

24 [.94]

For Pg13.5 cable glands

57.8[2.28]

175 [6.88]

Seal gasket

Threaded rod for pane l mounting

Environmental protection class: IP 66, NEMA 4X (housing)

Unit:
MM [INCH]

138 [5.43]

138 [5.43]

Cut-out mounting plates for post mounting

9

175 [6.88]

Instruction manual Alpha DO 2000

Panel mount version

Flat gasket 1mm [.04]

(to be inserted by customer )

Panel cut out

Unit: MM [INCH]

Environmental protection class: IP 54 (front), IP 40 (housing)

10

Instruction manual Alpha DO 2000

3.2 Connection Diagram

Wall mount version

Connections Description

1. AC mains live wire 14. Hold function

2. AC mains neutral wire 19. 12V output power supply

3. AC mains protective earth wire 20. 12V output ground

4. Alarm relay (NO) 21. Earth ground

5. Alarm relay common 22. DO input, Anode

6. Alarm relay (NC) 23. DO input, Cathode

7. Wash relay 24. Temperature – T2

8. Wash relay 25. Temperature – N.C

9. Relay B (SP 2) 26. Temperature – T1

10. Relay B (SP 2) 28. 4-20 mA temperature output, -ve

11. Relay A (SP 1) 29. 4-20 mA temperature output, +ve

12. Relay A (SP 1) 30. 4-20 mA DO output, -ve

13. Hold function 31. 4-20 mA DO output, +ve

Probe Cable Connections

Cable Connection

Colorless/Center (Cathode) K (23)
Brown (Anode) A (22)
Blue (T1) TEMP (26)
Yellow (T2) TEMP (24)
Green/Yellow (Cable Outer Shield) A (22)
Connect jumper wire From E(21) to A (22)

Controller/Transmitter
Terminal

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Instruction manual Alpha DO 2000

Panel mount version

Connections Description

1. AC mains live wire 14. Hold function

2. AC mains neutral wire 19. 12V output power supply

3. AC mains protective earth wire 20. 12V output ground

4. Alarm relay (NO) 21. Earth ground

5. Alarm relay common 22. DO input, Anode

6. Alarm relay (NC) 23. DO input, Cathode

7. Wash relay 24. Temperature – T2

8. Wash relay 25. Temperature – N.C

9. Relay B (SP 2) 26. Temperature – T1

10. Relay B (SP 2) 28. 4-20 mA temperature output, -ve

11. Relay A (SP 1) 29. 4-20 mA temperature output, +ve

12. Relay A (SP 1) 30. 4-20 mA DO output, -ve

13. Hold function 31. 4-20 mA DO output, +ve

Probe Cable Connections

Cable Connection

Colorless/Center (Cathode) K (23)
Brown (Anode) A (22)
Blue (T1) TEMP (26)
Yellow (T2) TEMP (24)
Green/Yellow (Cable Outer Shield) A (22)
Connect jumper wire From E(21) to A (22)

Controller/Transmitter
Terminal

12

Instruction manual Alpha DO 2000

4. Normal Operation

4.1 Measurement Mode

When the controller/transmitter is powered on, the display first shows all
segments briefly, and then the controller/transmitter automatically enters into
the Measurement mode.

Î NOTE:

The annunciators “%”, “mg/l” or “ppm” at the upper right side of the display
indicate the current measurement mode setting whether the transmitter is set
for %, mg/l or ppm measurement.

From Measurement mode you can access Calibration mode and Setup
mode by pressing the CAL key or ENT key followed by the corresponding
security code. For detailed information refer to section 5 “Calibration mode”
or section 6 “Setup mode”, respectively.

To guarantee accurate readings the measuring system (transmitter
and sensor) must be calibrated.

READY

MEAS

100.0

25.0

%

°C

ATC

The mode indicator “MEAS” at the top of
the display indicates that the transmitter
is in Measurement mode. The upper
alpha-numerical display shows the
measured dissolved oxygen value (in %,
mg/l or ppm), while the lower display
shows the temperature value (in °C or
°F)

By pressing the REL key in Measurement mode you can view the actual
relay set points. By pressing the MODE key followed by the corresponding
security code in Measurement mode you can switch relay operation mode
from automatic to manual. For detailed information refer to section 7 “Relay
Modes”.

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Instruction manual Alpha DO 2000

5. Calibration Mode

You can access the Calibration mode directly from the Measurement mode
by pressing the CAL key and entering the Calibration security code “11”.
Calibration mode may also be accessed via the Setup mode (see section

6.1).

5.1 Entering Calibration Mode

MEAS

13.0

CAL

%

°C

ENT

11

ENT

22

ENT

SETUP

HOLD

SETUP

HOLD

OFS

CAL

DO

ENT

1-point or 2-point Calibration

See section 5.2

ENT

While in Measurement mode press CAL key (direct access) or ENT key (access via
Setup mode).

• If CAL key was pressed: The display prompts you to enter the
calibration security code (CCD). Press ▲ or ▼ key to set the
calibration security code to “11”, and then press ENT key to confirm
the calibration security code.

• If ENT key was pressed: The display prompts you to enter the security
code (SCD). Press ▲ or ▼ key to set the security code to “22”. Press
ENT key to confirm the security code, and then press ▲ or ▼ key to
select the calibration sub-function.

Î NOTE:

The display shows “CAL DO”. To start calibration, refer to section 5.2.

To exit Calibration mode at any time press ▲ and ▼ keys
simultaneously (escape). The transmitter returns to the Measurement
mode and the old calibration values remain active. The calibration
security code automatically resets from “11” to “000” after the transmitter
returns to Measurement mode.

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Instruction manual Alpha DO 2000

5.2 Calibration

Calibration is always carried out in the units (%, mg/l or ppm) selected in the
Setup mode. The transmitter allows a 1-point or 2-point calibration for
dissolved oxygen.

5.2.1 One-Point Calibration

SETUP

HOLD

CAL

DO

CAL

Rh

3

%

ENT

CAL

HOLD

HOLD

HOLD

CAL

CAL

CAL

BAR

PRES

H9

PRES

PSI

PRES

4

4

SETUP

ENT ENT

HOLD

1.013

4

CAL

CAL

2

2

SETUP

ENT

HOLD

100

1

ENT

SETUP

HOLD

1-PT

SETUP

HOLD

2-PT

CAL

BAR

5

6

CAL

SETUP

READY
HOLD

65.3

SETUP

ENT

HOLD

100.0

1. Enter Calibration mode as described in section 5.1. The display shows “CAL
DO”. Press ENT key to start calibration.

2. The display shows “1-PT CAL” by default. If “2-PT CAL” is shown, use ▲ or
▼ keys to select one-point “1-PT CAL”. Press ENT key to confirm the 1-point

selection.

3. Press ▲ or ▼ key to set the relative humidity. Press ENT key to confirm.

4. Press ▲ or ▼ key to select the desired unit for barometric pressure (“BAR”,
“mmHG” or “PSI”). Press ENT key to confirm.

5. Press ▲ or ▼ key to set the barometric pressure according to the selected
unit in step 4. Press ENT key to confirm.

6. Put sensor in the calibration solution or air. The temperature compensated
sensor current (in nA) is displayed. The “CAL” and and electrode symbol

start flashing. Once the reading stabilizes, the flashing symbols disappear and
“READY” comes on. Press ENT key.

CAL

SAT

7

%

ENT

MEAS

SETUP

100.0

CAL

25.0

8

%

7. Default calibration values for saturation or concentration are shown. Press

▲or ▼key to select the desired saturation (“SAT %”) or concentration (“Con
ppm” or “Con mg/l”). Press ENTER key to confirm.

8.

The transmitter returns to the Measurement mode.

15

Instruction manual Alpha DO 2000

Î NOTES:

• If you entered the Calibration mode from the Setup mode, the transmitter will
return to the setup menu.

• If there is a calibration error the transmitter displays “ERR”. In this case, press
the ▲ and ▼ keys simultaneously (escape) to restart the calibration

beginning from step 1.

• When calibrating with manual temperature compensation, the transmitter
automatically changes from the preset process temperature to the calibration
temperature. After leaving the Calibration mode, the transmitter switches back
to the process temperature (for setting the calibration temperature and the
process temperature, see section 6.3).

5.2.2 Two-Point Calibration

SETUP

HOLD

CAL

DO

CAL

100

Rh

3

%

ENT

CAL

HOLD

CAL

HOLD

CAL

HOLD

CAL

BAR

PRES

H9

PRES

PSI

PRES

4

4

SETUP

ENT ENT

HOLD

1.013

4

CAL

CAL

2

2

SETUP

HOLD

ENT

1

ENT

SETUP

HOLD

1-PT

SETUP

HOLD

2-PT

CAL

BAR

5

SETUP

READY
HOLD

0.0

CAL

6

SETUP

ENT

HOLD

Yes

SETUP

HOLD

NO

CAL

CAL

0.0

0.0

7

7

SETUP

ENT

HOLD

2nd

CAL

PNT

8

SETUP

ENT

READY
HOLD

95.5

CAL

9

ENT

SETUP

HOLD

100.0

CAL

SAT

10

ENT

%

MEAS

SETUP

100.0

CAL

25.0

11

%

1. Enter Calibration mode as described in section 5.1. The display shows “CAL
DO”. Press ENT key to start calibration.

2. The display shows “1-PT CAL” by default. Use ▲ or ▼ keys to select “2-PT
CAL” (2-point calibration). Press ENT key to confirm the 2-point selection.

3. Press ▲ or ▼ key to set the relative humidity. Press ENT key to confirm.

16

Instruction manual Alpha DO 2000

4. Press ▲ or ▼ key to select the desired unit for barometric pressure (“BAR”,
“mmHG” or “PSI”I). Press the ENT key to confirm.

5. Press ▲ or ▼ key to set the barometric pressure according to the selected
unit in step 4. Press the ENT key to confirm.

6. Put sensor in zero point solution or nitrogen. The temperature compensated
sensor current for zero point (in nA) is displayed. The “CAL” and electrode

symbol start flashing. Once the reading stabilizes, the flashing symbols
disappear and “READY” comes on. Press ENT key.

7. Press ▲ or ▼ key to accept new zero current with “YES” or to reject the new
calibration value with “NO”. Press ENTER key to confirm your selection

Î NOTE:

Accepting the zero point will reset the zero offset settings made in OFS
menu.

8. The display shows “2ND PNT”. Press ENT key to proceed with the calibration
of slope.

9. Put sensor in the calibration solution or air. The temperature compensated
sensor current (in nA) for the second point will be displayed. The “CAL” and

electrode symbol start flashing. Once the reading stabilizes, the flashing
symbols disappear and “READY” comes on. Press ENT key.

10. Default calibration values for saturation or concentration are shown. Press ▲
or ▼ key to select the desired saturation (“SAT %”) or concentration (“Con
ppm” or “Con mg/l”). Press ENT key to confirm.

11. The transmitter returns to the Measurement mode.

Î NOTES:

• If you entered the Calibration mode from the Setup mode, the transmitter will
return to the setup menu.

• If there is a calibration error the transmitter displays “ERR”. In this case, press
▲ and ▼ keys simultaneously (escape) to restart the calibration beginning
from step 1.

• When calibrating with manual temperature compensation, the transmitter
automatically changes from the preset process temperature to the calibration
temperature. After leaving the Calibration mode, the transmitter switches back
to the process temperature (for setting the calibration temperature and the
process temperature, see section 6.3).

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Instruction manual Alpha DO 2000

5.3 View Probe Condition

The probe condition is an indication of its current working condition with
respect to its original condition. The probe condition is calculated and stored
in the controller each time calibration is done.

You can view probe condition without entering into calibration mode.

1

MEAS

%

89.5

24.5

CAL

ATC

2

000

C.CD

ENT

CAL

3

CAL

DO

ENT

ENT

0.0

95.5

4

CAL

CAL

5

ENT

100.0

1. While in Measurement mode press CAL key.

2. The display prompts you to enter the calibration security code (CCD). Leave
the security code at “000” (view only mode). Press ENT key.

3. The display shows “CAL DO”. Press ENT key.

4. The display shows the zero point current in nA. Press ENT key.

5. The display shows the current in nA for the second calibration point. Press
ENT key.

ENT

CAL

ADJ

6

%

6. The display shows the selected measuring range in %. Press ENT key to
return to the Measurement mode.

Î NOTE:

If no key is pressed for 30 seconds during the above steps, the
controller automatically returns to the Measurement mode.

18

Instruction manual Alpha DO 2000

6. Setup Mode

6.1 Enter Setup Mode

In the Setup mode the transmitter can be configured to your individual requirements.

ENT

MEAS

13.0

%

°C

1. While in Measurement mode press ENT key.

2. The display prompts you to enter the security code.
Set the security code with ▲ or ▼ key to:

− “SCD 22” if you want to change parameter
settings

− “SCD 000” if you only want to view parameter
settings (view only mode)

3. Press ENT key.

ENT

SETUP
HOLD

SETUP
HOLD

SETUP
HOLD

SETUP
HOLD

OFS

ENT

ENT

ENT

ENT

Offset settings

see section 6.2

Temperature settings

see section 6.3

Relay A (set point 1) settings

see section 6.4

Relay B (set point 2) settings

see section 6.4

Î NOTE:

SETUP
HOLD

SETUP

HOLD

SETUP
HOLD

SETUP
HOLD

SETUP
HOLD

SETUP
HOLD

DO

ENT

ENT

ENT

ENT

CAL

ENT

ENT

Controller settings

see section 6.5

Current output 1 settings

see section 6.6

Current output 2 settings

see section 6.7

Wash relay settings

see section 6.8

Configuration settings

see section 6.9

Calibration

see section 6.10

To exit Setup mode at any time press ▲ and ▼ keys simultaneously
(escape). The transmitter returns to the Measurement mode.

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Instruction manual Alpha DO 2000

6.2 Electrode Offset Settings (OFS)

The electrode offset settings allow you to zero the transmitter without a
sensor. The use of a simulator is recommended. For real zero calibration,
use the calibration procedure as described in section 5. If no simulator is
used, a 22 kΩ NTC must be connected to pins 24 and 25 of the terminal
connector on the backside of the unit (see section 3.2).

SETUP

HOLD

OFS

ENT

NO

0.0

OFS

0.0

ADJ

OFS

OFS

ENT

ENT

2

2

SETUP

ENT ENT ENT

HOLD

This screen will not be

visible if DO Unit of

Measurement is set to %

(In Configuration settings)

3

%

4

%

ENT

1

ENT

SETUP

HOLD

SETUP

HOLD

YES

SETUP

HOLD

SETUP

HOLD

0.0

SAL

5

ppt

SETUP

HOLD

SETUP

HOLD

SETUP

HOLD

ENT

BAR

PRES

H9

PRES

PSI

PRES

6

SETUP

HOLD

1.013

6

6

BAR

7

1. From the setup mode select the “OFS” screen and then press ENT key.

2. Selecting to modify offset value: By default, controller shows “NO OFS”.
Press ▲ or ▼ key to select “NO” or “YES” for offset adjustment.

− Select “NO OFS” to skip offset adjustment and move to the next step.

− Select “YES OFS” to perform offset adjustment.

Press ENT key to confirm your selection.

− If “YES OFS” was selected:

3. Selecting offset value: The display shows the offset from zero current of
the saturation or concentration. If this is within the range of -0.2 nA to 1.1 nA,
then the correction can be accepted. Press ENT key to confirm.

4. The display shows the offset. Press ENT key to confirm.

5. Setting salinity of the solution (SAL): This display only appears if the
measurement unit is set to “mg/l” or “ppm”. Press ▲ or ▼ key to set the
salinity of the solution. Press ENT key to confirm.

6. Setting the unit for pressure (PRES): Press the ▲ or ▼ key to set unit
(“BAR”, “mmHG”, “PSI”) of the barometric pressure. Press the ENT key to
confirm.

7. Setting barometric pressure: Press ▲ or ▼ key to set the barometric
pressure according to the selected unit in step 6. Press ENT key to confirm.

Continue with rest of the Setup procedures by pressing ▲ or ▼ key or return to
the Measurement mode by pressing ▲ and ▼ keys (escape) simultaneously.

20

Instruction manual Alpha DO 2000

Î NOTE:

The offset value is reset during 2-point calibration. See section 5 for full
calibration instructions.

6.3 Temperature Setting (SET °C°F)

SETUP

HOLD

1 2

ENT

SETUP

HOLD

SETUP

HOLD

°C

2

°F

SETUP

ENT ENT

HOLD

SETUP

ENT

HOLD

1. From the setup mode, select the “SET °C°F” screen and then press ENT key.

2. Selecting temperature unit: Press ▲ or ▼ key to select the desired
temperature unit “°C” or “°F”. Press ENT key to confirm your selection.

3. Enable/disable ATC mode: Press ▲ or ▼ key to enable (ATC ON) or
disable (ATC OFF) automatic temperature compensation. Press ENT key to
confirm your selection.

3

3

ENT

SETUP

HOLD

SETUP

HOLD

4 5

6

°C
ATC

ENT

ENT

SETUP

HOLD

ENT

− ATC disabled (ATC OFF):

For manual temperature compensation you can set the process and
calibration temperatures. This allows calibration at a temperature other
than the process temperature.

4. Setting the process temperature: Press ▲ or ▼ key to adjust the
process temperature in the upper display value (setting range: –9.9 to
125°C / 15 to 257 °F). Press ENT key to confirm process temperature.

5. Setting the calibration temperature: press ▲ or ▼ key to adjust the
calibration temperature in the upper display value (setting range: –9.9
to 125°C / 15 to 257 °F). Press ENT key to confirm the calibration
temperature.

− ATC enabled (ATC ON):

6. Setting the temperature offset: The display shows the current
temperature offset (upper display value) and the temperature currently
measured (lower display value). Compare the current temperature
displayed on the transmitter to a thermometer known to be accurate.
Note the correct temperature value. Press the ▲ or ▼ key to adjust the
lower display value. The upper number is automatically adjusted to the
offset value. You can offset the temperature by up to ±10°C/±18°F.
Press ENT key to confirm your setting.

The controller goes back to “SET °C°F” screen.

Continue with rest of the Setup procedures by pressing ▲ or ▼ key or return to
the Measurement mode by pressing ▲ and ▼ keys (escape) simultaneously.

21

Instruction manual Alpha DO 2000

6.4 Control Relay A / Relay B Settings (SP1/SP2)

The SP1 settings define the operating parameters for Relay A; while SP2
defines the operating parameters for Relay B. Since these two settings have
the same set-up parameters, only SP1 is described here.

SETUP

HOLD

1 2 3

ENT

SETUP

HOLD

SETUP

HOLD

SETUP

HOLD

SETUP

ENTENT ENT

HOLD

3

ENT

4 5

%

SETUP

HOLD

SETUP

HOLD

ENT

6

1. From the setup mode, select the “SP1” (Relay A) screen and then press ENT
key.

2. Setting set point value: Press ▲ or ▼ key to enter the value for set point 1
at which your controller will activate. Press ENT key to confirm your setting.

3. Selecting relay function: Press ▲ or ▼ key to select the desired relay
function (“LO”= low or “HI”= high). Press ENT key to confirm your selection.

Î NOTE:

This parameter lets you choose the relay function. Select “LO” to
activate the relay when the dissolved oxygen value undershoots the low
set point; select “HI” to activate the relay when the value overshoots the
high set point. SP1 and SP2 can be selected as “Lo/Lo”, “Lo/Hi”,
“Hi/Lo”, or “Hi/Hi”.

ENT

4. Setting a hysteresis value: Press ▲ or ▼ key to select the desired
hysteresis (setting range: 1 to 10% or 0.1 to 1.0 mg/l) for set point 1. Press
ENT key to confirm your setting.

Î NOTE:

Hysteresis prevents rapid contact switching if your value is fluctuating
near the set point. Please refer to Appendix 3 for a graphical
representation of the hysteresis.

Example: You have set your low set point at 6.20 mg/l and your hysteresis
value at 0.5 mg/l. If your measured value undershoots 6.20 mg/l, the
controller’s relay activates. The actions of the external device will cause the
value to rise above 6.20 mg/l. The relay will deactivate, when the DO value
has increased to 6.70 mg/l (6.20 + 0.50).

5. Setting the on-delay time lag: Press ▲ or ▼ key to enter the on-delay time
for set point 1. The controller will delay activation of the relay for the number of

22

Instruction manual Alpha DO 2000

seconds (0 to 1999 seconds) you select. Press ENT key to confirm your
setting.

Î NOTE:

You can set a time delay for each relay, which stops the relay from
switching on the moment the set point is exceeded. This controller lets
you set a 0 to 1999 seconds time delay before your relay activates.

6. Setting the off-delay time lag: press ▲ or ▼ key to enter the off-delay time
for set point 1. The controller will delay deactivation of the relay for the number
of seconds (0 to 1999 seconds) you select. Press ENT key to confirm your
setting.

Î NOTE:

You can set a time delay for each relay, which stops the relay from
switching off the moment the value reaches the set point and
hysteresis. This controller lets you set a 0 to 1999 seconds time delay
before your relay deactivates.

The controller goes back to “SP1” screen.
Continue with rest of the Setup procedures by pressing ▲ or ▼ key or return

to the Measurement mode by pressing ▲ and ▼ keys (escape)
simultaneously.

23

Instruction manual Alpha DO 2000

6.5 Controller Settings (CNTR)

The CNTR settings define the controller type and relay status the DO
controller.

SETUP

HOLD

1 2

SETUP

ENT ENT

HOLD

SETUP

HOLD

SETUP

HOLD

2

2

SETUP

ENT

HOLD

SETUP

HOLD

SETUP

ENT

HOLD

3

ENT

3

ENT

4

ENT

SETUP

HOLD

SETUP

HOLD

5

ENT

5

ENT

SETUP

HOLD

SETUP

HOLD

SETUP

HOLD

6 7 8

%

10 11 12

%

ENT

ENT

SETUP

HOLD

SETUP

HOLD

4

SETUP

ENT ENT

HOLD

SETUP

HOLD

SETUP

ENT

HOLD

SETUP

ENT

HOLD

9

9

ENT

ENT

ENT

24

Instruction manual Alpha DO 2000

1. From the setup mode, select the “CNTR” screen and then press ENT key.

2. Selecting the controller type (TYP): Press ▲ or ▼ key to select the
suitable controller type:

− OFF = controller off

Use control OFF to operate controller as a monitor only or to prevent
relays from switching. When the controller is set to OFF, all the LEDs
will be switch off in the Measurement mode

− L.CT = limit value control (on/off control).

Use limit control with pumps or valves for fast response

− P/PI = proportional/integral control

Use proportional control to operate your pumps smoothly or for precise
control of proportioning valves. Use PI controller to eliminate steady
state error.

Î NOTE:

Press ENT key to confirm your selection.

− If the controller is set to limit value control (L.CT):

3. Selecting the relay status under Non-Alarm condition (REL): Press ▲

− If the controller is set to proportional control (P/PI):

4. Selecting the proportional controller type (TYP): Press ▲ or ▼ key to

− If the proportional controller type is set to pulse length control (PLC):

Please refer to Appendix 3 for detailed information on controller
settings.

or ▼ key to choose the desired relay status (de-energized = “DEEN” or
energized = “EN”). Press ENT key to confirm your selection.

select the suitable controller type (“PLC” = pulse length control, “PFC” =
pulse frequency control). Press ENT key to confirm your selection.

5. Selecting the relay status under Non-Alarm condition (REL): Press
▲ or ▼ key to choose the desired relay status (de-energized = “DEEN”
or energized = “EN”). Press ENT key to confirm your selection.

6. Setting the proportional range (PRP): Press ▲ or ▼ key to set the
proportional range (setting range: 10 to 500%). Press ENT key to
confirm your setting.

7. Setting the pulse length (T.PL): Press ▲ or ▼ key to set the pulse
length (setting range: 0.5 to 20 seconds). Press ENT key to confirm
your setting.

8. Setting the integral action time (IAT): Press ▲ or ▼ key to set the
integral action time (setting range: 0.0 to 999.9 minutes). Press ENT
key to confirm your setting.

25

Instruction manual Alpha DO 2000

− If the proportional controller type is set to pulse frequency control (PFC):

9. Selecting the relay status under Non-Alarm condition (REL): Press
▲ or ▼ key to choose the desired relay status (de-energized =
“DEEN” or energized = “EN”). Press ENT key to confirm your selection.

10. Setting the proportional range (PRP): Press ▲ or ▼ key to set the
proportional range (setting range: 10 to 500%). Press ENT key to
confirm your setting.

11. Setting the pulse frequency (F.PF): Press ▲ or ▼ key to set the
pulse frequency (setting range: 60 to 120 pulses per minute). Press
ENT key to confirm your setting.

12. Setting the integral action time (IAT): Press ▲ or ▼ key to set the
integral action time (setting range: 0.0 to 999.9 minutes). Press ENT
key to confirm your setting.

The controller goes back to “CNTR” screen.
Continue with rest of the Setup procedures by pressing ▲ or ▼ key or return

to the Measurement mode by pressing ▲ and ▼ keys (escape)
simultaneously.

26

Instruction manual Alpha DO 2000

6.6 Current Output 1 Settings (CUR 1)

In this section, you set the current output range of the transmitter for
dissolved oxygen values.

SETUP

HOLD

1

SETUP

ENT ENT ENT ENT

HOLD

SETUP

HOLD

2

2

SETUP

HOLD HOLD

SETUP

ENT ENT ENT

HOLD HOLD

3

%

3

%

SETUP

SETUP

4

%

4

%

SETUP

HOLD

SETUP

HOLD

5

5

1. From the setup mode, select the “CUR 1” screen and then press ENT key.

2. Selecting the output type: Press the ▲ or ▼ key to select the desired
output type: 0-20 mA or 4-20 mA. Press ENT key to confirm your selection.

3. Setting the dissolved oxygen value at which the transmitter output will
be 4 mA (or 0 mA): Press ▲ or ▼ key to set the dissolved oxygen value to
be equivalent to 4 mA or 0 mA, respectively. Press ENT key to confirm your
setting.

4. Setting the dissolved oxygen value at which the transmitter output will
be 20 mA: Press ▲ or ▼ key to set the dissolved oxygen value to be
equivalent to 20 mA. Press ENT key to confirm your setting.

ENT

ENT

5. Selecting out of range current: Press the ▲ or ▼ key to switch “CU22” on
or off. If “CU22” is on, the output signal will jump to 22 mA, when the
measured DO value is below or above the values set in step 3 & 4 above.
Press ENT key to confirm your setting.

Î NOTE:

The “CU22” setting (on/off) of current output 1 applies to current output 2
as well.

The controller goes back to “CUR 1” screen.
Continue with rest of the Setup procedures by pressing ▲ or ▼ key or return

to the Measurement mode by pressing ▲ and ▼ keys (escape)
simultaneously.

27

Instruction manual Alpha DO 2000

6.7 Current Output 2 Settings (CUR 2)

In this, you set the current output range of the transmitter for temperature
values.

SETUP

HOLD

1 2

SETUP

ENT ENT ENT

HOLD

SETUP

HOLD

2

SETUP

HOLD HOLD

SETUP SETUP

ENT ENT

HOLD HOLD

3

°C

3

°C °C

SETUP

4

ENT

°C

4

ENT

1. From the setup mode, select the “CUR 2” screen and then press ENT key.

2. Selecting the output type: Press ▲ or ▼ key to select the desired output
type: 0-20 mA or 4-20 mA. Press ENT key to confirm your selection.

3. Setting the temperature value at which the transmitter output will be 4
mA (or 0 mA): Press ▲ or ▼ key to set the temperature value (setting range:

-9.9 to 115°C or 15 to 237 °F) to be equivalent to 4 mA (or 0 mA). Press ENT
key to confirm your setting.

4. Setting the temperature value at which the transmitter output will be 20
mA: Press ▲ or ▼ key to set the temperature value (setting range: -0.1 to
125°C or 35 to 257 °F) to be equivalent to 20 mA. Press ENT key to confirm
your setting.

The controller goes back to “CUR 2” screen.
Continue with rest of the Setup procedures by pressing ▲ or ▼ key or return

to the Measurement mode by pressing ▲ and ▼ keys (escape)
simultaneously.

28

Instruction manual Alpha DO 2000

6.8 Wash Relay Settings (WASH)

In this section, you set the parameters for the wash relay.

SETUP

HOLD

1 2

SETUP

ENT ENT ENT

HOLD

SETUP

HOLD

2

ENT

SETUP SETUP

HOLD HOLD HOLD

SETUP

HOLD

3

3

ENT

4 5

SETUP

ENT ENT

1. From the setup mode, select the “WASH” screen and then press ENT key.

2. Enabling/disabling wash function: Press ▲ or ▼ key to enable (WASH ON)
or disable (WASH OFF) wash function. Press ENT key to confirm your
selection.

− If “WASH OFF” was selected, the transmitter returns “WASH” sub-function.

− If “WASH ON was selected:

3. Selecting the relay status condition: Press ▲ or ▼ key to
choose desired relay status (de-energized = “DEEN” or
energized = “EN”). Press ENT key to confirm your selection.

Î NOTE:

The controller goes back to “WASH” screen.
Continue with rest of the Setup procedures by pressing ▲ or ▼ key or return

to the Measurement mode by pressing ▲ and ▼ keys (escape)
simultaneously.

4. Setting the wash interval in hours: Press ▲ or ▼ key to set
the desired wash interval (setting range: 0.1 to 199.9 hours).
Press ENT key to confirm your setting.

5. Setting the wash duration in seconds: Press ▲ or ▼ key to
set the desired wash duration (setting range: 1 to 1999
seconds). Press ENT key to confirm your setting.

During wash cycle the transmitter is set to HOLD. For safety reasons,
the HOLD function is activated 5 seconds prior and deactivated 10
seconds after the wash cycle.

29

Instruction manual Alpha DO 2000

6.9 Configuration Settings (CNFG)

In this section, you configure the transmitter to suit your requirements.

SETUP

HOLD

1

ENT

SETUP

HOLD

SETUP

HOLD

2

2

SETUP

ENT ENT ENT

ENT

HOLD

3

SETUP

HOLD

SETUP

HOLD

UNIT

UNIT

DO

DO

4

mg/l

SETUP

HOLD

4

ppm

5

ENT

DO

4

%

S

HOLD

ETUP

SETUP

HOLD

UNIT

6

SETUP

ENT ENT

HOLD

8

SETUP

HOLD

6

ENT

SETUP

HOLD

SETUP

HOLD

CAL

FCT

8

ENT

8

ENT

MEAS

31.0

%

°C
ATC

1. From the setup mode, select the “CNFG” screen and then press ENT key.

2. Enabling/disabling the display backlight: Press ▲ or ▼ key to switch
display backlight on (BKLT ON) or off (BKLT OFF). Press ENT key to confirm
your selection.

3. Setting the backlight intensity (appears only If backlight is on): Press ▲ or

▼ key to set backlight intensity (setting range: minimum 1 to maximum 4).
Press ENT key to confirm your setting.

4. Selecting the DO unit of measurement: Press ▲ or ▼ key to select DO
measurement unit (“mg/l” or “ppm” or “%”). Press ENT key to confirm your
selection.

5. Setting the alarm delay time: Press ▲ or ▼ key to set the alarm delay time
(setting range: 0 to 1999 seconds). Press ENT key to confirm your setting.

Î NOTE:

With this parameter you set the delay before the alarm relay activates
when the set point has been overshoot.

30

Instruction manual Alpha DO 2000

6. Selecting the alarm contact type: Press ▲ or ▼ key to select the alarm
contact type:

− “STDY” = steady contact

− “FLET” = fleeting (single pulse) contact

Press ENT key to confirm your selection.

Î NOTE:

7. Resetting the transmitter settings to factory defaults: The display shows

With this parameter you select whether the alarm contact will operate as
a steady contact or a fleeting (single pulse) contact. Pulse contact
closing time is 1 second.

“NO DEF”. Press ▲ or ▼ key to select:

− “NO DEF” = keeps user configured values active, when confirmed with

ENT key

− “FCT DEF” = resets all settings to factory defaults, when confirmed with

ENT key

− “CAL DEF” = resets all calibration settings to factory defaults, when

confirmed with ENT key

Press ENT key to confirm your selection.

− If “NO DEF” was selected, the transmitter returns “CNFG” screen.

Continue with rest of the Setup procedures by pressing ▲ or ▼ key, or
return to Measurement mode by pressing ▲ and ▼ keys (escape)
simultaneously.

− If “FCT DEF” or “CAL DEF” was selected, the selected function will be
executed and the transmitter returns automatically to the Measurement
mode.

6.10 Calibration (CAL)

The calibration procedure in Setup mode is identical to the procedure in the
Calibration mode (see section 5). The only difference is that the transmitter
remains in Setup mode (instead of Measurement mode) after calibration is
completed.

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Instruction manual Alpha DO 2000

7. Relay Modes

You can control devices connected to Relay A, Relay B or wash relay via the
front panel of the transmitter. In Automatic mode, the transmitter’s set point
values activate the relays. In Manual mode, you can manually turn “on” and
“off” the control devices connected to the relay A or relay B.

7.1 View Relay Set Points

To view relay set points, the relay mode must be set to automatic (standard
mode after switch-on, relay mode LED “Auto” lights).

While in Measurement mode, press the REL key.

%

60.0

SP1

%

40.0

Sp2

The display shows the relay set point value for Relay A
and LED “A” lights. (The mode of the relay set point will
be with respect to the measurement mode before REL
key is pressed).

After two seconds the display shows the set point value
for Relay B and LED “B” lights).

After two seconds the display shows the status of the
Wash relay and LED “W” lights. If Wash relay is “off” the
display shows “WASH OFF”. If Wash relay is “on” the
wash interval time and wash duration is displayed.

After an additional two seconds the transmitter will
return to Measurement mode.

32

Instruction manual Alpha DO 2000

7.2 Manual Relay Mode

In manual relay mode, you can manually turn “on” and “off” the control
devices connected to Relay A, Relay B or Wash relay.

1. While in Measurement mode press MODE key.

2. The display prompts you to enter the security code. Press ▲ or ▼ key to set
security code to “22”.

3. Press ENT key. The Manual relay mode is activated and the relay mode LED
“Manu” lights.

Î NOTE:

4. Press REL key to select either Relay A, Relay B or Wash relay. The

MEAS

31.0

MEAS

31.0

MEAS

31.0

Pressing ENT key at a value other than “22” will cause the transmitter
to revert to Measurement mode, and the relays will remain in
automatic mode.

corresponding LED (A, B, or W) turns to red.
The manual control options now available depend on the control type (limit,

pulse frequency, or pulse length) you selected and set in section 6.5.

%

%

%

If you selected Limit control: The display shows the
current measured value (in upper display) and “OFF” or
“ON” (in lower display) depending on the relay status of
the currently selected relay.

If you selected Pulse length control: The display shows
the current measured value (in upper display) and the on
time (in lower display) as a percentage of the current
duration set in the CNTR sub-function in setup mode.

If you selected Pulse frequency control: The display
shows the current measured value (in upper display)
and the pulse frequency (in lower display).

Press the ▲ or ▼ key to change the Relay on/off status, pulse length, pulse
frequency or wash function. The relay status LED at the right of the transmitter will
also change from Red to Green.

Î NOTE:

Press the MODE key to return to Measurement mode. The relays are now back to

automatic control.

Note: If you wish to manually change the status of relays, press the REL
key at this point and repeat step 5 for the other two relays. The relay(s)
will remain under manual control while you are setting a relay.

33

Instruction manual Alpha DO 2000

8. Technical Specifications

8.1 General Specifications

Dissolved Oxygen

Measuring range 0.00 to 20.00 mg/l or ppm

0.0 to 200.0 %

Resolution 0.01 mg/l or ppm or

0.1 %

Relative accuracy ±1 % of full-scale reading

Temperature

o

Measuring range -9.9 to +125.0

+15.0 to +257.0

o

0.1

C or

o

F

Resolution 0.1

C or

o

F

Relative accuracy ±0.5oC or

o

±1.0

F

Sensor NTC 22 kΩ thermistor

Compensation

Temperature Compensation Automatic or Manual
Salinity Compensation 0.0 to 50.0 ppt

(Manual setting and automatic correction)

Pressure Compensation 0.740 to 3.000 bar

555 to 2250 mmHg

10.73 to 43.51 PSI
(Manual setting and automatic correction)

Set-point and Control Function

Function Switchable Off

Limit Control
P/PI Control (Pulse length / Pulse

frequency)
Integral Action Time (IAT) 0.0 to 999.9 minutes
Adjustable period with pulse length

0.5 to 20 seconds
controller
Adjustable period with pulse

60 to 120 pulses/min
frequency controller
Pickup / Dropout delay 0 to 2000 seconds
Wash cycle 0.1 to 200.0 hours
Wash duration 1 to 2000 seconds
Switching DO hysteresis 0.1 to 1.0 mg/l or 1.0 to 10.0 %
Contact outputs, controller 1 SPDT, 3 SPST relays
Switching voltage max. 250 VAC
Switching current max. 3A
Switching power max. 600 VA

34

Instruction manual Alpha DO 2000

Alarm Functions

Function (switchable) Latching or pulse
Pickup delay 0 to 2000 seconds
Switching voltage max. 250 VAC
Switching current max. 3A
Switching power max. 600 VA

Display

LCD UV coat, backlit 14 segments display with

symbols for status information
Back light On/Off selectable with four levels of brightness

control

EMC Specifications

Emissions EN 61326
Susceptibility EN 61326

Environmental Conditions

o

Ambient Temperature operating

0 to +50

C
range
Relative Humidity 10 to 95%, non-condensing

35

Instruction manual Alpha DO 2000

8.2 Specifications for Wall Mount Version

Electrical Data and Connections

Power requirements 80 to 250 V AC/DC
Frequency 48 to 62 Hz
Signal output Two 0/4 to 20 mA outputs for DO values and

temperature, galvanically isolated
Load max. 600 Ω
DO input screw terminals
Connection terminal 2x3-pin, 8-pin, 9-pin and 13-pin terminal blocks
Mains fuse 250 mA anti surge

Mechanical Specifications
Dimensions (L x H x W) 144 x 144 x 110 mm
Weight 950 g
Material PBT
Insulation NEMA 4X, IP 65

8.3 Specifications for Panel Mount Version

Electrical Data and Connections

Power requirements 80 to 250 V AC/DC
Frequency 48 to 62 Hz
Signal output Two 0/4 to 20 mA outputs for DO values and

temperature, galvanically isolated
Load max. 600 Ω
DO input screw terminals
Connection terminal 3-pin, 9-pin and 19-pin terminal blocks
Mains fuse 250 mA anti surge

Mechanical Specifications
Dimensions (L x H x W) 175 x 96 x 96 mm
Weight 700 g
Material ABS
Insulation IP 54 (front) / IP 40 (housing)

36

Instruction manual Alpha DO 2000

9. Accessories

9.1 Replacement Unit

Product Description

Alpha DO 2000 Controller / Transmitter,
wall mount version

Alpha DO 2000 Controller / Transmitter,
panel mount version

Eutech Instruments

Order Code

ECDOCTP2000WPG TSDOCTP2000WPG

ECDOCTP2000PPG TSDOCTP2000PPG

Thermo Scientific

Order Code

9.2 Other Accessories

Product Description Order Code

Amperometric Dissolved Oxygen Probe EC237150
Fermentation Dissolved Oxygen Probe EC237450
Membrane Kit for EC237450 EC237140

Electrolyte for EC237450 EC237118
Connector Cap for EC237450 EC237137
Cable for EC237450, 5m EC355089
Cable for EC237450,10m EC355136
Panel Mount Kit for Alpha 2000 01X278701

Î NOTE:

Please contact your authorised distributor or dealer for the prices of extension measuring
cables and other accessories such as T-joints, electrode assembly, and calibration solutions.

37

Instruction manual Alpha DO 2000

10. General Information

10.1 Warranty

This Controller transmitter is supplied with a one-year warranty against
significant deviations in material and workmanship from date of purchase and
a six-month warranty for probe. Each instrument will have a warranty card
with a specific serial number. The warranty card must be endorsed by the
Authorized Distributor at the point of sale.
If repair or adjustment is necessary and has not been the result of abuse or
misuse within the designated period, please return – freight pre-paid – and
correction will be made without charge. Thermo Scientific/ Eutech will
determine if the product problem is due to deviations or customer misuse.
Out of warranty products will be repaired on a charged basis.

Exclusions

The warranty on your instrument shall not apply to defects resulting from:

• Improper or inadequate maintenance by customer

• Unauthoriz ed modification or misuse

• Operation outside of the environment specifications of the products

10.2 Packaging / Scope of delivery

The instrument is packaged in a corrugated box with an instruction manual
and the following accessories:

Wall mount version:

• Plug, nylon, red, 2 pcs

• PG13.5, cable gland, 3 pcs

• Connectors, one each of 3 way (5.08 mm), 9 way (5.08 mm), 13 way

(3.5mm), 8 way (3.5mm). 3 way (3.55mm)

Panel mount version:

• Rubber gasket, 1pc

• Catch, 2pcs

• Rod, threaded, 2 pcs

• Connector, one each of 19 way (3.5 mm), 3 way (5.08 mm) and 9way

(5.08 mm)

10.3 Return of goods

Authorization must be obtained from our Customer Service Department or
authorized distributor before returning items for any reason. A “Return
Goods Authorization” (RGA) form is available through our authorized
distributor. Please include data regarding the reason the items are to be
returned. For your protection, items must be carefully packed to prevent
damage in shipment and insured against possible damage or loss. Thermo

38

Instruction manual Alpha DO 2000

Scientific will not be responsible for damage resulting from careless or
insufficient packing. A restocking charge will be made on all unauthorized
returns.
NOTE: Thermo Scientific reserves the right to make improvements in
design, construction, and appearance of products without notice.

10.4 Guidelines for returning unit for repair

Use the original packaging material if possible when shipping the unit for
repair. Otherwise wrap it with bubble pack and use a corrugated box for
additional protection. Include a brief description of any faults suspected for
the convenience of Customer Service Dept., if possible.

39

Instruction manual Alpha DO 2000

11. Appendices

11.1 Appendix 1 – Replacing Fuse

Caution! Before opening the unit to replace the unit fuse, make sure the

Wall mount version (view from the backside)

mains cable is separated from the power supply.

Fuse: 250V,

Left

Panel mount version (view from top)

Rear Front

Right

40

Instruction manual Alpha DO 2000

11.2 Appendix 2 – Dissolved Oxygen Values

The following table shows the Dissolved Oxygen values at different salinity
values, at different temperatures, at barometric pressure of 760 mmHg. For
other pressure levels, the controller automatically corrects the value based
on the pressure value input.

Temperature Salinity- ppt

o

C

0 32.0 14.6 13.8 13.0 12.1 11.3
1 33.8 14.2 13.4 12.6 11.8 11.0
2 35.6 13.8 13.1 12.3 11.5 10.8
3 37.4 13.4 12.7 12.0 11.2 10.5
4 39.2 13.1 12.4 11.7 11.0 10.3
5 41.0 12.7 12.1 11.4 10.7 10.0
6 42.8 12.8 11.8 11.1 10.5 9.8
7 44.6 12.1 11.5 10.9 10.2 9.6
8 46.4 11.8 11.2 10.6 10.0 9.4

9 48.2 11.5 11.0 10.4 9.8 9.2
10 50.0 11.3 10.7 10.1 9.6 9.0
11 51.8 11.0 10.5 9.9 9.4 8.8
12 53.6 10.7 10.3 9.7 9.2 8.6
13 55.4 10.5 10.1 9.5 9.0 8.5
14 57.2 10.3 9.9 9.3 8.8 8.3
15 59.0 10.1 9.7 9.1 8.6 8.1
16 60.8 9.8 9.5 9.0 8.5 8.0
17 62.6 9.6 9.3 8.8 8.3 7.8
18 64.4 9.4 9.1 8.6 8.2 7.7
19 66.2 9.2 8.8 8.5 8.0 7.6
20 68.0 9.1 8.7 8.3 7.8 7.4
21 69.8 8.9 8.6 8.1 7.7 7.3
22 71.6 8.7 8.4 8.0 7.6 7.1
23 73.4 8.6 8.3 7.9 7.4 7.0
24 75.2 8.4 8.1 7.7 7.3 6.9
25 77.0 8.2 8.0 7.6 7.2 6.7
26 78.8 8.1 7.8 7.4 7.0 6.6
27 80.6 8.0 7.7 7.3 6.9 6.5
28 82.4 7.8 7.6 7.1 6.8 6.4
29 84.2 7.7 7.4 7.0 6.6 6.3
30 86.0 7.6 7.3 6.9 6.5 6.1
31 87.8 7.4 7.1 6.7 6.4 6.0
32 89.6 7.3 7.0 6.6 6.3 5.9
33 91.4 7.2 6.9 6.5 6.2 5.8
34 93.2 7.1 6.8 6.5 6.1 5.7
35 95.0 7.0 6.7 6.4 6.0 5.6
36 96.8 6.8 6.5 6.2 5.9 5.5
37 98.6 6.7 6.4 6.1 5.8 5.4
38 100.4 6.6 6.3 6.0 5.7 5.3
39 102.2 6.5 6.3 5.9 5.6 5.2
40 104.0 6.4 6.3 5.8 5.5 5.2

o

F 0 10 20 30 40

41

Instruction manual Alpha DO 2000

O

11.3 Appendix 3 – Simple Explanation on the Function of
Hysteresis

SP1 = 4.00 mg/l & Set to L
SP2 = 6.00 mg/l & Set to HI

RELAY ON

4.00

SP1

Default = 0.2 mg/l

HYSTERESIS BAND

4.20

RELAY OFF

5.80 6.00

Forward Direction
Reverse Direction

Default = 0.2 mg/l

HYSTERESIS BAND

Mg/l

SP2

The controller relay activates when the set-point is reached. In the reverse
direction, it does not de-activate when the value reaches the set-point.
Instead, it continues to be active till the value reaches the amount set by the
Hysteresis band.

42

Instruction manual Alpha DO 2000

11.4 Appendix 4 – General Instructions Concerning
Controller Setting

Control characteristic of Controllers used as limit value switch

MIN function MAX function

-Xw

Xp = 0

100% Yh

50%

0%

SP 2SP 1

Xp = 0

Control characteristic of P-Controllers as proportional controller

MIN function MAX function

100% Yh

+Xw

-Xw

50%

0%

Xp

Prop. band Prop. band

SP 1

Xp

SP 2

43

+Xw

Instruction manual Alpha DO 2000

Control signal of pulse length controllers

Relay

Pulse Length T

tON

ON

tOFF

OFF

The output relay of the pulse length controller is clock-timed. The switching period T
remains constant. Depending on the divergence from the limit value, the switch on
time tON is increased or decreased in accordance with the proportional range Xp.

The following applies:

tON + tOFF = T (Const.)
greater divergence Î greater tON
Xp exceeded Î tON = T (relay remains picked up)

Control signal of Pulse Frequency Controllers

Relay

Pulse Length T

tON

ON

tOFF

Time [s]

OFF

Time [s]

The output relay of the pulse frequency controller is clock-timed. The pulse duration
tON remains constant at 250 msec. Depending on the divergence from the limit
value, the frequency (1/T) is increased or decreased in accordance with the
proportional range Xp.

The following applies:

tON = Const. (250 msec.)
greater divergence Î greater f (greater frequency)
Xp exceeded Î max. frequency

44

Instruction manual Alpha DO 2000

11.5 Appendix 5 – Abbreviations Used in LCD

Abbreviation Description Abbreviation Description

nA Nano-ampere
AL.D Alarm delay OFS Offset
ATC Automatic

temperature
compensation ON.D On delay
BAR Pressure in bar OUT Output signal
BKLT Back light P. ºC Process temperature

C.ºC
CAL Calibration PLC Pulse length control

CAL DEF Calibration default PNT Point
CCD
CNFG Configuration PRES Barometric pressure

CNTR Controller PRP Proportional range
Con Concentration PSI Ponds per square inch

CU22
CUR 1 Output current 1 RH Relative humidity

CUR 2 Output current 2 R.0 0 mA Output current
DEEN Deenergized R.4 4 mA Output current
EN Energized R.20 20 mA Output current
ENT Enter SAL Salinity
FCT DEF Factory default SAT Saturation
FLET Fleet, impulse SCD Setup security code

F.PF Pulse frequency
HI High limit SET Setting
H.INT
HYS Hysteresis SP2 Setpoint 2

IAT Integral action time STDY Steady
L.CT Limit control T.PL Pulse length time

LEVL
LO Low limit UNIT measuring unit

MANU Manual WASH Wash
MEAS Measurement 1-PT One-Point

mmHg

Calibration

temperature

Calibration security

code

Out of range current

22mA

Wash interval in

hours

Back light intensity

level

Pressure in mm

mercury

OFF.D Off delay

PFC Pulse frequency control

P/PI Proportional/integral

control

REL Relay

S.DUR

SP1 Setpoint 1

TYP Type

2-PT Two-Point

Wash duration in
seconds

45

Water Analysis Instruments

North America

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Tel: [phone]
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#04-16/24, Singapore 139949
Tel: [phone]
Fax: [phone]

www.thermo.com/process

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All rights reserved. Thermo Fisher Scientific Inc.

68X216879 Rev 3