ABB 9408 750, Instruction Manual

1

The ABB Model 9408 Floating Ball is a dissolved oxygen
measuring system primarily for use in sewage treatment works
where fouling of the dissolved oxygen sensor by rags or other
large solids is a common occurrence.

To prevent this contamination, a flat ended sensor is mounted
inside a relatively large diameter flotation collar, and therefore
presents a surface to the contaminant upon which it is almost
impossible for the contaminant to collect.

Two other systems are available:

• dip
• submersible

which are for use in open tanks and where access is difficult.
See below for a list of variations.

All measuring systems are compatible with the 4640 and 4645
dissolved oxygen transmitters.

A water wash option is available on all dissolved oxygen
systems described in this manual. Optional items are shown in
illustrations as dotted lines.

Information.  To  enable easy access to the floating ball
sensor a conversion kit is available which converts the
standard bracket into a swivel bracket – see appendix for
ordering and conversion information.

The following systems are currently available:

Floating Ball

Assembled

Standard ............................................................... 9408 700
With water wash ................................................... 9408 702

Metric kit

Standard ............................................................... 9408 750
With water wash ................................................... 9408 752

Imperial kit

Standard ............................................................... 9408 760
With water wash ................................................... 9408 762

Dip

Assembled
Standard ........................................................ 9408 710 (1 m)

9408 720 (2 m)
9408 730 (3 m)

With water wash ............................................ 9408 712 (1 m)

9408 722 (2 m)
9408 732 (3 m)

Imperial kit

Standard ............................................................... 9408 771
With water wash ................................................... 9408 773

Submersible

Standard ................................................................. 9408 600
With water wash ..................................................... 9408 602

CONTENTS

1

INTRODUCTION

1

INTRODUCTION .......................................... 1

2

SYSTEM TYPES .......................................... 2

2.1

Unpacking ......................................................... 2

2.2

Floating Ball System .......................................... 2

2.2.1

Assembled Version ................................ 2

2.2.2

Kit Version ............................................. 2

2.3

Dip Systems ...................................................... 3

2.3.1

Assembled Version ................................ 3

2.3.2

Kit Version ............................................. 3

2.4

Submersible System ......................................... 3

3

MECHANICAL INSTALLATION ................... 4

3.1

Assembling Kit Systems .................................... 4

3.1.1

Floating Ball ........................................... 4

3.1.2

Dip ......................................................... 5

3.2

Installation ......................................................... 6

3.2.1

Floating Ball System .............................. 6

3.2.2

Dip Systems .......................................... 7

3.2.3

Submersible  Systems ........................... 7

3.3

Water Supply for Water Wash Systems ............ 8

4

ELECTRICAL INSTALLATION .................... 9

4.1

Connection to the Dissolved Oxygen

Transmitter ........................................................ 9

4.2

Calibrating the Sensor ....................................... 9

5

MAINTENANCE ......................................... 10

5.1

Replacing the Oxygen Sensor Capsule .......... 10

5.1.1

Floating Ball System ............................ 10

5.1.2

Dip Systems ......................................... 11

5.1.3

Submersible Systems ........................... 11

5.2

Replacing the Oxygen Sensor Block ................ 11

5.2.1

Floating Ball System ............................. 11

5.2.2

Dip Systems ......................................... 11

5.2.3

Submersible Systems .......................... 12

5.3

Changing the Temperature Compensator ....... 12

5.3.1

Floating Ball and Dip Systems ............ 12

5.3.2

Submersible System ........................... 12

6

SPECIFICATION ........................................ 12

7

SPARE PARTS LIST .................................. 13

7.1

Floating Ball System ........................................ 13

7.2

Dip System ...................................................... 13

7.3

Submersible System ....................................... 13

APPENDIX A – SUPPORT BRACKET

CONVERSION .......................................... 14

A1

Kit Parts List ..................................................... 14

A2

Conversion Procedure ..................................... 14