Rosemount OCX 8800 O2 / Combustibles Transmitter General Purpose with Remote Electronics-Rev 1.3 Manuals & Guides

Reference Manual

00809-0300-4880, Rev AA

July 2018

Rosemount

OCX 8800 Oxygen and

Combustibles Transmitter

General Purpose Probe with Remote Electronics

TM

Reference Manual

4880, Rev AA

July 2018

OCX 8800

TOC-2

00809-0300-

SECTION 1
Description and
Specifications

SECTION 2
Installation

SECTION 3
Configuration and
Startup

Table of Contents

Essential Instructions ........................................................................................ i

Preface ............................................................................................................... ii

Definitions .......................................................................................................... ii

Symbols .............................................................................................................. ii

Component Checklist ................................................................................... 1-1

System Overview .......................................................................................... 1-1

Specifications ..............................................................................................1-12

Mechanical

Installation ...................................................................................................... 2-2

Electrical Installation ..................................................................................... 2-8

Pneumatic Installation ................................................................................2-14

Initial Startup ................................................................................................2-20

Verify Installation ........................................................................................... 3-1

Initial Power Up ............................................................................................. 3-3

Set Test Gas Values .................................................................................... 3-4

OCX 8800 Reset Procedure ....................................................................... 3-4

SECTION 4
Using HART
Communications

SECTION 5
Calibration

SECTION 6
Maintenance and Service

Overview ........................................................................................................ 4-1

Field Communicator Sig na l Conn ec tio ns .................................................. 4-1

Field Communicator PC Connections ........................................................ 4-4

HART Menu Tree .......................................................................................... 4-5

D/A Trim Procedures .................................................................................... 4-9

Overview ........................................................................................................ 5-1

Fully Automatic Calibration .......................................................................... 5-1

Operator - Initiated Autocalibration ............................................................ 5-3

Manual Calibration ........................................................................................ 5-3

Overview ........................................................................................................ 6-1

OCX 8800 Removal

and Installation .............................................................................................. 6-1

OCX with

Remote Electronics ................................................................................. 6-2

Repair Sensor Housing ................................................................................ 6-8

Sensor Housing Disassembly ............................................................... 6-8

Sensor Housing Assembly .................................................................. 6-18

Repair Electronics Housing ...................................................................... 6-28

Electronics Housing Disassembly ..................................................... 6-28

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Electronics Housing Assembly ........................................................... 6-30

Replace Tube Fittings ................................................................................6-34

Remove Tube Fittings ..........................................................................6-34

Install Tube Fittings ...............................................................................6-35

SECTION 7
Troubleshooting

SECTION 8
Replacement Parts

APPENDIX A
Safety Data

APPENDIX B
SPA with HART Alarm

APPENDIX C
Return of Materials

Overview ........................................................................................................ 7-1

Grounding ................................................................................................. 7-1

Electrical Noise ........................................................................................ 7-1

Electrostatic Discharge........................................................................... 7-1

Total Power Loss .................................................................................... 7-2

Diagnostic Alarms ......................................................................................... 7-2

Fault Isolation ................................................................................................ 7-3

Alarm Relay Events ....................................................................................7-11

Sensor Housing ............................................................................................. 8-2

Electronics Housing ...................................................................................... 8-6

O2 Cell and Heater Strut Assembly ........................................................... 8-9

Safety Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-2

Safety Data Sheet for Ceramic Fiber Products . . . . . . . . . . . . . . . . . A-24

High Pressure Gas Cylinders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-30

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-1

Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-1

Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-2

Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-2

Returning Material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .C-1

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July 2018

OCX 8800

TOC-2

00809-0300-

ESSENTIAL
INSTRUCTIONS

Rosemount OCX 8800
Oxygen and Combustibles
Transmitter

Emerson designs, manufactures and tests its products to meet many national
and international standards. Because these instruments are sophisticated
technical products, you MUST properly install, use, and maintain them to
ensure they continue to operate within their normal specifications. The
following instructions MUST be adhered to and integrated into your safety
program when installing, using, and maintaining Emerson’s Rosemount
products. Failure to follow the proper instructions may cause any one of the
following situations to occur: Loss of life; personal injury; property damage;
damage to this instrument; and warranty invalidation.

•

Read all instructions prior to installing, operating, and servicing the
product.

•

If you do not understand any of the instructions, contact your
Emerson representative for clarification.

•

Follow all warnings, cautions, and instructions marked on and
supplied with the product.

•

Inform and educate your personnel in the proper installation,
operation, and maintenance of the product.

•

Install your equipment as specified in the Installation Instructions
of the appropriate Instruction Manual and per applicable local and
national codes. Connect all products to the proper electrical and

pressure sources.

•

To ensure proper performance, use qualified personnel to install,
operate, update, program, and maintain the product.

•

When replacement parts are required, ensure that qualified people use
replacement parts specified by Emerson. Unauthorized parts and
procedures can affect the product's performance, place the safe
operation of your process at risk, and VOID YOUR WARRANTY.
Look-alike substitutions may result in fire, electrical hazards, or
improper operation.

•

Ensure that all equipment doors are closed and protective covers
are in place, except when maintenance is being performed by
qualified persons, to prevent electrical shock and personal injury.

READ THIS PAGE BEFORE PROCEEDING!

The information contained in this document is subject to change without
notice.

If a Model 275/375 Universal HART® Communicator is used with this unit, the software
within the Model 275/375 may require modification. If a software modification is required,
please contact your local Emerson Service Group or National Response Center at 1-800­654-7768.

Reference Manual

July 2018

OCX 8800

00809-0300-4880, Rev AA

PREFACE The purpose of this manual is to provide a comprehensive understanding of

the OCX 8800 components, functions, installation, and maintenance.
We recommend that you thoroughly familiarize yourself with the Introduction

and Installation sections before installing your transmitter.
The introduction presents the basic principles of the transmitter along with its

performance characteristics and components. The remaining sections contain
detailed procedures and information necessary to install and service the
transmitter.

Before contacting Emerson concerning any questions, first consult this
manual. It describes most situations encountered in your equipment's
operation and details necessary action.

DEFINITIONS The following definitions apply to WARNINGS, CAUTIONS, and NOTES

found throughout this publication.

Highlights an operation or maintenance procedure, practice, condition, statement, etc. If not
strictly observed, could result in injury, death, or long-term health hazards of personnel.

SYMBOLS

Highlights an operation or maintenance procedure, practice, condition, statement, etc. If not
strictly observed, could result in damage to or destruction of equipment, or loss of
effectiveness.

NOTE

Highlights an essential operating procedure, condition, or statement.

: EARTH (GROUND) TERMINAL

: PROTECTIVE CONDUCTOR TERMINAL
: RISK OF ELECTRICAL SHOCK
: WARNING: REFER TO INSTRUCTION BULLETIN

NOTE TO USERS

The number in the lower right corner of each illustration in this publication is a
manual illustration number. It is not a part number, and is not related to the
illustration in any technical manner.

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ii

00809-0300-

Section 1 Description and Specifications

Component Checklist . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 1-1

System Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 1-1

Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 1-12

COMPONENT
CHECKLIST

SYSTEM OVERVIEW Scope

A typical OCX 8800 Oxygen/Combustibles Transmitter package should
contain the items shown in Figure 1-1.

Use the product matrix in Table 1-1 at the end of this section to verify your
order number. The first part of the matrix defines the model. The last part
defines the various options and features of the OCX 8800. Check the model
number against the transmitter features and options, making sure options
specified by this number are on or included with the unit. Use this complete
model number for any correspondence with Emerson. A list of accessories
for use with the OCX 8800 is provided in Table 1-2.

This Instruction Manual supplies details needed to install, startup, operate,
and maintain the OCX 8800. Signal conditioning electronics outputs separate
4-20 mA signals representing oxygen (O
This information, plus additional details, can be accessed with the HART
Model 275/375 handheld communicator or Rosemount AMS software.

) and combustibles (COe) values.

2

System Description

The OCX 8800 is designed to measure oxygen and combustible
concentrations in flue gas temperatures up to 2600°F (1427°C). Electrical
connections, power and communications are made through two 3/4 NPT ports
in the flameproof electronics enclosure using fittings and cables provided by
the customer. Cable installation must meet NEC, IEC and/or other applicable
national or local codes for Class I, Zone 1, Group IIB +H2 T3/T6 permanently
mounted equipment. The transmitter is close coupled to the process and
requires minimal sample conditioning requirements.

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July 2018

OCX 8800

1-2

1

4

6

MAN 4275A00

o

FISHER

-ROSEMOUNT

TM

2 3

37390076

Figure 1-1. Typical System Package

English

October 1994

HART Communicator

00809-0300-

5

1.

Instruction Manual

2.

Field Communicator Package (optional)

3.

Adapter Plate with Mounting Hardware and Gasket

4.

Reference Air and Calibration Set

5.

Blowback Hardware (optional)

6.

OCX 8800 with Remote Electronics

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00809-0300-4880, Rev AA

The equipment measures oxygen percentage by reading the voltage
developed across a heated electrochemical cell, which consists of a small
yttria-stabilized, zirconia disc. Both sides of the disc are coated with porous
metal electrodes. When operated at the proper temperature, the millivolt
output of the cell is given by the following Nernst equation:

EMF = KT log10 (P

Where:

1.

P2 is the partial pressure of the oxygen in the measured gas on one side
of the cell.

2.

P1 is the partial pressure of the oxygen in the reference air on the
opposite side of the cell.

3.

T is the absolute temperature.

4.

C is the cell constant.

5.

K is an arithmetic constant.

NOTE

For best results, use clean, dry instrument air (20.95% oxygen) as the
reference air.

When the cell is at operating temperature and there are unequal oxygen
concentrations across the cell, oxygen ions will travel from the high oxygen
partial pressure side to the low oxygen partial pressure side of the cell. The
resulting logarithmic output vo ltag e is approximately 50 mV per decade. The
output is proportional to the inverse logarithm of the oxygen concentration.
Therefore, the output signal increases as the oxygen concentration of the
sample gas decreases. This characteristic enables the OCX 8800 to provide
exceptional sensitivity at low oxygen concentrations.

1/P2

) + C

The OCX 8800 measures net oxygen concentration in the presence of all the
products of combustion, including water vapor. Therefore, it may be
considered an analysis on a "wet" basis. In comparison with older methods,
such as the portable apparatus, which provides an analysis on a "dry" gas
basis, the "wet" analysis will, in general, indicate a lower percentage of
oxygen. The difference will be proportional to the water content of the
sampled gas stream.

The OCX 8800 combustibles sensor is a catalytic sensor consisting of two
Resistance Devices (RTD). One RTD is the reference element covered with
an inert coating. The other RTD element is active, coated with a catalyst. As
the sample gases flow by the sensor, the combustible gases oxidize on the
surface of the active element. The oxidation that occurs produces heat and a
temperature rise in the active element. The temperature difference produces
a resistance relationship between the two elements that is directly
proportional to the concentration of combustibles in the sample gases.

1-4

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00809-0300-4880, Rev AA

The catalyst is specifically designed to detect carbon monoxide (CO), but the
sensor responds to other combustible gases. The sensor is calibrated using
CO, thus the output should be expressed in terms of CO. However, since the
sensor detects other combustible gases, the output cannot just be labeled
CO. The response of the sensor to other combustible gases gives an output
that is equivalent to the sensor detecting CO. The term COe is used in this
manual to describe the sensor output. This term indicates that the sensor is
calibrated in terms of CO, and that the sensor output is equivalent to CO but
not specific to CO.

Dilution air is provided to the COe sensor to ensure there is adequate oxygen
to fully oxidize any combustible gases regardless of the concentration of
oxygen in the process.

System Configuration

Transmitters are available in four lengths, giving the user the flexibility to use
a penetration appropriate to the size of the stack or duct. The length options
are 18 in. (457 mm), 3 ft (0.91 m), 6 ft (1.83 m), or 9 ft (2.7 m). Probes are
available in three material options, 316L stainless steel, inconel 600, and
ceramic to accommodate higher temperatures.

The electronics are contained in a separate housing from the sensors. The
electronics housing may be mounted up to 150 feet away from the sensor
housing.

The electronics control both sensor temperatures and provide individual 4-20
mA isolated outputs that are proportional to the measured oxygen and
combustibles concentrations. The power supply can accept voltages of 100 to
240 VAC and 50 to 60 Hz. The electronics accepts millivolt signals generated
by the sensors and produces the outputs to be used by remotely connected
devices. The outputs are isolated 4-20 mA linearized currents. Refer to
Section 3, Configuration and Startup for specific instructions upon initial
power up.

System Features

1.

The O2 cell output voltage and sensitivity increase as the oxygen
concentration decreases.

2.

HART communication is standard. To use the HART capability, you
must have either:

a.

Model 275/375 Field Communicator.

b.

AMS software for the PC.

3.

Oxygen cell and heater /t he rmocouple assembly are field replaceable.

4.

Electronics are automatically configured for line voltages from 100 to
240 VAC.

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00809-0300-4880, Rev AA

5.

An operator can calibrate and diagnostically troubleshoot the OCX 8800
using the HART Interface. Each of the OCX 8800's 4-20 mA output lines
transmit an analog signal proportional to oxygen or combustible levels
detected. The HART output is superimposed on the oxygen 4-20 mA
output line only. This information can be accessed through the following:

•

Model 275/375 Handheld Communicator - The handheld
communicator requires Device Description (DD) software specific
to the OCX 8800. The DD software will be supplied with many
Model 275/375 units, but can also be programmed into existing
units at most Emerson service offices. Refer to Section 4, Using
HART Communications, for additional information.

•

Personal Computer (PC) - The use of a personal computer
requires AMS software available from Emerson.

•

Selected Distributed Control Systems - The use of distributed
control systems requires input/output (I/O) hardware and AMS
software which permit HART communications.

6.

Optional Blowback System. The blowback system periodically blows
instrument air back throug h the sample line filter a nd o ut the s ample
tube. This clears out particulate and keeps the sample line filter from
clogging.

System Operation

Figure 1-2 shows the relationship between the components of the OCX 8800.
The sensors and the electronics are contained in separate housings. The
sensor housing and probe mounts to a duct or process wall so that the probe
protrudes into the flue gas stream. An air powered eductor continuously pulls
samples of the process flue gas through the probe to a chamber in front of the
sensor housing where the sample passes the O
the COe sensor. Dilution air is provided to the COe sensor and reference air
to the O
the COe sensor, it is drawn through the eductor where it mixes with the
eductor air and exits through exhaust back into the system. The electronics
housing contains the CPU and HART boards which convert the sensor inputs
into 4-20 mA analog output signals. The CPU can also initiate and perform
calibrations. Three test gasses and instrument air can be turned on and off by
solenoids. Test gas flow to the sensors is regulated by a flow meter between
the electronics and sensor housings. Instrument air is separated into eductor
air, reference air, and dilution air. The instrument air solenoid does not allow
air flow until the heaters are up to temperature. This minimizes the amount of
sampled process flue gas being pulled into cold sensors causing
condensation.

sensor. After the gas sample flows past the O2 sensor and through

2

sensor and continues on to

2

1-6

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OCX 8800

Test Gas

37390001

Figure 1-2. System Operation Diagram

Probe

Combustibles

Sensor

Sample

Gas

Exhaust

SENSOR

HOUSING

COe

Sensor

O

2

Eductor

Reference Air

Flow Meter

7 scfh

ELECTRONICS

Instrument Air

Eductor Air

HOUSING

CPU

HART
Board

Power

Supply

Optional
Test Gas
Solenoids

Solenoid

00809-0300-4880, Rev AA

Low O

2

High O

2

Test Gas

CO

Test Gas

Instrument

Air

Dilution Air

Flow Meter

50 cc/min.

(0.1 scfh)

Handling the OCX 8800

It is important that printed circuit boards and integrated circuits are handled only when
adequate antistatic precautions have been taken to prevent possible equipment damage.

The OCX 8800 is designed for industrial application. Treat each component of the system
with care to avoid physical damage. The probe may contain components made from
ceramics, which are susceptible to shock when mishandled.

System Considerations

Prior to installing your OCX 8800, make sure you have all the components
necessary to mak e the system installation. Ens ure al l t he c omponents are
properly integrated to make the system functional.

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00809-0300-4880, Rev AA

After verifying that you have all the components, select mounting locations
and determine how each component will be placed in terms of available line
voltage, ambient temperatures, environmental considerations, convenience,
and serviceability. Figure 1-3 shows a typical system wiring. Simplified
installations for the OCX 8800 are shown in Figure 1-4. Figure 1-6 shows the
dimensions for the optional sample tube support.

A source of instrument air is required at the OCX 8800 for reference air,
dilution air, and eductor air. Since the OCX 8800 is equipped with an in-place
calibration feature, provision should be made for connecting test gas tanks to
the OCX 8800 when it is to be calibrated.

NOTE

The electronics module is designed to meet NEMA 4 (IP66) and the electronic
components are rated to temperatures up to 185°F (8 5°C).

Retain packaging in which the unit arrived from the factory in case any
components are to be shipped to another site. This packaging has been
designed to protect the product.

Figure 1-3. OCX 8800 HART
Connections and AMS Application

1-8

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OCX 8800

37390064

Figure 1-4. Typical System
Installation

Power Ca ble

[up to 150 ft (46 m)]

Signal Cable

[up to 150 ft (46 m)]

Figure 1-5. OCX 8800 HART

Heater

Gases

Stack

Dilution

Air

Flow

Meter

00809-0300-4880, Rev AA

Duct

Flow Meter

OCX 8800 with

REMOTE

ELECTRONICS

Test Gas

Pressure

Regulator

High O2 Test Gas
Low O
CO Test Gas

4-20 mA Outputs
(2 Twisted Pairs)

Line Voltage

Instrument Air

Supply

(Reference Gas)

Test Gas

2

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Connections and AMS Application

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Figure 1-6. Sample Tube Support

00809-0300-4880, Rev AA

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1-11

37390064

00809-0300-4880, Rev AA

Figure 1-7. Typical System
Installation

Power Ca ble

[up to 150 ft (46 m)]

[up to 150 ft (46 m)]

Heater

Signal Cable

Gases

Stack

Dilution

Air

Flow

Meter

Duct

Flow Meter

OCX 8800 with

REMOTE

ELECTRONICS

Test Gas

Pressure

Regulator

High O2 Test Gas
Low O
CO Test Gas

4-20 mA Outputs
(2 Twisted Pairs)

Line Voltage

Instrument Air

Supply

(Reference Gas)

Test Gas

2

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1-12

Blowback Air (optional) Clean, dry, instrument-quality air (20.95% O2), regulated to ≥ 60 psi

SPECIFICATIONS General Purpose OCX

Specifications

Net O2 Range 0-1% to 0-40% O2, fully field selectable
Combustibles 0-1000 ppm to 0-5%, fully field selectable
Accuracy

Oxygen ± 0.75% of reading or 0.05% O
Combustibles ± 2% range

System Response to
Test G as

Oxygen 10 sec T90
Combustibles 25 sec T90

Temperature Limits

Process 32°to 2600°F (0° to 1427°C)
Sensors Housing -40°to 212°F (-40°to 100°C), ambient
Electronics Housing -40°to 149°F (-40°to 65°C), ambient

Nominal and Approximate
Shipping Weights

18 in. (457 mm)
probe package

3 ft (0.91 m) probe
package

6 ft (1.83 m) probe
package

9 ft (2.74 m) probe
package

Mounting and Mounting
Positions

Sensors Housing Flange

Electronics Housing Wall/Pipe

Materials

Probes 316L stainless steel - 1300°F (704°C)

Enclosures Low-copper aluminum
Calibration Semi-aut omatic or automatic
Calibration Gas Mixtures

Recommended

(Ref. test gas bottles

kit #1A99119G04)
Calibration Gas Flow 7 scfh (3.3 l/m)
Reference Air 2 scfh (1 l/m), clean, dry instrument-quality air (20.95% O

Eductor Air 5 scfh (2.5 l/m), clean, dry, instrument-qualit y air 20.95% O

Dilution Air 0.1 scfh (0. 5 l/m), clean, dry, instrument-quality air (20.95% O

00809-0300-4880, Rev AA

(whichever is greater)

-40°to 185°F (-40°to 85°C), internal - operating temperature of
electronics inside instrument housing, as measured by a HART
communicator or AMS software

2

54 lbs (20 kg)

55 lbs (20.5 kg)

57 lbs (21 kg)

59 lbs (22 kg)

Inconel 600 - 1832°F (1000°C)
Ceramic - 2600°F (1427°C)

0.4

% O2, Balance N2

8% O

, Balance N2

2

1000 ppm CO, Balance Air

regulated to 35 psi (241 kPa)

regulated to 35 psi (241 kPa)

regulated to 35 psi (241 kPa)

(413 kPa) or greater and ambient temperature of ≥ 0 °F (-18 °C)

Table continued on next page

),

2

),

2

)

2

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C

U

00809-0300-4880, Rev AA

Specifications

Sensors Housing NEMA 4, IP66 with fitting and pipe on reference exhaust port to clean, dry

atmosphere, two 3/4-14 NPT conduit ports (when reference vents are
routed to a dry area).

Electronics Housing NEMA 4, IP66 with fitting and pipe on reference exhaust port to clean, dry

atmosphere, two 3/4-14 NPT conduit ports (when reference vents are
routed to a dry area).

Electrical Noise EN 61326-1, Class A

Line Voltage Universal 100 to 240 VAC ±

jumpers required, 3/4-14 NPT conduit port

Pollution Degree 2

Over Voltage Category II

Relative Humidity 5 to 95% (non-condensing)

Isolated Output

Oxygen 4-20 mAdc, 950 ohm maximum, with HART capability

Combustibles 4-20 mAdc, 950 ohm maximum

Alarm Alarm output relay - dry contact, form C, 30mA, 30VDC capacity
Power Consumption 750 W maximum
Mounting and Mounting

Positions

Sensor Housing Flange

Electronics Housing

NOTE
All static performance characteristics are with operating variables constant. Specifications subject to change
without notice.

Wall/Pipe

Certifications

S

10%, 50 to 60 Hz, no switches or

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OCX88A

O2/Combustibles Transmitter

Code

Probe Length and Material

00

No Probe or Exhaust Tube

11

18 in. (457 mm) 316 SST

up to 1300°F (704°C)

(3)

21

18 in. (457 mm) Inconel 600

up to 1832°F (1000°C)

31

18 in. (457 mm) Ceramic

up to 2600°F (1427°C)

12

3 ft (0.91 m ) 316 SST

up to 1300°F (704°C)

22

3 ft (0.91 m) Inconel 600

up to 1832°F (1000°C)

(3)

32

3 ft (0.91 m) Ceramic

up to 2600°F (1427°C)

13

6 ft (1.83 m ) 316 SST

up to 1300°F (704°C)

23

6 ft (1.83 m) Inconel 600

up to 1832°F (1000°C)

(3)

14

9 ft (2.7 m) 316 SST

up to 1300°F (704°C)

24

9 ft (2.7 m) Inconel 600

up to 1832°F (1000°C)

(3)

Code

Probe Mounting Assembly

10

(ANSI 2 in. 150 lb) 6" dia. flange, 4.75" BC with 4 x 0.75" dia. holes

20

(DIN) 185 mm dia. flange, 145 mm BC with 4 x 18 mm dia. holes

Code

Mounting Hardware - Stac k Side

0 No Adapter Plate (“0” must be chosen under “Mounting Adapter - Probe Side” below)

1 New Installation - Square weld plate with studs

2 Model 218/240 Mounting Plate (with Model 218/240 Shiel d Removed)

3 Existing Model 218/240 Support Shield

4 Special Mounting

(1)

5 Model 132 Adapter Plate

Code

Mounting Hardware - Probe Side

0 No Adapter Plate

1 Probe Only (ANSI)

2 Probe Only (DIN)

Code

Electronics Housing - Communications

H1

HART Communications

H2

HART Communicatio ns with Local Operator Interface

H3

HART Communications with Calibration Solenoids

H4

HART Communications with Local Operator Interface and C alibrati on Solenoids

Code

Electronics Mounting

01

Integr al to Sensor H ousing

02

Remote Electronic s and no cable

03

Remote Electronics and 20 ft (6 m) cable

04

Remote Electronics and 40 ft (12 m) cable

05

Remote Electronics and 60 ft (18 m) cable

06

Remote Electronics and 80 ft (24 m) cable

07

Remote Electronics and 100 ft (30 m) cable

08

Remote Electronics and 150 ft (46 m) cable

Code

Accessories

00

None

01

Flow meters & Ref. Air Set

02

In-Situ Filte r (Stainless Steel only)

(2) 03

In-Situ Filter (SST), Flow meters & Ref. Air Set

(2)

11

Flow meters, and Ref. Air Set with Blowback

12

In-Situ Filter (SST) with Blowback

(2) 13

In-Situ Filter (SST), Flow meters & Ref. Air Set with Blowback

(2)

OCX88A

11

10 1 1

H3

06

02

Example

Plate with studs

Bolt circle diameter, number, and arrangement of studs, stud thread, stud height above mounting plate.

Plate without studs

Bolt circle diameter, number, and arrangement of holes, thread, depth of stud mounting plate with accessories.

00809-0300-4880, Rev AA

Table 1-1. Product Matrix - General Purpose OCX 8800

NOTES:

(1)

Provide details of the existi ng mo unti ng pl at e as foll o ws:

(2)

For use with stainless steel sample tube only.

(3)

For high temperature applications that require a filter, please order 1A99762H03 separately.

Reference Manual

July 2018

OCX 8800

1-15

PART NUMBER DESCRIPTION

00809-0300-4880, Rev AA

Table 1-2. Accessories

1A99119H01 Oxygen test gas bottle; 0.4% O2, balance N
1A99119H02 Oxygen test gas bottle; 8.0% O2, balance N

1A 99119H07 CO test gas bottle; 1000 ppm CO, balance air
1A99120H02 Regulator for Oxygen (may need 2)
1A99120H03 Regulator for CO test gas
1A99119G06 Wall mount bracket for test gas bottles
1A99119G05 Test gas regulators kit
1A99119G04 Test gas bottles kit

1A99292H01

1A99339H03 Blowback valve, air operated
1A99762H03 Hasteloy In Situ Filter, High Temperature

1A99784H02

6A00171G01 Power line filter kit
6A00288G01 Sample Tube Support, 18 in. (457 mm)
6A00288G02 Sample Tube Support, 3 Ft. (0.91 m)
6A00288G02 Sample Tube Support, 6 Ft. (1.83 m)
6A00288G04 Sample Tube Support, 9 Ft. (2.7 m)
6P00162H02 Flange Insulator

Moore Industries SPA for Low O
Calibration Status, and Unit Fail

375 Field Communicator with 12 Megabyte buffer,
model no. 375HR1EKLU

Alarm, High COe Alarm,

2

2
2

Reference Manual

July 2018

OCX 8800

00809-0300-4880, Rev AA

Section 2 Installation

Mechanical Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-2

Electrical Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-8

Pneumatic Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-14

Initial Startup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-20

Before installing this equipment, read the "Safety instructions for the wiring and installati on
of this apparatus" in Appendix A: Safety Data. Failure to follow the safety instructions could
result in serious injury or death.

The OCX88A can be installed in general purpose areas only. Do not install the OCX88A in
hazardous areas.

Reference Manual

July 2018

OCX 8800

2-2

00809-0300-4880, Rev AA

MECHANICAL
INSTALLATION

Selecting Location

1.

The location of the OCX 8800 in the stack or flue is most important for
maximum accuracy in the oxygen analyzing process. The probe must
be positioned so the gas it measures is representative of the process.
Best results are normally obtained if the transmitter is positioned near
the center of the duct (40-60% insertion). Longer ducts may require
several transmitters since the oxygen and combustibles can vary due to
stratification. A point too near the wall of the duct or the inside radius of
a bend, may not provide a representative sample because of the very
low flow conditions. The sensing point should be selected so the
process gas temperature falls within the range of probe material used.
Figure 2-1 through Figure 2-4 provide mechanical installation
references. The ambient temperature inside the electronics housing
must not exceed 185°F (85°C).

2.

Check the flue or stack for holes and air leakage. The presence of this
condition will substantially affect the accuracy of the oxygen and
combustibles readings. Therefore, either make the necessary repairs or
install the transmitter up stream of any leakage.

3.

Ensure the area is clear of internal and external obstructions that will
interfere with installation and maintenance access to the unit. Allow
adequate clearance for the removal of the OCX 8800.

Do not allow the temperature of the electronics housing to exceed 185°F (85°C) or damage
to the electronics may result.

Whenever a positive stack pressure exists at the installation site, be sure to connect all
pneumatic lines prior to installing the OCX 8800 in the stack or ductwork. Failure to connect
the pneumatic lines can allow the flow of contaminants into the OCX 8800 ports.

Installation

1.

Ensure all components are available to install the OCX 8800.

2.

The OCX 8800 may be installed intact as it is received.

3.

Weld or bolt adapter plate (Figure 2-2) onto the duct.

4.

Use the pipe or wall mounting hardware as shown in Figure 2-3 to
mount the electronics housing. Choose a location not to exceed the
length of the electronics cable ordered.

5.

Ensure the conduits drop vertically from the OCX 8800 and the conduit
is routed below the level of the conduit ports on the housing to form a
drip loop. Drip loops minimize the possibility that moisture will damage
the electronics (Figure 2-4).

6.

Where a positive stack pressure exists at the installation site, connect all
pneumatic lines prior to installing the OCX 8800 in the stack or
ductwork.

Reference Manual

00809
July 2018

OCX 8800

2-3

-0300-4880, Rev AA

NOTE

If process temperatures will exceed 392°F (200°C), use anti-seize compound
on stud threads to ease future removal of the OCX 8800.

7.

Insert sample and exhaust tubes through the opening in the mounting
flange and bolt the unit to the flange.

Uninsulated stacks or ducts may cause ambient temperatures in the electronics housing to
exceed 185°F (85°C) and damage the electronics.

8.

If insulation is removed to access the duct for OCX 8800 mounting,
make sure to replace insulation afterward.

Enclosures

The OCX 8800 enclosures are designed to meet ingress conditions of IP66.
Each enclosure cover is threaded to its base and sealed with an o-ring that
isolates the threads from external contaminants.

Each cover is secured by a clip attached to the base that engages the cover
between the ribs of the cover sidewall. The clip is held in place by an Allen
head cap screw and lockwasher mounted in a recess. Cover removal and
installation requires an Allen wrench to loosen and tighten the screw.

Reference Manual

July 2018

OCX 8800

4-2

Table 2. Installation/Removal

18

(457)

34

(864)

36

(914)

52

(1321)

72

(1829)

88

(2235)

108

(2743)

124

(3150)

0.06 In. Thick Gasket

ANSI

3535B18H02

DIN

3535B45H01

Heater

Po

wer Cab

le

Signal Cable

Signal Cable

Heater

Po

wer Cab

le

37390009

Table

1. Mounting

Flange

ANSI

DIN

5R10244H01

5R10244H02

Flange
Dia.

6.00

7.28

(152)

(185)

Hole

0.75

0.71

Dia.

(19)

(18)

(4) Holes
spaced on

(121)

(145)

B.C. dia

Figure 2-1. Installation, OCX 8800

NOTE

All dimensions are in inches with millimeters in parentheses.
Insulate if exposed to adverse weather or extreme temperature

changes, install a protective housing and/or insulation
around the unit.

See Table 1

See Table 2

SENSOR HOUSING

Probe Dim "A” Dim "B”
18 in.

Flange Dia.

B.C. Dia.

Hole Dia.

equally

Removal Envelope

Dim “B”

00809-0300-4880, Rev AA

4.75

5.71

Insertion Depth

Dim “A”

Optional

In Situ FIilter

8.3

(211)

3 ft
6 ft
9 ft

Allow 9 in.

(229 mm) for

Cover Removal

ELECTRONICS HOUSING

Reference Manual

00809
July 2018

OCX 8800

2-5

-0300-4880, Rev AA

Figure 2-2. Adapter Plate Installat ion

Reference Manual

July 2018

OCX 8800

6-2

37020021

Figure 2-3. Wall or Pipe Mounting
of Electronics Housing

Note: * Indicates items are included

in mounting kit P/N 4851B40G01.

*Pipe

Mounting

Clamp

*Wall or Pipe

Mounting Bracket

and Screws

00809-0300-4880, Rev AA

Electronics

Housing

Wall Mounting Bolts

or Lag Screws

(4 each by customer)

1/4-20 UNC x 2 in. M-F Standoffs.

Recommended for rear piping

clearance when wall mounting.

(4 each by customer)

Reference Manual

00809
July 2018

OCX 8800

2-7

Conduit Drip Loops

Duct Wall

Conduit Drip Loop

Conduit Drip Loop

Duct Wall

37020004

-0300-4880, Rev AA

Figure 2-4. Installation
with Drip Loops

Reference Manual

July 2018

OCX 8800

8-2

00809-0300-4880, Rev AA

ELECTRICAL
INSTALLATION

All wiring must conform to local and national codes. For reference, factory
wired solenoid power connections are shown in Figure 2-5.

Disconnect and lock out power before connecting the unit to the power supply. Failure to
lock out power could result in serious injury or death.

Install all protective equipment covers and safety ground leads after installation. Failure to
install covers and ground leads could result in serious injury or death.

To meet the Safety Requirements of IEC 1010 (EC requirement), and ensure safe operation
of this equipment, connection to the main electrical power supply must be made through a
circuit breaker (min 10 A) in close proximity and marked for this equipment which will
disconnect all current-carrying conductors during a fault situation. This circuit breaker
should also include a mechanically operated isolating switch. If not, then another external
means of disconnecting the supply from the equipment should be located close by. Circuit
breakers or switches must comply with a recognized standard such as IEC 947.

The OCX88A can be installed in general purpose areas only. Do not install the OCX88A in
hazardous areas.

Reference Manual

00809
July 2018

OCX 8800

2-9

-0300-4880, Rev AA

NOTE

To maintain proper earth grounding, ensure a positive connection exists
between the sensor housing, the electronics housing, and earth. The
connecting ground wire must be 14 AWG minimum. Refer to Figure 2-5.

NOTE

Line voltage, signal, and relay wiring must be rated for at least 105ºC (221ºF).

Electrical Connections

Electrical connections, power and communications are made to the electronic
enclosure. The connections are made through two 3/4 NPT ports in the
enclosure using fittings and cables provided by the customer. Cable
installation must meet NEC, IEC and/or other applicable national or local
codes for Class I, Zone 1, IIB +H2 T3/T6 permanently mounted equipment.

Connect Line Voltage

The OCX 8800 operates on 100 to 240 VAC line voltage at 50 to 60 Hz. The
power supply requires no setup. Connect the line (L wire) to the L terminal,
and the neutral (N wire) to the N terminal on the AC power input terminal
block in the electronics housing. Connect the ground (G wire) to the ground
stud in the electronics housing as shown in Figure 2-5.

Connect 4-20 mA Signals

Connect the 4-20 mA current loop to the 4-20 mA signal output terminals in
the electronics housing as shown in Figure 2-5. Use individual shielded
twisted wire pairs. Terminate the shield at the electronics housing.

4-20 mA Signal

O

2

One 4-20 mA signal represents the O

value. Superimposed on the O

2

2

signal is the HART information accessible through a Model 275/375

Handheld Communicator or AMS software. The O

signal is at the AOUT 1

2

terminals.

COe 4-20 mA Signal

Another 4-20 mA signal at the AOUT 2 terminals represents the COe
value. HART information is not available on the COe signal.

Alarm Output Relay

Connect any customer-supplied relay input to the alarm output relay terminal.
Use shielded wire and terminate the shield at the electronics housing. The
alarm output relay terminal is a set of dry, no. 2, form C, contacts with 30 mA,
30 VDC capacity.

Reference Manual

July 2018

OCX 8800

2-10

00809-0300-4880, Rev AA

Remote Electronics Connections to Sens or Housing

Make the following connections between the electronics and sensor housings
with the electronics cable order ed with the pac k age (Fi gur e 2-6). Br a ide d
cable is available in lengths up to 150 ft. (46 m).

NOTE

Interconnect wiring shown is for Rosemount supplied cables. For customer
furnished interconnect wiring or cables, refer to Figure 2-7.

Signal Connections

Connect the electronics housing terminals to the corresponding terminals
in the sensor housing. The twisted wire pairs are numbered on the inner
plastic wrapper. Keep twisted pairs together and match the numbers and
wire colors shown in Figure 2-6.

Heater Power Connections

Use the blue, white, orange black, red, and yellow stranded wires in the
heater power cable to connect power to the three heaters in the sensor
housing. Match the wire colors to the corresponding heater power terminal
blocks in the sensor and electronics housings as shown in Figure 2-6.

Reference Manual

00809
July 2018

OCX 8800

2-11

{

AOUT1 -

37390013

-0300-4880, Rev AA

Figure 2-5. Line Voltage, Earth,
and 4-20 mA Connections

#1

NC

COM

NO

Alarm Output Relay

Terminal Block

COe Signal

O

Signal

2

TOP VIEW

(1/2 SIZE)

Ground Stud

Typical for Electronics and

4-20

AOUT2+

AOUT2 -

{

AOUT1+

Terminal Block

EMI Filter

Earth Ground

Sensor Housing

mA Signal Output

#1

Customer

Wiring

G

N L1

G

Terminal

Block

Ground

Stud

Signal Port

3/4 NPT

Power Port

3/4 NPT

G

External Tooth

Lockwasher

Reference Manual

July 2018

OCX 8800

2-12

Signal Cable

Heater

Po

wer Cab

le

BLU BLK -

+

O2

O2

GRN BLK +

BLK - T/C CO

RED +

BLK - T/C

SB
WHT + BLK EXC- BLK - CJC ORG + BLK

2

HTR

1

ORG

WHT

- CO

YEL

REF

RED BLK GRN RED - CO

SHIELD

BRN WHT

ACT

+

2 HTR BLU YEL

1

SB

EXC

+
GRN

37390014

Figure 2-6. Electrical Connections Between Remote Electronics and Sensor Housing

YEL
RED
BLK

ORG

WHT

BLU

Heater Power

Connector (J3)

#1

2HTR CO
1HTR CO
2HTR O

1HTR O
2HTR

1HTR SB

2

2 To

SB

ground

screw

#1

RED
BLK

WHT
BLK
GRN

BLK
BLU

BLK

O

Sensor and

2

Thermocouple
Connector (J5)

#1

T/C CO+
T/C CO-

T/C SB+
T/C SB­T/C O2+
T/C O2-

O2 CELL+
O2 CELL-

SHLD

To ground

screw

#1 #1

YEL

BRN

BLK

RED
WHT
ORG

BLK

BLK

#1

EXC+
CO ACT+
CO ACT-

CO REF+
CO REF-

CJC+
CJC­EXC-

COe Sensor

and

Cold Junction

Connector

(J4)

00809-0300-4880, Rev AA

ELECTRONICS HOUSING

SENSOR HOUSING

+

T/C

O2

HTR

1

CO

2

To ground screw

Reference Manual

00809
July 2018

OCX 8800

2-13

37390061

-0300-4880, Rev AA

Figure 2-7. Customer-Furnished
Interconnect Wiring or Cables

NOTE: For RFI/CE compliance, the connector

must provide 360 degrees of electrical
contact to the cable shield.

ELECTRONICS END

7.25

±0.10

Strip Wire

Ends 3/16”

Typical

0.5

Typ.

4.0 ±0.10

Strip Wire

Ends 3/16”

Typical

Green,

16 AWG

Stud Size

#10

Stud Size

#10

7.25 ±0.10

9.25 ±0.10

ELECTRONICS END

4.5 ±0.10

0.5
Typ.

SIGNAL WIRING OR CABLE

Heat Shrink

Tubing

2” Long

1/2” Size

7.0” Long Teflon Tubing,

0.042” ID (Cut off drain
wire at probe end of
shield).

See Note

2.0 ±0.25
Typical

Overall Cable Length

By Customer

150’ Maximum

HEATER WIRING OR CABLE

Heat Shrink Tubing

2” Long, 1/2” Size

2.0 ±0.25 Typical

4.25” Long Teflon Tubing,

0.042” ID. (Cut off drain wire
at probe end of shield).

3/4 NPT Hub Size,

Liquid-tight
Strain Relief
Connector

3/4 NPT Hub Size,

Liquid-tight
Strain Relief
Connectors

See Note

8 twisted pairs 24 AWG,
stranded, insulated,
tinned copper
conductors, 200
volts, with overall braid
of 34 AWG tinned
copper, 90% coverage
and 24 AWG tinned
copper, uninsulated
drain wire.

8 Conductors, 16 AWG, Stranded,
200
Braided shield - tinned copper, 90%
coverage with 18 AWG 24 tinned copper,
uninsulated, drain wire.

Heat Shrink

Tubing

2” Long

1/2” Size

o

C, 300

(typical on both ends of wiring)

Heat Shrink Tubing

2” Long, 1/2” Size

O

C, 600 volts.

3.875
±0.10

4.625
±0.10

DETAIL

PROBE END

12.5 ±0.10

10.375 ±0.10

8.625 ±0.10

6.875 ±0.10

A

5.375
±0.10

6.125
±0.10

# 1

# 2

Heat Shrink Tubing
1” Long, 3/16” Size

A

PROBE END

5.5 ±0.10

Ferrule, Uninsulated

Green, 16 AWG

Ferrule,
Uninsulated

Stud Size #6

Reference Manual

July 2018

OCX 8800

2-14

00809-0300-4880, Rev AA

PNEUMATIC
INSTALLATION

Pneumatic system connections depend on whether reference air set,
calibration solenoids, and/or blowback equipment options are equipped on
your transmitter. Refer to the following paragraphs and select the option that
applies to your transmitter configuration.

Reference Air Set Option (only)

When no options or only the reference air set option is equipped, use the
following procedure to install the pneumatic system components.

1.

Refer to Figure 2-8. Connect the reference air set (regulator/filter and
pressure gage) to the instrument air inlet on the electronics housing and
to the inlet side of the dilution air flow meter.

2.

Connect the dilution air flow meter output to the dilution air inlet fitting on
the sensor housing.

3.

Install an air line between the instrument air outlet fitting on the
electronics housing and the tee fitting on the sensor housing.

.

Do not use 100% nitrogen as an O2 low gas. It is suggested that O2 low gas be between

0.4% and 2.0% O
parts per million. Failure to use proper gases will result in erroneous readings.

4.

One CO gas and two O2 gases are used to calibrate the OCX 8800:

. Do not use gases with hydrocarbon concentrations of more than 40

2

CO - 1000 ppm or up to 4%, Balance air

low gas - 0.4% , Balance N

O

2

O2 high gas - 8%, Balance N

2

2

Connect the output of the test gas sources to the inlet port of the CAL
GAS flow meter. Install an air line between the flow meter outlet port and
the CAL GAS inlet fitting on the sensor housing.

Reference Manual

00809
July 2018

OCX 8800

2-15

(

CO

HI O

LO O

37390011

-0300-4880, Rev AA

Figure 2-8. Pneumatic
Installation, OCX with Reference
Air Set (without Autocalibration)

Eductor

Air In

Sensor

Housing

Reference Air In

Dilution Air In

Electronics

Housing

CAL Gas In

Dilution Air

Flow Meter

0.1 scfh

Instrument

Air Out

CAL Gas

Flow Meter

7 scfh, 20-30 psig

Recommended

2

Air Supply

Pressure Reguator/Filter

35 psig - General Purpose

45 psig - Hazardous Area

2-

Stage

Regulators

2

Instrument

Reference Manual

July 2018

OCX 8800

2-16

Sensor

Housing

(

CAL Gas

7 scfh,

psig

Recommended

CAL Gas In

Reference

Air In

Eductor

Air In

Dilution

Air In

Dilution Air

0.1 scfh

Electronics

Housing

Ins

Pressure Regulator/Filter
35 psig - General Purpose
45 psig - Hazardous Area

2-Stage

Regulators

Instrument

Air

Out

CAL Gas

Out

LO O

HI O

2

CO

37390012

Figure 2-9. Pneumatic
Installation, OCX with Reference
Air Set and Solenoids (with
Autocalibration)

Flow Meter

20-30

2

Reference Air Set and Solenoids Option

00809-0300-4880, Rev AA

Flow Meter

trument

Air

Supply

When the reference air set and test gas solenoids are included with your
OCX 8800, use the following procedure to install the pneumatic system
components.

1.

Install the reference air set according to the instructions in Reference Air
Set Option, steps 1 through 3.

2.

Refer to Figure 2-9. Connect the O2 low gas source to the CAL GAS LO

inlet fitting on the electronics housing. Install a shutoff valve and

O

2

pressure regulator with gage in the O

3.

Connect the O2 high gas source to the CAL GAS HI O2 inlet fitting.
Install a shutoff valve and pressure regulator with gage in the O

low supply line, as shown.

2

2

high

supply line.

Reference Manual

00809
July 2018

OCX 8800

2-17

-0300-4880, Rev AA

4.

Connect the CO high gas to the CAL GAS HI COe inlet fitting. Install a
shutoff valve and pressure regulator with gage in the CO high supply
line.

5.

Connect the CAL GAS outlet fitting of the electronics housing to the inlet
port of the CAL GAS flow meter. Install an air line between the flow
meter outlet port and the CAL GAS inlet fitting on the sensor housing.

Reference Air Set, Solenoids, and Blowback Option

The blowback system blows instrument air back through the blowback filter
and out the sample tube of the transmitter. This removes built up dirt and
particulate from the filter and sample line. The blowback option is normally
used in systems that have a dirty process stream.

Installing an OCX 8800 with the blowback option requires the addition of air
operated blowback valve, regulator and gage, and check valve.

Figure 2-10 shows the piping arrangement for the OCX 8800 with the
blowback and autocalibration options. Figure 2-11 shows the piping
arrangement for the OCX 8800 with the blowback option, but without
autocalibration (without test gas solenoids).

When the reference air set, calibration gas solenoids, and blowback options
are included with your transmitter, use the following procedure to install the
pneumatic system components.

1.

Connect the calibration gas sources according to the instructions in the
previous paragraph “Reference Air Set and Solenoids Option”, steps 2
through 5.

2.

Connect a clean, dry, instrument-quality supply of air (20.95% O2) to the
35/45 psig and 55 psig pressure regulators. The inlet to the 35/45 psig
regulator accepts a 1/8" NPT fitting. The inlet to the 55 psig regulator
accepts a 1/4" NPT fitting.

3.

See the upper leg of the instrument air supply. Connect the output of the
35/45 psi regulator/f ilter to one por t of the normally-clos ed air-operated
solenoid valve, and to the inlet side of the dilution air flow meter.

4.

Connect the dilution air flow meter output to the DILUTION AIR inlet
fitting on the sensor housing.

5.

Install an instrument air line between the open port of the normally-open
air-operated solenoid valve and the tee fitting on the sensor housing.

6.

Connect the output of the 55 psi regulator/filter to one port of the
normally-open air-operated solenoid valve, and to the instrument air
inlet on the back of the electronics housing.

7.

Install an air line between the open port of the normally-closed
air-operated solenoid valve and the check valve inlet fitting on the
sensor housing.

Reference Manual

July 2018

OCX 8800

2-18

Figure 2-10. Piping Arrangem ent,
Blowback with Autocalibration

00809-0300-4880, Rev AA

Reference Manual

00809
July 2018

OCX 8800

2-19

-0300-4880, Rev AA

Figure 2-11. Piping Arrangem ent ,
Blowback without Autocalibration

Reference Manual

July 2018

OCX 8800

2-20

00809-0300-4880, Rev AA

8.

Install an air line between the instrument air outlet fitting on the
electronics housing and the control air inlet fitting on the air-operated
solenoid valve.

9.

There are three settings that need to be specified to set up the blowback
option. These are the blowback interval, duration, and purge time.

Interval - Length of time between blowback events.
(60 minutes recommended.)

Duration - Length of time blowback air is activated.
(5 seconds recommended.)

Purge - Length of time after blowback is complete before
oxygen/combustibles readings are considered valid.
(Set as required by the application.)

These settings are available through HART from the DEVICE SET U P >

DETAILED SETUP > OUTPUT CONDITIONS > BLOWBACK menu.

INITIAL STARTUP Observe the following Caution and Note. Refer to Section 3: Configuration

and Startup, for OCX 8800 startup information.

Upon completing installation, make sure that the OCX 8800 is turned on and operating prior
to firing up the combustion process. Damage can result from having a cold OCX 8800
exposed to the process gases.

If ducts will be washed down during outages, make sure to power down the OCX 8800 units
and remove them from the wash area.

NOTE

During outages, and whenever possible, leave OCX 8800 units running to
prevent condensation and premature aging from thermal cycling.

Reference Manual

00809
July 2018

OCX 8800

-0300-4880, Rev AA

Section 3 Configuration and Startup

Verify Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 3-1

Initial Power Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 3-3

Set Test Gas Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 3-4

OCX 8800 Reset Procedure . . . . . . . . . . . . . . . . . . . . . . . . page 3-4

Install all protective equipment covers and safety ground leads after installation. Failure to
install covers and ground leads could result in serious injury or death.

VERIFY INSTALLATION Ensure the OCX 8800 is installed correctly. Verify mechanical installation and

all electrical and pneumatic connections. Refer to Section 2, Installation.

Make sure that the OCX 8800 is turned on and operating prior to firing up the combustion
process. Damage can result from having a cold OCX 8800 exposed to the process gases.

NOTE

During outages, and whenever possible, leave all OCX 8800 units running to
prevent condensation and premature aging from thermal cycling.

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OCX 8800

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00809-0300-

Verify Configuration

There are three switches on the microprocessor board which are user
configurable for the OCX 8800 (Figure 3-1). SW1 determines if the O
mA signal is internally or externally powered. SW2 determines if the COe 4-20
mA signal is internally or externally powered. SW3 sets the rail limits for the

and COe 4-20 mA signals and configures the sample line heater control

O

2

circuit. All switches are accessible through holes in the electronics box.

4-20

2

Remove power from the OCX 8800 before changing defaults. If defaults are changed under
power, damage to the electronics may occur.

Verify that the following switch settings are correct for your OCX 8800
installation:

SW1 The two settings are internally or externally powering the O
mA signal. The factory setting is for the O
powered.

4-20 mA signal to be internally

2

4-20

2

SW2 The two settings are internally or externally powering the COe 4-20
mA signal. The factory setting is for the COe 4-20 mA signal to be
internally powered.

SW3 The factory sets this switch as follows:

•

Position 1 determines the O2 4-20 mA signal rail limit. The settings are
high, 21.1 mA, or low, 3.5 mA. The factory setting is low, 3.5 mA.

•

Position 2 determines the COe 4-20 mA signal rail limit. The settings
are high, 21.1 mA, or low, 3.5 mA. The factory setting is high, 21.1 mA.

•

Positions 3 and 4 must be set as shown for proper software control of
the device heaters.

Reference Manual

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OCX 8800

SW3

O

COe

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Figure 3-1. OCX 8800 Defaults

Open

Closed

COe 4-20 mA

is Internally

Switch

Default Postions

Shown

Internal:

Powered

SW2

2

21.1 mA

3.5 mA
1 2 3

1 2 3 4

External:
COe 4-20 mA
Requires an External
Power Supply
(Default)

4

Open

Closed

O

21.1 mA/3.5 mA: O

2

Open

Closed

COe 21.1 mA/3.5 mA: COe 4-20 mA Signal

Open

Closed

Internal:
4-20 mA

O

2

is Internally

Powered

4-20 mA Signal

2

Rail Limits:
High - 21.1 mA
Low - 3.5 mA

Rail Limits:
High- 21.1 mA
Low - 3.5 mA

SW1

External:
O

2

Requires an External
Power Supply
(Default)

4-20 mA

INITIAL POWER UP Allow adequate time (approximately 60 minutes) for the heaters to begin

operation and for the OCX 8800 to reach normal operating temperature on
power up. Normal operating temperature for the O

cell is 736°C. Normal

2

operating temperature for the combustibles cell is 300°C. The normal sample
line temperature is 170°C. During this time the edu ctor air solenoid will remain
closed so no sample is pulled through the analyzer. When the OCX reaches
operating temperature the solenoid will energize, eductor air will begin to flow,
and the unit will begin normal operation.

3-3

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SET TEST GAS VALUES Use HART/AMS to set test gas values for calibration. Refer to Section 4,

Using HART Communications for more information.

Setting Test Gas Values with HART

1.

Use the 275/375 Field Communicator or AMS software to access the
HART menu.

2.

From the DETAILED SETUP menu, select O2 CALIB PARAMS.

3.

From O2 CALIB PARAMS, select O2 High Gas. Enter the percent O
used for the high O2 test gas.

4.

From O2 CALIB PARAMS, select Low TG. Enter the percent O2 used
for the low O

5.

From the DETAILED SETUP menu, select COe CALIB PARAMS.

6.

From COe CALIB PARAMS, select COe Test Gas. Enter the CO
concentration (ppm) used for COe test gas.

test gas.

2

2

OCX 8800 RESET
PROCEDURE

Whenever you correct an equipment alarm or fault condition, the OCX 8800
will either revert to normal operation or continue to indicate an alarm status
condition. If the equipment does not revert to normal operation when a fault
condition is cleared, or if instructed to do so in Section 7, Troubleshooting,
use the following procedure to reset the OCX 8800.

OCX Reset with HART

Remove the OCX 8800 from the process loop and recycle power.

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OCX 8800

-0300-4880, Rev AA

Section 4 Using HART Communications

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 4-1

Field Communicator Signal C onnection s . . . . . . . . . . . . pag e 4-1

Field Communicator PC Connectio ns . . . . . . . . . . . . . . . page 4-4

HART Menu Tree . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 4-5

D/A Trim Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 4-9

OVERVIEW The Field Communicator is a handheld communications interface device. It

provides a common communications link to all microprocessor-based
instruments that are HART compatible.

To interface with the OCX 8800, the Field Communicator requires a
termination point along the O
resistance of 250 ohms between the communicator and the power supply.
The Field Communicator accomplishes its task using a Frequency Shift
Keying (FSK) technique. With the use of FSK, high-frequency digital
communication signals are s uper imposed on the 4-20 mA oxygen output
signal. The communicator does not disturb the 4-20 mA signal since no net
energy is added to the loop. HART information is not available on the COe
output signal.

4-20 mA current loop and a minimum load

2

FIELD COMMUNICATOR
SIGNAL CONNECTIONS

The Field Communicator may be interfaced with a personal computer (PC),
providing special software has been installed. To connect the Field
Communicator may to a PC, an interface adapter is required. Refer to the
proper Field Communicator documentation in regard to the PC interface
option.

The Field Communicator can connect to the OCX 8800 oxygen analog output
signal line at any wiring termination in the O

4-20 mA current loop. There are

2

two methods of connecting the Field Communicator to the signal line. For
applications in which the signal line has a load resistance of 250 ohms or
more, refer to method 1. For applications in which the signal line loa d
resistance is less than 250 ohms, refer to method 2.

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July 2018

OCX 8800

4-2

Figure 4-1. Signal Line Connections,

≥ 250 Ohms Load Resistance

00809-0300-

Method 1, for Load Resistance ≥ 250 Ohms

Refer to Figure 4-1 and the following steps to connect the Field
Communicator to a signal line 250 ohms or more of load resistance.

Do not make connections to the Field Communicator 's serial port, 4-20 mA signal lines, or
NiCad recharger jack in an explosive atmosphere. Explosions can result in death or serious
injury.

Using the supplied lead set, connect the Field Communicator in parallel to the
OCX 8800. Use any wiring termination points in the oxygen analog output
4-20 mA signal lin e.

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OCX 8800

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Figure 4-2. Signal Line Connections,
< 250 Ohms Load Resistance

Method 2, for Load Resistance < 250 Ohms

Refer to Figure 4-2 and the following steps to connect the Field
Communicator to a signal line with less than 250 ohms load resistance.

Do not make connections to the Field Communicator's serial port, 4-20 mA signal lines, or
NiCad recharger jack in an explosive atmosphere. Explosions can result in death or serious
injury.

1.

At a convenient point, break the oxygen analog output 4-20 mA signal
line and install the optional 250 ohm load resistor.

2.

Plug the load resistor into the loop connectors (located on the rear panel
of the Field Communicator).

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Field Communicator PC
Connections

There is an option to interface the Field Communicator with a personal
computer. Load the 375 Easy Upgrade Program ming Utility software into the
PC. Then link the Field Communicator to the PC through the IRDA Interface.
Refer to the proper Field Communicator documentation in regard to the PC
interface option.

Off-line and On-line Operations

The Field Communicator can be operated both off-line and on-line.
Off-line operations are those in which the communicator is not connected to

the OCX 8800. Off-line operations can include interfacing the Field
Communicator with a PC. (Refer to applicable documentation regarding
HART/PC applications.)

In the on-line mode, the communicator is connected to the oxygen 4-20 mA
analog output signal line. The Field Communicator is connected in parallel to
the OCX 8800 or in parallel to the 250 ohm load resistor.

The opening menu displayed on the LCD is different for on-line and off-line
operations. When powering up a disconnected (off-line) communicator, the
LCD will display the Main Menu. When powering up a connected (on-line)
communicator, the LCD will display the On-line Menu. Refer to the Field
Communicator manual for detailed menu information.

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HART MENU TREE This section consists of a menu tree for the Field Communicator. This menu is

specific to OCX 8800 applications.

Figure 4-3. HART Menu Tree
(Sheet 1 of 4)

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OCX 8800

4-6

LOOP TEST

37390039

00809-0300-

Figure 4-3. HART Menu Tree (Sheet 2 of 4)

(CONTINUED FROM

SHEET 1 )

STATUS

DIAG/SERVICE

(CONTINUED ON

SHEET 3)

HW STATUS

D/A TRIM

CALIBRATE

VERIFY CALIB

BLOWBACK

MAX TEMP

HEATER PID

Operate Mode
Status group 1

Status group 2
Status group 3
Status group 4
Status group 5

Status group 6
AO saturated

AO fixed

Model Number
Snsr Housing
CPLD REGS

Line Freq
Line Volt
PCN Counter
PCD Counter

O2 D/A Trim
COe D/A Trim

PERFORM
CAL

CAL
STATUS

CAL VALUES

PREV CAL
VALUES

FAILED CAL
VALUES

RESET CAL
CONST

Verify Calibration
Status
TimeRemain
O2
COe

BlBk State
Blowback

O2TempMax
COeTempMax
SBTempMax
BrdTempMax
CJCTempMax

O2 PID

COE PID

SB PID

O2 AO Saturated
COe AO Saturated

O2 AO Fixed
COe AO Fixed

BCSR0 BCSR3
BCSR1 BCSR4
BCSR2 BCSR5

O2 Loop Test

COe Loop Test

(procedures)

CAL METHODS
O2OutTracks
COeOutTracks
Cal Step
Cal Time
O2
COe

Cal Step
Cal Time

O2 Slope
O2 Const
O2 Snsr R
COe Slope
COe Const

Prev O2 Slope
Prev O2 Const
Prev O2 Snsr R
Prev COe Slope
Prev COe Const

Bad O2 Slope
Bad O2 Const
Bad COe Slope
Bad COe Const

Reset O2 CalConsts
Reset COe CalConsts

Status group 1
O2 T/C Open
O2 T/C Shorted
O2 T/C Reversed
ADC Failure
Line Freq Error
O2 Htr Failure
O2 Temp Very Hi
Board Temp Hi

Status group 2
O2 Temp Low
O2 Temp Hi
O2 Snsr Open
O2 Snsr R Hi
EEPRM Chksm Fail
O2 Htr Ramp Rate
COe Htr Ramp Rate
SB Htr Ramp Rate

Status group 3
Cal Failed
Cal Warning
SB T/C Open
SB T/C Shorted
SB Temp Low
SB Temp Hi
SB Temp Very Hi
ADC Ref Error

Status group 4
RTD Current Err
COe Temp Low
COe Temp Hi
COe Temp Very Hi
COe T/C Open
COe T/C Shorted
COe T/C Reversed
SB T/C Reversed

Status group 5
COe Htr Failure
SB Htr Failure
Line Voltage Low
Line Voltage Hi
Htr Relay Failed
Output Board Failure

Status group 6
O2 Slope Error
O2 Constant Error
O2 Cal Failed
COe Slope Error
COe Constant Error
COe Cal Failed

O2 Calibration
COe Calibration
O2 and COe Calib

O2 Prop
O2 Int
O2 DutyCyc
O2 SetPt
O2 Temp

COe Prop
COe Int
COe DutyCyc
COe SetPt
COe Temp

SB Prop
SB Int
SB DutyCyc
SB SetPt
SB Temp

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July 2018

OCX 8800

4-7

DEVICE

INFORMATION

HART
INFORMATION

S/W VERSION
INFO

Date

OUTPUT
CONDITION

O2 CALIB
PARAMS

COe CALIB
PARAMS

DEVICE
PARAMS

LOI
PARAMS

ANALOG
OUTPUT

ALARM
RELAY

BLOWBACK

O2 ANALOG
OUTPUT

COe ANALOG
OUTPUT

O2 AO Type

O2OutTracks

O2 Slope

User Intface

(CONTINUED FROM

SHEET 2)

BASIC SETUP

DETAILED
SETUP

(CONTINUED ON

SHEET 4)

37390040

-0300-4880, Rev AA

Figure 4-3. HART Menu Tree
(Sheet 3 of 4)

Descriptor
Message
Final asmbly num
O2 Sensor s/n
COe Sensor s/n

Tag
Poll addr
Dev id
Num req preams
Fld dev rev

Version
Chksum
Bld Num
Bld Date
Restart Cntr

O2 URV
O2 LRV
O2 Alarm Level

COe AO Type
COe URV
COe LRV
COe Alarm Level

Trig 1 Event
Trig 2 Event
Trig 3 Event
Alarm State

BlBk Enabled
BlBk Intrvl
BlBk Period
BlBk PurgeTm
BlBk State

O2 High Gas
O2 Low Gas
Gas Time
Purge Time
Solenoids
O2 CalIntv
O2NxtCalTm

COeOutTracks
COe Test Gas
Gas Time
Purge Time
Solenoids
COe CalIntv
COeNxtCalTm
COe Slope Warn

O2 Const
O2 T90
COe Slope
COe Const
COe T90
PCNC Enable
PCDC Enable

Luminance
Lockout Time
Revert Time

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July 2018

OCX 8800

4-8

O2 CALIB

COE CALIB

O2NxtCalTm

COeOutTracks

REVIEW

DEVICE
INFORMATION

HART
INFORMATION

CAL INFO

DEVICE
CONFIG

OUTPUTS
CONFIG

Manufacturer

Model

Date

Descriptor

Message

Final asmbly num

O2 Sensor s/n

COe Sensor s/n

Hardware rev

Software rev

O2 Slope
O2 T90

COE DEVICE

COe Slope

CONFIG

Trig 1 Event

Trig 2 Event

Trig 3 Event

BlBk Enabled

DEVICE CONFIG

BlBk Intrvl
BlBk Period

BlBk PurgeTm

PCNC Enable

PCDC Enable

Luminance

Lockout Time

Revert Time

O2 URV

O2 LRV

COe URV

COe LRV

O2 AO Type

COe AO Type

O2 Alarm Level

COe Alarm Level

37390041

Figure 4-3. HART Menu Tree
(Sheet 4 of 4)

(CONTINUED FROM

SHEET 3)

00809-0300-

Tag
Poll addr
Dev id
Num req preams
Fld dev rev
Universal rev

O2OutTracks
O2 High Gas
O2 Low Gas
Gas Time
Purge Time
Solenoids
O2 CalIntv

O2 DEVICE
CONFIG

COe Test Gas
Gas Time
Purge Time
Solenoids
COe CalIntv
COeNxtCalTm
COe Slope Warn

O2 Const

COe Const
COe T90

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OCX 8800

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D/A TRIM PROCEDURES O

D/A trim procedure using HART

2

Use the following procedure to perform the O

D/A trim procedure using the

2

Field Communicator. Refer to the HART menu tree, Figure 4-3.

NOTE

To select a menu item, either use the up and down arrow keys to scroll to the
menu item and press t he right arrow ke y or us e t he number keypad to se lect
the menu item number.

To return to a preceding menu, press the left arrow key.

1.

From the DIAG/SERVICE menu, select D/A TRIM. The Field
Communicator displays O2 D/A Trim.

2.

Press the right arrow key to start the procedure. (If you wish to exit D/A
Trim with no changes, select ABORT.)

3.

The Field Communicator displays WARNING: Loop should be
removed from automatic control. Remove the OCX 8800 from any
automatic control loops to avoid a potentially dangerous operating
condition and press OK.

4.

The Field Communicator displays Connect reference meter to O2
output.

5.

Remove the electronics housing cover.

6.

Refer to Figure 2-5. Connect a digital multimeter to read the milliamp
output from the O

D/A converter circuit. Connec t the p os iti ve lead to

2

the AOUT1+ terminal and connect the neg ative lead to the AOUT1­terminal. Then, press OK at the Field Communicator.

7.

The Field Communicator displays Setting Fld dev output to 4 mA.
Press OK. Read the O

millamp output at the digital multimeter. Enter

2

the reading at the Field Communicator and press ENTER. (Select
ABORT to exit without changes).

8.

The Field Communicator displays Setting Fld dev output to 20 mA.
Press OK. Read the O

millamp output at the digital multimeter. Enter

2

the reading at the Field Communicator and press ENTER. (Select
ABORT to exit without changes).

9.

The Field Communicator displays Setting Fld dev output to 4 mA.
Press OK.

10.

The Field Communicator displays Fld dev output 4.00 mA equal to
reference meter? Using the up or down arrow, select 1 Yes or 2 No
and Press ENTER. If No, the process repeats from step 6.

11.

The Field Communicator displays Setting Fld dev output to 20 mA.
Press OK.

12.

The Field Communicator displays Fld dev output 20.00 mA equal to
reference meter? Using the up or down arrow, select 1 Yes or 2 No
and Press ENTER. If No, the process repeats from step 7.

13.

The Field Communicator displays NOTE: Loop may be returned to

automatic control.

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July 2018

OCX 8800

4-10

00809-0300-

COe D/A trim procedure using HART

Use the following procedure to perform the COe D/A trim procedure using the
Field Communicator. Refer to the HART menu tree, Figure 4-3.

NOTE

To select a menu item, either use the up and down arrow keys to scroll to the
menu item and press t he right arrow ke y or us e t he number keypad to se lect
the menu item number.

To return to a preceding menu, press the left arrow key.

1.

From the DIAG/SERVICE menu, select D/A TRIM. The Field
Communicator displays O2 D/A Trim. Press the up or down arrow to
select COe D/A Trim.

2.

Press the right arrow key to start the procedure. (If you wish to exit D/A
Trim with no changes, select ABORT.)

3.

The Field Communicator displays WARNING: Loop should be
removed from automatic control. Remove the OCX 8800 from any
automatic control loops to avoid a potentially dangerous operating
condition and press OK.

4.

The Field Communicator displays Connect reference meter to
Combustibles output.

5.

Remove the electronics housing cover.

6.

Refer to Figure 2-5. Connect a digital multimeter to read the milliamp
output from the COe D/A converter circuit. Connect the positive lead to
the AOUT2+ terminal and connect the neg ative lead to the AOUT 2­terminal. Then, press OK at the HART communicator.

7.

The Field Communicator displays Setting Fld dev output to 4 mA.
Press OK. Read the COe millamp output at the digital multimeter. Enter
the reading at the Field Communicator and press ENTER. (Select
ABORT to exit without changes).

8.

The Field Communicator displays Setting Fld dev output to 20 mA.
Press OK. Read the COe millamp output at the digital multimeter. Enter
the reading at the Field Communicator and press ENTER. (Select
ABORT to exit without changes).

9.

The Field Communicator displays Setting Fld dev output to 4 mA.
Press OK.

10.

The Field Communicator displays Fld dev output 4.00 mA equal to
reference meter? Using the up or down arrow, select 1 Yes or 2 No
and Press ENTER. If No, the process repeats from step 6.

11.

The Field Communicator displays Setting Fld dev output to 20 mA.
Press OK.

12.

The Field Communicator displays Fld dev output 20.00 mA equal to
reference meter? Using the up or down arrow, select 1 Yes or 2 No
and Press ENTER. If No, the process repeats from step 7.

13.

The Field Communicator displays NOTE: Loop may be returned to

automatic control.

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OCX 8800

-0300-4880, Rev AA

Section 5 Calibration

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 5-1

Fully Automatic Calibration . . . . . . . . . . . . . . . . . . . . . . . . page 5-1

Operator - Initiated Autocalibration . . . . . . . . . . . . . . . . . page 5-3

Manual Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 5-3

OVERVIEW During a calibration, two calibration gases with known O

one calibration gas with a known COe concentration are applied to the OCX

8800. Slope and constant values are calculated to determine if the OCX 8800
is correctly measuring net concentrations of O
industrial process.

Before calibrating the OCX 8800, verify that the calibration gas parameters
are correct by setting the test gas values used when calibrating the unit. Refer
to Section 3, Configuration and Startup.

There are three calibration methods available to the OCX 8800; automatic,
operator-initiated automatic, and manual. Calibration commands and menus
can be accessed by HART/AMS.

and combustibles in the

2

concentrations and

2

FULLY AUTOMATIC
CALIBRATION

If the OCX 8800 is equipped with calibration solenoids, the unit can be
programmed to automatically calibrate without any operator action. Refer to
the following paragraphs for using HART/AMS to set up the OCX 8800 for
fully automatic calibration.

Autocalibration Setup using HART

NOTE

Automatic calibration is only available on units equipped with calibration
solenoids.

Use the following procedure to specify a time interval (in hours) at which the
OCX 8800 will automatically calibrate.

1.

From the DEVICE SETUP screen, select DETAILED SETUP.

2.

From the DETAILED SETUP screen, select O2 CALIB PARAMS or

COE CALIB PARAMS.

3.

If the unit is equipped with calibration solenoids and timed automatic
calibrations are desired, select Solenoids, then select Yes. Select No to
disable the calibration solenoids.

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4.

Select O2 CalIntrvl (O2 calibration interval) and enter the desired time
in hours between automatic O

calibrations. Select COE Callintrvl and

2

enter the desired time between automatic COe calibrations. To disable
automatic calibration for O

and COe, enter 0 for both CalIntrvl

2

parameters.

5.

If desired, the O2NxtCalTm and the COeNxtCalTm (next calibration
time) parameters can be changed to synchronize a calibration at a
specific day or time.

When setting automatic calibration times, CalIntrvl and NxtCalTm should be set so that O
and COe are NOT calibrated simultaneously.

2

NOTE

To select a menu item, either use the up and down arrow keys to scroll to the
menu item and press t he right arrow ke y or us e t he number keypad to se lect
the menu item number.

To return to a preceding menu, press the left arrow key.

6.

Select O2 CalIntrvl (O2 calibration interval) and enter the desired time
in hours between automatic O

calibrations. Select COE Callintrvl and

2

enter the desired time between automatic COe calibrations. To disable
automatic calibration for O

and COe, enter 0 for both CalIntrvl

2

parameters.

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OPERATOR - INITIATED
AUTOCALIBRATION

An operator can initiate an automatic calibration at any time provided that the
unit is equipped with calibration solenoids.

Autocalibration using HART

To initiate an automatic calibration using HART/AMS, perform the following
steps on the HART menu tree. Refer to Section 4, Using HART
Communications, for the HART menu tree.

1.

Select DIAG/SERVICE from DEVICE SET U P menu.

2.

Select CALIBRATION from the DIAG/SERVICE menu.

3.

Select PERFORM CAL from the CALIBRATION menu.

4.

Select CAL METHODS from the PERFORM CAL menu.

5.

From the CAL METHODS menu, select the type of calibration desired:

O2 Calibration, COe Calibration, or O2 and COe Calibration.

MANUAL CALIBRATION If a unit is not equipped with calibration solenoids, a calibration must be

performed by an operator following prompts from the unit. Refer to the
following paragraphs for manual calibration.

Manual O

To perform a manual O
use the following procedure. If necessary, refer to Section 4, Using HART

Communications, for the HART menu tree.

NOTE

To select a menu item, either use the up and down arrow keys to scroll to the
menu item and press t he right arrow ke y or us e t he number keypad to se lect
the menu item number.

To return to a preceding menu, press the left arrow key.

1.

2.

3.

4.

Calibration using HART

2

calibration using the Field Communicator or AMS,

2

From the DIAG/SERVICE menu, select CALIBRATION. From the
CALIBRATION menu, select PERFORM CAL.

From the PERFORM CAL menu, select CAL METHODS. Selec t O2
CALIBRATION to start O

In the first O2 Calibration screen, a Loop should be removed from
automatic control warning appears. Remove the OCX 8800 from any

automatic control loops to avoid a potentially dangerous operating
condition and press OK.

The main Calibration screen should look like the following. Press OK to
continue.

OCX: TAG NAME
STATUS: Idle
TIME REMAIN: 0s
O2: 0.4 %, 85.95mV
OK/NEXT to Select
ABORT/CANCEL to Exit

calibration.

2

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5.

From the SELECT ACTION screen, select START/NEXT CALSTEP to
continue calibration, select ABORT CAL to abort calibration or EXIT

CAL to exit calibration. Select one item from the list and press ENTER.

OCX: TAG NAME

SELECT ACTION

1.

START/NEXT CALSTEP

2.

ABORT CAL

3.

EXIT CAL

6.

When the Calibration Status is at the AppO2Low step, switch on O
Low Gas. Verify the O2 concentration measured matches the O2 LOW
GAS parameter in the Setup. Press OK when ready.

7.

Select Start/Next Cal Step to start applying the O2 Low Gas. The time
to apply the test gas is specified by the Gas Time.

8.

The Calibration Status should be automatically changed to FlowO2Low
and then ReadO2Low for a period of time. During this period, if an
attempt is made to go to the next calibration step by pressing OK and
selecting Start/Next Cal Step, you will be prompted with Operator step
command is not accepted at this time. The Next Cal Step command
is not accepted at this time.

9.

When ready, Calibration St atus wil l stop at the AppO2Hi. Switch off the
O

Low Gas and switch on the O2 High Gas. Verify the O2 concentration

2

measured matches the O2 HIGH GAS parameter in the Setup. Press

OK when ready.

10.

Select Start/Next Cal Step to start applying the O2 High Gas. The time
to apply the test gas is specified by the Gas Time.

11.

The Calibration Status should be automatically changed to FlowO2Hi
and then ReadO2Hi for a period of time. During this period, if an attempt
is made to go the next calibration step by pressing OK and selecting

Start/Next Cal Step, you will be prompted with Operator step
command is not accepted at this time. The Next Cal Step command

is not accepted at this time.

12.

When ready, Calibration Status will stop at STOP GAS. Switch off the
O

High Gas. Press OK when ready. Select Start/Next Cal Step to start

2

purging gas. The time to purge gas is specified by the Purge Time.

13.

When the Purge step is complete, the Calibration Status will be at IDLE
if the calibration is successful or CAL RECOMMENDED if the
calibration has failed. A Calibration Failed alarm will be set if the
calibration has failed.

14.

When calibration is complete. Select Exit Cal to exit the calibration
method.

2

Reference Manual

00809
July 2018

OCX 8800

5-5

-0300-4880, Rev AA

Manual COe Calibration using HART

To perform a manual COe calibration using the Field Communicator or AMS,
use the following procedure. If necessary, refer to Section 4, Using HART
Communications, for the HART menu tree.

NOTE

To select a menu item, either use the up and down arrow keys to scroll to the
menu item and press t he right arrow ke y or us e t he number keypad to se lect
the menu item number.

To return to a preceding menu, press the left arrow key.

1.

From the DIAG/SERVICE menu, select CALIBRATION. From the
CALIBRATION menu, select PERFORM CAL.

2.

From the PERFORM CAL menu, select CAL METHODS. Selec t COe
CALIBRATION to start COe calibration.

3.

In the first COe Calibration screen, a Loop should be removed from
automatic control warning appears. Remove the OCX 8800 from any
automatic control loops to avoid a potentially dangerous operating
condition and press OK.

4.

The main Calibration screen should look like the following. Press OK to
continue.

OCX: TAG NAME
STATUS: Idle
TIME REMAIN: 0s
COe: 0.20 ppm, 0.00 mV
OK/NEXT to Select
ABORT/CANCEL to Exit

5.

From the SELECT ACTION screen, select START/NEXT CALSTEP to
continue calibration, select ABORT CAL to abort calibration or EXIT

CAL to exit calibration. Select one item from the list and press ENTER.

OCX: TAG NAME

SELECT ACTION

1.

START/NEXT CALSTEP

2.

ABORT CAL

3.

EXIT CAL

6.

The unit samples reference air as the COe Low Gas. The Calibration
Status should automatically change to ReadCOLow for a period of time.
During this period, if an attempt is made to go to the next calibration
step by pressing OK and selecting Start/Next Cal Step, you will be
prompted with Operator step command is not accepted at this time.
The Next Cal Step command is not accepted at this time.

7.

When ready, Calibration Status will stop at the AppCOeHi. Switch on
the COe High Gas. Verify the COe concentration measured matches the
COe HIGH GAS parameter in the Setup. Press OK when ready.

8.

Select Start/Next Cal Step to start applying the COe High Gas. The
time to apply the test gas is specified by the Gas Time.

Reference Manual

4880, Rev AA

July 2018

OCX 8800

5-6

00809-0300-

9.

The Calibration Status should be automatically changed to FlowCOeHi
and then ReadCOeHi for a period of time. During this period, if an
attempt is made to go the next calibration step by pressing OK and
selecting Start/Next Cal Step, you will be prompted with Operator step
command is not accepted at this time. The Next Cal Step command
is not accepted at this time.

10.

When ready, Calibration Status will stop at STOP GAS. Switch off the
COe High Gas. Press OK when ready. Select Start/Next Cal Step to
start purging gas. The time to purge gas is specified by the Purge Time.

11.

When the Purge step is complete, the Calibration Status will be at IDLE
if the calibration is successful or CAL RECOMMENDED if the
calibration has failed. A Calibration Failed alarm will be set if the
calibration has failed.

12.

When calibration is complete. Select Exit Cal to exit the calibration
method.

Manual O

To perform a manual O

and COe Calibration using HART

2

and COe calibration using the Field Communicator or

2

AMS, use the following procedure. If necessary, refer to Section 4, Using
HART Communications, for the HART menu tree.

NOTE

To select a menu item, either use the up and down arrow keys to scroll to the
menu item and press t he right arrow ke y or us e t he number keypad to se lect
the menu item number.

To return to a preceding menu, press the left arrow key.

1.

From the DIAG/SERVICE menu, select CALIBRATION. From the
CALIBRATION menu, select PERFORM CAL.

2.

From the PERFORM CAL menu, select CAL METHODS. Select 02 &
COe CALIBRATION to start O

3.

In the first Calibration screen, a Loop should be removed from

and COe calibration.

2

automatic control warning appears. Remove the OCX 8800 from any
automatic control loops to avoid a potentially dangerous operating
condition and press OK.

4.

The main Calibration screen should look like the following. Press OK to
continue.

OCX: TAG NAME
STATUS: Idle
TIME REMAIN: 0s
O2: 0.4 %, 85.95mV
COe: 0.20 ppm, 0.00 mV
OK/NEXT to Select
ABORT/CANCEL to Exit

Reference Manual

00809
July 2018

OCX 8800

5-7

-0300-4880, Rev AA

5.

From the SELECT ACTION screen, select START/NEXT CALSTEP to
continue calibration, select ABORT CAL to abort calibration or EXIT

CAL to exit calibration method. Select one from the list and press
ENTER.

OCX: TAG NAME

SELECT ACTION

1.

START/NEXT CALSTEP

2.

ABORT CAL

3.

EXIT CAL

6.

When the Calibration Status is at the AppO2Low step, switch on O
Low Gas. Verify the O2 concentration measured matches the O2 LOW
GAS parameter in Setup. Press OK when ready.

7.

Select Start/Next Cal Step to start applying the O2 Low Gas. The time
to apply the test gas is specified by the Gas Time.

8.

The Calibration Status should automatically change to FIowO2Low and
then ReadO2Low for a period of time. During this period, if an attempt
is made to go to the next calibration step by pressing OK and selecting

Start/Next Cal Step, you will be prompted with Operator step
command is not accepted at this time. The Next Cal Step command

is not accepted at this time.

9.

When ready, Calibration Status will stop at AppO2Hi. Switch off the O
Low Gas and switch on the O2 High Gas. Verify the O2 concentration
measured matches the O2 HIGH GAS parameter in Setup. Press OK

when ready.

10.

Select Start/Next Cal Step to apply the O2 High Gas. The time to apply
the test gas is specified by the Gas Time.

11.

The Calibration Status should automatically change to FlowO2Hi, then
ReadO2Hi, and then ReadCOeLo for a period of time. During this
period, if an attempt is made to go the next calibration step by pressing

OK and selecting Start/Next Cal Step, you will be prompt ed with
Operator step command is not accepted at this time. The Next Cal
Step command is not accepted at this time.

12.

When ready, Calibration Status will stop at AppCOeHi. Switch off the O
High Gas and switch on the COe Gas. Verify the COe concentration

measured matches the COe TEST GAS parameter in the Setup. Press

OK when ready.

13.

Select Start/Next Cal Step to start applying the COe Gas. The time to
apply the test gas is specified by the Gas Time.

14.

The Calibration Status should automatically change to FlowCOeHi and
then ReadCOeHi for a period of time. During this period, if an attempt is
made to go the next calibration step by pressing OK and selecting

Start/Next Cal Step, you will be prompted with Operator step
command is not accepted at this time. The Next Cal Step command

is not accepted at this time.

15.

When ready, Calibration Status will stop at STOP GAS. Switch off the
COe gas. Press OK when ready. Select Start/Next Cal Step to start
purging gas. The time to purge gas is specified by Purge Time.

2

2

2

Reference Manual

00809
July 2018

OCX 8800

-0300-4880, Rev AA

Section 6 Maintenance and Service

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 6-1

OCX 8800 Removal and Installation . . . . . . . . . . . . . . . . . page 6-1

Repair Sensor Housing . . . . . . . . . . . . . . . . . . . . . . . . . . . page 6-8

Repair Electronics Housing . . . . . . . . . . . . . . . . . . . . . . . . page 6-28

Replace Tube Fittings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 6-34

OVERVIEW This section contains the procedures to maintain and service the OCX 8800.

Install all protective equipment covers and safety ground leads after equipment repair or
service. Failure to install covers and ground leads could result in serious injury or death.

OCX 8800 REMOVAL
AND INSTALLATION

It is recommended that the OCX 8800 be removed from the stack for all service activities.
The unit should be allowed to cool and be taken to a clean work area. Failure to comply may
cause severe burns.

Disconnect and lock out power before working on any electrical components. There may be
voltage up to 264 VAC.

Use the following procedures to remove or install the OCX 8800.

Reference Manual

4880, Rev AA

July 2018

OCX 8800

6-2

37390044

00809-0300-

OCX with
Remote Electronics

Figure 6-1. OCX with
Remote Electronics

Remove Sensor Housing

1.

Turn off power to the system.

2.

Shut off the test gasses at the cylinders and close the instrument air
valve.

3.

Disconnect the calibration gas, reference air, eductor air, and dilution air
lines from the sensor housing, Figure 6-1.

Duct

Stack

Sensor

Housing

Heater

Power Cable

Signal Cable

4-20 mA

Outputs

AC P ower

Input

Instrument Air

(Reference Gas)
Electronics
Housing

High O2 Test Gas
Low O

Test Gas

2

CO Test Gas

Reference Manual

00809
July 2018

OCX 8800

6-3

SENSOR HOUSING

NOTE: Wire colors shown are for cables

To

Ground

Screw

-

+ Heater

Power Cable

Signal Cable

BLU BLK

- O2

T/C O2

+

BLK GRN BLK

-

T/C CO

+

RED BLK

-

T/C

SB

+

WHT

BLK

EXC

-

-

CJC

+

BLK ORG

BLK

2

HTR 02

1

ORG

WHT

- CO REF

YEL

RED

2

HTR CO

1

+

BLK RED

-

CO ACT

+

WHT

BRN

2

HTR SB

1

YEL

BLU

EXC

+

GRN

37390028

-0300-4880, Rev AA

Figure 6-2. Sensor
Housing Terminals

4.

Remove the cover from the sensor housing to expose the sensor
housing terminal blocks, Figure 6-2.

5.

Disconnect the signal cable from the O2 and T/C terminal blocks, and
from the CO and CJC terminal blocks.

6.

Disconnect the heater power cable from the HTR terminal blocks.

7.

If moving the sensor housing to another work site, disconnect and
remove the power and signal cables from the sensor housing.

8.

Remove insulation to access the mounting bolts. Unbolt the sensor
housing from the stack and take it to a clean work area.

9.

Allow the sensor housing to cool to a comfortable working temperature.

supplied by Emerson.

Reference Manual

4880, Rev AA

July 2018

OCX 8800

6-4

00809-0300-

Install Sensor Housing

1.

Connect the test gas, reference air, eductor air, and dilution air lines to
the sensor housing.

2.

Remove the sensor housing cover.

3.

If removed, install the power and signal cables and the customer power
and signal conduits and wiring at the sensor housing.

4.

Connect the signal cable to O2 and T/C terminal blocks and to the CO
and CJC terminal blocks, Figure 6-2. Connect the heater power cable to

the HTR terminal blocks.

5.

Refer to Figure 6-1 and make sure all test gas lines and electrical
connectors are complete.

6.

Install the sensor housing cover.

7.

Restore power to the system. Allow OCX to reach normal operating
temperature before installing in a hot process stack.

8.

Insert and bolt the sensor housing in the stack and install insulation.

9.

Turn on the test gases at the cylinders and open the instrument air
supply valve.

Remove Remote Electronics Housing

1.

Turn off power to the system.

2.

Shut off the test gases at the cylinders and close the instrument air
supply valve, Figure 6-1.

3.

Disconnect the test gas and instrument air lines from the remote
electronics housing.

4.

Remove the cover from the electronics housing to expose the
electronics housing terminal blocks, Figure 6-3.

5.

Disconnect and remove the power leads from the AC power input
terminal block. Remove the ground lead from the ground stud.

6.

Disconnect and remove the O2 and COe signal leads from the 4-20 mA
signal output terminal block.

7.

If used, disconnect and remove the external relay leads from the alarm
output relay terminal block.

8.

Disconnect the signal cable leads from O2 cell and thermocouple
connector (J4), and from COe and CJC connector (J5), Figure 6-4.

9.

Disconnect the heater cable leads from the heater power connector
(J3).

10.

If moving the electronics housing to another work site, disconnect and
remove the power and signal cables and customer wiring conduits from
the housing.

11.

Remove the remote electronics housing from its mounting and move it
to a suitable work area.

Reference Manual

00809
July 2018

OCX 8800

6-5

{

AOUT1 -

37390013

-0300-4880, Rev AA

Figure 6-3. Electronics Housing
Terminal Blocks

NC

COM

NO

Alarm Output Relay

Terminal Block

COe Signal

#1

4-20 mA Signal Output

Terminal Block

O

2

Signal

AOUT2+

AOUT2 -

{

AOUT1+

EMI Filter

TOP VIEW

(1/2 SIZE)

Ground Stud

Earth Ground

Typical for Electronics and

Sensor Housing

#1

Customer

Wiring

Signal Port

3/4 NPT

Terminal

Block

G

Power Port

3/4 NPT

G

N L1

G

Ground

Stud

External Tooth

Lockwasher

Reference Manual

4880, Rev AA

July 2018

OCX 8800

6-6

1

GRN SHIELD

37390016

Figure 6-4. Remote Electronics
Housing Cable Connections

Heater Power

Connector (J3)

RED
BLK

WHT
BLK
GRN

BLK
BLU

BLK

#1

O2 Cell

& Thermocouple

Connector (J5)

Signal Cable

Heater
Power Cable

#1

YEL
RED
BLK
ORG
WHT
BLU

T/C CO+
T/C CO-

T/C SB+
T/C SB­T/C O2+
T/C O2-

O2 CELL+
O2 CELL-

2HTR CO

1HTR CO

2HTR O

1HTR O

2HTR SB

1HTR SB

SHLD

2

2

#1

#1 #1

YEL
BRN
BLK

RED
WHT
ORG

BLK

BLK

#1

To Ground

Screw

NOTE: Wire colors shown are for cables supplied

by Emerson.

To

Ground

Screw

COe Sensor

& CJC

Connector (J4)

EXC+
CO ACT+
CO ACT-

CO REF+
CO REF­CJC+

CJC­EXC-

00809-0300-

ELECTRONICS HOUSING

Reference Manual

00809
July 2018

OCX 8800

6-7

-0300-4880, Rev AA

Install Remote Electronics Housing

1.

Mount remote electronics housing on wall or pipe within distance of
signal and heater cables in use.

2.

Remove the electronics housing cover.

3.

If removed, install the power and signal cables and the customer power
and signal conduits and wiring at the electronics housing.

4.

Connect the signal cable leads to the O2 cell and thermocouple
connector (J4), and to the COe and CJC connector (J5), Figure 6-4.

5.

Connect the heater cable leads to the heater power connector (J3).

6.

Connect the line (L1 wire) to the L1 terminal, and the neutral (N wire) to
the N terminal on the AC power input terminal block, Figure 6-4.

7.

Connect the ground lead to the ground stud. Secure the connection with
two nuts. Attach a separate ground lead (G wire) from the ground stud
to the G terminal on the power input terminal block.

8.

If used, connect external relay leads to the alarm output relay terminal.

9.

Connect the test gas and ins tr um ent air li nes to the re mote electronics
housing. Connect the ca libr at ion gas l in e an d instr ument air line to the
remote electronics housing.

10.

Refer to Figure 6-1 and Figure 6-4. Make sure all test gas lines and
electrical connections are complete.

11.

Install the cover on the electronics housing.

12.

Turn on the test gasses at the cylinders and open the instrument air
valve.

13.

Restore power to the system.

Reference Manual

4880, Rev AA

July 2018

OCX 8800

6-8

00809-0300-

REPAIR SENSOR
HOUSING

Sensor Housing
Disassembly

Use the following procedures to remove damaged components from the OCX
8800 sensor housing and to install new replacement parts. Disassemble the
unit only as needed to replace damaged components. Use the assembly
procedures that apply to install replacement parts and reassemble the unit.

Remove Cover and Terminals Insulator

1.

Loosen screw (1, Figure 6-5) and slide locking clip (2) away from cover.
Retighten screw (1).

2.

With two hands or strap wrench, turn cover (3) counterclockwise to
loosen. Unthread and remove cover.

3.

Inspect cover o-ring (4) for wear or damage. Replace cover o-ring if
damaged.

4.

Unsnap terminal marking plates (5) and remove terminal insulator (6).

Reference Manual

00809
July 2018

OCX 8800

6-9

37390067

-0300-4880, Rev AA

Figure 6-5. Removal of O2 Cell
and Heater Strut Assembly

1.

Screw

2.

Locking Clip

3.

Cover

4.

O-ring

5.

Marking Plate

6.

Terminal Insulator

7.

Reference Air Tube

8.

Sensor Housing

9.

Heater Strut Assembly

10.

Gasket

11.

Screw

12.

Heater Clamp

13.

Heater Rod

9

11

10

12

3

7

4

5

6

8

13

2

1

Reference Manual

4880, Rev AA

July 2018

OCX 8800

6-10

HTR 02

O

Heater Wires

Thermocouple Wires

+

+

+

- O2

ORG

RED

GRN

YEL

T/C O2

+

+ +

-

T/C CO

+

O2 Cell and Heater Strut

Assembly

-

+

-

EXC

-

Sample

Thermo-

couple

Sample Block

Heater Rods

CJC

+

2

HTR 02

1

-

2

HTR CO

1

CO REF

+

-

HTR SB

1

CO ACT

+

+

EXC

Sensor

Housing T

erminals

Return Wire

37390068

Figure 6-6. O2 Cell,
Thermocouple, and
Heater Connections

O

Cell Wires

2

2

T/C SB

2

Remove O2 Cell and Heater Strut Assembly

00809-0300-

Block

1.

Remove reference air tube (7, Figure 6-5) from sensor housing (8).

2.

See Figure 6-6. Disconnect and tag O2 heater wires, O2 cell and return
wires, and thermocouple wires at the sensor housing terminals.

3.

Remove the O2 cell and heater strut assembly (9, Figure 6-5) from
sensor housing (8). Remove and discard gasket (10).

Remove Sample Block Heater Rods

1.

Disconnect sample block heater rod wires from terminal block. Refer to
Figure 6-6.

Reference Manual

00809
July 2018

OCX 8800

6-11

HTR 02

- O2

T/C O2

+

RED

-

YEL

T/C CO

-

CJC Sensor

T/C SB

+

NOTE: All wires
at these terminals
are in the CJC
current loop.

-

EXC

COe Sensor

+

2

HTR 02

1

-

2

HTR CO

1

CO REF

+

-

HTR SB

1

CO ACT

+

+

EXC

COe Heater Wires

COe Thermocouple Wires

Sensor

Housing T

erminals

RED WHT

BLU RED BLU RED WHT

37390018

-0300-4880, Rev AA

Figure 6-7. COe Sensor,
Thermocouple, and Heater
Connections

2.

Loosen screws (11, Figure 6-5) and rotate heater clamps (12) to release
heater rods (13). One heater clamp secures each heater rod.

3.

Slide sample block heater rods (13) out of housing (8).

Remove COe Sensor Assembly

1.

Disconnect COe heater, thermocouple, and sensor wires from terminal
blocks. Refer to Figure 6-7.

2.

Remove insulator (1, Figure 6-8).

2

COe Sensor Wires

+

­CJC

Assembly

Reference Manual

4880, Rev AA

July 2018

OCX 8800

6-12

Figure 6-8. Removal of
COe Sensor Assembly

8

10

12

14

7

11

00809-0300-

NOTE

For easier access, you may remove two screws from base of terminal block
mounting (13) and move terminal block assembly out of the way.

3.

Remove tubes (2, 3, and 4) from COe sensor assembly (5), eductor
fittings (12 and 15), and sensor housing (7).

4.

Unfasten bayonet connector of COe thermocouple (8) and remove
thermocouple.

5.

Loosen clamp screw of COe band heater (9) until heater rotates freely
on sensor holder (11).

4

3

5

1

9

2

15

6

13

16

1. Insulator

2.

Dilution Air Tube

3.

COe Extractive Tube

4.

Eductor Air Tube

5.

COe Sensor Assembly

6.

Eductor

7.

Sensor Housing

8.

COe Thermocouple

9.

Heater Insulator

10.

COe Band Heater

11.

Sensor Holder

12.

Eductor Elbow

13.

Terminal Block Mounting

14.

Eductor Holder

15.

Tube Fitting

16.

CJC Sensor

Reference Manual

00809
July 2018

OCX 8800

6-13

Sensor

Holder

Flat

Matchmark

Straightedge

Matchmark

37390035

-0300-4880, Rev AA

Figure 6-9. Alignment of
COe Sensor Assembly

6.

See Figure 6-9. Using straightedge on the sensor holder flat, as shown,
matchmark upper flange of sensor housing to show correct alignment of
sensor holder.

7.

With one wrench holding eductor elbow (12, Figure 6-8), and one
wrench on flats of sensor holder (11), unthread and remove COe sensor
assembly (5). Do not allow eductor elbow to turn.

8.

Slide band heater (10) and heater insulator (9) from sensor holder (11).

Reference Manual

4880, Rev AA

July 2018

OCX 8800

6-14

Eductor Flat

Straightedge

Matchmark

37390036

Figure 6-10. Eductor Alignment
Matchmarks

00809-0300-

Remove Eductor

The O

cell and heater strut assembly (9, Figure 6-5) and the COe sensor

2

assembly (5, Figure 6-8) must be removed before you start this procedure.

1.

Use straightedge to matchmark alignment of eductor flat and elbow, as
shown in Figure 6-10.

2.

Unscrew terminal block mounting (13, Figure 6-8). Move terminal block
mounting away from eductor (6).

3.

Unscrew eductor holder (14) with eductor (6) and fittings (12 and 15)
from sensor housing (7).

4.

Clamp flats of eductor (6) in jaws of bench vise.

Use heat resistant gloves when removing mating parts from the eductor. The mating parts
are bonded with a thread sealing compound. The compound softens at 450°F (232°C). The
heated parts can cause severe burns.

5.

Use a propane torch to heat the eductor (6) to 450°F (232°C), minimum.
Apply the heat near the screw threads.

6.

While heating the eductor (6), use wrench to apply removal torque to
elbow (12), eductor holder (14), or tube fitting (15) until the thread
sealant softens. Remove mating parts (12, 14, and 15).

7.

Use MEK or methylene chloride solvent to clean thread sealant residue
from the pipe threads of the mating parts. Refer to applicable MSDS
sheet for solvent handling precautions.

Reference Manual

00809
July 2018

OCX 8800

6-15

1

2

3

37390048

-0300-4880, Rev AA

Figure 6-11. Removal of Sample
and Exhaust Tubes

1.

Sensor Housing

2.

Sample Tube

3.

Exhaust Tube

4.

In Situ Filter

4

Remove Sample and Exhaust Tubes

Use heat resistant gloves when removing the probe tube or exhaust tube. The tubes are
bonded with a thread sealing compound. The compound softens at 450°F (232°C). The
heated parts can cause severe burns.

1.

Secure the sensor housing (1, Figure 6-11) in soft (plastic, wood, or
brass) vice jaws.

2.

Use a propane torch to heat the sample tube (2) or exhaust tube (3) to
450°F (232°C), minimum. Appl y the h eat near t he t hr e aded e nd of th e
tube.

3.

While heating the t ube, use a pipe wrench to appl y removal torque to
part being removed. Apply torque until the pipe thread sealant softens.
Remove and discard the used sample tube (2), exhaust tube (3), or
in-situ filter (4).

4.

Use MEK or methylene chloride solvent to clean thread sealant residue
from the internal pipe threads in the housing. Refer to applicable MSDS
sheet for solvent handling precautions.

Reference Manual

4880, Rev AA

July 2018

OCX 8800

6-16

37390032

Figure 6-12. O2 Cell, Heater,
and Thermocouple, Expl od ed
View

4

6

7
8

12

11

10

1. Screw
Cell

2. O

2

3. Heater Tube

4. Contact/

Thermocouple
Assembly

5. Gasket

6. Screw

7. Lockwasher

8. Return Wire

9. Heater Strut

Assembly

10. Spring Clip

11. Spring

12. Strut Bracket

00809-0300-

Do not remove the O2 cell unless you are certain it needs to be replaced. Removal may
damage the cell and platinum pad. Remove the O

cell for cell replacement only.

2

Disassemble O2 Cell and Heater Strut Assembl y

Do not attempt to replace the O2 cell until all other possibilities for poor
performance have been considered. If cell replacement is needed, order the

cell replacement kit (Refer to Section 8, Replacement Parts).

O

2

The O2 cell replacement kit contains an O2 cell and flange assembly, gaskets,
socket head cap screws, and anti-seize compound. The items are carefully
packaged to preserve precise surface finishes.

9

Do not remove items from the package until they are ready to be used.

1. Remove the four allen cap screws (1, Figure 6-12) from the O2 cell (2).
Remove the O2 cell. The cell flange has a notch that may be used to
gently pry the flange away from heater tube (3).

NOTE

The pad on the end of contact/thermocouple assembly (4) will sometimes
fuse to the O

cell (2).

2

2.

If the O2 cell is fused to t h e c ontact pad, push the O2 cell back into the
heater tube (against spr ing pres s ure) and qu ic k l y twist the O
cell and contact pad should separate. If the contact pad stays fused to
the cell, a new contact/thermocouple assembly (4) must be installed.

3.

Remove and discard gasket (5). Clean the mating surface of heater
tube (3). Remove burrs and raised surfaces with a block of wood and
crocus cloth.

Use care when handling contact and thermocouple assembly. The ceramic rod in this
assembly is fragile.

cell. The

2

3

5

Test Gas
Passage

Holes

2

1

4.

Remove screws (6), lockwashers (7), return wire (8), and heater strut
assembly (9).

5.

If replacing contact and thermocouple assembly (4), use a pencil to
mark location of spring clip (10) before removing. Squeeze tabs on
spring clip to remove. Retain spring clip and spring (11); replace if
damaged.

6.

While carefully handling new contact and thermocouple assembly (4)
lay old assembly next to new one. Transfer match marks to new
assembly.

7.

Carefully guide new contact and thermocouple assembly (4) through
strut bracket (12), spring (11), and spring clip (10) until spring clip
reaches pencil mark.

Reference Manual

00809
July 2018

OCX 8800

6-17

1

3 2

7 6

5 4

37390030

-0300-4880, Rev AA

Figure 6-13. COe Sensor,
Exploded View

Disassemble COe Sensor Assemb l y

1.

Carefully remove screws (1, Figure 6-13), lockwashers (2), and COe
sensor (3) from sensor holder (4). Remove and discard gasket (5).

2.

If damaged, use the following procedure to remove thermocouple
adaptor (6) from sensor holder (4):

a.

Use a propane torch to heat the thermoc ouple ada ptor to 450°F
(232°C), minimum.

b.

While heating, use a flat-head screwdriver to apply removal torque.
Apply torque until the pipe thread sealant softens. Remove and
discard the thermocouple adaptor.

c.

Use MEK or methylene chloride solvent to clean thread sealant
residue from the internal pipe threads in the sensor holder. Refer to
applicable MSDS sheet for solvent han dl ing precautions.

9

8

1.

Screw

2.

Lockwasher

3.

COe Sensor

4.

Sensor Holder

5.

Gasket

6.

Thermocouple Adapter

7.

Pre-Heater

8.

Plug

9.

Stainless Steel Balls

Reference Manual

4880, Rev AA

July 2018

OCX 8800

6-18

Sensor Housing
Assembly

00809-0300-

Always remove the stainless steel balls (approximately 200) from sensor holder before
removing or installing pre-heater. Turning pre-heater in t he sensor holder with the stainl ess
steel balls in place will cause permanent damage to the pre-heater.

3.

If pre-heater (7) is to be removed, clamp flats of sensor holder (4) in vise
jaws with plug (8) pointing up. Remove plug. Unclamp sensor holder
and pour stainless steel balls (9) into a container.

NOTE

Pre-heater should onl y be rem oved when pre-heater or sensor holder is
damaged. If removal is not requir e d, le ave t he pre-heater installed in the
sensor holder.

4.

Unthread and remove pre-heater (7).

5.

Use a cleaning solvent to thoroughly clean stainless steel balls (9) and
pre-heater chamber in sensor housing (4). Refer to applicable MSDS
sheet for solvent handling precautions.

Assemble COe Sensor Assembly

Always remove the stainless steel balls (approximately 200) from sensor holder before
removing or installing pre-heater. Turning pre-heater in t he sensor holder with the stainl ess
steel balls in place will cause permanent damage to the pre-heater.

1.

If pre-heater (7, Figure 6-13) was removed, apply pipe thread sealant
(Loctite #567) to the external pipe threads of pre-heater (7) and plug (8).
Do not apply sealant to the first turn of the pipe threads.

2.

Clamp flats of sensor holder (4) in vise jaws with pre-heater port
pointing up.

3.

Install and tighten pre-heater (7). Align pre-heater to flat of sensor
holder (4) as shown in Figure 6-14.

4.

Invert sensor holder (4, Figure 6-13) in vise and pour stainless steel
balls (9) into plug port. Press down on stainless steel balls and tap
sensor holder with plastic hammer to compact balls in pre-heater
chamber.

5.

Install and tighten plug (8).

Use care when installing the combustibles (COe) sensor. The RTD elements are fragile and
correct alignment in sensor holder is required for proper OCX operation.

6.

Lubricate and install COe sensor gasket (5). Apply anti-seize compound
to threads of screws (1).

Reference Manual

00809
July 2018

OCX 8800

6-19

37390034

-0300-4880, Rev AA

Figure 6-14. COe Sensor and
Pre-Heater Alignment

COe

SENSOR ASSEMBLY

THERMOCOUPLE

Sensor

Holder

Sensor

Holder

Flat

2 to 2-1/4 in.

(51 to 57 mm)

7.

Install COe sensor (3), lockwashers (2), and screws (1). Rotate flat of

TOP VIEW

COe Sensor

Flat

COe sensor (3) to center of sensor holder (4).

8.

Align COe sensor flat parallel to sensor holder flat, as shown in
Figure 6-14. Tighten screws (1, Figure 6-13).

9.

If replacing thermocouple adaptor (6), apply anti-seize to the pipe
threads. Install and tighten thermocouple adaptor.

Pre-Heater

Flat

Sensor

Holder

Flat

Assemble O

1.

See Figure 6-12. Assemble O2 cell (2), gasket (5), and heater tube (3).

Sensor and Heater Strut Assembly

2

Make sure the test gas passage holes line up with each other in all
components.

2.

Apply a small amount of anti-seize compound to the screw threads and
use screws (1) to secure assembly. Torque to 35 in-lbs (4 N·m).

3.

Carefully slide O2 heater strut assembly (9) into heater tube (3).

4.

Press down on the back plate of strut bracket (12) to ensure spring (11)
tension is present to hold contact pad against O

5.

Secure strut bracket (12) and return wire (8) with four screws (6) and

cell (2).

2

lockwashers (7). Make sure return wire (8) is tightly fastened. This is the
ground side connection for the O

2

cell.

Install Sample and Exhaust Tubes

1.

See Figure 6-11. Apply pipe thread sealant (Loctite #567) to the
replacement sample tube (2) or exhaust tube (3) pipe threads. Do not
apply sealant to the first turn of the pipe threads.

2.

Thread the sample tube (2) or exhaust tube (3) into the housing (1). Use
a pipe wrench to tighten the tube.

3.

If used, install and t ight en i n-situ filter (4).

Reference Manual

4880, Rev AA

July 2018

OCX 8800

6-20

37390047

00809-0300-

Install Eductor

Figure 6-15. Installation of
Eductor and COe Sensor

8

10

12

14

7

11

If installed, the O

cell and heater strut assembly (9, Figure 6-5) must be

2

removed from sensor housing (8), before you install the eductor.

1.

Apply pipe thread sea lant ( Loctite #5 67) to the ex terna l pipe thr eads of
eductor (6, Figure 6-15). Do not apply sealant to the first turn of the pipe
threads.

4

3

5

1

9

2

15

6

13

16

1. Insulator

2.

Dilution Air Tube

3.

COe Extractive Tube

4.

Eductor Air Tube

5.

COe Sensor Assembly

6.

Eductor

7.

Sensor Housing

8.

COe Thermocouple

9.

Heater Insulator

10.

COe Band Heater

11.

Sensor Holder

12.

Eductor Elbow

13.

Terminal Block Mounting

14.

Eductor Holder

15.

Tube Fitting

16.

CJC Sensor

Reference Manual

00809
July 2018

OCX 8800

6-21

Eductor Flat

Straightedge

Matchmark

37390036

-0300-4880, Rev AA

Figure 6-16. COe Sensor
Parts Alignment

2.

Install and tighten eductor (6) in eductor holder (14).

3.

Install and tighten elbow (12) on eductor (6). Male port of elbow must
point up and be in line with long axis of eductor.

4.

Apply anti-seize compound to the external pipe threads of eductor
holder (14).

5.

Install and tighten eductor holder (14) in sensor housing (7). Align
eductor with matchmarks, as shown in Figure 6-16.

Reference Manual

4880, Rev AA

July 2018

OCX 8800

6-22

37390058

00809-0300-

Install COe Sensor Assembly

Figure 6-17. Band Heater Height 1. Apply pipe thread sealant (Loctite #567) to the exposed pipe threads

of eductor elbow (12, Figure 6-15). Do not apply sealant to the first turn

0.37 in.
(9,4 mm)

COe Sensor

of the pipe threads.

2.

Screw sensor holder (11) onto eductor elbow (12).

3.

With wrenches on eductor elbow (12) and on flats of sensor holder (11),
tighten sensor holder. Do not allow eductor elbow to turn.

4.

Tighten sensor holder (11) to align outside flat with matchmark on
sensor housing flange, as shown in Figure 6-18.

The heater insulator prevents current leakage between the band heater and the sensor
holder. Failure to properly install the insulator may cause the device to trip a ground fault
interrupt circuit.

Band Heater

Insulator

5.

Wrap heater insulator (9) around sensor holder (11). Make sure the
insulator joint lines up with the band gap of the COe band heater (10).

6.

Slide COe band heater (10, Figure 6-15) up onto sensor holder (11). Do
not tighten the band heater at this time. Heater must rotate freely around
sensor holder.

7.

Check for proper height of COe heater thermocouple (Figure 6-14).
Thread bayonet connec tor up or down to adj ust height.

8.

Install and fasten thermocouple (8, Figure 6-15).

9.

Position band heater as shown in Figure 6-17 and Figure 6-18 and
tighten band heater clamp screw. The heater insulator (9) end joint must
line up with the band gap of the COe band heater (10).

Reference Manual

00809
July 2018

OCX 8800

6-23

Sensor

Holder

Flat

Matchmark

Straightedge

Matchmark

37390035

-0300-4880, Rev AA

Figure 6-18. COe Sensor
Holder Alignment

Reference Manual

4880, Rev AA

July 2018

OCX 8800

6-24

HTR 02

- O2

T/C O2

+

RED -

YEL

T/C CO

-

CJC Sensor

T/C SB

+

NOTE: All wires
at these terminals
are in the
current loop.

-

EXC

COe Sensor

+

2

HTR 02

1

-

2

HTR CO

1

CO REF

+

-

HTR SB

1

CO ACT

+

+

EXC

COe Heater Wires

COe Thermocouple Wires

Sensor

Housing T

erminals

RED WHT

BLU RED BLU RED WHT

37390018

Figure 6-19. COe Sensor,
Thermocouple, and Heater
Connections

00809-0300-

10.

Reconnect the COe sensor, thermocouple, and heater wires at the
sensor housing terminal blocks. Refer to Figure 6-19.

11.

Install and fasten the COe insulator (1, Figure 6-15) around COe sensor
assembly (5). All wiring must remain outside of the insulator.

12.

If terminal block mounting (13, Figure 6-15) was moved, reinstall with
two base mounting screws.

2

COe Sensor Wires

+

­CJC

CJC

Assembly

Reference Manual

00809
July 2018

OCX 8800

6-25

37390067

-0300-4880, Rev AA

Figure 6-20. Installation of O2 Cell
and Heater Strut Assembly

1.

Screw

2.

Locking Clip

3.

Cover

4.

O-ring

5.

Marking Plate

6.

Terminal Insulator

7.

Reference Air Tube

8.

Sensor Housing

9.

Heater Strut Assembly

10.

Gasket

11.

Screw

12.

Heater Clamp

13.

Heater Rod

9

11

10

12

3

4

5

6

8

2

1

Install Sample Block Heater Rods

13

7

1.

Before installing sample block heater rods (13, Figure 6-20), evenly coat
the heater rods with Watlube heater release agent.

Reference Manual

4880, Rev AA

July 2018

OCX 8800

6-26

HTR 02

O

Heater Wires

Thermocouple Wires

+

+

+

- O2

ORG

RED

GRN

YEL

T/C O2

+

+ +

-

T/C CO

+

O2 Cell and Heater Strut

Assembly

-

+

-

EXC

+

Sample

Thermo-

couple

Sample Block

Heater Rods

2

HTR 02

1

-

2

HTR CO

1

CO REF

+

-

HTR SB

1

CO ACT

+

+

EXC

Sensor

Housing T

erminals

Return Wire

37390068

Figure 6-21. O2 Cell,
Thermocouple, and
Heater Connections

00809-0300-

O

Cell Wires

2

2

T/C SB

Block

­CJC

2

2.

Install the heater rods (13), heater clamps (12), and screws (11).

3.

Reconnect the heater rod leads at the sensor housing terminal blocks,
(Figure 6-21).

Reference Manual

00809
July 2018

OCX 8800

6-27

-0300-4880, Rev AA

Install O2 Cell and Heater Strut Assembly

1.

Rub a small amount of anti-seize compound on both sides of new
gasket (10, Figure 6-20).

2.

Apply anti-seize compound to threads of O2 cell and heater strut
assembly (9) and sensor housing (8).

Stripped threads on the O2 cell a nd heater strut assembly can allow gas leakage. Gas
leakage can affect the O
and heater strut assembly.

measurements and calibration. Avoid over-tightening the O2 cell

2

3.

Install O2 cell and heater strut assembly (9) in sensor housing (8). Snug
up, but do not over-tighten the assembly.

4.

Reconnect the lead wires from O2 cell, heater, and thermocouple to the
sensor housing terminal blocks. Refer to Figure 6-21.

5.

Install reference air tube (7, Figure 6-20) in sensor housing (8). Make
sure that the open end of reference air tube extends into heater tube of

cell and heater strut assembly (9).

O

2

Install Terminals Insulator and Cover

1.

Install insulator (6, Figure 6-20) over uppermost terminal blocks.
Position one side of insulator against terminal blocks and snap terminal
marking plate (5) to mating stand-off.

2.

Position opposite side of insulator (6) and secure with related marking
plate (5).

3.

If removed, install cover gasket (4). Screw cover (3) onto sensor
housing (8). Tighten cover firmly.

4.

Align locking clip (2) with gap between cover ribs.

5.

Loosen screw (1) and slide locking clip (2) fully into gap between cover
ribs. Retighten screw (1).

Sensor Housing Leak Test

1.

Install 1/4 NPT cap on dilution air inlet fitting. Install a 1/4 NPT cap on
sample tube (2, Figure 6-11) or plug 1/4 NPT sample inlet port. Capped
or plugged ports must be air tight.

2.

If not in place, install exhaust tube (3, Figure 6-11) in exhaust port
according to the instructions provided.

3.

Connect a calibrated manometer to the CAL GAS inlet port.

4.

Connect and apply clean instrument air at 35 psig (241 kPa gage) to the
instrument air inlet fitting.

5.

Observe the manometer reading. The reading should be from 10 to 13
inches, Water Column. Locate and correct leaks if the reading is less
than 10 inches WC.

Reference Manual

4880, Rev AA

July 2018

OCX 8800

6-28

00809-0300-

REPAIR ELECTRONICS
HOUSING

Electronics Housing
Disassembly

Use the following procedures to remove damaged components from the OCX
8800 electronics housing and to install new replacement parts. Disassemble
the unit only as needed to replace damaged components. Use the assembly
procedures that apply to install replacement parts and reassemble the unit.

Remove Cover

1.

See Figure 6-22. Loosen screw (1) and slide locking clip (2) away from
cover (3). Retighten screw (1).

2.

With two hands or strap wrench, turn cover (3) counterclockwise to
loosen. Unthread and remove cover.

3.

Inspect cover gasket (4) for wear or damage. Replace cover gasket if
damaged.

Remove Flash PROM

Electrostatic discharge (ESD) protection is required to avoid damage to the electronic
circuits.

1.

Locate Flash PROM access port in electronics stack (5, Figure 6-22).

2.

Use suitable IC removal tool to remove Flash PROM (6).

Reference Manual

00809
July 2018

OCX 8800

6-29

37390037

-0300-4880, Rev AA

Figure 6-22. Removal/Installation of
Electronics Housing Components

1.

Screw

2.

Locking Clip

3.

Cover
O-ring

4.

5.

Electronics Stack

6.

Flash PROM

7.

thru 12. Not used

13.

Screw

14.

Lockwasher

15.

Solenoid Valve (3 way)

16.

Solenoid Valve

2

1

3

6

5

4

Remove Electronics Stack

14

13

15

16

1.

Unplug power cable, signal cable, and solenoid lead connectors from
terminals of electronics stack (5, Figure 6-22).

2.

Remove two screws (13) and lockwashers (14).

3.

Remove electronics stack (5).

Reference Manual

4880, Rev AA

July 2018

OCX 8800

6-30

37390083

Figure 6-23. Removal/
Installation of EMI Filter

00809-0300-

Remove Solenoid Valves

1.

Disconnect solenoid leads from mating terminal connector.

2.

Remove top nut of solenoid valve (15 or 16, Figure 6-22).

3.

Remove the solenoid coil assembly and washer.

4.

Unthread and remove solenoid valve base.

Remove EMI Filter and Terminal Block

1.

Disconnect EMI filter wiring (Figur e 6-23) at terminal block (3).

2.

Disconnect EMI filter wiring at AC power input terminal block on
electronic stack.

3.

Unbolt and remove EMI filter (1) from electronic stack.

4.

Remove ground wire (2) from terminal block (3).

5.

Unbolt and remove terminal block (3) from electronic stack.

Brown

Blue
Green

Green

1

2

3

Blue
Brown

Green

Electronics Housing
Assembly

Install EMI Filter and Terminal Block

1.

Install replacement EMI filter (1, Figure 6-23) and/or terminal block (3)
on electronic stack.

2.

Refer to wiring details in Figure 6-23. Connect EMI filter wiring and
ground wire (2) at terminal block (3).

3.

Connect EMI filter wiring at AC power input terminal block on electronic
stack.

Reference Manual

00809
July 2018

OCX 8800

6-31

37390060

-0300-4880, Rev AA

Figure 6-24. Flash PROM
Alignment

Corner

Bevel

Flash
PROM

Access

Port

Install Solenoid Valves

1.

Disassemble replacement solenoid valve (15 or 16, Figure 6-22).

2.

Install new solenoid valve base. Be careful not to overtighten.

3.

Install new washer and solenoid coil assembly and secure with nut.

4.

Connect the solenoid leads to the proper terminations on the solenoid
power terminal block (Figure 6-26).

Install Electronics Stack

1.

Install electronics stack (5, Figure 6-22) and secure with lockwashers
(14) and screws (13).

2.

See Figure 6-25 and Figure 6-26. Reconnect power cable, signal cable,
and solenoid lead connectors to electronics stack terminals.

Install Flash PROM

Electrostatic discharge (ESD) protection is required to avoid damage to the electronic
circuits.

1.

Locate Flash PROM access port in electronics stack (5, Figure 6-22).

2.

See Figure 6-24. Align Flash PROM (6, Figure 6-22) with mating
receptacle in access port of electronics stack as shown. Flash PROM
corner bevel must be in upper left corner of receptacle.

3.

Install Flash PROM (6).

Reference Manual

4880, Rev AA

July 2018

OCX 8800

6-32

1

GRN SHIELD

37390016

Figure 6-25. Electronics Housing
Cable Connections

Heater Power

Connector (J3)

RED

BLK

WHT
BLK
GRN

BLK
BLU

BLK

#1

O2 Cell

& Thermocouple

Connector (J5)

Signal Cable

Heater
Power Ca ble

YEL
RED
BLK
ORG
WHT
BLU

T/C CO+
T/C CO-

T/C SB+
T/C SB­T/C O2+
T/C O2-

O2 CELL+
O2 CELL-

#1

2HTR CO
1HTR CO
2HTR O
1HTR O
2HTR SB
1HTR SB

SHLD

NOTE: Wire colors shown are for cables supplied

by Emerson.

2
2

#1

#1 #1

To

Ground

Screw

COe Sensor

Connector (J4)

YEL

BRN

BLK

RED
WHT
ORG

BLK

BLK

To Ground

#1

Screw

EXC+
CO ACT+
CO ACT-

CO REF+
CO REF-
CJC+

CJC­EXC-

00809-0300-

& CJC

ELECTRONICS HOUSING

Reference Manual

00809
July 2018

OCX 8800

6-33

#1

#1

SOL

1
SOL

4
SOL

3
SOL

2

37390033

-0300-4880, Rev AA

Figure 6-26. Solenoid
Power Terminals

Install Cover

TOP VIEW

SOL 4

SOL 3

SOL 3

SOL 2

SOL 1

CO Test Gas

High O2 Test Gas

Test Gas

Low O

2

Instrument Air

1.

If removed, install cover gasket (4, Figure 6-22). Screw cover (3) onto
electronics housing. Tighten cover firmly. Align locking clip (2) with gap
between cover ribs.

2.

Loosen screw (1) and slide locking clip (2) fully into gap between cover
ribs. Retighten screw (1).

Reference Manual

4880, Rev AA

July 2018

OCX 8800

6-34

00809-0300-

REPLACE TUBE
FITTINGS

The OCX transmitter housings have special tube fittings that, if clogged or
damaged, must be replaced with the same type of fitting. The special tube
fittings have alpha or numeric codes etched on the fitting. Unetched tube
fittings are standard 1/4 inch, stainless steel fittings.

‘E’ Type Fitting

The ‘E’ type fitting is an eductor drive air fitting for the OCX 8800 general
purpose sensor housing. It is a 1/8 inch tube fitting with a built-in 0.011
inch restrictor orifice. It seats in a threaded base port inside the housing.

‘R’ Type Fitting

The ‘R’ type fitting is a reference air line fitting for the general purpose and
hazardous area sensor housings. This is a 1/4 inch tube fitting with a
built-in 0.007 inch restrictor orifice.

Remove Tube Fittings The OCX construction includes pipe thread sealant to seal fittings in all ports

that pass through to an outer wall of the instrument housing base. Use the
following instructions to loosen and remove tube fittings that are secured with
pipe thread sealant.

Use heat resistant gloves when removing a damaged tube fitting. The pipe threads are
bonded with a pipe thread sealant. The thread sealant softens at 450°F (232°C). The
heated parts can cause severe burns.

1.

Secure sensor housing (1, Figure 6-27) or electronics housing (2) in soft
(plastic, wood, or brass) vice jaws.

2.

To soften the pipe thread sealant, use a propane torch to heat the tube
fitting (3, 4, or 5) to 450°F (232°C), minimum.

3.

While heating the tube fitting, use a wrench to apply removal torque until
the pipe thread sealant softens. Remove and discard the used fitting.

4.

Use MEK or methylene chloride solvent to clean thread sealant residue
from the internal pipe threads in the housing. Refer to applicable MSDS
sheet for solvent handling precautions.

Reference Manual

00809
July 2018

OCX 8800

6-35

37390070

-0300-4880, Rev AA

Figure 6-27. Removal
of Tube Fittings

1.

Sensor Housing

2.

Electronics Housing

3.

Tube Fitting

4.

Tube Fitting (Type R)

5.

Tube Fitting (Type E)

2

5

3

4

1

3

3

3

Install Tube Fittings 1. Verify that the replacement tube fitting is identical to the item removed.

Special fittings are etched with code markings.

2.

Apply pipe thread sealant (Loctite #567) to the mating threads of the
tube fitting. Do not apply sealant to the first turn of the external pipe
threads.

3.

Install and tighten the tube fitting in the matin g port of sensor or
electronics housing.

Reference Manual

00809
July 2018

OCX 8800

-0300-4880, Rev AA

Section 7 Troubleshooting

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 7-1

Diagnostic Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 7-2

Fault Isolation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 7-3

Alarm Relay Events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 7-11

Install all protective equipment covers and safety ground leads after troubleshooting.
Failure to install covers and ground leads could result in serious injury or death.

OVERVIEW The troubleshooting section describes how to identify and isolate faults that

may develop in the OCX 8800. When troubleshooting the OCX 8800,
reference the following information.

Grounding It is essential that adequate grounding precautions are taken when installing

the system. Thoroughly check both the probe and electronics to ensure the
grounding quality has not degraded during fault finding. The system provides
facilities for 100% effective grounding and total elimination of ground loops.

Electrical Noise The OCX 8800 has been designed to operate in the type of environment

normally found in a boiler room or control r oom . Noise suppres sion circ uits
are employed on all f ield term inations and m ain inputs . W hen fault finding,
evaluate the electrical n ois e bei ng ge ner at ed i n the immediate circuitry of a
faulty system. Ensure all cable shields are connected to earth.

Electrostatic Discharge Electrostatic discharge can damage ICs in the electronics. Before removing or

handling the processor board or the ICs, ensure you are at ground potential.

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Total Power Loss In the event that the OCX 8800 will not power up at all, check the incoming

power supply to make sure power is being delivered to the OCX 8800. If the
incoming power supply is good, then check fuses F1 and F6 in the electronics
housing. Refer to Figure 7-1 for fuse locations.

Figure 7-1. Fuse Locations

Neutral (N)

10 Amp, 250 VAC

10 Amp, 250 VAC

O2 and COe Heater

4 Amp, 250 VAC

Sample Block Heater

8 Amp, 250 VAC

F6

F1

Line (L1)

F3

F4

DIAGNO S T I C ALARMS

Always install a blocking diode on the customers relay coil. Failure to install a blocking diode
may create noise spikes and cause faults in the OCX electronics.

The OCX 8800 is equipped with a set of alarm relay contacts on the
microprocessor board in the electronics housing. This set of dry contacts can
be connected to any customer supplied relay device, 30 VDC, 30 mA
maximum. A blocking diode is required on the customers relay coil.

Any fault condition in the OCX 8800 will trip the alarm relay. The optional SPA
with HART programmable alarm indicates LOW O2, HIGH COe, Calibration
Status, and Unit Failure. For more information refer to Appendix B - SPA with
HART Alarm.

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O2 cell degraded or failed

Check O2 cell impedance by reading the O2 Snsr R value via HART (see Figure 4-3,
sheet 2). If cell impedance is zero, replace O
impedance is less than 5000 ohms, check for cell housing ground fault. Repair ground
fault. If cell impedance is greater than 5000 ohms and no ground fault is indicated,
replace O

Ref Current Err (RTD excitation current error) (reference current should be 5.02 mA)

O2 Sensor R High (Oxygen sensor resistance high, > 5000 Ohms)
O2 Temp Hi (Oxygen sensor heater temperature high, > 750ºC)

COe Temp Hi (Combustion sensor heater temperature high, 310ºC)

-0300-4880, Rev AA

FAULT ISOLATION Faults in the OCX 8800 Transmitter are indicated by messages displayed on

the 275/375 Field Commiunicator. Fault indications that can appear are list ed
in Table 7-1, Troubleshooting.

If a fault is indicated on the Field Communicator, locate the fault indication in
Table 7-1. For each fault listed, there are related Probable Causes and
Recommended Corrective Actions. The Probable Causes are listed in the
order of most probable to least probable. Starting with the most probable
cause, inspect and test the unit to isolate the actual cause, then use the
Recommended Corrective Action listed to correct the problem.

Table 7-1. Troubleshooting

O2 Sensor Open (Oxygen sensor disconnected)

Probable Cause Recommended Corrective Action

Loose or open O2 cell circuit connection Check O2 cell circuit wires for breaks or loose connections. Repair lead wire break or

loose connections.

cell with cell replacement kit. If cell

2

cell with cell replacement kit.

2

Probable Cause Recommended Corrective Action

Loose or open lead or circuit wire connection for
COe sensor or CJC sensor current loop

COe sensor grounded Check resistance of COe sensor leads to ground per Figure 6-7. Replace COe sensor if

COe sensor failed Check resistance of both COe sensor elements per Figure 6-7. Replace COe sensor if

CJC sensor grounded Check resistance of CJC sensor to ground per Figure 6-7. Replace CJC sensor if

CJC sensor failed Check resistance of CJC sensor per Figure 6-7. Replace CJC sensor if resistance of

Probable Cause Recommended Corrective Action

High noise in OCX power supply Check power supply for line noise or voltage fluctuations. Install power line filter kit

Check all COe and CJC sensor current loop wiring per Figure 7-3 and Figure 6-7.
Correct wiring faults.

resistance is less than 10M Ohms.

resistance of sensor element is not between 100 and 250 Ohms.

resistance is less than 10M Ohms.

sensor is not between 100 and 150 Ohms.

(PN 6A00171G01) or high quality line filter for input power.

Probable Cause Recommended Corrective Action

High noise in OCX power supply Check power supply for line noise or voltage fluctuations. Install power line filter kit

Table continued on next page

(PN 6A00171G01) or high quality line filter for input power.

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SB Temp Hi (Sample block heater temperature high, > 190ºC)

O2 Temp Very Hi

COe Temp Very Hi (Combustion sensor heater over maximum temperature, > 400ºC)

SB Temp Very Hi (Sample block heater over maximum temperature, > 260ºC)
O2 TC Open (Oxygen sensor heater thermocouple open)

COe TC Open

00809-0300-

Probable Cause Recommended Corrective Action

High noise in OCX power supply Check power supply for line noise or voltage fluctuations. Install power line filter kit

(PN 6A00171G01) or high quality line filter for input power.

(Oxygen sensor heater over maximum temperature, > 820ºC)

O2 Htr Rmp Rate (Oxygen sensor heater over maximum temperature ramp rate)

Probable Cause Recommended Corrective Action

Incorrect O2 heater wiring Check O2 heater wiring per Figure 7-3 and Figure 6-6. Check the wiring at the heater

Incorrect O

Electronics package failure Replace electronics package.

thermocouple wiring Check O2 thermocouple wiring per Figure 7-3 and Figure 6-6. Check the wiring at the

2

and inside the electronics housing. Correct wiring fault. Perform Reset procedure in
Section 3, Configuration and Startup to continue operation.

thermocouple and inside the electronics housing. Correct wiring fault. Perform Reset
procedure in Section 3, Configuration and Startup to continue operation.

COe Htr Rmp Rate (Combustibles sensor heater over maximum temperature ramp rate)

Probable Cause Recommended Corrective Action

Incorrect COe heater wiring Check COe heater wiring per Figure 7-3 and Figure 6-7. Check the wiring at the heater

and inside the electronics housing. Correct wiring fault. Perform Reset procedure in
Section 3, Configuration and Startup to continue operation.

Incorrect COe thermocouple wiring Check COe thermocouple wiring per Figure 7-3 and Figure 6-7. Check the wiring at the

Electronics package failure Replace electronics package.

thermocouple and inside the electronics housing. Correct wiring fault. Perform Reset
procedure in Section 3, Configuration and Startup to continue operation.

SB Htr Rmp Rate (Sample block heater over maximum temperature ramp rate)

Probable Cause Recommended Corrective Action

Incorrect sample block heater wiring Check sample block heater wiring per Figure 7-3 and Figure 6-6. Check the wiring at

Incorrect sample block thermocouple wiring Check sample block thermocouple wiring per Figure 7-3 and Figure 6-6. Check the

Electronics package failure Replace electronics package.

the heater and inside the electronics housing. Correct wiring fault. Perform Reset
procedure in Section 3, Configuration and Startup to continue operation.

wiring at the thermocouple and inside the electronics housing. Correct wiring fault.
Perform Reset procedure in Section 3, Configuration and Startup to continue operation.

Probable Cause Recommended Corrective Action

O2 thermocouple or thermocouple circuit open Check O2 thermocouple and circuit wires for breaks or loose connections per Figure 7-3

and Figure 6-6. Repair breaks or loose connections or replace failed thermocouple.
Perform Reset procedure in Section 3, Configuration and Startup to continue operation.

(Combustibles sensor heater thermocouple open)

Probable Cause Recommended Corrective Action

Combustibles sensor thermocouple open Check thermocouple resistance (lead to ground) of reference and active thermocouples

per Figure 7-3 and Figure 6-7. If either thermocouple is open or shorted to ground,

Table continued on next page

replace combustibles sensor.