Honeywell Searchpoint Optima Plus User Manual

Operating Instructions

Searchpoint Optima Plus
Infrared Point Gas Detector

MAN0551 Issue 07 - 09/08
2108M0501

TOTAL ENVIRONMENTAL SOLUTIONS

Ensure that you read and understand these Operating
Instructions BEFORE installing or operating any part of the
Searchpoint Optima Plus.

Please pay particular attention to the Safety Warnings.

WARNINGS

1. For installations in the UK, the Code of Practice
SELECTION, INSTALLATION AND MAINTENANCE
OF ELECTRICAL APPARATUS FOR USE IN
POTENTIALLY EXPLOSIVE ATMOSPHERES should
be strictly observed. General recommendations are

given in BS5345: Part 1: 1989. Specic requirements
for ameproof (Type 'd'), intrinsically safe (Type 'i')
and increased safety (Type 'e') protection are given

in BS 5345: Part 3: 1979, BS 5345: Part 4: 1977 and
BS5345: Part 6: 1978 respectively.

For installations in North America, the National

Electrical Code (NFPA 70 - 1990) or later issues

should be strictly observed.

Elsewhere the appropriate local or national

regulations should be used.

2. The Code of Practice regarding SELECTION,
INSTALLATION, USE AND MAINTENANCE
OF APPARATUS FOR THE DETECTION AND
MEASUREMENT OF COMBUSTIBLE GASES

(OTHER THAN FOR MINING APPLICATIONS OR
EXPLOSIVES PROCESSING AND MANUFACTURE)

must be complied with. Refer to BS6959:1988 in the
UK or the appropriate local or national regulations.

3. Operators must be fully aware of the action to be
taken if the gas concentration exceeds an alarm
level.

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TOTAL ENVIRONMENTAL SOLUTIONS

CAUTIONS

1. Use only approved parts and accessories with the

Searchpoint Optima equipment.

2. To maintain safety standards, a planned maintenance

programme is strongly recommended. This
maintenance programme should take account of all

operational conditions and requirements. Maintenance

and service operations should only be performed by

personnel qualied to work upon Searchpoint Optima

Plus.

3. In order to maintain electrical safety, the unit must

not be operated in atmospheres with more than 21%
oxygen.

IMPORTANT NOTICES

1. Honeywell Analytics Limited can take no responsibility

for installation and/or use of its equipment if this is not

done in accordance with the appropriate issue and/or
amendment of the manual.

2. The user of this manual should ensure that it is

appropriate in all details to the exact equipment to be

installed and/or operated. If in doubt, the user should
contact Honeywell Analytics Limited for advice.

3. If further details are required which do not appear in

this manual, contact Honeywell Analytics Limited or
one of their agents.

4. The Searchpoint Optima System is certied for and

intended for use in potentially hazardous areas.
Install and use the Searchpoint Optima System in
accordance with the latest regulations.

Honeywell Analytics Limited reserve the right to change
or revise the information supplied in this document
without notice and without obligation to notify any person
or organisation of such revision or change.

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HELP US TO HELP YOU

Every effort has been made to ensure the accuracy in the
contents of our documents, however, Honeywell Analytics
Limited can assume no responsibility for any errors or
omissions in our documents or their consequences.

Honeywell Analytics Limited would greatly appreciate being
informed of any errors or omissions that may be found in the
contents of any of our documents and to this end we include
the form opposite for you to photocopy, complete and return
to us so that we may take the appropriate action.

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CONTENTS

Section Page

1. INTRODUCTION 10

1.1 General 10

2. INSTALLATION VARIATIONS 14

2.1 ATEX Units 14

2.2 UL and CSA Units Only 15

3. INSTALLATION 17

3.1 Unpacking 17

3.2 Siting and Orientation 17

3.3 Installation Guide 18

3.4 Attachments and Options 22

3.4.1 General 22

3.4.2 Standard Weather Protection 22

3.4.3 Sunshade/Deluge Protection 22

3.4.4 Storm Bafe 23

3.4.5 Dust Barrier 23

3.4.6 Calibration Cap 24

3.4.7 Gassing Cover 24

3.4.8 Flow Housing 25

3.4.9 Remote Gassing Cell 26

3.4.10 Junction Box Adaptor Plate 27

3.4.11 European Duct Mounting Kit 28

3.4.12 US Duct Mounting Kit 31

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CONTENTS

Section Page

4. ELECTRICAL CONNECTIONS 35

4.1 General 35

4.2 Analogue Connection 40

4.3 Digital Connection 40

4.4 +24V Power Connection 41

4.5 Earth Connection 41

5. COMMISSIONING 46

5.1 General 46

5.2 Commissioning Procedure using SHC-1
and Multimeter 47

5.2.1 Electrical Commissioning and Tests 47

5.2.2 Gas Response Testing 48

5.2.3 System Level Testing 49

5.2.4 Final Commissioning 51

5.3 Commissioning Procedure with Multimeter
Only 52

5.3.1 Electrical Commissioning and Tests

(Multimeter) Only 52

5.3.2 Gas Response Testing (Multimeter)

Only 54

5.3.3 System Level Testing 55

5.3.4 Final Commissioning (Multimeter) 56

5.4 Control System Setup 57

5.5 Functional Response Checking and
Calibration 57

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CONTENTS

Section Page

6. CALIBRATION 59

6.1 General 59

6.2 SHC-1 Hand-Held Interrogator 60

6.2.1 Connecting the Hand-Held
Interrogator 61

6.2.2 Hand-Held Interrogator Operating
Modes 62

6.2.3 Other Hand-Held Features 66

6.3 Calibrating the Controller 70

6.4 Calibrating the Sensor 73

7. ROUTINE CHECKS 81

7.1 General 81

7.2 Inspection and Functional Response Check
Procedure 81

7.2.1 Response Check Using Gassing Cover
and %LEL Concentration Gas 83

7.2.2 Response Check Using Remote
Gassing Cell & High %VV Gas 87

7.3 Inspection and Testing of Units Installed
in Ducts 92

7.4 Removal and Retting of Flow Housing 94

7.4.1 Removal of Flow Housing 94

7.4.2 Retting of Flow Housing 94

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CONTENTS

Section Page

8. FAULT FINDING 97

8.1 Troubleshooting 97

8.2 Diagnosis of Warning and Fault Messages 103

9. REPLACEMENT OF HAND-HELD
INTERROGATOR BATTERY 111

10. ORDERING DETAILS 113

11. SPECIFICATION 117

11.1 Searchpoint Optima Plus Specication 117

11.2 Cross Interference to Other Gases and

Vapours 124

11.3 Hand-Held Interrogator SHC-1

Specication 125

11.4 SHC Protection Device 126

11.5 Termination Unit DVC100 Specication 127

11.6 DX Termination Units Specication 128

12. CERTIFICATION DETAILS 130

13. WARRANTY 137

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Optical Block

WindowHeaterMirror

Heater

Gas Measuring Path

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1. INTRODUCTION

1.1 GENERAL

Searchpoint Optima Plus is designed for use in potentially
hazardous areas where it provides gas and vapour
detection which is free from poisoning and independent
of the presence of oxygen. The gas measuring parts of
Searchpoint Optima Plus are illustrated below.

Searchpoint Optima Plus uses the dual wavelength infrared
absorption principle to detect hydrocarbon gases and
vapours in various concentration ranges. The instrument
measures the number of molecules of the target gas in the
light path, which depends on the concentration of the target
gas. In addition to the relatively long and open measuring

chamber, Searchpoint Optima Plus can be tted with a short
enclosed ow through-cell as part of the chassis.
This is tted with separate inlet and outlet ports and

allows the application of high concentrations of gas for
test purposes.

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1. INTRODUCTION

Searchpoint Optima Plus is a micro-processor controlled,
Infrared Gas Detector with comprehensive built-in self-

diagnostic and fault nding facilities. An analogue 4 to

20mA output and digital communications are provided as
standard. Full two way communication allows calibration
and advanced self checking procedures to be used. To take
advantage of these features a Hand-Held Interrogator unit
may be connected to a Termination Unit or via the SHC
Protection Device to other junction boxes.

There are several different types of termination unit available:

Termination Unit Certication Output

DVC Type Termination Units

DVC100 (I) MK2 ATEX Isolated 4-20mA

DVC100 (M) MK2 ATEX Isolated 4-20mA and MODBUS

DX Type Termination Units

DVC100 (I) UL Isolated 4-20mA

DX100 (M) UL Isolated 4-20mA and MODBUS

Searchpoint Optima Plus contains no moving parts and
is available in a robust Stainless Steel explosion proof

enclosure which has a M25 (ATEX) or 3/4 NPT (UL and CSA)

mounting thread. The unit operates over a wide temperature
range and has a high degree of protection against dust
and water ingress. It is designed to operate in the most
arduous conditions and is supplied with a choice of weather
protection assemblies.

Searchpoint Optima Plus can be In-Duct Mounted, used

in Sampling Systems, is easily condence checked and

may easily replace an existing sensor. Provided that
existing cabling has three appropriately rated cores and the
installation is correctly screened and earthed, it should not

be necessary to replace the eld cables or junction boxes. (A
current to bridge converter may be required if the controller
cannot be congured to accept 4-20mA signals).

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1. INTRODUCTION

No special tools are required for installation. Correct
function of the detector as installed can be easily conrmed

using a Hand-Held Interrogator. Maintenance amounts to
occasional cleaning, zeroing and response checking for

condence.

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Existing Junction Box

Existing Cable

Optima

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2. INSTALLATION VARIATIONS

2.1 ATEX UNITS

Replacing existing Sensor
using existing Junction Box

and Cable (where suitable).

New Junction Box.
New Installations.

Optima

Optima

DVC Termination Unit

When used for calibration
and diagnostics purposes
the Hand-Held Interrogator
SHC-1 allows digital
communication with the
Optima. It is connected
to the Optima via the IS
Socket on the Termination
Unit DVC100 or via the
SHC Protection Device for
other junction boxes.

SHC-1

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3/4 NPT

Optima

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2. INSTALLATION VARIATIONS

2.2 UL AND CSA UNITS ONLY

UL and CSA Installations using
Explosion Proof
Junction Box.

Note: The Junction Box must be suitable for the hazardous

location in which the Optima is installed, check with the
Junction Box manufacturers literature as to suitability of
the box.

Optima

15

Field
Cable /
Conduit

Top

DX
Termination
Unit

Handheld
Interrogator
Socket

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3. INSTALLATION

WARNING

The Code of Practice regarding selection, installation
and maintenance of electrical apparatus for use in
potentially explosive atmospheres must be complied
with at all times.

Notes:1. The flying leads of the Searchpoint Optima Plus

must be mechanically protected and terminated
within a suitable terminal or junction facility.

2. When the detector is terminated in a hazardous

area a suitable UL listed enclosure must be used
(where appropriate).

3.1 UNPACKING

Carefully unpack the equipment, observing any instructions

that may be printed on or contained in the packaging, and
check the contents for transit damage.

3.2 SITING AND ORIENTATION

Searchpoint Optima Plus must
be mounted horizontally, as

this greatly reduces the risk of
obscuration due to build up of
dirt and moisture on the optical
surfaces.

Ensure the area immediately
surrounding the sensor is free
from objects that could hinder

the free ow of air around it.

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3. INSTALLATION

For monitoring lighter than air gases, Searchpoint Optima

Plus should be mounted above the area requiring protection.

For monitoring heavier than air gases it should be mounted
below the area to be protected.

When monitoring for heavier than air gases and mounting

the detector close to the oor, give consideration to the

potential of general site debris to build up on the detector.

Whether Searchpoint Optima Plus is installed in a

sheltered or an exposed location, it will require some form

of protection around the optics. The standard weather
protection combined with the sunshade/deluge protection
provides a high degree of protection of the detector, suitable
for many outdoor environments. Detectors operating in very
exposed locations where torrential rain or driven sea-spray

is routinely encountered can benet from the additional
protection provided by the Storm Bafe (2108D0280).

In areas where a high pressure jet may be used at close
range to wash down the surrounding location, it is advisable

to t some means of extra peripheral shielding,
Bafe or a shield plate.

eg. Storm

Accessories and attachments that can be used to improve
ease-of-use, performance and reliability in particular
installations are described in Section 3.4.

3.3 INSTALLATION GUIDE

Note: Installation of Searchpoint Optima Plus does not require

the unit to be opened. There are no user serviceable
parts inside the unit. Do not attempt to open or
dismantle the unit.

(1) Ensure that the correct attachments and accessories

for the application have been tted (see Section 3.4).

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3. INSTALLATION

(2) Check that the unit's 4-20mA current ouput is of the

correct type for the control card that it is connected to.

(Output type is on a label attached to white lead.)

Control card I/P: SINK Optima O/P: SOURCE

Control card I/P: SOURCE Optima O/P: SINK

(3) Secure the junction box onto the mounting surface,

using the Junction Box Adaptor Plate if required.

Searchpoint Optima Plus must be installed with it's
long axis horizontal in order for the standard weather
protection to operate correctly and to prevent water
from settling on the optical surfaces (see below).
The Optima unit should therefore only be screwed into
a threaded entry that is in a vertical wall of the junction
box.

3 7

(4) Feed the unit's wires carefully through the chosen

junction box entry and offer up it's threaded boss to

the entry. Screw the unit into the junction box until
it is secure and the semi-circular pattern of holes on
the front of the weather protection are on the bottom

(see below). For M25 entries, the boss should go right
through the wall and a locking nut should be tted;

whilst for 3/4 NPT entries, the boss should lock off on
the taper. If getting the holes in the right orientation

requires more rotation than is readily achievable,

remove the weather protection and rotate it through
180 degrees.

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3. INSTALLATION

(5) Using a multimeter, check that the voltages on the

+24V, and 4-20mA connections with respect to 0V are
less than +32V DC and that there is no 110V or 230V
AC around.

(6) Wire up the unit's electrical connections in

accordance with Section 4, taking note of the general
recommendations upon electrical installation.

(7)

Ensure that all cable entries are either used or plugged

in strict accordance with the relevant certication
requirements and local codes of practice.

(8) Verify the correct installation and operation of the unit

using the SHC-1 handheld interrogator. If a Termination
Unit has been used, testing can be performed without
the need for a hot work permit. Alternatively, if a basic
junction box has been used, electrical connections can
be made to the terminals inside the box using the SHC

adaptor. This will ordinarily require a hot work permit.

CAUTION

1. Searchpoint Optima Plus is certied and specied

for operation in ambient temperatures from -40°C
to +65°C. Operation of the unit outside of this

temperature range invalidates the certication and

the warranty. The unit records a non-erasable fault
log entry if it is operated at temperatures outside of

it's certied range.

If the ambient temperature that the unit could be

exposed to is likely to go outside of the certied

range it is recommended that the unit be located
elsewhere. The use of sampling systems can be
highly effective, especially in applications where
high temperatures are involved.

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3. INSTALLATION

2. Searchpoint Optima Plus is specied for operation

in environments where the rate of change of unit
temperature is less than 3°C / minute. Exceeding
this rate of change of temperature will cause the unit
to report a fault and may cause permanent damage.
If the conditions experienced by the unit are likely
to cause it to exceed this rate of change it is
recommended that additional preventative measures
are taken. The use of sampling systems is highly

effective; whilst shielding the unit from the prevailing
air ow can also be of benet.

3. Searchpoint Optima Plus has been vibration tested

to the levels specied in EN61779. If the vibration
levels on the installation exceed this, the unit's

reliability and integrity of operation will be degraded.
Do not install units in locations where the vibration
exceeds this level.

4. All optical gas detectors are eventually affected by
the build up of contaminants / condensation upon
their optical surfaces, normally resulting in faults
or warnings. In order to minimise the faults and
warnings caused by this it is recommended that
detectors are located as far away as is possible
from sources of airborne contaminants and steam /

condensation. Alternatively, the tting of shields or
the Storm Bafe (2108D0280) should be considered.

Sources of contamination / condensation that have
caused particular problems where appropriate
measures were not taken include generator / turbine
exhausts, steam lines / vents, drilling operation

(oilmist and mud spray) and unltered HVAC

installations. In dusty atmospheres, regularly check

for the build up of dust on the detector (refer to
section 7 Routine Checks).

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3. INSTALLATION

3.4 ATTACHMENTS AND OPTIONS

3.4.1 General

There are a number of attachments and accessories
available for use with Searchpoint Optima Plus. When
specifying Optima Plus for a particular application, it is
recommended that the user contacts Honeywell Analytics
or their representatives to determine the attachments and

accessories required. Covers, barriers and bafes provide

protection from a wide variety of environmental conditions.

Gassing covers, cells and ow housings provide the means

of applying gas to the detector. Mounting plates and remote
gassing kits enable the detector to be installed in ducts or in

places where obtaining routine access is difcult.

3.4.2 Standard Weather Protection (2108D0276)

Provides the best compromise
between response time and
protection. Suitable for indoor,
outdoor and duct mounting
applications.

3.4.3 Sunshade/Deluge Protection (2108D0275)

Supplied as standard
for all outside
applications. Provides
additional protection
against heavy rainfall,
wash downs and
direct sunlight.

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3. INSTALLATION

The Sunshade/
Deluge protection
should be clamped
around the base of

the Standard Bafe

Weather Housing with
the longer overhang
extending beyond

the Standard Bafe.

Ensure the clamp
does not cover the
gas venting slot of the

Standard Bafe.

3.4.4StormBafe(2108D0280,NotIllustrated)

The storm bafe provides increased protection against

a variety of environmental conditions and effects. It is
particularly effective against torrential rain and driven
sea-spray and is recommended for exposed installations
in maritime locations or areas where monsoon or tropical

rain conditions are experienced. The storm bafe can be
benecial in installations where steam drifting over the
detector from nearby plant is a problem. The storm bafe

can also be useful in some duct applications where the

inlets are not ltered and where high ow rates result in dirt

build-up or excessive cooling / condensation effects. This
accessory will reduce the detector’s speed of response.

3.4.5DustBarrier(2108D0259,NotIllustrated)

Fits under the standard bafe weather housing to prevent

the ingress of dust or oil mist which could contaminate the
optical surfaces. It also protects the optics in very wet or
exposed locations. This accessory will reduce the detector’s
speed of response.

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3. INSTALLATION

3.4.6 Calibration Cap (2108D0272)

Used to achieve accurate
calibration of Optima Plus on the

bench. Requires all protective

covers and attachments to be
removed from the measurement
chamber except for the
dust barrier. The calibration
procedures are described in
Section 6.

CAUTION

The Calibration Cap is designed for temporary use on
Optima whilst performing calibration. If the calibration

cap is left tted it will prevent ambient gas from reaching
the detector's measurement chamber. Ensure that

operators are aware that calibration caps must not be

left tted. In order to reduce the likelihood of this mistake

going un-noticed, the calibration caps are coloured red.

3.4.7 Gassing Cover (2108D0258)

Provides a convenient means
of applying gas to Optima Plus

units in the eld. Suitable for

functional test and calibration
purposes. Fits over the standard
weather protection, covering the
gas inlet slots. Gas is introduced
into the weather protection via
an injection tube on the gassing
cover. Injected gas diffuses
through the dust barrier into the
measurement chamber.
The response check procedure
is described in Section 5.4.

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3. INSTALLATION

CAUTION

The Gassing Cover is designed for eld testing and
calibration operations. If the cover is left tted it will
prevent ambient gas from reaching the detector's

measurement chamber. Ensure that operators are aware
that gassing covers must not be left on detectors.
Gassing covers are coloured red to reduce the likelihood
of this mistake.

3.4.8 Flow Housing (2108D0282)

For use in sampling system
applications.

The Flow Housing is fabricated
from solvent resistant Anodised
Aluminium.

The nozzles on the Flow Housing
are stainless steel with an outside
diameter of 6mm.

It is advised that sample gases and vapours are sucked

(negative pressure) rather than blown (positive pressure)
through this housing and that sample ow rates do not

exceed 2 litres per minute.

It is recommended that a ow failure indicator is tted
within the sampling system and the minimum ow rates are

suitable for the application and not less than 0.7 litres per
minute.

Note: response time will increase with a decreasing ow

rate.

The commissioning and calibration of an Optima equipped
with a ow housing is described in Sections 5 and 6.

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3. INSTALLATION

3.4.9 Remote Gassing Cell (2108B0240)

The Remote Gassing Cell (RGC) enables high

%V/V concentration gas to be applied remotely for

performing functional response checks (bump tests).

It is useful for units installed in ducts or in areas

where obtaining access is difcult. The RGC window

can be removed for cleaning.

Note:
During production, Optima Plus units are calibrated
with gas in the main measurement chamber, not in the
RGC. The RGC is not recommended for calibration
or high accuracy calibration testing purposes.

(The only exception to this is where units are being
used to measure high %V/V gases using the RGC as
a flow cell. In this instance, the units are production
calibrated with gas in the RGC.)

In order to avoid pressurisation effects, the ow rate should

be kept below 0.3 litres / minute.

The RGC option is factory tted.

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3. INSTALLATION

3.4.10 Junction Box Adaptor Plate (04200-A-1040)

The Junction Box Adaptor Plate provides a means of

increasing the spacing between the junction box's gland

entries and the mounting surface. This enables low gland
clearance junction boxes to be used without the Optima
Plus fouling on the wall / mounting surface. Junction boxes
which can be accommodated include the Hawke PL612 and
PJB1.

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3. INSTALLATION

3.4.11 European Duct Mounting Kit (04200-A-1015)

This kit enables Optima Plus to be conveniently mounted
inside a duct. Electrical connections are made to the
detector via a junction box which is mounted outside of the
duct. Using this kit, test gas can be non-invasively applied to
the detector via the gassing points provided.

250

Note 1: Dimensions
shown in mm.

250

125

63

63

125

188

250

Note 2: The cutout

250

in the duct should be

188

230mm x 230mm.

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Gassing

Points

Searchpoint

Optima

Duct

Mounting

Junction

Box

Bracket

Junction

Box

2108M0501

3. INSTALLATION

Notes: 1. In order to make use of the gassing points provided,

the Optima unit must be fitted with the Remote Gassing
Cell (2108B0240).

2. In offshore HVAC ducts or ducts without inlet
filtering, the use of the Storm Baffle (2108D0280) is
recommended.

3. CSA approval only applies for flow rates less than 5
m/s and does not cover the use of the Storm Baffle.

The duct mounting kit is assembled and installed onto a duct
as below:-

(1) Cut a square 230mm * 230mm hole in the duct wall. Drill
the holes required to attach the mounting plate to the duct

wall.

(2) Place the Optima unit on the side of the mounting plate

where the threaded bushes protrude and feed the wires
through the central hole.

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3. INSTALLATION

(3) Locate the unit's boss in the central hole and feed the
unit's wires through the chosen cable entry on the junction

box.

(4) Screw the unit into the junction box until the assembly is

secure with the mounting plate trapped between the box and
the Optima.

(5) Cut off the seals on the ends of the gassing cell inlet

tubes.

(6) Attach the gassing tubing to the ends of the gassing cell

inlet tubes.

(7) Fasten the mounting plate to the wall of the duct,

ensuring that the seal is compressed.

(8) Wire up the unit in accordance with the electrical

connection details in Section 4.

(9) Ensure that all cable entries are either used or plugged in
strict accordance with the relevant certication requirements

and local codes of practice.

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3. INSTALLATION

3.4.12 US Duct Mounting Kit

This kit enables Optima Plus to be conveniently mounted
inside a duct. Electrical connections are made to the
detector via a junction box which is mounted outside of the
duct. Using this kit, test gas can be non-invasively applied to
the detector via the gassing points provided.

Note 1: Dimensions shown in inches.

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3. INSTALLATION

The duct mounting kit is assembled and installed onto a duct
as below:-

(1) Cut a square 6" x 6" hole in the duct wall. Drill the holes
required to attach the mounting plate to the duct wall.

(2) Remove the cover from the junction box.

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3. INSTALLATION

(3) Feed the wires from the Searchpoint Optima Plus through

the weldment into the junction box. DO NOT SECURE THE
WIRES TO THE TERMINALS AT THIS TIME.

(4) Secure the sensor to the weldment.

(5) Attach the both tubing assemblies.

(6) Secure the mounting plate to the duct.

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CAUTION

The reliability and performance of instrumentation
installed at industrial and petrochemical facilities can

be strongly inuenced by the design and quality of the

electrical installation. It is strongly recommended that
before designing an electrical installation for Searchpoint
Optima Plus the electrical installation design authority
reads Section 4.1.

4.1 GENERAL

Searchpoint Optima Plus complies with the European EMC

requirements set out in standard EN50270:1999. In order

to maintain compliance with these standards it is essential
that the electrical installation of Searchpoint Optima Plus is
engineered appropriately.

Electrical installation standards and practices vary for
different countries, companies and hazardous area
approvals. It is the responsibility of the electrical installation
design authority to determine the applicable standards
/ practices and ensure compliance with them. When
designing electrical installations for Searchpoint Optima
Plus it is recommended that the design authority considers
the following:-

a. Ideally, the cases of units should not be connected

to electrically noisy (dirty) metalwork or conductors.
Preferably, the case (internally connected to the unit’s
green / yellow GND wire) should be connected to a
low noise instrument (clean) earth.

b. Preferably, the eld cable screen should be connected

to the unit’s green / yellow GND wire, providing a
single, continuous earth screen connected to a low

noise instrument (clean) earth. This connection must

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not be allowed to complete an earth loop or connect
instrument earth to safety earth.

c. If armoured cable is being used it is necessary to

prevent safety (dirty) earth from becoming connected
to instrument (clean) earth via the continuity plate in
the eld junction box. This is most easily achieved by
the use of insulating cable glands for the eld cable

entry.

d. For UL / CSA certied installations it is not practical to

isolate the unit’s case from safety (dirty) earth. The unit

and its junction box should be earthed in a manner

that complies with the certication requirements.

e. Any earth / ground bonding arrangement employed

should ensure that the maximum peak voltage

between the unit’s case earth and any eld cable

conductor is less than 350V. This includes conditions
where transient surge voltages are generated
by lightning or the switching of heavy electrical
plant. Surge voltages in excess of 350V can cause

permanent damage to the unit’s RFI lters and such

damage is not covered by warranty.

f. Earthing / grounding arrangements that employ

multiple protective earths or earth grids signicantly

increase the likelihood of large transient surge voltages
being generated between a unit’s case earth and the

eld cable conductors.

g. If it is suspected that the earth / ground bonding

arrangement employed will not prevent voltages

between the unit’s case earth and any eld cable

conductor from exceeding 350V it is strongly
recommended that surge suppression devices be

installed close to the unit. Suitable, certied surge

suppression devices include MTL’s TP-48-I-NDI and

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Pepperl & Fuchs’ FN-LB-1. Two of these devices are

sufcient to provide protection of the +24V, 0V,
4-20mA and RS485 (A) connections to a unit.

h. In general, correctly engineered star earthing

arrangements minimise earth current crosstalk and
noise, improving the reliability and performance of
instrumentation.

i. Low noise instrument (clean) earth should only be

connected to safety earth (usually dirty) at a single

point on a site / installation. This connection should
be made in such a manner that it does not introduce
noise onto the instrument earth.

j. The entire length of the eld cabling connected to

a unit should be screened / shielded. This screen /
shield should be connected to a low noise instrument

(clean) earth at a single end. (The screen / shield can

be connected to the unit’s earth in the junction box,
provided that this is isolated from all other earths /

grounds.)

k. For installations where the eld cable conductors run

through conduit or armour connected to safety (dirty)

earth, the conduit or armour should not be considered

as a sufcient screen / shield. A separate cable screen

/ shield, connected to a low noise instrument earth
should be employed.

l. The screens / shields of eld cabling should not be

connected in a manner that creates earth loops or
that will result in the screens / shields carrying large

currents from heavy plant or equipment.

m. The use of a single, screened / shielded cable for

each eld device ensures good screening / shielding

and reduces crosstalk. Cabling arrangements that use

a single cable to connect a number of eld devices

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compromise screening and increase the potential
for crosstalk. Such arrangements should only be
employed if the electrical installation design authority

is condent that this will not adversely affect the

reliability or performance of the system.

n. Any electrical interference induced onto the

conductors of a 4-20mA loop by the installation must
be kept below the levels necessary to comply with the

general requirements of EN61779 or other applicable
gas detector performance requirements / standards.

In practice, this means that peak noise currents
induced on the current loop should be no greater than
+/- 0.25mA. If peak noise currents larger than this are
induced on the current loop it is possible that spurious
gas readings, alarms and faults will be reported by the
control system monitoring the current loop.

o. The 0V rail of a control card / control system is often

connected directly to one side of the 4-20mA input’s
current sensing resistor. In such instances, any
electrical noise on the 0V rail can be considered to
be directly connected to the 4-20mA input. In order
to reduce the likelihood of such noise adversely
affecting the performance of a gas detection system it
is desirable to keep noise on the 0V rail to a minimum.

Safety earth / ground frequently carries a high level

of electrical noise and it is therefore advisable not to
connect the 0V rail to safety earth / ground. If the 0V
rail cannot be isolated from earth it is advisable to

either connect it to a low noise instrument (clean) earth

or through a path that presents a high impedance to
noise on the earth.

p. For installations in Europe, all electrical equipment

connected to the system should comply with
EN50270. For non-European installations, electrical

equipment connected to the system should comply

with applicable national or international EMC
standards.

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q. Searchpoint Optima Plus is designed to operate
correctly with supply voltages down to 18V. When
supplied with 18V, the maximum current drawn
by a single Searchpoint Optima Plus unit will be

250mA. The eld cabling conductors should have
sufcient cross sectional area to ensure that when

a unit is drawing 250mA the voltage reaching it does
not fall below 18V. For a control room voltage of 24V,
the maximum round loop cable resistance must
therefore be 24 Ohms. Round loop cable resistances
greater than those necessary to ensure that units
always receive at least 18V may result in unreliable
operation.

r. Ideally, the 24V supply reaching units should be free

from large transients, uctuations or high frequency
noise. Transients or uctuations which take the

supply voltage outside of the 18-32V range may
result in units switching off and re-booting.

s. In order to reduce the likelihood of radio frequency

interference affecting the operation of units it is
recommended that neither units nor their cabling are
installed in close proximity to the antennae of high
powered radio, radar or satellite communication

equipment.

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4.2 ANALOGUE CONNECTION

The unit’s analogue 4-20mA output is non-isolated and

shares the 0V return (black wire) connection with the DC
supply to the unit. The 4-20mA output is factory congured
for current source or current sink. The conguration is
identied by a label on the white 4-20mA output wire. The
connections to the unit are shown in the following gures.

Note: If using Searchpoint Optima Plus to replace an existing

catalytic sensor, a Current to Bridge converter must be
used.

4.3 DIGITAL CONNECTION

Searchpoint Optima Plus has a built-in RS485 digital
communications link. When using Termination Units, this link
can be connected to using the IS socket. For other junction
boxes, this link can be connected to using the SHC
Protection Device between the junction box terminals and
the SHC-1 Handheld Interrogator.

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The RS485 communications link is connected to the unit’s

orange (RS485(A)) and blue (RS485(B)) wires. If not used,

these wires must be separately terminated in a suitable
terminal or junction facility.

4.4 +24V POWER CONNECTION

The +24V DC power supply feed should be connected to the

unit via the red (+24V) and black (0V return) wires.

4.5 EARTH CONNECTION

An earth connection can be made to the unit in a number of
ways. When deciding how to earth the unit, consideration
should be given to the recommendations in section 4.1.
Physically, the earth connection can be made either via
the unit’s green/yellow earth wire, a metal nut between the
unit and the junction box’s earth continuity plate or a wire
connected to the unit’s external earthing point.

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42

Minimum Configuration for Retrofit Application (Optional Current to Bridge Converter)

MAN0551 Issue 07 - 09/08

Optional Modbus Output

(M version only)

IS

Socket

SHC-1

Termination Unit

(refer to indicidual Terminal Unit manuals

for specific electrical connections

2108M0501

4. ELECTRICAL CONNECTIONS

Configuration for Termination Unit with IS Socket and Hand-Held Interrogator

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44

Standard Configuration for Retrofit Application (With SHC Protection Device and Hand-Held Interrogator Option.)

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5. COMMISSIONING

5.1 GENERAL

WARNINGS

1. Alarm level signals may be intentionally generated
during the commissioning procedure. Ensure
that appropriate steps are taken to prevent the
unintended sounding of alarms or executive
actions. It is recommended that the control card
corresponding to the detector is isolated or inhibited
during the majority of the commissioning procedure.

2. In order to commission units installed with basic

junction boxes (i.e. not DVC100 or DX100), it will be

necessary to open the junction boxes under power.

This will require the appropriate safe operating

procedures to be employed.

3. The Optima Plus commissioning procedure
is best performed using an SHC-1 Handheld
Interrogator and a digital multimeter. Use of the
SHC-1 interrogator in combination with a multimeter
enables more comprehensive checks and testing

(Section 5.2). If however, an SHC-1 interrogator

is not available, basic commissioning can be

performed using just a multimeter (Section 5.3).

IMPORTANT

Searchpoint Optima Plus is supplied calibrated and

ready for use. It does not require calibration during

commissioning. Reference is made in this section to
a Gas Response Test. This is not a full calibration of
the sensor where zero and span values are set, but a
response test using a known concentration of gas to
validate the calibration of the sensor.

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5.2 COMMISSIONING PROCEDURE USING
SHC-1 AND MULTIMETER

5.2.1 Electrical Commissioning and Tests
(SHC-1 & Multimeter)

The procedure for verifying the electrical installation of the
unit is described below:-

(1) Before applying power to the unit, ensure that the eld

wiring is correct and all electrical connections are in
accordance with Section 4.

(2) Check that the unit’s 4-20mA output conguration is

correct for the type of control card that it is connected

to. (Source output for sink input, sink output for source
input. Unit’s output conguration is on label attached
to white wire.)

(3) Apply power to the control card connected to the unit

being commissioned. Wait for 1 minute to allow the
unit to initialise and stabilise. Using a multimeter set

on dc volts, measure the voltage across the red (+24V)
and black (0V return) connections. Nominally, this

voltage should be +24V. Voltages in the range +18V to
+32V are acceptable.

(4) Using either the IS socket on the Termination Unit,

or the SHC Protection Device, connect the SHC-1
Handheld Interrogator to the unit’s RS485 comms

link.(See Section 4.2 for SHC Protection Device
connections.)

(5) Select the DIAGNOSTICS option on the interrogator

menu and instruct the unit to display any ACTIVE

WARNINGS or ACTIVE FAULTS. (Diagnosis of FAULT /
WARNING codes is described in Section 8.)

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a. If there are any ACTIVE FAULTS, the cause(s) of

these must be identied and remedied before the

unit will become fully operational.

b. If there are any ACTIVE WARNINGS, the unit can

operate correctly despite the warning(s). However,

for reliable long term operation it is strongly
recommended that problems causing warnings are

xed before a unit is fully commissioned.

5.2.2 Gas Response Testing (SHC-1 & Multimeter)

The procedure for testing gas response as part of the
commissioning process is described below:-

(1) Select the DISPLAY mode on the SHC-1 Handheld

Interrogator. Check that the displayed gas reading
is 0.0% LEL. If the displayed gas reading is not

0.0% LEL, check that their is no background gas
concentration present, the optics are clean and free
from condensation and that the unit has been given

sufcient time to stabilise in it’s intended operating
environment. (For best results, it is recommended

that a unit is left powered up for one hour before

performing zero or span calibration / test activities.)

(2) Using the SHC-1 interrogator, put the detector into

INHIBIT (this will prevent gas readings from being
signalled on the 4-20mA output).

(3) Making use of either the gassing cover, or the remote

gassing cell (where tted), perform a functional gas

test. The procedure for performing functional gas
tests is detailed in Section 5.5. For a nominal 50%
LEL test gas concentration, the displayed reading

should be between 45% LEL and 55% LEL. (If

necessary, test gas concentrations between 20%LEL
and 95%LEL can be used with the same +/- 5% LEL

test tolerance.)

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Provided the displayed gas reading falls within the +/-5%
LEL test tolerance range, the functional gas test has been
completed satisfactorily.

CAUTION

If the displayed gas reading is not as expected, do not
proceed to re-calibrate the unit immediately. Instead,
double check the unit’s zero, the test gas and the gassing

technique. (IR gas detectors do not exhibit signicant

span drift and in most instances, any problem will be with
the zero or the test gas / technique.) Only consider
re-calibrating a unit when certain that the zero, test gas

and technique are correct and that the unit’s gas response
is signicantly out. The calibration technique is detailed in

Section 6.3.

5.2.3 System Level Testing (SHC-1 & Multimeter)

Conrmation of correct operation of the complete gas

detection system can be done using either test gas at the

required concentrations (Option B) or by FORCEing the

unit’s 4-20mA output under control of the SHC-1 interrogator

(Option A):-

CAUTION

When performing system level tests, ensure that any
resulting alarms or executive actions will not give rise to
unintended emergency drills or loss of production /
shut-down.

Note: It is assumed that the control system has been set up

for currents of 4mA and 20mA to read 0.0% LEL and
100% LEL respectively. If necessary, the FORCE 4-20mA
option can be used for setting up the control card. Be
aware that a 10 minute timeout applies to FORCE’d
4-20mA outputs.

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Option A) System Test Using FORCE’d 4-20mA

(1) The easiest way of performing system level functional

tests is to use the SHC-1 interrogator to FORCE the
4-20mA output to currents that are just above the
relevant alarm thresholds.

(2) The FORCE 4-20mA option is available from the

CALIBRATE menu. Using this option, FORCE the
4-20mA output to a current just above the A1 alarm
threshold. For example, with an A1 of 20% LEL, a

current of 7.5mA should sufce. Verify that the system

reports and responds as intended to this A1 signal.

(3) FORCE the 4-20mA output to a current just above the

A2 alarm threshold. With an A2 of 60% LEL, a current

of 14mA should sufce. Verify that the system reports

and responds correctly to this A2 signal.

(4) RELEASE the 4-20mA output. Conrm that the

system returns to normal, with no active alarms or
faults.

Option B) System Test Using Gas

If system level functional tests must be performed using gas,

test gas concentrations at least 5% LEL (ideally 10% LEL)
above each alarm threshold are required in order to allow for

system tolerances.

(1) Using either the gassing cover or the remote

gassing cell, apply test gas to the detector at the

concentration required to reliably exceed the A1

alarm threshold. For example, with an A1 alarm
threshold of 20% LEL, the minimum nominal test gas

concentration should be 25% LEL (ideally 30% LEL).

Verify that the system responds as intended to an A1
signal generated in this manner.

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(2) Apply test gas at the concentration required to reliably

exceed the A2 alarm threshold. With an A2 alarm
threshold of 60% LEL, the minimum nominal test gas

concentration should be 65% LEL (ideally 70%LEL).

Verify that the system responds correctly to an A2
signal generated in this manner.

5.2.4 Final Commissioning (SHC-1 & Multimeter)

The commissioning process is nished off as described

below:-

(1) Remove or disconnect any gas testing equipment

from the unit.

(2) Ensure that any test gas used is fully vented from the

measurement chamber or gassing cell. Verify that the

displayed gas reading returns to zero. (If the remote

gassing cell has been used, ensure that once vented,
it’s inlet tubes are sealed with the protective caps

provided (or a suitable alternative).)

(3) If required, remove the detector from INHIBIT.

(4) Select DIAGNOSTIC mode and verify that the unit has

no ACTIVE FAULTs or ACTIVE WARNINGs.

(5) Disconnect the SHC-1 interrogator. Replace the

junction box lid (where removed).

(6) When all of the relevant steps above are completed

satisfactorily, the unit has been commissioned and is
ready for operational use.

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5.3 COMMISSIONING PROCEDURE WITH
MULTIMETER ONLY

5.3.1 Electrical Commissioning and Tests
(Multimeter) Only

The procedure for verifying the electrical installation of the
unit is described below:-

(1) Before applying power to the unit, ensure that the

eld wiring is correct and in accordance with

Section 4.

(2) Check that the unit’s 4-20mA output conguration

is correct for the type of control card that the unit

is connected to. (Source output for sink input,

sink output for source input. The unit’s output

conguration is on a label attached to the white wire.)

(3) Apply power to the control card connected to the unit

being commissioned. Wait for 1 minute to allow the
unit to initialise and stabilise. Using the multimeter
set on dc volts, measure the voltage across the red

(+24V) and black (0V return) connections. Nominally,

this voltage should be +24V. Voltages in the range
+18V to +32V are acceptable.

(4) Remove power from the unit.

(5) Insert the multimeter set to read current (mA) in series

with the 4-20mA loop as follows:-

a. Current Sink Output

Remove the unit’s white 4-20mA output wire from

the terminal for the 4-20mA loop connection.
Connect the multimeter’s negative probe to the
white 4-20mA wire. Connect the multimeter’s
positive probe to either the +24V terminal or the
4-20mA loop terminal.

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b. Current Source Output

Remove the unit’s white 4-20mA output wire from

the terminal for the 4-20mA loop connection.
Connect the multimeter’s positive probe to the
white 4-20mA wire. Connect the multimeter’s
negative probe to either the 0V terminal or the
4-20mA loop terminal.

(6) Apply power to the unit and monitor it’s 4-20mA

output to conrm that it executes the correct power­up sequence as below:-

a. Output current of 0.0mA (0.0 to 0.5mA) for a period

of approximately seven seconds.

b. Output current of 2mA (INHIBIT current, 1.8 to

2.2mA) for a period of up to one minute whilst the

unit initialises and stabilises.

c. Output current of 4mA (ACTIVE zero gas current,

3.8mA to 4.2mA), which indicates that the unit is

operational and reading 0.0% LEL gas.

Note: If the unit is powered up in a non-zero

gas concentration, it will output a signal
corresponding to the gas concentration.

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5. COMMISSIONING

5.3.2 Gas Response Testing (Multimeter) Only

CAUTION

Without the SHC-1 interrogator it is not possible to
INHIBIT the gas detector. To avoid unintended executive
actions or alarms, it is recommended to either isolate
the detector itself or inhibit / isolate the corresponding
control card.

Functional gas testing can be performed using the
multimeter to monitor the 4-20mA output:-

(1) Isolate the detector by disconnecting the 4-20mA

output from the loop terminal and connecting the
multimeter to measure the 4-20mA current to either

the +24V (for current sink) or 0V (for current source).

Alternatively, if the control card has been isolated /
inhibited, connect the multimeter in series with the
4-20mA loop.

(2) Making use of either the gassing cover, or the remote

gassing cell (where tted), perform a functional gas

test as detailed in Section 5.5.

CAUTION

If the 4-20mA current is not as expected, double check

the unit’s zero, the test gas and the gassing technique.
(IR gas detectors do not exhibit signicant span drift and

in most instances the problem is with the zero or the

test gas / technique.) Only consider re-calibrating a unit
when certain that the zero, test gas and technique are
correct and that the unit’s gas response is signicantly

out. The calibration procedure is detailed in Section 6.3.

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For a nominal 50% LEL test gas concentration, the
4-20mA output current should be between 11mA and 13mA.
If the measured current falls within the correct range, the
functional gas test has been completed satisfactorily.

Note: Zeroing and calibration activities require use of the

SHC-1 interrogator.

5.3.3 System Level Testing (Multimeter)

If it is necessary to conrm the correct operation of the

complete gas detection system during commissioning

(without an SHC-1 interrogator), this can only be done using

test gases at concentrations which are at least 5% LEL

(ideally 10% LEL) above the relevant alarm thresholds.

(1) Remove power from the unit. Reconnect the unit’s

4-20mA output to the appropriate loop terminal (the
multimeter should still be in series to measure current).

(2) Making use of either the gassing cover, or the

remote gassing cell (where tted), introduce gas at
the required A1 test concentration into the unit. For

example, with an A1 alarm threshold of 20% LEL, the

minimum test gas concentration required is 25% LEL.

The corresponding 4-20mA output current should be

between 7.2mA and 8.8mA. Conrm that the correct

current and system responses are observed when the
A1 test gas is introduced into the unit.

(3) Introduce gas at the required A2 test concentration

into the unit. With an A2 alarm threshold of 60% LEL,

the minimum test gas concentration required is 65%

LEL. The corresponding 4-20mA output current should

be between 13mA & 15mA. Conrm that the correct

current and system responses are observed when the
A2 test gas is introduced into the unit.

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5.3.4 Final Commissioning (Multimeter)

The commissioning process is nished off as described

below:-

(1) Remove or disconnect any gas testing equipment

from the unit.

(2) Ensure that any test gas used is fully vented from the

measurement chamber or gassing cell. (If the remote

gassing cell has been used, ensure that once vented,
it’s inlet tubes are sealed with the protective caps

provided (or a suitable alternative)).

(3) Verify that after the initialisation and stabilisation

period (approximately 1 minute), the 4-20mA output
returns to 4mA nominal (between 3.8mA and 4.2mA).

(4) Remove power from the unit and disconnect the

multimeter from the 4-20mA loop. Connect the white
4-20mA wire back directly to the loop terminal.
Re-apply power to the unit.

(5) Verify that the unit returns to ACTIVE status and that

the gas reading displayed on the control card is

0.0% LEL.

(6) Replace the junction box lid.

(7) When all of the relevant steps above are completed

satisfactorily, the unit has been commissioned and is
ready for operational use.

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5.4 CONTROL SYSTEM SETUP

If the controller is in need of setting up, ie. for a 4 to 20mA

signal to show an equivalent reading eg. 0 - 100% fsd, this

may be done in two ways:

i) By using the Hand-Held Interrogator to FORCE the

required signal to the controller (see Section 6.4 of
this manual)

or

ii) With calibration gas applied to the sensor.

In each of these cases, a known signal is sent to the

controller, and the controller is set to show the equivalent

signal.

5.5 FUNCTIONAL RESPONSE CHECKING AND
CALIBRATION

Searchpoint Optima Plus is supplied factory calibrated and

when commissioning a unit, all that should be required to

verify correct operation is a functional response check.
The procedure for functional response checking is described
in Section 7 Routine Checks.

Where local regulations or working practices require gas

detectors to be calibrated when they are commissioned,
this should be performed in accordance with the procedure
described in Section 6 Calibration.

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6. CALIBRATION

6.1 GENERAL

Searchpoint Optima Plus is supplied factory calibrated for

a particular hydrocarbon gas (approximately 100 different
gas calibrations are currently available). Properly installed
and maintained, Optima Plus does not require routine
calibration. This operational benet is made possible

by the inherent stability of the IR absorption process

and the fully compensated optical conguration used.
In order to maintain condence in the continued correct
operation of elded Optima Plus units it is recommended

that a functional gas test is incorporated into the planned
maintenance procedure for the unit. In most applications
and installations, a planned maintenance / service interval
of 1 year is appropriate, although this will depend upon

site conditions and requirements. EN50073 and national

regulations should be observed.

Where site operating procedures or regulations require

routine calibration of gas detectors, this is possible using
the SHC-1 Handheld Interrogator and the gassing cover.
Care needs to be taken in order to ensure that routine

eld calibrations do not reduce the calibration accuracy
compared to the original factory calibration. (Factory

calibration is performed in more controlled conditions than

are readily achievable in the eld.)

Functional gas testing and calibration are made considerably
easier by use of the SHC-1 Handheld Interrogator. If an
SHC-1 is not available, basic functional gas testing can be
performed using just a multimeter to monitor the 4-20mA of
the unit being tested.

CAUTION

Searchpoint Optima Plus is a robust, ammable gas

detector, it is not an analyser. Where the performance or

features of an analyser are required, an analyser should

be used.

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LCD Display

Push Buttons

Hand-Held
Interrogator
Type SHC-1

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6. CALIBRATION

6.2 SHC-1 HANDHELD INTERROGATOR

The SHC-1 Handheld Interrogator is a portable, Intrinsically

Safe (IS) device which can be used to calibrate, test and

commission all of Honeywell Analytics Searchpoint and
Searchline optical gas detection products. The SHC-1
interrogator communicates with detectors via a digital RS485
link. Electrically, this link can be made either by using the IS

socket on the DVC100 / DX100 or by connecting the ying
leads on the SHC Protection Device (04230-A-1025) to the

appropriate junction box terminals.

WARNING

The IS certication of the SHC-1 Handheld Interrogator

only remains valid if it is used in conjunction with the
Termination Unit or the SHC Protection Device. Do not
attempt to connect the SHC-1 interrogator directly to
units, always use either the Termination Unit or the SHC
Protection Device.

Press ↵ and hold for three
seconds to switch on.

Press ↵ and esc together
and hold to switch off.

Unit powers down
auto-matically after
10 minutes to prolong
battery life.

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6.2.1 Connecting the SHC-1 Hand-Held Interrogator

6.2.1.1 Termination Units

When using a Termination Unit, the SHC-1 Handheld
Interrogator can be directly connected to the IS socket on
the bottom of the Termination Unit.

Termination Unit

Optima

IS Socket

SHC1

6.2.1.2 Other Junction Boxes
(Use of SHC Protection Device)

WARNING

The SHC Protection Device can only be used in a safe
area. ie. When a local safe area is achieved using a hot
work permit or other appropriate gas free permit.

Interrogator connections to units mounted on junction boxes
other than the DVC100 / DX100 can be made using the
SHC Protection Device. The procedure for using the SHC
Protection Device is as follows:-

(1) Remove the cover to the respective junction box.

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To Optima
Communications
Link Connections
in Junction Box

brown

blue

SHC Protection Device

To Hand-Held
Interrogator
SHC-1

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6. CALIBRATION

(2) Connect the brown lead of the SHC Protection Device

to the orange lead of the Optima communications link.

(3) Connect the blue lead of the SHC Protection Device to

the blue lead of the Optima communications link.

(4) Connect the Hand-Held Interrogator SHC-1 to the

SHC Protection Device connector.

Note: When transporting the SHC Protection Device in a

hazardous area, the SHC Protection Device must be
disconnected from the Hand-Held Interrogator.

6.2.2 Hand-Held Interrogator Operating Modes

The Hand-Held Interrogator version 4v0 is compatible
with Searchpoint Optima, Searchpoint Optima Plus and

Searchline Excel. To work with a specic product the correct

operating mode has to be selected as follows:

(1) Press ↵ to switch on the power.

(2) The display will rst show a title screen:

Z - SHC 1 Optima
Interrogator 4v0

The current operating mode is shown in the top right

of the display.

(3) Press esc and the display will show:

Z - SHC 1 Optima +
Interrogator 4v0

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(4) Press esc again and the display will show:

Z - SHC 1 Excel
Interrogator 4v0

If esc is pressed again the operating mode will

change to Optima and the different modes can be
stepped through again.

(5) When the display shows Optima + as the operating

mode wait three seconds for the main menu to be
displayed:

Main

Note: 1. The current operating mode is remembered when

the Hand-Held is switched off.

2. The operating mode can also be changed by
selecting the change mode option on the main menu.

Display

(6) Press

Main

(7) Press and the display will show:

Main

(8) Press and the display will show:

Main

and the display will show:

Calibrate

Diagnose

Gas Tables

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(9) Press and the display will show:

Main

(10) Press and the display will show:

Main

(11) Press and the display will show:

Main

Congure

Change Mode

Power Off

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Power Off

Main

Gas Tables

Main

Diagnose

Main

Calibrate

Main

Main

Show Gas

Gas Tables

Active Faults

Diagnose

Display

Calibrate

Congure

Main

Show Library

Gas Tables

Active Warns

Diagnose

Cal Sensor

Calibrate

Change Mode

Select Gas

Gas Tables

Self Test

Diagnose

Calibrate

Diagnose

Force 4-20

Calibrate

Soft Reset

This diagram shows all the Hand-held Interrogator

Software features. Use of the and keys to display

Normal 4-20

the individual menu options. The options are selected

by pressing ↵ and exited by press esc.

SHC-1 Hand-held Calibrator Menu Structure

Interrogator 4v0

Z- SHC1 Optima +

Display

Main

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6.2.3 Other Hand-Held Features

6.2.3.1 Display

Selecting this option from the main menu displays:

Optima + Methane

xx.x % LEL

The display shows the gas type, the gas reading and in the
bottom right a status indicator:

Rotating bar indicates a healthy active unit.

F indicates an active fault condition.

W indicates an active warning.

A indicates a gas concentration in excess of
the units internal alarm threshold

O indicates an active overrange.

I indicates inhibit condition.

Pressing

or ↵ changes the display to show:

Optima + S/W

4v0

The version of software currently installed within the

Searchpoint Optima Plus unit.

Pressing

, or ↵ will return the display to showing the

current gas reading.

Pressing esc exits the display option to the main menu.

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6.2.3.2 Calibrate

Display

The Display option on the Calibrate menu provides the same
information as the Display option on the Main menu except
the analogue output will be inhibited. This function is useful
if a response check is to be carried out and you do not wish
the gas reading to be reported on the analogue output.

Note: The rotating bar will not be shown on the gas reading

display when the analogue output is inhibited.

Normal 4-20

This action releases the analogue output. It should be
used if a communication error occurs while performing an
operation with the Hand-Held which Inhibited the analogue
output.

Note: The unit will release its analogue output automatically 10

minutes after it was Inhibited if no digital communication
occurs.

6.2.3.3 Diagnostics

Active Faults/Active Warning

Selecting one of these actions displays any fault or warning
conditions which are present in the unit. If more than one
condition is simultaneously present, these may be scrolled
through by pressing the

or keys.

FAULT conditions prevent the unit from working as a gas
detector and are always signalled on the analogue output as
0mA.

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WARNING conditions indicate that the unit is operating

close to the limits of its specied operating envelope. The

unit may go into fault in the near future. If a fault condition
is present in the unit while the active warnings are being
displayed, the top line of the display will show Fault Present.

Correct the Fault condition rst.

A list of fault and warning conditions and the actions
which should be taken to correct the problem are given
in section 8.

Self Test

This action instructs the unit to complete a self test cycle. If
a fault or warning condition was found in the unit, the Hand­Held display will show:

Error 13

Error in Unit

Details of the fault or warning can be viewed by selecting
the Active Fault/Active Warning menu option.

Soft Reset

Selecting this option forces the unit to reboot. It is
equivalent to switching the power to the unit off and
then on.

6.2.3.4 Gas Table

The Show Gas menu option displays the current gas type.
The Show Library action displays the part number and issue
of the data base within the unit which contains the details of
the diferent gasses which can be detected.

The Select Gas menu option allows the gas type of the unit
to be changed. The gas types available on the standard
unit are listed in Section 11.1.

The unit is inhibited while this action is performed. The unit
should be calibrated after the gas type is changed.

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6.2.3.5Cong

The Show Cong option on the Cong menu shows the

values of a number of key paramaters in the Searchpoint
Optima Plus. These may be scrolled through by pressing the

or keys.

OptimaPlusCongurationParameters

Conguration

Parameters

Auto Zero

Alarm
Threshold

Inhibit
Current

Warning
Current

Overrange
Current

Protocol
Address

Parameter
Title

Zero
Tracking

Alarm
Threshold

Inhibit mA

Warning mA

Overrange mA

Digital
Address

Purpose

Enables automatic zero tracking
function within the unit. Used only
in specialist applications, function
is normally disabled.

Sets a gas concentration thresh-

old (adjustable over the range

10% to 50% full scale, default

25%) beyond which the unit

considers a dangerous level of
gas is present. A fault will be
signaled if the output current can
not be driven to a value in excess
of this threshold.

Denes the output current for

Inhibit condition.

Denes the output current when a

warning is present.

Denes the output current when

the gas concentration exceeds
full scale.

Denes the protocol address of

the unit when connected into a
multi-drop digital network.
Used only in specialist
applications.

6.2.3.6 Power Off

Entering this menu and pressing ↵ turns off the Hand-held
Interrogator to preserve battery life.

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6.3 CALIBRATING THE CONTROLLER

This procedure allows the user to calibrate the controller by
FORCE’ing a known current out of the unit’s 4-20mA output.

Use of this technique enables calibration of the controller’s

0-100% fsd scale without the need for gas. The output can

be forced in the range 1.0 to 21mA (0.1mA resolution).

It is recommended that calibration of the controller is

performed at two points, ideally 4mA (0.0% fsd) and 12mA
(50% fsd). Provided that no background gas concentration
is present, the unit’s 4mA (0.0% fsd) output can be used to

calibrate the control cards zero point. The span calibration
of the controller can then be calibrated by FORCE’ing the

required current as follows:-

(1) Connect the Hand-Held Interrogator to the unit.

(2) Press ↵ to switch the power on, ensure the Hand-held

is in Optima + mode and wait ve seconds.

The display will show:

Main

(3) Press and the display will show:

Main

(4) Press ↵ and the display will show:

Calibrate

Display

Calibrate

Display

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(5) Press and the display will show:

Calibrate

(6) Press and the display will show:

Calibrate

This selects the FORCE'd 4-20mA routine which can

be used to calibrate the controller.

(7) Press ↵ and the display will show:

O/P 4-20 current

Cal Sensor

Force 4-20

4.0 mA

(8) Press

or to change the displayed mA value in

0.1mA steps:

O/P 4-20 current

12.0 mA

Choose the desired value.

(9) Press ↵ and the display will show:

Fixed: nn.nn mA
Press enter

where nn.nn is the current measured by the Optima

Plus diagnostic function. The analogue output is now

set to the selected value set in step (8). Specied
accuracy is ±1% FS (±0.2mA).

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(10) Calibrate the controller to display the correct reading

for the current being FORCE'd on the 4-20mA output.

(11) Press ↵ and the display will show:

Press Enter To
Release 4 - 20

Note: The unit will return to normal operation after 10 minutes

if no key is pressed.

(12) Press ↵ and the display will show for 3 seconds:

4 - 20 Released

The analogue output has now returned to normal

operation.

(13) Wait and the display will show:

Calibrate

Force 4-20

Returns to the Calibrate Menu.

(14) Press esc twice to return to the Main Menu:

Main

Display

(15) The Hand-Held Interrogator may be switched off by

pressing esc and ↵ together.

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6.4 CALIBRATING THE SENSOR

CAUTIONS

1. Searchpoint Optima Plus is supplied factory
calibrated for a particular hydrocarbon gas and

should not require routine gas calibration. In general,

this factory calibration will be more accurate than

what can be achieved in the eld. Only perform gas
calibration if this is required by local regulations or
if there is clear evidence of a signicant calibration

error. In most instances, the zeroing and functional
testing procedure described in Section 7 should be

sufcient to maintain a unit’s performance without

the need for gas re-calibration.

2. Ensure that the correct calibration gas and
concentration are used. The concentration of
calibration gas should be known to be accurate to
within +/-2.5% of the value declared on the cylinder
/ bottle.

3. It is important to present the calibration gas correctly
to the detector. Only use Searchpoint Optima Plus
gassing accessories as directed.

4. Searchpoint Optima, in common with other IR gas
detectors, measures the total number of target
gas molecules in it’s beam and hence readings
are directly related to the gas pressure in the
measurement path. Avoid pressurising calibration
gas inside the unit’s measurement path by keeping

gas ow rates below the maximum recommended

levels and ensuring that gas can freely vent to
atmospheric pressure. The maximum recommended

ow rates are 0.3 l / min for the remote gassing cell,

2 l / min for the gassing cover and 2 l / min for the

ow housing.

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5. Do not attempt to perform calibration during
periods of exceptionally low or high atmospheric

pressure. (Normally associated with unusual or

extreme weather conditions. Calibration is not
recommended during storms, very strong winds or

highly changeable weather conditions.)

6. Ordinarily, during production Optima Plus units
are calibrated with gas in the main measurement
chamber, which is where they will detect gas in
operational service. The response in the RGC
is not production calibrated. The RGC is not
recommended for calibration or for high accuracy

calibration testing. (The only exception to this is

where units are being used to measure high %V/V

gases using the RGC as a ow cell. In this instance,

the units are production calibrated with gas in the

RGC.)

7. Always allow unit’s to stabilise in the operating

environment for at least 30 minutes (ideally 1 hour)

before performing gas calibration.

Equipment Required:

Gassing Cover

Instrument Air (if a zero in ambient air cannot be guaranteed)
Calibration Span Gas (i.e. 2.2% V/V methane for 50% LEL
output if working in accordance with EN61779)

SHC-1 Handheld Interrogator

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To calibrate the sensor, proceed as follows:

(1) Connect the Hand-Held SHC-1, press ↵ to switch on

the power, check the Hand-held is in Optima + mode,

wait ve seconds and the display will show:

Main

(2) Press and the display will show:

Main

(3) Press ↵ and the display will show:

Calibrate

(4) Press and the display will show:

Display

Calibrate

Display

Calibrate

Cal Sensor

(5) Press ↵ and the display will show:

Inhibiting 4 - 20

Please Wait

This sets the analogue output to the inhibit level

(default 2mA) for the duration of the calibration
sequence.

(6) Remove weather protection and dust barrier. Check

that the optics are clean and dry. Clean / dry optics

if necessary. Ret the dust barrier and weather

protection.

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(7) Wait and the display will show:

Ensure Zero Gas

Press Enter

Note: If at this stage the zero reading in ambient air cannot

be guaranteed, fit the gassing cover over the weather
protection and apply instrument air at one litre/minute
for 30 seconds.

(8) Press ↵ and the display will show:

Processing Data

Please wait

After 10s the display will show:

Zero Calibrated

The new baseline (zero) is now set.

(9) Wait and the display will show:

Cal Span, Enter

Exit Cal, ESC

(10) Either:

a. press esc to end the calibration sequence without

carrying out a span calibration, or

b. press ↵ and the display will show:

Press Enter To

Select Gas Conc.

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This means set the gas concentration (ie. 50% LEL:

for 2.2% methane if working in accordance with

EN61779).

(11) Press ↵ and the display will show:

Span Gas

(12) Press or to change the displayed gas value

between 30 and 125%LEL (1% steps) to the value

being applied.

(13) Press ↵ and the display will show:

(14) Fit the gassing cover over the weather protection of

the Searchpoint Optima.

50.0 % LEL

Press Enter when

Stable: xx.x

(15) Apply span calibration gas at a rate of one litre/

minute and wait for reading to stabilise. This will take
approximately 30 seconds to 1 minute, depending

upon ow rate.

Press Enter when

Stable: xx.x

(16) Press ↵ and the display will show:

Processing Data

Please wait . . . .

After 10s the display will show:

Span Calibrated

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(17) Wait and the display will show:

Remove gas, Press

Enter: xx.x

(18) Remove the gassing cover from the weather

protection. Ensure the reading has returned to 00.0%
LEL.

(19) Press ↵ and the display will show:

Press Enter To

Release 4 - 20

Releases the analog output from 2mA (inhibit signal)

to normal operation (4mA).

(20) Press ↵ and the display will show for 3 seconds:

4 - 20 released

The analogue output has now returned to normal

operation.

(21) Wait and the display will show:

Calibrate

Cal Sensor

Returns to the Calibrate Menu.

(22) Press esc twice to return to the Main Menu:

Main

Display

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(23) The Hand-Held Interrogator may be switched off by

pressing esc and ↵ together.

Gassing Cover Fitted Over Weather Protection

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7. ROUTINE CHECKS

7.1 GENERAL

Searchpoint Optima Plus is designed to require minimal

routine maintenance and testing during use. Installed and

operated correctly, the only maintenance actions required

should be occasional cleaning and re-zeroing.

Continuous self-diagnostics ensure that if a unit develops a
problem, this is reported as a FAULT or WARNING. Warnings

are reported by a default signal of 3 mA (congurable).
Provided that a unit is reporting 4mA (or a congured
WARNING signal) it is an active gas detector.

Inspection and maintenance intervals vary depending upon

local regulations and requirements. EN50073 and national
regulations should be observed. If no specic requirements

exist, it is recommended that units are inspected and
functionally tested at twelve monthly intervals. Details of
the recommended routine inspection and functional test
procedure are presented in Section 7.2

7.2 INSPECTION AND FUNCTIONAL
RESPONSE CHECK PROCEDURE

The recommended procedure for inspecting and functionally
testing Searchpoint Optima Plus units is detailed below:-

Equipment Required:-

Gassing Cover (or Calibration Cap)
Test Gas (normally equivalent to 50% fsd)

SHC-1 Handheld Interrogator

Cleaning materials (soft cloth or cotton buds, mild detergent
or window cleaner)

(1) Inspect the Searchpoint Optima Plus unit, it’s junction

box and cabling for any signs of physical damage.

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(2) Connect the SHC-1 interrogator to the unit.

(3) INHIBIT the unit by selecting the DISPLAY option in

the CALIBRATE menu.

(4) Unscrew the two retaining nuts and remove the

Standard Weather Protection. Inspect the Standard
Weather Protection for damage or build up of debris

/ contaminants. If required, clean or replace weather

protection.

(5) Inspect the Dust Barrier and clean or replace if

required.

(6) Remove the Dust Barrier and inspect the optics.

(7) Clean any dust or contaminants from the optics using

mild detergent or window cleaner and a soft cloth or
cotton bud.

Note: If a remote gassing cell is fitted, the cell window can be

unscrewed and removed for cleaning purposes where
necessary. When replacing, ensure that the cell window
is fully screwed home (the effective thickness of the
gassing cell is reliant upon this).

CAUTIONS

1. Do not attempt to clean the optics using abrasive or
corrosive materials.

2. Do not attempt to clean the unit using a sand-blaster

or similar equipment.

3. Do not use concentrated organic solvents to clean
the unit. These substances contain hydrocarbons
which may give rise to gas readings when they
evaporate.

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(8) Ret or replace the Dust Barrier and Standard Weather

Protection.

(9) Verify that there are no ACTIVE FAULTs or WARNINGs

by checking that the ‘/’ line is present on the right
side of the CALIBRATE / DISPLAY screen. If there are
FAULTs or WARNINGs, the ‘/’ will be replaced with
either an F or a W.

(10) If ACTIVE FAULTs or WARNINGs are present,

investigate these by using the DIAGNOSTIC menu
options. Wherever possible, correct any ACTIVE
FAULTs or WARNINGs before proceeding to the next
stage.

Having completed the above steps, you are now ready to
perform a functional response check. Functional response
checks can either be performed using the Gassing Cover and
%LEL concentration gas or using the Remote Gassing Cell
and high %V/V gas. The procedures for performing functional
response checks are described in the following sections.

7.2.1 Response Check Using Gassing Cover and
%LEL Concentration Gas

Note: For best results when performing functional response

checks it is important to re-ZERO a unit before the
response check.

(1) For best results, allow the sensor to remain under

power for one hour prior to performing response check.

This allows the unit's temperature to stabilise in the

operating environment.

(2) Fit the Gassing Cover over the weather housing,

ensuring the gas entry slot at the base of the standard
weather protection is covered.

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(3) Ensure that there is a suitable zero gas inside the

unit’s main measurement chamber and the remote

gassing cell (if tted). Suitable zero gases include

fume/vapour-free atmospheric air, instrument air

and nitrogen. (In most outdoor or well ventilated
installations, atmospheric air will sufce for zeroing.

Instrument air or nitrogen should only be necessary

for poorly ventilated installations or where a signicant
hydrocarbon background is present or expected.)

(4) Select the CALIBRATE / CAL SENSOR menu option

and re-zero the unit. (Do not re-calibrate the unit’s
span gas response.)

(5) Select the CALIBRATE / DISPLAY menu option.

(6) Using the Gassing Cover, apply test gas to the unit.

Allow approximately 30 seconds to 1 minute for the
gas concentration in the measurement chamber to
stabilise.

(7) Monitor the DISPLAY’ed gas reading and conrm that

it is within +/-5% LEL of the anticipated reading. If the
reading is within +/- 5% LEL of what is anticipated, the

unit is denitely operating correctly. Do not consider

re-calibrating units with apparent “calibration errors”

less than +/- 5% LEL. Be aware that eld calibration

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and response checking techniques are not sufciently

accurate to determine whether such small “errors” are
genuine, or to correct them.

(8) If the DISPLAY’ed gas reading is within +/-10% fsd of

the anticipated reading, it is possible that there might
be a calibration error but it is still more likely that the
error will be due to the prevailing conditions or test

gas / technique. Before considering re-calibration,

double-check the following:-

a. The optics are clean and un-contaminated.

b. The unit has been correctly zeroed in a genuine

zero gas background.

c. The correct test gas and concentration are being

used for the range being tested.

d. The tolerance on the test gas concentration is

signicantly less than the apparent reading error.

e. There is adequate test gas in the cylinder.

(Cylinders that are nearly empty tend to read on
the low side.)

f. The test gas in the measurement chamber /

remote gassing cell is not being pressurised due to

high ow rates or blockages / restrictions.

g. The atmospheric pressure is not unusually high

or low.

h. The unit has had sufcient time to stabilise in it’s

operating environment. (At least 30 minutes, ideally
1 hour after any signicant change or power-up.)

i. An approved, Honeywell Analytics supplied

gas testing accessory is being used. (Either the

gassing cover, calibration cap or the remote

gassing cell.)

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If after checking the above, the error remains,

consider re-calibrating the unit in accordance with the
procedure detailed in Section 6.4.

(9) Errors in the DISPLAY’ed gas reading larger than +/-

10% fsd are rare. Where encountered, they are more
likely to be associated with the considerations listed

in (8) for double-checking than errors in the actual
unit's calibration. Ensure that all of the considerations

are fully checked before re-calibrating. If the apparent
calibration error is larger than +/-15% fsd, contact
Honeywell Analytics or their representatives for advice
before attempting re-calibration.

(10) Before releasing the detector from INHIBIT, ensure that

any test gas inside the unit’s measurement chamber
has been fully removed. This can be achieved either
by blowing instrument air / nitrogen through the
Gassing Cover, or by removing the Gassing Cover and

allowing the test gas to escape (this takes around 30
seconds).

(11) Release the detector from INHIBIT by selecting the

MAIN DISPLAY menu option.

(12) Provided that on the MAIN DISPLAY, the unit is

reading 0.0% LEL and the ‘/’ line is rotating, the unit
is operating normally and all tests and maintenance
activities have been completed.

If the ‘/’ line has been replaced by a W, there is an

ACTIVE WARNING in the unit, which should be
investigated and where possible cleared before leaving
the unit for operational use.

If the ‘/’ line is not rotating or has been replaced by an

F, there is an ACTIVE FAULT. The unit will not operate
with an ACTIVE FAULT. Use the DIAGNOSTICS menu
option to identify the cause of the FAULT and remedy
where possible.

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(13) Disconnect the SHC-1 interrogator from the unit.

(14) The functional response check has been completed

7.2.2 Response Check Using Remote Gassing Cell &
High %VV Gas

Note: 1. This only applies if the optional Remote Gassing Cell

has been selected and fitted.

2. The Remote Gassing Cell is designed to facilitate

functional response checking of units installed in
positions where obtaining access is difficult. The
RGC is not recommended for calibration or for high
accuracy calibration testing. During production,
Optima Plus units are calibrated with gas in the
main measurement chamber, which is where they
will detect gas in operational service. The response
in the RGC is not production calibrated. (The only
exception to this is where units are being used to
measure high %V/V gases using the RGC as a
flow cell. In this instance, the units are production
calibrated with gas in the RGC.)

3. The functional response check limits recommended

for this procedure include reasonable allowances
for the effects of atmospheric pressure, test gas
tolerances and test repeatability. These functional
response check limits are representative of what
the user should expect to achieve under typical field
conditions.

4. This procedure assumes the Searchpoint Optima

Plus has been calibrated for 0 - 100% LEL methane.

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CAUTIONS

1. In order to avoid pressurisation, gas should ow

through the remote gassing cell at no more than

0.3 litre/min.

2. Ensure that the exhaust pipe is not blocked since

this may pressurise the ow through the cell and

may cause permanent damage to the unit.

3. Never blow air from the lungs directly into the
remote gassing cell since the presence of any
foreign substances within the cell will adversely
affect the operation of the unit.

4. Always use a Flow Filter on the inlet of the remote
gassing cell when a remote gassing pipe is
permanently installed.

5. For other gases, contact Honeywell Analytics
Limited.

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Flow Through Gas Cell

High Concentration

(V/V cell) Nozzles

Dust Caps

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Equipment Required:

Flow Through Cell Gassing Kit, consisting of:

Lengths of plastic tube with In Line Particle Filter.

Cylinder of 50% v/v Methane.

Cylinder of nitrogen (zero gas).
Exhaust Pipe (at least one metre of plastic tube).

Multimeter.

(1) Remove the dust caps from the two pipes / tubes

leading to the Remote Gassing Cell Nozzles. (Whilst

the RGC is not being used for response checking, the
pipes / tubes leading to the RGC should be sealed
to prevent dirt / moisture ingress into the RGC. It is

assumed that the dust caps supplied tted to the
gassing cell nozzles will be used for this purpose.)

(2) Connect the outlet from the zero gas cylinder to the

pipe / tube leading to the RGC.

(3) Ensure that the exhaust pipe / tube coming from

the RGC is clear and that it vents well away from

the Searchpoint Optima. (If concentrated %V/V gas

leaving the exhaust pipe / tube gets into the main

measurement chamber it will signicantly affect the
readings obtained when using the RGC.)

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(4) Flush the RGC with zero gas for at least 30 seconds.

(5) Select the CALIBRATE / CAL SENSOR menu option

and re-ZERO the unit. (Do not re-calibrate the unit’s
span gas response.)

(6) Disconnect the zero gas and connect the high

concentration %V/V span test gas to the pipe / tube
leading to the RGC.

(7) Apply 50%V/V methane to the RGC at a ow rate of

0.3 litres / minute.

(8) Allow approximately 30 seconds to 1 minute for the

gas concentration in the RGC to stabilise.

(9) Monitor the DISPLAY’ed gas reading and conrm

that it is within +/-10% LEL of the anticipated reading

(57.5%LEL +/- 10%LEL for 50%V/V methane in the
RGC.). If the reading is within +/- 10% LEL of what

is anticipated, the unit is operating correctly. Do not
consider re-calibrating units with apparent errors less

than +/- 10% LEL. Be aware that eld calibration and
response checking techniques using the RGC are not
sufciently accurate to determine whether such errors

are genuine, or to correct them.

(10) If the DISPLAY’ed gas reading differs from the

anticipated reading by more than +/- 10% LEL, it is
possible that there might be a calibration error but
it is still more likely that any errors will be due to the

prevailing conditions, test gas or gassing technique.

Before considering re-calibration, double-check the
following:-

a. The optics are clean and un-contaminated.

b. The unit has been correctly zeroed in a genuine

zero gas background.

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c. The correct test gas and concentration are being

used for the range being tested.

d. The tolerance on the test gas concentration is

signicantly less than the apparent reading error.

e. There is adequate test gas in the cylinder.

(Cylinders that are nearly empty tend to read on
the low side.)

f. The test gas in the measurement chamber / remote

gassing cell is not being pressurised due to high

ow rates or blockages / restrictions.

g. The atmospheric pressure is not unusually high

or low.

h. The unit has had sufcient time to stabilise in it’s

operating environment. (At least 30 minutes, ideally
1 hour after any signicant change or power-up.)

i. An approved, Honeywell Analytics supplied gas

testing accessory is being used. (Either the gassing
cover, calibration cap or the remote gassing cell.)

If after checking the above, the error remains,

consider re-calibrating the unit in accordance with the
procedure detailed in Section 6.4.

(11) Before releasing the detector from INHIBIT, ensure

that any test gas inside the unit’s RGC has been fully
removed. This can be achieved by blowing instrument
air / nitrogen through the RGC for approximately
1 minute.

(12) Re-seal the pipes / tubes leading to the RGC using

the dust caps provided (or a suitable alternative).

(13) Release the detector from INHIBIT by selecting the

MAIN DISPLAY menu option.

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(14) Provided that on the MAIN DISPLAY, the unit is

reading 0.0% LEL and the ‘/’ line is rotating, the unit
is operating normally and all tests and maintenance
activities have been completed.

If the ‘/’ line has been replaced by a W, there is an

ACTIVE WARNING in the unit, which should be
investigated and where possible cleared before leaving
the unit for operational use.

If the ‘/’ line is not rotating or has been replaced by an

F, there is an ACTIVE FAULT. The unit will not operate
with an ACTIVE FAULT. Use the DIAGNOSTICS menu
option to identify the cause of the FAULT and remedy
where possible.

(15) Disconnect the SHC-1 interrogator from the unit.

(16) The functional response check has been completed.

7.3 INSPECTION AND TESTING OF UNITS
INSTALLED IN DUCTS

Obtaining access to units mounted in ducts can be more

difcult than for units in open installations. Ideally, one would

wish to perform all inspection and testing activities without
removing units or their mounting plates from the duct wall.

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The duct mounting kit makes it possible to interrogate
and functionally gas test units in-situ, which covers most
recommended maintenance and testing activities. However,
it is not possible to inspect or clean a unit whilst it is inside

the duct. The requirement to inspect and clean a unit varies

depending upon the conditions inside the duct:-

a. Clean / Dry Ducts: Where the conditions inside a duct

are clean and dry, the likelihood of contaminant or
condensation build-up on the dust barrier or optics
is relatively low. Provided that a unit is not reporting
any FAULTs or WARNINGs, it should not be necessary
to physically inspect it. Typical clean / dry duct

installations include ltered, onshore HVAC inlets and

outlets from clean plant / building areas.

b. Dirty / Damp Ducts: Where the conditions inside a

duct are dirty or damp, the likelihood of contaminant
or condensation build-up on the dust barrier or optics

is signicantly increased. It is therefore strongly

recommended that units are temporarily de-mounted
from the duct in order to perform inspection and
cleaning. Typical dirty / damp duct installations

include offshore HVAC inlets and un-ltered plant /

building inlets.

The procedure for testing and inspection of units installed
in ducts is essentially the same as that described in
Section 7.2.

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7.4 REMOVAL AND REFITTING OF FLOW

HOUSING

7.4 1 Removal of Flow Housing

Before the inspection check can be carried out on a

Searchpoint Optima Unit tted with a Flow Housing, the Flow

Housing must be removed as follows:

(1) Disconnect any pipework attached to the ow
housing.

(2) Using a ½ inch A/F open ended spanner, remove the

two black nuts which retain the ow housing. Keep

the O-ring seals which are below the retaining nuts.

(3) Slide the ow housing off the Optima. NB: This may

require some force due to the friction of the O ring.

(4) The window and mirror can now be inspected and

cleaned if necessary.

7.4.2RettingofFlowHousing

To ret the ow housing, proceed as follows:

(1) Check the window and mirror are free from

contamination.

(2) Ensure that the large sealing O ring, in the body of

the ow housing, and the two small O rings, which

go below the retaining nuts, are clean and in good
condition. Replace if in doubt.

(3) Slide the ow housing over the end of the

Searchpoint Optima and push until the ow housing
is rmly seated.

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(4) Place the small O-rings on the threaded pipes which

are used to secure the ow housing. Fit the retaining

nuts to the threaded pipes and tighten them down.

(5) Ensure that the main seal and the seals below the

retaining nuts are fully compressed and providing a
good seal.

(6) Reconnect any pipework that was attached to the

ow housing.

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8. FAULT FINDING

8.1 TROUBLESHOOTING

The table below describes some possible faults and problems that can
be encountered and their most likely causes and remedies. The user

should be aware that there are often signicant differences between what

appears to be the problem and the actual problem when fully diagnosed.
Experience has shown that a methodical, whole-system orientated
approach is the most effective for solving problems with gas detection
systems and installations.

Fault / Problem

Output is 0mA

Cause:

Remedy:

Cause:

Remedy:

Cause:

Remedy:

Cause:

Remedy:

Cause / Remedy

Unit is in FAULT condition

Connect SHC-1 interrogator to unit
and use DIAGNOSTIC menu options to
ascertain reason for FAULT report.

Electrical installation problem.

(1) Check +24V power supply to unit.

(2) Check cables and connections,

especially 4-20mA loop connections.

(3) Check that unit has correct 4-20mA

output conguration for use with the

controller.

Optical surfaces are obscured by dirt /
contaminants.

Clean optical surfaces.

Unit’s zero position has negative offset.

Check that optics are clean and dry.
Re-zero unit.

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Fault / Problem

Output is 0mA

Unit fails to
respond to
SHC-1 Handheld
Interrogator

Cause:

Remedy:

Cause:

Remedy:

Cause:

Remedy:

Cause:

Cause / Remedy

Unit has developed an electrical fault.

Most electrical faults result from damage
caused by site / installation problems.
Check for correct wiring, voltage spikes
/ transients, power surges and earthing
problems.

Incorrect connection of interrogator’s
communication link.

Check that the SHC-1 is correctly plugged
into IS socket or that SHC Protection
Device leads are connected to the right
junction box terminals.

Incorrect software version in Handheld
Interrogator.

Optima Plus only works with version 3V0
interrogator software and above. Check
interrogator software version.

No power applied to Optima Plus unit.

Remedy:

Cause:

Remedy:

Cause:

Remedy:

Check +24V power supply to unit.

Incorrect mode selected on interrogator.

Select Optima + mode on interrogator.

Battery failed in Handheld Interrogator.

Check / replace interrogator battery.

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Fault / Problem

Unit does not
respond to test
gas.

Unit does
not produce
the predicted
response to test
gas.

Cause:

Remedy:

Cause:

Remedy:

Cause / Remedy

If unit is sending 4mA (active), this is more

likely to be a problem with the test gas or

gassing technique than with the unit.

(1) Check that the functional gas test

procedure is being performed

correctly. (See Section 7.2)

(2) Check that correct test gas and

concentration are being used.

(3) Check that the gas cylinder is not

empty.

(4) Check that any gas tubing or

inlet pipes used are not broken or
blocked.

(5) Check that the unit is not in FAULT

(0mA) or FORCE’d to a particular

4-20mA output current.

Problem with test gas or gassing

technique.

(1) Check that the functional gas test

procedure is being performed
correctly. See Section 7.2, paying

particular attention to items 15)
to 17). (Also see Section 6.4
CAUTIONS.)

Cause:

Remedy:

(2) Check that the correct test gas and

concentration are being used.

Calibration error or span drift.

If certain that the gas and gassing

technique are correct and that any

discrepancy is due to the unit’s calibration,
re-calibrate the unit in accordance with

Section 6.4.

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Fault / Problem Cause / Remedy

Unit’s output
appears to be
drifting.

Cause:

Remedy:

Cause:

Remedy:

Correct response to genuine, low level

uctuations in gas concentration where

the unit is installed.

A commonly misinterpreted problem
which is resolved when the source of the

uctuating gas leak is nally identied.

If a unit is transmitting a gas reading,
double-check the gas concentration at
the exact point where the detector is
installed using a sensitive portable gas
detector that has been carefully zeroed.

(Do not use a standard catalytic detector

on a 0-100% LEL range, they are not
sensitive enough to reliably detect low %

LEL concentrations.)

Build-up of contaminants on optics,
especially oil-mist, exhaust fumes, grease
and solvents.

Check that dust barrier is tted correctly,

clean and intact. Closely inspect the
optics to be sure that nothing is building
up on them. Clean and re-zero unit if
necessary.

Cause:

Remedy:

Exposure of unit to extreme
temperatures.

Check unit’s FAULT / WARNING log
to see if it has records of Temp Lim
Exceded. If temperature problems are

conrmed, either relocate or shield the

detector or consider use of a sampling
system.

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