Crowcon Xgard Bright Manual

Installation, Operation and Maintenance Instructions
M070068
Issue 5
December 2020
Xgard Bright
Gas Detectors with Display and Relays

Contents
1. Introduction.............................................................................. 1
1.1 Product overview.............................................................. 1
1.2 Safety information............................................................ 1
1.3 Storage instructions.......................................................... 2
1.4 Certification labels............................................................ 3
1.5 Product dimensions .......................................................... 4
1.6 Exploded view .................................................................. 5
2. Installation................................................................................ 6
2.1 Location ........................................................................... 6
2.2 Mounting......................................................................... 7
2.3 Internal Electrical Connections.......................................... 7
2.4 General Cabling Requirement .......................................... 8
2.5 Cabling Requirement 4 to 20 mA Current Loop ............... 8
2.6 Cabling Requirement Multidrop MODBUS ........................ 9
2.6.1 Calculating acceptable cable length and detector
quantities............................................................... 10
2.7 Earthing requirements .................................................... 14
2.8 Cable glands .................................................................. 15
2.9 Fitting accessories........................................................... 18
3. Operation ............................................................................... 19
3.1 Operation panel ............................................................. 19
3.2 Key Operation ................................................................ 19
3.3 Start up.......................................................................... 20
3.4 Menu functions.............................................................. 21
3.5 Zero ............................................................................... 22
3.6 Calibrate ....................................................................... 22
3.7 Routine maintenance ..................................................... 23
3.8 Sensor replacement........................................................ 23
4. Specifications.......................................................................... 25
5. Spare parts ............................................................................. 26
6. Warranty ................................................................................ 28

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1. Introduction
1.1 Product overview
Xgard Bright is a versatile gas detector for monitoring a wide range of
flammable and toxic gases and oxygen levels. Xgard Bright incorporates a
bright OLED (organic light emitting diode) display and a magnetic wand for
easy menu operation.
Xgard Bright provides analogue 4-20mA and RS-485 Modbus signals as
standard, with optional HART interface. Relays are also fitted for activating local
alarms or sending digital signals to control systems.
Xgard Bright may be fitted with electrochemical type toxic or oxygen sensors,
pellistor-type flammable gas sensors, molecular property spectrometers (MPS),
or infrared (IR) hydrocarbon or carbon dioxide gas sensors. Please refer to the
product identification label to determine the type of sensor fitted.
Pellistor and MPS sensors are designed to detect flammable gases and vapours
in concentrations not exceeding the Lower Explosive Limit (LEL) of the target gas
for which the detector is calibrated.
Xgard Bright is ATEX and IECEx Ex db IIC T6 Gb flameproof certified for use in
Zone 1 or 2 hazardous gas areas and Ex tb IIIC T80°C Db for use in Zone 21 or
22 hazardous dust areas.
1.2 Safety information
Safety information relevant to Ex requirements:
• WARNING – POTENTIAL ELECTROSTATIC CHARGING HAZARD. The painted
aluminium enclosure constitutes a potential electrostatic hazard and the
equipment must only be cleaned using a damp cloth.
• The cable gland must be installed before use and must comply with the
requirements of standards EN60019-0 and EN60079-1 with minimum IP66
ingress protection.
• Unused cable entries must be sealed using an ATEX/IECEx Exd certified
stopping plug with minimum IP66 ingress protection.
• Only cables of types specific in these instructions can be used.
• External earthing should be considered and installed according to these
instructions before use.
• WARNING – DO NOT OPEN WHEN AN EXPLOSIVE ATMOSPHERE IS
PRESENT.

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• The lid on Xgard Bright must be kept tightly closed until power to the
detector is isolated otherwise ignition of a flammable atmosphere can
occur. Before removing the cover for maintenance, ensure the surrounding
atmosphere is free of flammable gases or vapours.
General safety information
• Xgard Bright gas detectors must be installed, operated and maintained in
strict accordance with these instructions, warnings, label information, and
within the limitations stated.
• Xgard Bright detectors are designed to detect gases or vapours in air, and
not inert or oxygen deficient atmospheres. Xgard Bright oxygen detectors
can measure in oxygen deficient atmospheres. Please note: the exception
is for IR versions of Xgard Bright which do not require the presence of
oxygen to function. IRCO2 and IR flammable gas Xgard Bright works
perfectly well in inert atmospheres.
• Electrochemical cells used in toxic and oxygen versions of Xgard Bright
contain small volumes of corrosive electrolyte. Care should be observed
when replacing cells to ensure that the electrolyte does not come into
contact with skin or eyes.
• Maintenance and calibration operations must only be performed by
qualified service personnel.
• Only genuine Crowcon replacement parts must be used, substitute
components may invalidate the certification and warranty of the detector.
• Xgard Bright detectors must be protected from extreme vibration, and
direct sunlight in hot environments as this may cause the temperature of
the detector to rise above its specified limits and cause premature failure. A
sunshade is available for Xgard Bright.
Note: If the sinter is subjected to direct water jet the product must be
bump tested with gas to ensure correct operation.
• This equipment must not be used in a Carbon Disulphide atmosphere.
1.3 Storage instructions
Some types of sensor available with Xgard Bright have limited life when left
un-powered and/or may be adversely affected by temperature extremes or
environmental contamination. Ideal storage conditions are 20˚C and 60%RH.
Do not expose sensors to contaminants such as silicones, lead compounds and
strong solvents such as isopropanol. It is strongly recommended detectors are
installed and powered within 3 months of purchase.

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1.4 Certification labels
Diagram 1: Xgard Bright Certification Labels
ATEX and IECEx certification label
Gas name and range label
Warning label

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1.5 Product dimensions
All dimensions in millimetres
Diagram 2: Xgard Bright dimension view

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1.6 Exploded view
Diagram 3: Xgard Bright exploded view

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2. Installation
WARNING
This detector is designed for use in Zone 1 and Zone 2 or Zone 21
and Zone 22 hazardous areas, and is certified Ex db IIC T6 Gb and Ex
tb IIIC T80°C Db for operation up to 70°C (158°F). Installation must
be in accordance with the recognized standards of the appropriate
authority in the country concerned. For further information please
contact Crowcon. Prior to carrying out any installation work ensure
local regulations and site procedures are followed.
2.1 Location
The detector should be mounted where the gas to be detected is most likely to
be present. The following points should be noted when locating gas detectors:
• To detect gases which are lighter than air, detectors should be mounted at
high level and Crowcon recommend the use of a collector cone (Part No.
C01051).
• To detect heavier than air gases, detectors should be mounted at low level.
• When locating detectors consider the possible damage caused by natural
events e.g. rain or flooding. For detectors mounted outdoors Crowcon
recommend the use of a Spray Deflector (Part No. C01052).
• Consider ease of access for functional testing and servicing.
• Consider how the escaping gas may behave due to natural or forced air
currents. Mount detectors in ventilation ducts if appropriate.
• Consider the process conditions. For example, butane is normally heavier
than air, but if released from a process which is at an elevated temperature
and/or pressure, the gas may rise rather than fall.
• Location of oxygen sensors requires knowledge of the gas that may
displace the oxygen. For example, carbon dioxide is denser than air and
therefore is likely to displace oxygen from low levels upwards.
• Sensors should be mounted at head height (1.5m nominally) to detect
gases of a similar density to air, assuming that ambient conditions and the
temperature of the target gas are nominally 20˚C.
The placement of sensors should be determined following advice of experts
having specialist knowledge of gas dispersion, the plant processing equipment
as well as safety and engineering issues. The agreement reached on the
locations of sensors should be recorded.