FAQs

This fault means XD ONE has detected an electronic failure of the internal memory.

The device alerts the user and enters an error state. Contact Trolex or an approved distributor.

This fault means XD ONE has detected an electronic hardware failure of the particulate sensor.

The device alerts the user and enters an error state. Contact Trolex or an approved distributor.

This fault means corruption was detected in the XD ONE settings.

The device automatically reverts to factory defaults and continues operation, so check and reapply required configuration in BreatheLITE.

A particulate sensor data error means corrupt data was received from the particulate sensor. XD ONE ignores the reading, logs the event, and continues operation.

If this occurs more than four times, the device alerts the user and enters an error state. Contact Trolex or an approved distributor.

If XD ONE internal memory is full, download and clear XD ONE data, event logs, and alarm logs.

Confirm important data has been downloaded before clearing stored records.

Internal memory corruption means corruption has been detected and data loss has occurred or readings cannot be recovered.

The device automatically formats its memory and continues operation.

For a non-recoverable fatal error, XD ONE stops normal operation and alerts the user with flashing red LEDs and an audible sequence.

The manual recommends contacting the Trolex service team for support.

In a recoverable operating error, XD ONE logs the event and automatically takes appropriate action to resolve it.

After recovery, check previous data capture and device settings before continued operation. User configuration may need to be redefined in BreatheLITE.

Connect XD ONE to the BreatheLITE application. Captured particulate data can be downloaded, reviewed, and analysed through the BreatheLITE data analysis tool set.

The manual also notes that Live readout mode streams live particulate data while data is logged to internal memory.

Connect XD ONE to BreatheLITE. Users can configure device name, COM port, operating mode, alarm PM size, TWA period and threshold, STEL period and threshold, log rate, and particle density.

Use the BreatheLITE in-application help for detailed setup guidance.

Press, hold, and release the power button after two seconds. The device confirms acknowledgement with an LED sequence.

Acknowledgement silences the audio alarm while the LED remains solid if the alarm condition is still present. The alarm resets only when levels fall below 95% of the alarm setpoint.

XD ONE uses two LED icons and audio sequences. The STEL alarm flashes the amber icon with two beeps per second, while the TWA alarm flashes the red icon with three beeps per second.

If both alarms are triggered at the same time, the TWA alarm takes priority.

Data-log mode captures readings like Normal mode, but does not check them against alarm thresholds and does not trigger on-device warnings.

It is intended for passive monitoring where data is downloaded later and analysed in BreatheLITE.

In-cab mode allows the particulate sensor and device warnings to remain active while XD ONE is connected or powered via USB, supporting continuous vehicle use.

The device turns itself off five minutes after USB power is removed to save power.

XD ONE provides Normal, In-cab, Data-log, and Live readout modes.

Normal mode records data and checks alarm thresholds; In-cab keeps sensing active while powered via USB; Data-log records without triggering warnings; Live readout streams live particulate data to BreatheLITE while also logging data.

XD ONE initiates automatic low-power shutdown and runs the power-off sequence. If the device is powered on without sufficient charge, it immediately runs the shutdown sequence again.

Charge the device before attempting to restart monitoring.

XD ONE charges through the on-device USB port and supplied cable. The manual recommends using the supplied wall adapter where possible so the maximum power is delivered in the shortest timeframe.

Charging from a PC USB port is possible but takes significantly longer due to standard PC USB power delivery limitations.

A green flashing battery icon indicates 100% to 70% charge, amber indicates 69% to 40%, and red indicates 39% or lower.

When battery charge falls below 10%, the red warning flashes every second. At 0%, automatic low-power shutdown starts.

If XD ONE returns a fail result, it checks whether the fault is recoverable and repeats the self-test up to four times.

If a fatal error indication remains, the manual recommends contacting the Trolex service team.

During normal operation, press and hold the power button until all three function icons are blue, then release the button.

The device initiates the self-test sequence and displays a pass or fail result through the audible and visual alarm sequence.

XD ONE self-test checks OPC sensor communications, internal electronic hardware, battery pack function and calibration, data logging communications, and EEPROM memory.

Green flashing icons indicate a pass result, while red flashing icons indicate a failure or identified error.

Press and hold the front function button to start the power-off sequence, then release it when all icons illuminate white.

The icons illuminate incrementally before XD ONE powers down.

XD ONE begins particulate sampling automatically once the power-on and startup routine is complete.

STEL and TWA calculations, alarm warnings, and data recording are active alongside particulate sampling after startup.

Fully charge XD ONE before first power on. Press and hold the front function button, then release it when all icons illuminate white.

The device starts up, performs self-test, displays a pass or fail result, and then automatically begins sampling particulate concentrations.

XD ONE is supplied with an alligator mounting clip as standard. A Klick Fast stud is available for wearable, wall, and pole fixing kits.

The device also includes four M3 threaded mounting holes for custom mounting, and the manual describes a stability bracket, strap, pole mount, wall, body, and in-cab mounting options.

XD ONE defaults include operating mode Normal, alarm PM size PM4.25, TWA period 8 hours, TWA threshold 1000 µg/m³, STEL period 15 minutes, STEL threshold 1000 µg/m³, log rate 10 seconds, and particle density 1.65 g/ml.

Default settings can be manually changed with Trolex BreatheLITE.

XD ONE can be configured to measure and warn users based on PM1.0, PM2.5, PM4.25, and PM10, and it can report Total Suspended Particulates.

The manual describes recording particulates between 0.35 µm and 40 µm.

Confirm the inlet or top cap is open where applicable, check that entry and exit apertures are not blocked, verify the selected operating mode, check the configured PM channel or RCS averaging period, and confirm that the device has completed its startup or self-test routine.

For fixed instruments, also check power and communications. For portable devices, check battery level and whether the sensor is active in the selected mode.

Check for local dust events, atomised spray or mist, the device position relative to the source, blocked or contaminated flow paths, recent maintenance status, particle type, airflow patterns, and whether the configured PM size, density, averaging period, or alarm channel matches the intended application.

If the reading is accompanied by a fault, follow the fault-code guidance for the product.

Each monitor must be operated within the temperature, humidity, ingress protection, and use limits in its technical section. The manuals warn that operating outside those limits may damage equipment or prevent the product achieving its performance specification.

Operation at temperature extremes for extended periods can reduce product operating lifetime.

The monitors rely on an unobstructed particle flow path. If the inlet, top cap, outlet, grille, or exit aperture is blocked, particulate sensing airflow can be reduced or prevented.

Blocked airflow can lead to unexpected readings, fault conditions, failed checks, or loss of monitoring function depending on product and severity.

A fail result means the device did not meet the response threshold used by the compliance check. The manuals instruct users to clean the sensor or dust path, repeat the check, and note the result.

If the device repeatedly fails, contact Trolex or an approved service route for support.

A pass result means the particulate sensor is functioning as expected against the compliance check routine and normal monitoring operation can resume.

The result should still be considered part of the product maintenance record rather than a replacement for any required site procedure.

The manuals recommend periodic cleaning with a damp cloth so that displays, keypads, membranes, rating labels, and product labels remain clean and legible.

Do not use this as a substitute for the product-specific sensor or dust-path cleaning procedure where one is required.

Routine visual checks should look for external damage, cracked or broken plastic parts, damage to wiring or USB cables where applicable, damaged membranes or buttons, blocked particulate entry or exit apertures, damaged mounting hardware, and missing, peeling, or discoloured labels.

The exact checklist varies by product, but the maintenance sections consistently link these checks to IP rating, airflow, legibility, and safe operation.

The XD1+ and XD ONE manuals describe 3-monthly compliance checks using the Trolex Compliance Pack+ and BreatheLITE automated test routine.

The check uses reference material dosed into the particulate dispersion hood while the device is positioned in the compliance base.

Run the sensor cleaning procedure described for the product, then repeat the compliance audit check and record the result. If the repeated test passes, normal monitoring can resume.

If the device returns a repeated fail result, the manuals instruct users to contact Trolex or an approved support/service route to discuss servicing options.

A compliance audit check is an instrument function used to check device response against reference particulate material. The manuals describe use of a particulate dispersion hood or compliance base, reference particle sizes, and a dosing bottle.

A pass result indicates that the particulate sensor is functioning as expected. A fail result should be followed by the cleaning and repeat-test steps in the relevant manual.

Particulate readings depend on particles passing through the sensing flow path. The manuals warn that blocked inlets, blocked exits, clogged grilles, or obstructed apertures can obscure the sensing airflow and affect device function.

Install, wear, or mount the product so that the entry and exit apertures remain clear, and include aperture checks in routine maintenance.

The manuals note that the position of a device relative to the target sample can affect the observed measurement. Particle saturation, local airflow, dust type, device configuration, drift over time, maintenance condition, and heavy dust exposure can all contribute to differences between nearby devices.

For this reason, readings should be interpreted with awareness of the local environment and the way the instrument is installed or worn.

Particulate matter, or PM, is the general term used for solids and liquid droplets suspended in air. The manuals describe PM as material that may come from combustion, industrial activity, natural sources, or working processes.

Trolex particulate monitors report selected PM size fractions so changes in airborne particulate levels can be viewed, logged, alarmed, or analysed depending on the product.

This fault means XD1+ has detected an electronic failure of the internal memory.

The device alerts the user and enters an error state. Contact Trolex or an approved distributor.

This fault means XD1+ has detected an electronic hardware failure of the particulate sensor.

The device alerts the user and enters an error state. Contact Trolex or an approved distributor.

This fault means corruption was detected in the XD1+ settings.

The device automatically reverts to factory defaults and continues operation, so custom configuration should be checked and reapplied in BreatheLITE as needed.

A particulate sensor data error means data received from the particulate sensor was corrupt. XD1+ ignores the reading, logs the event, and continues operation.

If this occurs more than four times, XD1+ alerts the user and enters an error state. Contact Trolex or an approved distributor.

If XD1+ internal memory is full, download and clear XD1+ data, event logs, and alarm logs.

Confirm that required records have been downloaded before clearing stored data.

Internal memory corruption means data loss has occurred or readings cannot be recovered.

The manual states that XD1+ will automatically format its memory and continue operation.

For a non-recoverable fatal error, XD1+ stops normal operation and alerts the user with flashing red LEDs and an audible sequence.

The manual recommends contacting the Trolex service team for support.

In a recoverable operating error, XD1+ logs the event and automatically takes action to resolve it.

After notification of recovery, check previous data capture and device settings before continuing. User settings may need to be redefined in BreatheLITE.

When Trolex releases updated operating firmware and instructions, connect XD1+ to BreatheLITE to perform the local update.

Trolex provides notification, release notes, and update instructions for the latest firmware.

Connect XD1+ to the BreatheLITE application. The device is designed to collect particulate data during operation for download, review, and analysis through the BreatheLITE data analysis tools.

The multiway data and charging dock can connect up to five XD1+ devices for charging and data collection.

Connect XD1+ to BreatheLITE. The software allows configuration of device name, COM port, operating mode, alarm PM size, TWA period and threshold, STEL period and threshold, log rate, and particle density.

Use the BreatheLITE in-application help for detailed configuration steps.

Press, hold, and release the power button after two seconds. XD1+ confirms acknowledgement with an LED sequence.

Acknowledgement silences the audio alarm, but the LED remains solid while the alarm condition is still present. The alarm resets only when particulate levels fall below 95% of the alarm setpoint.

XD1+ uses two LED icons and audio sequences. The STEL alarm flashes the amber icon with two beeps per second. The TWA alarm flashes the red icon with three beeps per second.

If both alarms trigger at the same time, the TWA alarm takes priority.

In-cab mode keeps the particulate sensor and device warnings active while XD1+ is connected or powered via USB, allowing continuous use in a vehicle.

The device turns itself off five minutes after USB power is removed to save power.

Data-log mode follows Normal mode data capture behaviour, but readings are not checked against alarm thresholds and on-device warnings do not trigger.

It is intended for passive monitoring where data is downloaded and analysed later in BreatheLITE.

XD1+ has four selectable operating modes: Normal, In-cab, Data-log, and Live readout.

Normal mode captures data and checks alarms; In-cab keeps sensing and warnings active while powered via USB; Data-log records without warning alarms; Live readout streams live particulate data to BreatheLITE via USB.

The battery health is continuously monitored during operation and is calibrated when the battery is fully charged.

If the battery is fully depleted, XD1+ loses the current stored battery calibration data. Fully charging the device recalibrates battery monitoring.

XD1+ initiates automatic low-power shutdown and runs the power-off sequence. If the user attempts to power the device on without enough charge, it immediately runs the shutdown sequence again.

Fully charge the device before restarting monitoring.

A green flashing battery icon indicates 100% to 70% charge. Amber indicates 69% to 40%. Red indicates 39% to 10%.

Below 10%, the red warning flashes every second. At 0%, XD1+ initiates automatic low-power shutdown.

If the self-test returns a fail result, XD1+ checks whether the fault is recoverable and repeats the self-test up to four times.

If the fault becomes a fatal error indication, the manual recommends contacting the Trolex service team.

During normal operation, press and hold the power/function button until all three function icons are blue, then release the button.

XD1+ runs the self-test sequence and displays the pass or fail result through the audible and visual indication sequence.

The XD1+ startup self-test checks OPC sensor communications, internal electronic hardware, battery function and calibration, data logging communications, and EEPROM memory so custom user settings are not lost.

A pass is shown with green flashing icons. A fail is shown with red flashing icons.

Press and hold the function button to initiate the power-off sequence, then release the button when all icons illuminate white.

The icons illuminate incrementally before the device powers down.

XD1+ begins particulate sampling as soon as the power-on and startup routine is complete.

STEL and TWA calculations, alarm warnings, and data recording become active alongside particulate sampling following the power-on sequence.

Before first power on, fully charge XD1+ using the supplied charger. Press and hold the function button, then release it when all icons illuminate white.

The device runs a startup routine, performs self-test, displays a pass or fail result, and then automatically begins particulate sampling.

XD1+ defaults include operating mode Normal, alarm PM size PM4.25, TWA period 8 hours, TWA threshold 1000 µg/m³, STEL period 15 minutes, STEL threshold 1000 µg/m³, log rate 10 seconds, and particle density 1.65 g/ml.

Default settings can be changed using Trolex BreatheLITE and BreatheMOBILE.

XD1+ supports PM1.0, PM2.5, PM4.25, and PM10 measurement ranges, with a particle sizing range of 0.1 µm to 10 µm.

The device alarms against a selected PM value but logs multiple PM sizes for offline review.

Confirm the inlet or top cap is open where applicable, check that entry and exit apertures are not blocked, verify the selected operating mode, check the configured PM channel or RCS averaging period, and confirm that the device has completed its startup or self-test routine.

For fixed instruments, also check power and communications. For portable devices, check battery level and whether the sensor is active in the selected mode.

Check for local dust events, atomised spray or mist, the device position relative to the source, blocked or contaminated flow paths, recent maintenance status, particle type, airflow patterns, and whether the configured PM size, density, averaging period, or alarm channel matches the intended application.

If the reading is accompanied by a fault, follow the fault-code guidance for the product.

Each monitor must be operated within the temperature, humidity, ingress protection, and use limits in its technical section. The manuals warn that operating outside those limits may damage equipment or prevent the product achieving its performance specification.

Operation at temperature extremes for extended periods can reduce product operating lifetime.

The monitors rely on an unobstructed particle flow path. If the inlet, top cap, outlet, grille, or exit aperture is blocked, particulate sensing airflow can be reduced or prevented.

Blocked airflow can lead to unexpected readings, fault conditions, failed checks, or loss of monitoring function depending on product and severity.

A fail result means the device did not meet the response threshold used by the compliance check. The manuals instruct users to clean the sensor or dust path, repeat the check, and note the result.

If the device repeatedly fails, contact Trolex or an approved service route for support.

A pass result means the particulate sensor is functioning as expected against the compliance check routine and normal monitoring operation can resume.

The result should still be considered part of the product maintenance record rather than a replacement for any required site procedure.

The manuals recommend periodic cleaning with a damp cloth so that displays, keypads, membranes, rating labels, and product labels remain clean and legible.

Do not use this as a substitute for the product-specific sensor or dust-path cleaning procedure where one is required.

Routine visual checks should look for external damage, cracked or broken plastic parts, damage to wiring or USB cables where applicable, damaged membranes or buttons, blocked particulate entry or exit apertures, damaged mounting hardware, and missing, peeling, or discoloured labels.

The exact checklist varies by product, but the maintenance sections consistently link these checks to IP rating, airflow, legibility, and safe operation.

The XD1+ and XD ONE manuals describe 3-monthly compliance checks using the Trolex Compliance Pack+ and BreatheLITE automated test routine.

The check uses reference material dosed into the particulate dispersion hood while the device is positioned in the compliance base.

Run the sensor cleaning procedure described for the product, then repeat the compliance audit check and record the result. If the repeated test passes, normal monitoring can resume.

If the device returns a repeated fail result, the manuals instruct users to contact Trolex or an approved support/service route to discuss servicing options.

A compliance audit check is an instrument function used to check device response against reference particulate material. The manuals describe use of a particulate dispersion hood or compliance base, reference particle sizes, and a dosing bottle.

A pass result indicates that the particulate sensor is functioning as expected. A fail result should be followed by the cleaning and repeat-test steps in the relevant manual.

Particulate readings depend on particles passing through the sensing flow path. The manuals warn that blocked inlets, blocked exits, clogged grilles, or obstructed apertures can obscure the sensing airflow and affect device function.

Install, wear, or mount the product so that the entry and exit apertures remain clear, and include aperture checks in routine maintenance.

The manuals note that the position of a device relative to the target sample can affect the observed measurement. Particle saturation, local airflow, dust type, device configuration, drift over time, maintenance condition, and heavy dust exposure can all contribute to differences between nearby devices.

For this reason, readings should be interpreted with awareness of the local environment and the way the instrument is installed or worn.

Particulate matter, or PM, is the general term used for solids and liquid droplets suspended in air. The manuals describe PM as material that may come from combustion, industrial activity, natural sources, or working processes.

Trolex particulate monitors report selected PM size fractions so changes in airborne particulate levels can be viewed, logged, alarmed, or analysed depending on the product.

Confirm the inlet or top cap is open where applicable, check that entry and exit apertures are not blocked, verify the selected operating mode, check the configured PM channel or RCS averaging period, and confirm that the device has completed its startup or self-test routine.

For fixed instruments, also check power and communications. For portable devices, check battery level and whether the sensor is active in the selected mode.

Check for local dust events, atomised spray or mist, the device position relative to the source, blocked or contaminated flow paths, recent maintenance status, particle type, airflow patterns, and whether the configured PM size, density, averaging period, or alarm channel matches the intended application.

If the reading is accompanied by a fault, follow the fault-code guidance for the product.

Each monitor must be operated within the temperature, humidity, ingress protection, and use limits in its technical section. The manuals warn that operating outside those limits may damage equipment or prevent the product achieving its performance specification.

Operation at temperature extremes for extended periods can reduce product operating lifetime.

The monitors rely on an unobstructed particle flow path. If the inlet, top cap, outlet, grille, or exit aperture is blocked, particulate sensing airflow can be reduced or prevented.

Blocked airflow can lead to unexpected readings, fault conditions, failed checks, or loss of monitoring function depending on product and severity.

A fail result means the device did not meet the response threshold used by the compliance check. The manuals instruct users to clean the sensor or dust path, repeat the check, and note the result.

If the device repeatedly fails, contact Trolex or an approved service route for support.

A pass result means the particulate sensor is functioning as expected against the compliance check routine and normal monitoring operation can resume.

The result should still be considered part of the product maintenance record rather than a replacement for any required site procedure.

The manuals recommend periodic cleaning with a damp cloth so that displays, keypads, membranes, rating labels, and product labels remain clean and legible.

Do not use this as a substitute for the product-specific sensor or dust-path cleaning procedure where one is required.

Routine visual checks should look for external damage, cracked or broken plastic parts, damage to wiring or USB cables where applicable, damaged membranes or buttons, blocked particulate entry or exit apertures, damaged mounting hardware, and missing, peeling, or discoloured labels.

The exact checklist varies by product, but the maintenance sections consistently link these checks to IP rating, airflow, legibility, and safe operation.

Run the sensor cleaning procedure described for the product, then repeat the compliance audit check and record the result. If the repeated test passes, normal monitoring can resume.

If the device returns a repeated fail result, the manuals instruct users to contact Trolex or an approved support/service route to discuss servicing options.

A compliance audit check is an instrument function used to check device response against reference particulate material. The manuals describe use of a particulate dispersion hood or compliance base, reference particle sizes, and a dosing bottle.

A pass result indicates that the particulate sensor is functioning as expected. A fail result should be followed by the cleaning and repeat-test steps in the relevant manual.

Particulate readings depend on particles passing through the sensing flow path. The manuals warn that blocked inlets, blocked exits, clogged grilles, or obstructed apertures can obscure the sensing airflow and affect device function.

Install, wear, or mount the product so that the entry and exit apertures remain clear, and include aperture checks in routine maintenance.

The manuals note that the position of a device relative to the target sample can affect the observed measurement. Particle saturation, local airflow, dust type, device configuration, drift over time, maintenance condition, and heavy dust exposure can all contribute to differences between nearby devices.

For this reason, readings should be interpreted with awareness of the local environment and the way the instrument is installed or worn.

Particulate matter, or PM, is the general term used for solids and liquid droplets suspended in air. The manuals describe PM as material that may come from combustion, industrial activity, natural sources, or working processes.

Trolex particulate monitors report selected PM size fractions so changes in airborne particulate levels can be viewed, logged, alarmed, or analysed depending on the product.

Confirm the inlet or top cap is open where applicable, check that entry and exit apertures are not blocked, verify the selected operating mode, check the configured PM channel or RCS averaging period, and confirm that the device has completed its startup or self-test routine.

For fixed instruments, also check power and communications. For portable devices, check battery level and whether the sensor is active in the selected mode.

Check for local dust events, atomised spray or mist, the device position relative to the source, blocked or contaminated flow paths, recent maintenance status, particle type, airflow patterns, and whether the configured PM size, density, averaging period, or alarm channel matches the intended application.

If the reading is accompanied by a fault, follow the fault-code guidance for the product.

Each monitor must be operated within the temperature, humidity, ingress protection, and use limits in its technical section. The manuals warn that operating outside those limits may damage equipment or prevent the product achieving its performance specification.

Operation at temperature extremes for extended periods can reduce product operating lifetime.

The monitors rely on an unobstructed particle flow path. If the inlet, top cap, outlet, grille, or exit aperture is blocked, particulate sensing airflow can be reduced or prevented.

Blocked airflow can lead to unexpected readings, fault conditions, failed checks, or loss of monitoring function depending on product and severity.

A fail result means the device did not meet the response threshold used by the compliance check. The manuals instruct users to clean the sensor or dust path, repeat the check, and note the result.

If the device repeatedly fails, contact Trolex or an approved service route for support.

A pass result means the particulate sensor is functioning as expected against the compliance check routine and normal monitoring operation can resume.

The result should still be considered part of the product maintenance record rather than a replacement for any required site procedure.

The manuals recommend periodic cleaning with a damp cloth so that displays, keypads, membranes, rating labels, and product labels remain clean and legible.

Do not use this as a substitute for the product-specific sensor or dust-path cleaning procedure where one is required.

Routine visual checks should look for external damage, cracked or broken plastic parts, damage to wiring or USB cables where applicable, damaged membranes or buttons, blocked particulate entry or exit apertures, damaged mounting hardware, and missing, peeling, or discoloured labels.

The exact checklist varies by product, but the maintenance sections consistently link these checks to IP rating, airflow, legibility, and safe operation.

Run the sensor cleaning procedure described for the product, then repeat the compliance audit check and record the result. If the repeated test passes, normal monitoring can resume.

If the device returns a repeated fail result, the manuals instruct users to contact Trolex or an approved support/service route to discuss servicing options.

A compliance audit check is an instrument function used to check device response against reference particulate material. The manuals describe use of a particulate dispersion hood or compliance base, reference particle sizes, and a dosing bottle.

A pass result indicates that the particulate sensor is functioning as expected. A fail result should be followed by the cleaning and repeat-test steps in the relevant manual.

Particulate readings depend on particles passing through the sensing flow path. The manuals warn that blocked inlets, blocked exits, clogged grilles, or obstructed apertures can obscure the sensing airflow and affect device function.

Install, wear, or mount the product so that the entry and exit apertures remain clear, and include aperture checks in routine maintenance.

The manuals note that the position of a device relative to the target sample can affect the observed measurement. Particle saturation, local airflow, dust type, device configuration, drift over time, maintenance condition, and heavy dust exposure can all contribute to differences between nearby devices.

For this reason, readings should be interpreted with awareness of the local environment and the way the instrument is installed or worn.

Particulate matter, or PM, is the general term used for solids and liquid droplets suspended in air. The manuals describe PM as material that may come from combustion, industrial activity, natural sources, or working processes.

Trolex particulate monitors report selected PM size fractions so changes in airborne particulate levels can be viewed, logged, alarmed, or analysed depending on the product.

Confirm the correct zero gas and calibration gas are being used for the fitted gBloc, that the gas flow regulator is set to 0.5 L/min to 1 L/min, and that the gas reading has stabilised before adjustment.

Remember that all gas sources have error tolerances and calibration must be performed by competent accredited personnel.

Confirm that the A/V Alarm is fitted and that the LED beacon and sounder are assigned to the relevant Warning, Alarm, Fault, or Over-range functions.

Default settings enable the sounder and beacon for Alarm, Over-range, and Fault, but Warning is off by default.

Confirm the relay card is fitted in an allowed slot, the relay assignment is configured for the intended setpoint, fault, or over-range signal, and the external circuit is an approved intrinsically safe circuit.

The relay contacts have a maximum contact voltage of 16 V DC and maximum switching current of 250 mA.

Check whether Ethernet is configured for Dynamic or Static addressing. Dynamic requires a DHCP server to provide IP information.

If Static is used, confirm the IP address, subnet mask, and gateway settings match the network design and that the Ethernet Card is installed in the correct slot.

The analogue output characteristics table lists maintenance and warmup state at 3.1 mA or 0.31 V.

Fault output is listed separately, and normal operating range is between 0% and 100% full scale.

Normal atmosphere contains carbon dioxide, which affects the CO2 sensor signal.

The manual states that nitrogen must be used to accurately calibrate CO2 zero values and the display value should be stable before commencing sensor zero.

The manual states that the natural level of oxygen available in the atmosphere is influenced by relative humidity and temperature, and the oxygen sensor reacts to these changes.

High carbon dioxide levels over 5% may also have a minor effect on oxygen sensor accuracy.

Nitric oxide sensors must be continuously powered to maintain calibration stability.

If power has been absent for more than 10 minutes, it may take 24 to 28 hours for the sensor to restore stability. Do not calibrate until the output signal is steady.

The manual notes that electrochemical cells can be affected by interfering gases, sudden atmospheric pressure changes, and long periods of very low or high humidity.

In severe pressure-change cases, temporary instability may exceed 60 seconds.

Catalytic combustion sensors rely on oxygen in the atmosphere and can be affected if air is displaced or diluted. Steam-laden atmospheres and condensation can also reduce sensitivity.

Exposure to flammable gas above the LEL can affect sensitivity and zero stability, and calibration should be checked after such exposure.

Pellistor Protect is deployed when measured gas values exceed 100% of full scale on a pellistor sensor.

The display shows Pellistor Lockout alarm, the analogue output is clamped at 22 mA or 2.2 V, MODBUS gas value reads -10,000 with the over-range flag set, and assigned relays or A/V alarms activate.

Release the four outer M4 screws, remove the gas inlet cover, remove the gBloc and cover plate to reveal the terminals, then connect the required terminals using the M16 cable gland.

Replace the cover plate, insert the gBloc, replace the gas inlet cover, and tighten the four M4 screws to 0.7 Nm.

Drift mute is automatic suppression of gas values that have drifted below zero. It can be enabled or disabled as required.

The manual states that Drift mute does not affect under-range alarms or faults.

No. The manual states that sensor coverage cannot be simply expressed as number per unit area.

Sensors need to be sited where they can monitor parts of the plant where gas may accumulate or where a release is expected, so that early warning can initiate shutdown, alarm, or evacuation functions.

Pellistor gBlocs detect flammable methane gas using catalytic combustion sensor technology. The manual states that catalytic sensors rely on oxygen being present in the atmosphere and should only be used for gas concentration up to the lower explosive limit.

Pellistor gBlocs include automatic protection against excessive gas exposure through Pellistor Protect.

Infrared gBlocs monitor carbon dioxide or methane. The manual describes the infrared sensor as highly specific to the selected gas, with consistent sensing accuracy and superior long-term stability.

Normal atmosphere contains carbon dioxide, so nitrogen must be used to accurately calibrate CO2 zero values.

Electrochemical gBlocs monitor toxic gases or oxygen. The manual notes that electrochemical toxic gas cells can be affected by interfering gases, steam-laden atmospheres, condensation, pressure changes, and long periods at very low or high humidity.

These conditions can affect sensitivity, stability, response, or operating life depending on the gas cell.

Each gBloc is programmed with default Gas ID parameters for the gas type. These include gas type, measurement range, serial number, setpoint enable states, setpoint levels, and STEL/TWA setpoint data where applicable.

Pre-programmed alarm setpoints can also contain functional characteristics such as activate over setpoint, activate under setpoint, and hysteresis.