Gas Detection

We have a helpful Gas Detection Overview here with a general explanation of gas detection issues.

Being authorised Sensitron distributors we offer a complete range of state-of-the-art gas sensors and panels. Whether it is flammable gases or toxic gases you wish to detect, choosing the right equipment and the right location for mounting sensors is vital. All gas sensors need to be replaced on a regular basis so it is important to consider the long-term economic costs of any gas detection project. We have years of experience in industrial applications and the support of one of Europe's leading gas detection manufacturers

Sensitron are one of Europes's leading gas detection manufacturers. Their website:

The MULTISCAN++ panels are advanced multifunction gas detection control panels designed to meet with the increasing requests for highly flexible intelligent systems. A powerful microprocessor allows a wide range of self-testing facilities to detect and localize possible faults. The system allows the connection of gas detectors and remote input/output modules via 2 closed loops. The control panels can manage and monitor up to 256 gas detectors. These can either be addressable detectors, daisy-chained on the available loops, or analogue type with 4-20mA transmission, connected via remote 8 input cards STG/IN8-S. The system architecture includes 8 preset relays onboard the units and the possibility to have further 256 open collector outputs via remote STG/OUT16-S output cards. To these cards it is possible to connect 8-relays boards, should relay outputs be required.

GALILEO 8/32 are advanced multifunction gas detection control panels designed to control and monitor up to 8 analogue 4-20 mA gas detectors (GALILEO 8) or up to 32 addressable gas detectors (GALILEO 32).On the GALILEO 8/32 front plate, a high brightness LCD provides a real-time monitoring of the concentration being measured; in case of an alarm, the threshold reached and the respective channel are shown.The control panels are housed in metal cabinets, complete with 24 Vdc, 5 A power supply and can hold two back-up batteries max. 12V, 7Ah.

The PL4+ gas control unit represents the best technology for the detection of flammable, toxic or Oxygen compounds in small systems. The PL4+ has 4 analogue 4-20 mA inputs that can be extended to 8 by using the 4-input expansion board PL4/ESP, easy to plug in the control unit. The panel is housed in IP65 ABS box with a 12Vdc 1.5 A power supply integrated. Mode status LEDs for alarms and fault warning along with the backlit LCD display provide for real time gas concentration reading. Alarms are user selectable and for each input it is possible to set the type of detector, its full scale range and the alarm thresholds. The panel can be easily programmed via the three position key-switch for Set, Unset and Program along with the Reset and Acknowledge push buttons. The panel comes complete with 5 output relays: one for each threshold (AL1, AL2, AL3), 1 for fault (FLT) and 1 auxiliary and freely programmable. By using the 4-input expansion board, the panel can have a further 16 Open-Collector outputs linked to the second and third alarm thresholds (AL2 œ AL3) of each detector connected.

Gas Sensors

SMART3G series gas detectors are employed to detect flammable compounds (%LEL), toxic compounds (ppm) and Oxygen content for both depletion and enrichment in classified areas. The Pellistor sensors employed for the flammable detection show an excellent output linearity up to 100% LEL.

For aggressive atmospheres, where the Pellistor sensors would be seriously damaged, Sensitron developed a version employing industrial grade Infrared sensors: IR sensors are poison free and this grants a higher accuracy and a longer lifetime to the cell.

For the toxic gas detection, Sensitron has operated a reliable selection among the most performing electrochemical cells to supply units representing the state of the art in toxic gas detection. SMART3G-C has been specifically designed to offer high performance products for light industrial applications. SMART3G-D have been designed to meet with tougher industrial requirements and offer a 4 digits back-lit display and 5 mode status LEDs for the gas concentration reading. They feature non intrusive magnetic calibration for an accurate and easy calibration via Hall-effect switches, without opening the instrument and declassifying the area.

Specific gas detectors for tunnels and mines are available with certification for Group I.

SMART3G are ATEX certified for Group II 2G, 2GD, 3G & GD and for Group I M2.

The SMART3 NC gas detectors represent a non certified version of the SMART3G line and are ideal for non classified areas and car parks. They employ high quality catalytic sensors, electrochemical cells or infrared sensors, that grant an excellent linearity and accuracy, besides an estimated lifetime of 4 years. The SMART 3NC gas detectors provide a proportional 4-20mA output signal. By employing optional boards they can either communicate on a serial bus RS 485 or provide relay outputs.

The available outputs are as follows:

4-20 mA: Proportional 4-20mA output current corresponding to the full range (LEL or ppm).

Relay. By adding the STS3REL board, the unit is provided with 3 relays with voltage free changeover contacts. One relay is dedicated to the Fault and Watch-dog, while the remaining two relays can be associated to two out of the three available alarm thresholds.

Serial RS485. By adding the STS.IDI interface, the detector can communicate on RS485 bus with SENTOX IDI and MULTISCAN++ gas control panels

The SMART3 NC detectors employ a powerful microprocessor that provides the following built-in features:

Self-diagnostic procedures to control the hardware and sensor correct operation.

Zero follower to maintain the detector zero point, from possible drifts caused by thermal or physical variations of the transducer.

Digital filter, employed in the digital analysis of the analog values sampled, this filter corrects temporary phenomena from causing reading errors or false alarms.

Hysteresis cycle: applied to the outputs associated to the alarm thresholds, it prevents continuous output switching when close to the threshold values.

The SMART3 NC detectors offer a fast and failsafe installation as well as an easy maintenance and calibration routine via the handheld keypad STS/CKD. The SMART3 NC gas detectors run with a power supply at 12-24Vd and are available in IP55 rated enclosure.

The residential gas detectors series "PATROL" have been designed to offer the customers devices representing the highest technology for the detection of Methane, LPG or CO in residential premises. Detection is performed by employing catalytic sensors for Methane and LPG (CATALIX) and electrochemical cells for Carbon Monoxide (CO-DETECT).

The "PATROL" gas detectors for flammable gases offer a double alarm threshold as Pre-alarm and Alarm that generate when the preset alarm thresholds have been reached and can be integrated into fire alarm systems to give a pre-alarm and alarm indication on the fire panel.

A visual (LED) and audible (buzzer) indications warn of the potential dangerous situation while relay activates only in case the Alarm threshold has been exceeded. Whenever either the sensor or any electronic components get damaged, a Fault condition generates, activating the corresponding warnings. The detectors have a WD signaling for the microprocessor control system that activates if faults occur during operation.

Detectors "CATALIX" and "CO-DETECT" have been designed to fully comply with the European Standards for gas detection in residential environment EN 50194 and EN 50291 respectively. As far as "CO-DETECT" is concerned, the European Standards EN50291 requires that relay intervention be temporised as a function to the CO contents reached within a given period of time: the higher is the concentration, the sooner the relay will activate, as described in table 1 on the datasheet.