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Protec II Toxic Gas Detection System

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About the Product

Toxic Gas Detection System

The Protec II (SAS) is a “Stand Alone” remote sensing system for toxic gases. it is intended to be placed in the area where leaks of these potentially dangerous gases are likely to occur. The protec II sensors measures the levels of these gases, activates alarms based on the concentration, and can transmit a signal to the appropriate control device.

An electrochemical toxic sensor provides fast, accurate and specific responses to the gas of concern. The gas concentration is continuously indicated by an LCD Digital Display which is visible through the window of the enclosure. Two on-board failsafe alarms trip, when the user selected gas concentrations are exceeded. The alarms can be used to activate relays, lights, horns, or other devices which provide a warning or remedy the situation. The electronics converts the sensor signal into an optional RS-232 signal for transmission to the controller, a distributed control system (DCS), programmable logic controller (PLC) or other types of centralized control stations.

Protec II® Electronics

The Protec II electronics are designed to reduce the concerns and expenses of installation, operation, and maintenance. Alarm level indicators are visible through the display window.

Internal diagnostics continually review operation of the electronics and sensor. Should a fault be detected in any operation of the sensing head, a Fail indication and fault alarm are activated. This provides safe operation of the Protec II sensing head.

The SAS is designed to operate at under 10 mW power consumption in safe operation to provide a long operating life from batteries with toxic sensors or an indefinite lifetime when solar charged. This capability alone makes the system extremely attractive for remote and isolated areas. With the integral fail-safe alarms and the optional RS-232 signals, several configurations are possible for additional status indications and reactions that are user configurable. This also allows the user to custom define and configure the system to your requirements.

Sensor Technology

The high-performance electrochemical sensor for toxic gases provides long, reliable operation over a wide range of environmental, and application demands. The patented sensor technology can accurately detect most toxic gases and is not adversely affected by high concentrations. The three-electrode design maximizes the response to toxic gases while minimizing the effects of other gases. This reduces the amount of false alarms experienced when other gases are present.

A special feature of this unit’s electrochemical sensors is an internal temperature compensation circuit. A thermistor is placed near the sensor which minimizes signal drift due to changing ambient temperature conditions.

A catalytic oxidation sensor (pellistor) is used to detect a wide variety of combustible gases and vapours like methane, ethane, hydrogen, etc. The combustible gas sensor design minimizes the adverse effects of sulfur, silicon, halogen, and heavy-metal bearing compounds thus providing long and more reliable operation.

Remote Toxic Gas Detectors


  • Low power operation, only 10 mW and no external power needed
  • Patented sensor technology provides fast, accurate and specific responses to many toxic gases
  • Detects a wide range of toxic gases and vapours
  • Built-in Warning, Alarm and Fault Relays allow stand-alone operation
  • One-man calibration and alarm adjustments
  • Digital display of gas concentrations
  • Sensor can be placed remotely from the controller up to 10,000 feet away
  • Compatible with data acquisition systems which accept a 4-20 mA or 0-1v signal