General Monitors-Gas and Flame Detection

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New Combustible Gas Detector with HART® Communication

S4000CH Combustible Gas Detector with HARTThe challenge of installing and maintaining industrial safety devices has compounded over the years as ever fewer workers are tasked with the upkeep of instrumentation. Commissioning and simple maintenance tasks like periodic gas checks and calibration of gas detectors can spell several hours in the field. Recordkeeping, as required by corporate quality procedures, the FDA, and OSHA also contribute to the burden of instrument care, a process which performed by hand can be time consuming and susceptible to human error. With the twin demands for greater productivity and improved safety, it is not surprising that plants have responded by increasing their investment in automation and use of instrument information.

HART, a two way digital communication protocol, has capitalized on this trend. It was designed for use with intelligent measurement and control instruments which traditionally communicate using the 4 – 20 mA analog signal. HART enables digital communication without compromising the integrity of the analog output signal. This makes it an ideal communication protocol for legacy installations, since it requires no additional wires.

Our new S4000CH intelligent sensor stands as an example of the benefits HART. Standard HART commands make it easy for systems to configure and adjust the S4000CH to the particular requirements of the plant. The smart field device, for instance, can be tagged with a name for greater ease of use (ex. “combustible detector in boiler room”). Alarm and warning set points can be adjusted, delay times set, and alarms acknowledged or reset by simply sending a command. Such real-time, continuous access to device variables improves control.

Because the S4000CH is equipped with event logging, managers and technicians have access to time-stamped records of all maintenance performed on the device. Accurate entries for calibration, gas checks, and sensor replacement provide objective evidence of regulatory compliance. These records are particularly useful during quality systems audits, and since they are generated automatically, make producing documentation on demand more efficient.

The benefits of the HART-equipped S4000CH are not limited to better information management and predictive maintenance. Through HART, a user can check the status of the S4000CH unit and respond to a fault when it is issued. Guesswork is eliminated. Supplied with information about the nature of the fault and its frequency, power supply voltage, sensor voltage, and sensor life, workers can make accurate diagnostics about the condition of the device before setting foot on the field.

The S4000CH is suitable for use in SIL 3 applications and approved by FM, CSA, ATEX, GOST and has the CE Marking. It features a three-digit display and an explosion-proof housing, which allows all data to be processed locally at the sensor site. The detector is also available with an optional relay configuration that is appropriate for SIL 2 processes. The S4000CH features one-person calibration for ease of maintenance.

With its dependable catalytic bead sensor, the S4000CH monitors combustible gas and vapors within the lower explosive limit (LEL) and provides status indication and alarm outputs. In addition, the S4000CH is equipped with relay contacts that can be used to indicate an alarm or fault condition. In addition to HART, configurations with relays and dual redundant Modbus are also available. The S4000CH is the direct replacement of our S4000C. Both products share the same housing, but the electronic boards are not interchangeable. Retrofit kits are available to upgrade S4000C’s to S4000CH’s.

Incorporating HART into the S4000CH enhances the usefulness of the combustible gas detector, permitting users to integrate the device more fully into process automation. Benefits of the S4000CH derived from the communication protocol become increasingly evident with the size of the detector installation. Beyond maintenance, plants stand to gain from greater workforce efficiency, asset performance, and fewer unplanned shutdowns.

Learn more about the S4000CH

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General Monitors, Inc.
26776 Simpatica Circle
Lake Forest, CA 92630

Phone: 949-581-4464
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