This product is obsolete and has been replaced by the S5000. The mounting footprint and cable entries of the two transmitters are identical, which makes retrofitting simple.

The General Monitors S4000CH Intelligent Sensor is a microprocessor-based transmitter designed for use with General Monitors’ catalytic bead sensors. The unit features one-person calibration and can virtually self-calibrate by simply activating a magnetic switch and applying gas. It is designed to monitor combustible gases and vapours within the lower explosive limit (LEL) and provide status indication and alarm outputs.

All S4000CH electronics are contained within an explosion-proof housing, allowing sensor information to be processed at the sensor site. The detector uses a 4-20 mA analogue output signal that is proportional to 0 to 100% LEL gas concentration at the sensor. In addition, the S4000CH features warning, alarm, and fault relay contacts that can be used to indicate an alarm or fault condition, as well as dual redundant Modbus or HART communication.

Configurations with relays, Modbus, and HART are available to meet a wide range of needs.

The S4000CH also includes a three-digit LED display. This local display continuously indicates gas concentrations during normal operation or in Gas Check Mode, calibration prompts during Calibration Mode, display codes during Setup Mode, and eight fault codes.

The S4000CH has four operating modes

• Normal operating mode in which alarms are active and the display and 4-20 mA readings are proportional to gas concentration at the sensor.
• Gas check mode that allows users to apply gas and check sensor response while alarm outputs are inhibited.
• Calibration mode in which gas is applied to the sensor to calibrate the unit.
• Setup mode allows users to review and change setup options, including relay settings, calibration level, and Modbus parameters. Selecting Setup Mode on the S4000CH is accomplished by using the magnetic switch, HART, or Modbus command.

Features

• Fully automatic calibration is available with the Automatic Remote Gas Calibrator (ARGC).
• HART and Modbus communication provides complete status and control capability in the control room.
• Calibration, calibration check, and setup modes simplify operation and maintenance.
• Remaining sensor life indication reduces downtime by providing an estimate of the sensor’s remaining lifespan.