Objective

Automatic multiple compound average value computation of H₂S ; RSH ; THT ; Total sulphur compounds and Odorization factor.

General

Analysis results are set in a Real Time DataBase (RTDB).
The Math Module gathers these results with previous one, computes if necessary the averages values and other alarm triggering. All these data are also set in another place of the RTDB.
The Modbus Driver continuously collects the data it needs from the RTDB and make them available to DCS or SCADA with Modbus protocol.
To test the communication, the Modbus client requests need to be setup in the host DCS or PLC.
The monthly historical files gather all substance results to be archive in CSV format which could be easily imported in a spreadsheet or a database.
The calibration standard DMS results could be log on request in a monthly separated file.

Alarm computing

All alarm computing is performed at every result release.
All alarm can be acknowledged from Vistachrom suite.
All alarm thresholds are gathered into a dedicated .ini file.
All alarm status changes are time stamped and logged into a monthly text file.

Security handling

Follow up of the calibration substance :

⇒ A deviation alarm against its target value is computed.
⇒ The target value is calculated after each calibration performed during the analyzer metrological follow up.

Hardware fault handling :

⇒ The Math module watch for all error reported by the analyzer, check if it is a valid error and trigger a specific hardware alarm.
⇒ The alarm is trigged if the analyzer doesn’t deliver some result before a predefined delay.

Software fault handling :

⇒ Every Vistachrom suite runtime program generates a life signal in the RTDB that could be reported to external DCS with the modbus driver. These life signals testify the full working of each softwares.
⇒ All hardware and software alarms are time stamped and logged in a monthly system text log file.