Precision and speed in the analysis of medicinal gases at Praxair
The monitoring system that is used for control, data acquisition and management of events and alarms is software SCADA of Factorylink version 3.5, with a license for 75 points. The Scada, in turn, is connected to an IBM AS400 platform to save the results of the analysis.
Its operation
Once the process begins, the Scada sends the information to the automaton to start the specified sequence of analysis. Different processes occur depending on the type of bottle or tank. To get the correct measurement of the Analyzer, is first performed a check of the team through a botellas-patrones to be used as references. The Analyzer compares the value of the sample with the stored reference value, thus showing the concentration of the sample gas. The sequence begins with the opening of the electro-válvulas gas reaches up to the Analyzer where the value of the sample will be collected.
This value will be checked if it lies within the established parameters. If so, the value is recorded and stored in the AS400 through the Scada, leaving the system ready for further analysis.
The following teams are used to analyze the medicinal gas:
- Analyzer that measures the purities of O2, CO and CO2 of the sample.
- Analyzer that measures the humidity which has sample.
- Analyzer that measures concentrations of NO and no.2 in N2or.
- Analyzer that measures the concentration of N2or
- Analyzer that measures the concentrations of CO and CO2 into N2or.
All these teams are controlled through the automaton with communications CJ1W-SCU21 cards and by means of a communication protocol for each one, developed in CX-Protocol. Through these communications you can collect the values of measurement of the analysers and perform remote equipment calibrations.
To ensure constant sample to the analysers, also you have to control the flow rate that is provided, where used some drivers of mass flow controlled by communications CJ1W-SCU21 card where the value of the flow of the sample is collected and you select the type of gas which will pass through the meter. The analog input card is used to collect the different values of temperature and pressure signals of 4 to 20 mA.