Maintenance and Repair of Process Control Systems

Maintenance of process control systems (PCS) is a comprehensive set of activities involving the diagnosis, preventive maintenance, and repair of automated process control systems. Regular maintenance helps identify malfunctions before equipment fails and, in the event of an emergency, determine the cause of the failure and restore system operation.
Promanalit’s specialists perform scheduled and emergency maintenance of process control systems at industrial facilities. The work covers field equipment and instrumentation, automation devices, software, and SCADA.

What Is Included in the Maintenance of a Process Control System

Maintenance of the process control system includes inspecting the condition of equipment and software, diagnosing malfunctions, performing preventive maintenance, and configuring the system. The purpose of this maintenance is to ensure the system operates normally and to identify problems that could lead to malfunctions or a shutdown of the process.
As part of maintenance, equipment is inspected at various levels of the process control system:

• Lower level (instrumentation and control): inspection, cleaning, and calibration of sensors, flow meters, gas analyzers, and actuators.
• Middle level (automation): diagnostics of PLCs (controllers) and I/O modules; inspection of terminal connections and supply voltages in control cabinets.
• Upper level (software): verification of SCADA operation, display of process parameters on the operator workstation, data archiving, and maintenance of fault logs.

Special attention is paid to the correctness of data transmission between system levels. Signal loss, unstable values, or communication errors may be related to field equipment, communication lines, or automation devices.
Based on the diagnostic results, the technical condition of the process control system is determined, along with a list of necessary work. Any detected malfunctions are corrected as part of routine maintenance or repairs.

Process Control System Maintenance: Diagnostics and Troubleshooting

Repairs to a process control system are required in the event of equipment failures, signal loss, communication failures, software errors, and other malfunctions that prevent the system from performing its intended functions. The work begins with diagnostics: before replacing equipment or changing software settings, it is necessary to determine the cause of the malfunction.
The source of the malfunction is not always where the error manifests itself. For example, the absence of a parameter on the operator’s screen may be related to measuring equipment, signal transmission, or signal processing within the system. Therefore, when troubleshooting, the entire data flow chain is checked. 
Once the fault has been localized, specialists restore the system to full operation: they correct the identified faults, make the necessary adjustments, and, if needed, repair or replace failed components. After the work is completed, they verify that the restored section of the process control system is functioning correctly.

When Process Control Systems Require Diagnostics or Maintenance

Not all automation malfunctions immediately lead to a complete shutdown of the equipment. They may be preceded by intermittent errors, unstable readings, or communication failures between individual system components.
Diagnostics are necessary in the event of signal loss or incorrect signal display, regular data exchange errors, untimely activation of automation systems, SCADA malfunctions, or failures of individual components. Inspections are also conducted after equipment replacement or modifications to the existing system, if these changes affect its operation.
Scheduled maintenance is performed before such signs appear—according to a schedule agreed upon for the facility.

Scheduled and Emergency Maintenance

Promanalit performs both scheduled maintenance and repairs in the event of malfunctions and emergency breakdowns.

The frequency of scheduled maintenance is determined based on the system’s specific characteristics and operating conditions. In the event of an emergency call, the primary task of service technicians is to identify the source of the malfunction and restore normal operation of the automation system.

Maintenance and Repair of Process Control Systems in Kazakhstan

Promanalit provides maintenance services for operational process control systems at industrial facilities in Kazakhstan. Our specialists work with instrumentation and control equipment, automation systems, and SCADA systems, performing diagnostics, configuration, scheduled maintenance, and emergency system restoration.
Before beginning work, our specialists assess the existing process control system and its technical condition. When servicing a system already in operation, it is important to consider the existing automation architecture and the specific characteristics of the process, rather than treating a faulty component in isolation from the rest of the equipment.
Promanalit also performs repairs and upgrades of process control systems. The company has its own calibration laboratory and service department. Specialists perform verification and calibration of measuring instruments, so these tasks can be carried out in conjunction with the maintenance of equipment and automation systems.