Recently we have published a series of articles about (remote) condition monitoring. We described 4 reasons to install a remote vibration monitoring system (1) and listed the necessary hardware for a well-functioning remote vibration monitoring system (2). In this article we give a practical example of vibration protection and monitoring at a power plant.
The structure of the systems is completely dependent on the customer’s requirements and the specifications/configurations of the machinery where condition monitoring and protection is desired. Therefore Istec builds complete turnkey solutions for vibration measurements, temperature measurements and overspeed protection. Istec takes care of the entire process, from equipment, engineering and design of the end product, to ATEX compliance, functional safety (SIL), acceptance tests and commissioning. Istec upgrades existing systems or replaces / supplies complete instrumentation cabinets and retrofits.
As the protection and condition monitoring are completely customer-specific there is no standard solution. The example below is therefore intended to illustrate how Istec can complement a machine monitoring system with a condition monitoring system that allows remote access at a power plant.
Protection and condition monitoring at a power plant
In this example the protection and monitoring system of Vibro-meter is used: The VM600. This is one of the most widely used protection systems for monitoring and protecting vibration on critical rotating machinery in the power industry. Due to the modular construction, consisting of standard 19” cards, the system can be built completely according to the requirements of the end-user. Despite the cards being in the same rack, the protection signals are strictly separated from the condition monitoring signals in accordance with API 670.
The image above shows the complete system structure for protection and remote condition monitoring of critical machinery in a power plant. Note that monitoring and protection signals are strictly separated from each other (in accordance with API 670). The red line follows the monitoring signal and the green line the condition monitoring signal (CMS).
Protecting critical machinery is crucial in preventing potentially dangerous situations and/or serious damage to the machines. A protection system ensures that an alarm is triggered in time or the machine is switched off when a certain limit value is exceeded.
The gas turbine and steam turbine are both protected and monitored by a VM600 vibration protection and monitoring system. The system receives signals from various sensors, such as: proximity sensors, accelerometers and dynamic pressure sensors. Furthermore, four pumps are protected and monitored by a VM600. The system receives signals from accelerometers and proximity sensors. The monitoring signals are sent from the protection system to the DCS.
By performing periodic analyses, the condition of these critical machines can be monitored and any deviations in machine behaviour can be recognized. In this way, corrective actions can be carried out at scheduled times and unexpected damage can be prevented. This method contributes to an increased efficiency of the maintenance work and to the operational life of the machines.
The VM600 systems which monitor and protect the steam and gas turbine send the condition monitoring signal (CMS) via an UTP (ethernet) to a local server PC with a VibroSight lincense. Via an OPC (open communication protocol) the signals of the DCS can be integrated in the VibroSight platform.
The vibration data is stored locally, but the vibration specialists of Istec can, if the customer wishes, log in to the VibroSight platform via a secure connection and view and analyse the data remotely. This allows Istec to be responsive towards the customer and offer expertise when the customer requires it.