Electricity + Control 2019

PLANT MAINTENANCE, TEST + MEASUREMENT round up

Vibration monitoring in rotating machines

predict the condition of a machine and to plan maintenance. The condition of most common machinery can be determined instantly with alarm levels that are programmed into the product. Frontline mechanical troubleshooting teams and machine opera- tors at high-end process facilities (in petrochemical, pulp and paper, primary metals, utilities, food and product industries, for example) are particular about inconsistencies in results when using vibration screening devices. Fluke 805 provides reliable, repeatable results due to the innovative sensor and sensor tip design which minimises measurement variations caused by angle or pressure. The sensor design compensates for the pressure applied during measurement and provides reliable results for overall vibration (10 Hz to 1 000 Hz)

Vibration in rotating machinery is the back and forth movement or oscillation of a machine and components such as drive motors, driven devices (pumps, compressors) and the bearings, shafts, gears, belts and other elements of mechanical systems. Vibration itself is not a problem. Excess vibration, however, is usually a symptom of internal issues, such as bearing failure, im- balance, misalignment and looseness that will shorten the equip- ment’s lifespan. It is reported that more than half of unplanned downtime is attributed to mechanical failures. Many things can affect the longevity of a machine, but once the first signs of failure appear, it is generally a matter of months before it fails completely. Vibration testing provides a way to determine where a machine is on the failure curve and allows maintenance teams to act as need- ed. The higher the overall vibration of a machine the worse the con- dition is. The Fluke 805 vibration meter from Comtest measures overall vibration, bearing vibration and temperature simultaneously. Bearing condition is assessed automatically using Crest Factor Plus (CF+) and temperature is often used as a ‘second opinion’ to confirm the bearing assessment based on vibrations. With Fluke Connect (FC) for FC enabled models, or a free Excel template, trends can be plotted on all available parameters. These help to Mitsubishi Electric Europe’s MEprotect digital protection relays provide reliable, secure protection and control for electrical equip- ment such as motors, generators and transformers in industrial applications. With its robust protection functions MEprotect increases plant availability while optimising the link between the control system and the electrical asset base. This allows savings in installation, commissioning, operation and maintenance of the assets. MEprotect is a flexible and modular intelligent protection sys- tem for low and medium voltage equipment. Using a common hard and software platform, it is designed to scale from simple to highly critical applications. It is typically installed in the motor control centre for low voltage applications or in switchgear sys- tems for medium voltage use and links the higher-level automa- tion system and the protected equipment intelligently via fieldbus technology.Due to its minimal size and modular design, the relay is ideal for use where space is limited, as in intelligent motor or

and bearing measurements (4 000 Hz to 20 000 Hz). The vibration meter provides a four-level severity scale for overall vibration and bearing condition and users can readily assess the severity of the situation based on text-based alerts. Enquiries: COMTEST.Tel: +27 (0)10 595 1821, email: sales@comtest.co.za The Fluke 805 vibration meter assists in monitoring the condition of rotating machines and their component parts.

Intelligent energy asset protection

power control centres. It is designed for the toughest industrial applications. Features such as online monitoring, diagnostics and event logging support proactive, preventive maintenance and con- tribute to reducing asset downtime and maintenance costs. The MEprotect relay is fully configurable with either the MEpro- tect/emp software or a human machine interface (HMI). Access to the unit to operate, configure or change parameter settings is password protected with multiple access levels. Event records can be downloaded to a laptop for further analysis. The application also has a PC-based data recorder and a spectrum analyser which can be used to analyse machine performance, power supply qual- ity and other factors. Mitsubishi Electric’s MEprotect and other factory automation tools are available in South Africa from authorised distributor Adroit Technologies. Enquiries: Adroit Technologies.Tel: +27 (0)11 658 8100 or visit: https://adroittech.co.za