Placing electrical equipment or systems in electrically-safe work conditions may seem simple, but there are several factors to consider. Proper planning and preparation will make any type of testing simpler and safer. Having to stop work to fetch other tools or test instruments interrupts focus and can contribute to accidents. Traffic in the area can […]
The insulating properties of power cables deteriorate with time and, at some stage of life, the cable will be unable to meet performance requirements, and suffer repeated failures. End of life (EOL) will vary with the cable type, the installation and conditions under which the cable is operated, and will vary from installation to installation. […]
Electrical diagrams are vital for any factory for the same reason that makes them mandatory for aircraft or nuclear plant operators: personnel safety. Although the importance of electrical diagrams cannot be over-emphasised, there are other reasons for using them which may not be as obvious. Safety of machinery For example, interlocks intended to protect expensive […]
When transformers and neutral conductors in balanced circuits overheat and circuit breakers trip for no apparent reason, the cause often lies with harmonics. Harmonics are the by-product of modern electronics. They are especially prevalent wherever there are large numbers of personal computers, adjustable speed drives and other types of equipment that draw current in […]
An investigation into the effect of varying the installation angle of the earth rod between 0° and 90° for a small substation earth grid. Earth rods connected to earth systems are used widely to reduce the resistance of earth electrodes for substations [1], as well as other applications. It appears, however, that earth rods […]
It is not possible to protect earth electrodes from corrosion by separating the metals from the soil as all common sheaths have a high electrical resistance and eliminate the effect of the earth electrodes. Earth electrodes made of a unitary material are prone to corrosion due to corrosive soils and the formation of concentration […]
This article illustrates the widespread lack of knowledge on the subject of earthing. We find that the implementation is often inadequate at locations where effective earth electrodes are required. It is generally acknowledged that there is a lot of confusion among those responsible for the implementation of earthing practices. The confusion is at all […]
Longer lifespan, reduced size and weight, faster recharge times and declining prices have made lithium-ion batteries an appealing energy storage technology. This article answers some questions new users may have. In the simplest of terms, a battery is an electrochemical device that stores energy and releases it as electricity. Batteries are typically organised in […]
The advantages and disadvantages of the predictive, preventative, and run-to-failure maintenance practices, and how preventative maintenance programmes are enhanced using thermal imagers. Typical predictive maintenance includes tasks such as vibration analysis on machines, acoustic, ultrasonic, and infra-red (IR) thermography inspection on electrical systems. Table 1 provides a comparison of predictive, preventive, and run-to-failure maintenance. […]
This article provides a basic overview, covers some of the misconceptions and considers some of the implications of safety and safety integrity level (SIL) on a process control loop. Safety instrumented systems (SIS), often referred to as emergency shutdown systems (ESDs), are put in place in addition to the basic process control system (BPCS) […]
