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发布日期:2021年11月30日

South African Government COVID-19 Corona Virus Resource Portal

. For all the information you need to know visit the South African Government COVID-19 Corona Virus Resource Portal. Emergency Hotline: 0800 029 999 WhatsApp Support Line: 0600-123456 See /

Public lighting: Lighting the way to smart city development

Public lighting is one of the services most visually seen by the general public within a city (though it almost goes unnoticed). Lighting provides a sense of visual safety and security. This improved sense of safety and security will often lead to an increase and further promotion of community activities, events, sport, trade, industry and […]

Choosing a variable frequency drive or soft starter

When accelerating an AC motor to full speed using a full voltage connection, a large inrush current may be required. Additionally, the torque of the AC motor is mostly uncontrolled and can shock the connected equipment, potentially causing damage. Variable frequency drives and reduced voltage soft starters can reduce inrush currents and limit torque thereby […]

Understanding the basics of power measurement theory

Electrical power applications are changing rapidly which means the load on the electric network is changing: more harmonics and more risk of unbalance. This so-called “bad” power costs money and wastes energy. This article provides some basic theory to understand what is happening with today’s electrical applications. Apparent power To understand the relation between active […]

Measuring high currents with small current sensors

Modern current measurement trends in uninterruptible power supplies (UPS) and renewable energy systems is towards smaller physical size, higher current ranges, faster response times and lower cost. The simplicity of open-loop sensors makes them an attractive solution for attaining these objectives. This article discusses three new families of sensors which allow the nominal current to […]