We live in an era of technological progress. In this era, we have to live a comfortable life mastered the basic skills required. Our immediate environment may be very comfortable, but the undeniable existence of worrisome global environmental issues; Therefore, developing methods to reduce the environmental impact of the moment has become an extremely important thing. Although governments still in dispute what the international community must take action, but the company has adopted far-sighted solution to a better understanding of what we can do.
LEM
       Energy efficiency is a win-win thing; from every point of view, lower energy consumption is equivalent to reducing energy costs. Prevent us from further attention to the energy problem is cognitive; from a country, we may be aware of the existence of energy problems, but lack of information will prevent us from taking direct action to improve the situation. If knowledge is power, which means that our possession of knowledge about energy use, the more will help us to take positive action to reduce power consumption.
LEM
       Utility companies provide electricity meter is to monitor the situation, but the installation of electricity meters are often only rough data is intended to enable utility companies can charge customers. Auxiliary measurement (sub-metering) is relatively late to take the power industry method of measuring the large companies and electricity to more accurately monitor energy use, to provide them with these energy sources to reduce energy consumption and direct and indirect costs of the necessary information .
However, this knowledge has a cost. Currently, utility companies do not provide support to all end users measured by energy users, so the burden of initial investment. Save money by measuring the return on this investment, but the greater investment, payback period longer. Most of the auxiliary meter installed facing this reality: not only the complexity of installation and commissioning, and must be halted.
LEM
      Grasp the trend of wireless telemetry technology, developed far beyond the traditional measurement tools supporting products; to provide complete energy management solution, not only easy to install, and almost no testing, while the use of wireless networking technology automatically for easy expansion and maintenance.
LEM
      Known to the leading sensor technology, these sensors for a variety of forms of data acquisition applications, including telecommunications, medical and industrial applications.
LEM
       The expertise developed through a series of monitoring devices, not only the accuracy of measurement of energy use than other currently available solutions, and to wirelessly transmit the information. This reduces costs and reduce the inconvenience of installation - which is the solution to install a secondary measure important factors to consider.

      Radio Menu (Wi-LEM) solution consists of multiple nodes, the minimum configuration must have a measuring point (EMN), and a gateway. EMN Wireless data acquisition and connected with the gateway, and gateway provides the interface with a personal computer for storage and processing collected data.

       EMN also measured both the current-voltage measurements, and direct transmission of power from the circuit under test, which means that no additional installation of power. As a result of the new retractable current transformer (see below) to measure current, used to measure voltage wiring connection is the only device required "broadcast only" link. EMN only 2 watts of power, through the measurement of voltage and current transformer for active, reactive and apparent power, then the data wirelessly to the gateway for processing.

       Measuring active energy consumption is the major utility companies used accounting methods, and therefore the most important method. Able to clearly measure its own active energy consumption, power management can be improved, and the measurement accuracy, can improve billing accuracy. Active energy measurement of the end-users can actually make a comprehensive energy conservation program, it will continue to play an important role in the future. Consumption function can not accurately determine the power factor of power sites. With the various types of electrical devices on the line after another run, this situation will change, many utility companies are now charging under the power factor, which means that the user must know when to meet their own energy use set by public utility companies limits. Measuring instrument using the traditional hard to do this.

      EMN energy measurement accuracy of line with IEC 62053-21 standard, while 10% of its rated power in the case, in fact, more than 1% minimum accuracy rate. LEM's estimates show that, EMN in only 1% rated power conditions, the measurement precision of 1%.

      Secondary metering solutions One of the limitations now facing the communication. Measurement results are generally wired connection through the use of transmission system, which will increase the installation cost and inconvenience. Wi-LEM Wireless network using the latest technology to handle all the communications group.

      Common industrial applications, building a reliable wireless network is a major challenge, wireless network group (Mesh network) technology but it can easily deal with. Mesh network node with multiple self-discovery to run, so if poor channel between two nodes - such as installing a new metal cabinet, the network itself will automatically re-order to find alternative routes. This method has become the IEEE 802.15.4 standard agreement, but was more common - but often wrongly - known as ZigBee. Although the use of IEEE 802.15.4 ZigBee standard, but they are not exclusive. In fact, most of the standard use of the wireless network group (Mesh network) does not use ZigBee protocol stack. Wi-LEM is true, LEM in the IEEE 802.15.4 network using the MODBUS protocol is running, and at the top of the stack by LEM own to ensure that Wi-LEM communications security between nodes. Wi-LEM can do to ensure reliability and security within the network, while using industry standard MODBUS protocol's advantages and make full use of IEEE 802.15.4 mesh networking standard self-discovery and self-healing properties. When data arrives at the gateway MODBUS standards have been met, then the standard RS232/422 MODBUS RTU transmission to a personal computer connected to enable personal computers to store data in the database and make the necessary analysis.

      In order to make a reliable mesh network, LEM also produces the network relay: no simple wireless configuration API. After the power, they automatically join the network, strong electromagnetic interference signal routing region as a supplementary channel, such as the use of reinforced concrete construction or the building contains a large amount of metal cabinets.

      Wi-LEM is an important advantage is the new retractable current transformer. Through careful precision mechanical and electronic design to overcome a major shortcoming of these transformers: accuracy. In essence, imprecise because it is difficult to accurately install retractable current transformer. Complete sets of specially developed solutions, and for the electronic processing of the drop type transformer circuit to eliminate this problem, simplify installation, can accurately handle several Transformer detected □ V. This breakthrough EMN and the Wi-LEM to allow for more accurate measurements, energy saving so as to provide essential information for program managers.

      In addition to EMN, Mesh node and Mesh gate outside, Wi-LEM sub-metering solutions include Wi-Pulse and Wi-Zone interface. Today most of the gas and water meters to provide a standardized international standard pulse output, access to Wi-Pulse interface is able to provide essential energy saving information for program managers. W-Zone nodes use the same wireless technology to provide temperature and relative humidity and other environmental information, but also help understand the energy use.

      Wi-LEM is a late rise of a new generation of products supporting metering industry, highlighting the energy management of the increasing importance of the field, but also reflect the final energy-hungry for positive steps taken to reduce energy consumption.