In the 21st century, we have always enjoyed the convenience brought by electricity, which also affects our clothing, food, housing, and transportation. It can be said that electricity is all around us at all times.
Electricity is something we are very familiar with, and we are used to its existence. But on the other hand, electricity can also be quite unfamiliar to us because it is invisible. We cannot intuitively understand electricity, nor can we directly obtain the magnitude or level of current. We can only obtain information about electricity through measurement. Therefore, a powerful, easy-to-use, and user-friendly electricity monitoring system is essential.
Overall Design Introduction
This article introduces a smart electricity monitoring system based on a Weintek touchscreen. The Weintek touchscreen acts as the information processing center, capable of reading various parameters from the lower-level device (electricity meter), processing these parameters, and providing an intuitive display. The electricity meter acts as the data detection center, accurately measuring and obtaining various required data. The GPRS modem acts as the alarm information dissemination center, enabling the dissemination of alarm information via SMS.
Communication settings
This system comprises four devices: a Weintek cMT-3151 touchscreen, a Panasonic KW9M-A power meter, a Panasonic CT024A-100 AC transformer, and a GPRS modem. The cMT-3151 acts as the data processing center, communicating with both the power meter and the GPRS modem to send or read commands to both instruments and process the received data. The power meter and AC transformer work together to obtain real-time parameters such as current, voltage, frequency, and temperature of the monitored line, and calculate parameters such as power and power factor from these parameters. The GPRS modem primarily implements the SMS alarm function; alarm messages are sent from the cMT-3151. Research indicates that the power meter supports RS-485 communication, and the Weintek touchscreen has already provided the corresponding driver. The GPRS modem supports RS-232 communication and can recognize specific data formats; therefore, a proprietary communication protocol can be used to enable it to recognize the required operation content. The device settings on the Weintek touchscreen programming software EasyBuilderPro are shown in Figure 1.
Figure 1 Communication settings screen
Graphic Design
The system features four main screens on the touchscreen: the main energy management screen, the real-time power consumption screen, the alarm query screen, and the alarm setting screen.
(a) Main screen energy management page
As shown in Figure 2, the main interface energy management screen can clearly show the electricity consumption and power usage rate of the day. The power usage rate is displayed in several ways, including multi-status indicator lights, bar charts, and fractional and percentage displays.
Figure 2 Energy Management Screen
(ii) Real-time electricity consumption
As shown in Figure 3, the real-time power consumption display can show the instantaneous values of various currents and voltages in the three-phase power supply, as well as the instantaneous values of active power, reactive power, and apparent power, along with the power factor and the measured ambient temperature. In addition, a trend graph function has been added. The trend graph displays the instantaneous value of active power, which is obtained from data sampling with a sampling period of 2 seconds and is displayed within a 10-minute interval, as shown in Figure 3.
Figure 3 Real-time electricity consumption screen
(III) Alarm Inquiry Screen
As shown in Figure 4, the alarm screen displays the alarm event display element, which shows all historical alarm information. Alarm information includes over-limit power alarms, overcurrent, overvoltage, undercurrent, undervoltage, and equipment overheat alarms. Once the detected conditions meet the alarm generation criteria, the alarm sequence number, date, time, and corresponding event information will be displayed on the event display element, allowing users to easily view alarm information and understand power usage.
Figure 4 Alarm screen
(iv) Alarm setting screen
As shown in Figure 5, the alarm settings screen mainly consists of three sections: alarm settings, power notification, and fault standby. The alarm settings section is mainly used to set parameters such as whether an alarm is needed, alarm values, and whether an SMS alert should be sent when an alarm occurs.
If the corresponding parameters are selected, the alarm information will be displayed on the alarm query page when the detected value meets the alarm conditions. Simultaneously, the system will check if SMS alarms are selected; if so, basic alarm information will be sent to the corresponding mobile phone. The power push section mainly sets the mobile phone number, daily power push, and weekly power push. Setting the mobile phone number is for pushing power consumption data and sending alarm information to that phone. The fault standby section aims to determine if the power consumption is abnormal by setting upper and lower limits for the detection current. When abnormal power consumption occurs, the power will be immediately disconnected; the disconnection time is determined by the standby time.
Figure 5 Alarm settings screen
Conclusion
This system, composed of a WEINVIEW cMT-3151 touchscreen, power meter, AC transformer, and GPRS modem, is applied to the field of smart electricity use. It ensures that users can monitor the power consumption of equipment or factories in real time, monitor power anomalies, obtain abnormal information, and formulate corresponding measures based on the obtained power consumption information to achieve greater benefits.
