En-Meter M

Why did I get into product development?

The box, which attaches to the power cord, can monitor the power consumption of an electrical appliance and send the data via the Internet of Things (IoT) network. This is how the smart probe works for contactless indication of appliance activity and power consumption, which is currently undergoing the final stages of field testing. The team of doc. Jiří Vodrážka, head of the Department of Telecommunication Engineering at FEL CTU, has long been working on IoT technologies and communication systems for smart grids and smart metering. En-Meter M is the next in the family of smart solutions.

What problems does it solve for its customers?

En-Meter M is suitable for the following applications:

• Monitoring and evaluating the status of electrical appliances, e.g. street lighting lamps, pumps, heating systems.
• Indicative monitoring of electrical energy at any point on the power cable for one or a group of appliances.
• Data acquisition for optimizing energy consumption in companies, institutions, buildings.
• Monitoring of consumption with the possibility of generating alarms in case of unexpected behaviour (detection of undesirable activity in the building).

The difference with existing standard energy metering solutions is that the innovative "En-Meter M" probe does not need to be connected to an electrical circuit and can be used to monitor energy consumption virtually anywhere and at any time.

It uses non-contact sensing with a magnetic sensor near the power cable of any appliance, group of appliances or an entire power branch. The sensor is attached to the power cable and simply fixed mechanically with e.g. tape. It has its own battery power supply and sends data wirelessly via the Sigfox global IoT network or the LoRa network. The data can then be monitored on a web portal, including conversion to estimated power consumption.

The uniqueness of the solution lies, among other things, in the possibility to configure the mode of data sending and choose the method of data evaluation. We foresee the use of a wide range of companies and institutions that need to have an up-to-date overview of electricity consumption and data to optimize consumption. The solution allows them to reduce costs by being able to, for example, direct energy supply to times when the rate is more cost-effective.

Product development phase

At the moment, the probes are being tested in Řež near Prague, where the developers are verifying the monitoring of street lighting lamps. They are also testing consumption monitoring with the possibility of detecting unwanted activity in the monitored object.

Thus, monitoring a whole group of lamps with a single device at a low cost can help turn ordinary lamps into something approaching intelligent lighting. The probe thus becomes a promising component in the concept of "smart cities", but it also has the potential to be used in industry to monitor various machines and keep an eye on their operation, for example in predictive maintenance.

The solution is protected by the utility model "Device for remote non-contact monitoring of the activity of electrical appliances" (registration No. 34434).

Method of commercialisation

CTU is able to supply units. We are looking for a partner for mass production.

Technical specification

Technical specifications:

• Wireless Sigfox transmission in ISM 868MHz band
• Display of values on the web portal or via API
• Sensing method: non-contact (magnetic sensor)
• Measured power range typically: 0.1 to 4 kW
• Power supply2x CR123A batteries, lifetime typically 2 years with 1 hour interval readings
• Operating temperature range: -20º to 85º C, degree of protection: IP40
• Dimensions (without cable clips): 65x45x32mm
• Indication of electrical appliance activity type on-off
• Indicative measurement of current draw and power consumption of the electrical appliance
• Estimation of energy consumption based on a sequence of readings
• Selectable reading intervals (typically 1 day, 1 hour, 15 minutes)
• Easy installation - the sensor is simply strapped to the power cord
• Inexpensive operation - the sensor is powered by a long-life battery and the communication usage fee is very low (annual subscription)