There are many applications for electrical submetering – for example, utilities can remotely monitor their customers’ electrical usage and bill accordingly, or the individual power consumption of industrial equipment can be tracked. Adding wireless capabilities allows increased convenience to electrical providers and consumers, real-time data collection, anomaly detection, and many other beneficial features. At Silicon Labs, we support the development of wireless circuit breakers with our wireless MCU devices, which offer robust solutions with low power consumption and advanced security features.
Electrical Submetering Requirements
There are multiple requirements to consider when designing for electrical submetering applications.
Footprint size is typically constrained so the device can fit in pre-installed electrical breaker boxes. The wireless submeter must fit around the electrical cables to take current measurements, be small enough to fit inside the box, and contain a wireless transmitter with MCU to send data to devices external to the system.
The mesh network Series 2 SoCs offer a compact solution for smart submetering. Two modules are shown below that provide interfaces for electric, water, gas, and steam meters.
Temperature is an important consideration for two reasons. First, a submeter must be able to withstand high temperatures that are generated as a byproduct of the high current and high voltage environment. Second, the operating temperatures of the components used in submeters must be considered as well. Components that are rated for temperatures of 85°C or higher are optimal choices for including in electrical submeters.
Low power consumption is a must-have. Larger power consumption may cause electrical interference on the current line being measured, leading to an inaccurate measurement. The transmit power of the wireless component must also be kept low in order to stay below limits imposed by regulatory bodies on RF emissions in the region; these emissions are higher in a given area as the number of sensors increases, so it is important for individual devices to keep power low. On this note, certifications for the wireless components are also beneficial, to ensure that the selected device meets regulations and safety requirements.
Network schema for gateway and sensor nodes. Based on your requirements - whether it be low power or footprint - make sure your applications are good candidates for electrical submetering.
The following questions can you help you determine if your application is a good candidate:
- Are multiple submeters reporting to one data collection device?
- Does the data need to be sent to the cloud?
- How often does data need to update?