Given your AMR application, which wireless technologies/protocols/standards make the most sense? There are a number of considerations to factor into your decision: Is the meter located below grade, or in another radio-hostile location? Is the meter battery-powered? Do you want to communicate to an in-house display, a walk- or drive-by reader, or to a fixed network? What protocols are other local utilities using…and why?
1. What wireless technologies are used for AMR?
There are several different wireless technologies used for AMR (automatic meter reading) systems in the world today, based on the specific needs, availability of power (battery driven or not), local radio regulations, density of meters, how often meters need to be read, the infrastructure, etc. Some radio networks are based on proprietary communication protocols, and others are based on industry standards. Among the standardized protocols we find Wireless M-Bus, and 6LoWPAN-based solutions such as Wi-SUN.
Wireless M-Bus is developed for battery-operated meters, such as water, gas and heat (heat cost allocators). It has always had a big emphasis on low-power operation. Later the Wireless M-Bus standard was extended to include communication on 169 MHz. This frequency has improved the range and reliability for reading water meters that are located in basements or pits, or gas meters in steel cabinets; in other words, not so radio-friendly environments. Narrowband operation at 169 MHz is a robust solution for almost any harsh environments.
6LoWPAN is a newer technology that enables IPv6 communication all the way to the end node. Due to a relatively high power consumption, it is used for electricity meters but not for water and gas. ZigBee IP and Wi-SUN are examples of protocols that? use 6LoWPAN as part of their protocol stack.
Radiocrafts offers solutions within all these technologies, and more information can be found on our product pages. Wireless M-Bus is supported by the MBUS3, MBUS4 and MPC1 products. The ZigBee protocol is supported by the ZNM products. And 6LoWPAN protocols can be run on the IEEE 802.15.4 platforms.
2. What is the most commonly used wireless technology used in Europe for AMR?
The most commonly used wireless technology in Europe for meter reading is Wireless M-Bus. The installation base is tens of millions. The first solutions used mode S and T on 868 MHz. These have later been complemented with mode C, also at 868 MHz, optimizing current consumption and thereby enabling drive-by reading which require? more frequent transmissions. Mode N using ultra-narrowband technology at 169 MHz is growing in popularity due to its long range and robust operation even in radio-challenging environments typically seen by water and gas meters. Radiocrafts has a leading role in the standardization of narrowband technology at 169 MHz in CEN, which publishes the EN 13757-4 norm.
3. What is Wireless M-Bus?
Wireless M-Bus is a European Norm for utility meter communication. It is standardized in EN13757-4. This radio protocol is widely used for electricity, gas, water, heat meters and heat cost allocators. Wireless M-Bus also supports other types of environmental sensors. Together with the rest of the EN 13757 standard series, Wireless M-Bus makes up a complete protocol stack with security mechanisms and definition of data formatting for the application layer.
The Wireless M-Bus standard is optimized for battery operation, targeting battery lifetimes of 15 – 20 years, and thereby reducing the operational cost of the meter reading system. The low-power consumption is due to the “bubble up” strategy for meter data: the meter listens for commands in a short time window after the transmission. This means the transceiver can be in sleep mode most of the time, saving power. This is further supported by very small overhead in the frame format and efficient data coding.
The standard has taken advantage of the new frequency band at 169 MHz to make a narrow-band solution using 12.5 kHz channels. The relatively low frequency (VHF band) and the narrow bandwidth give very long communication range and robustness in difficult radio environments. This is particularly important for reaching water and gas meters.
4. What solution should I use for battery-operated meters, such as for water, gas and heat?
The preferred solution for battery-operated meters is Wireless M-Bus. For in-house communication between meter and a local concentrator, mode T and C at 868 MHz are most commonly used. For longer range communication with a central concentrator, mode N at 169 MHz is preferred. Radiocrafts supports these standards with the MBUS3 and MBUS4 protocols. The MPC1 (M-Bus Pulse Counter) is a complete implementation of an autonomous pulse counter that can directly interface any mechanical meter with pulse output.
5. What solution should I use for electricity meter reading?
Electricity meters with constant access to power (and back-up battery during black-outs) may use mesh protocols to extend the network coverage. Radiocrafts offers Tinymesh, ZigBee and 6LoWPAN solutions .
Battery-operated meters can be used together with a mesh, but these nodes will not take part in the forwarding of messages in the mesh. Tinymesh is a low-cost mesh solution that can operate on any frequency band set by local regulations. It will carry different application protocols transparently, interfacing with the meter through a UART interface. Multiple gateways can be added as the network grows.
ZigBee networks are mostly used for in-house communication. The ZNM (ZigBee Network Module) and ZNM-SE (Smart Energy profile) are easy-to-use solutions offering the complete ZigBee stack in a module with API interface. 6LoWPAN is a standard for how to compress IPv6 packets to fit into a IEEE 802.15.4 radio packet. ZigBee IP and Wi-SUN use this technique, and can run on our IEEE 802.15.4 platforms.
As you can see, there are many factors to take into consideration before settling on one wireless AMR protocol over another. Radiocrafts is eager to help you design a robust wireless AMR system that serves all of your network needs — and minimising the long-term cost of the system. With tens of millions of field-proven module installations, our application engineers are uniquely qualified to take you through the entire AMR design process. Start the conversation today!