Every metering site needs a way to get readings back to the platform. This article compares the three methods Sycous meets most often, wired MBus, wireless MBus and LoRaWAN, and explains the faults each one tends to produce. It is written to help you pick the right method for a site and to point you to the right fault finding guide when something goes wrong.
The short answer
| Method | Best for | Weak spot |
|---|---|---|
| Wired MBus | New builds and refurbishments where cable can be run to every meter. Very reliable once installed and powers the meters from the bus. | Cable faults, short circuits, breaks and wrong voltage. Hard to retrofit. |
| Wireless MBus | Retrofits where cable is impractical and meters are within range of a receiver. Open and vendor neutral. | Range through the building, battery life, mode and key mismatches. |
| LoRaWAN | Sites with meters spread widely or over several buildings, with infrequent readings and long battery life needs. | Coverage in basements and risers, gateway backhaul, tiny messages and slow reporting. |
How they compare
| Question | Wired MBus | Wireless MBus | LoRaWAN |
|---|---|---|---|
| How do readings travel? | Over a two wire cable to a master. | By radio to a receiver, often at 868 MHz. | By radio to gateways, then over the internet to a network server. |
| Is there a master that polls? | Yes. The master reads each meter in turn. | Usually not. Meters transmit on their own interval. | No. Meters transmit on their own and the network listens. |
| What powers the meter? | The bus can power it, so little or no battery use. | Battery. The radio is the main drain. | Battery. Very low consumption per message. |
| Typical reporting rate | Anything from minutes to daily, as polled. | Every few seconds to every few minutes, depending on the mode. | Usually hourly to daily. |
| What limits the range? | Cable length, number of meters and voltage on the bus. | Walls, floors and metal. Often tens of metres indoors. | Walls, floors and metal, but each gateway can cover far more meters. |
| Where does the connection to the internet live? | At the MBus master or gateway. A CMe2100 uses a SIM card fitted in the unit. A CMe3100 uses Ethernet. | At the gateway or receiver. The Elvaco Edge has a SIM card fitted. A CMeX50 works with a CMe gateway. | At the gateway. The ZENNER B.One Gateway uses a SIM card fitted in the gateway, with automatic change to Ethernet if available. |
| Sycous products | Elvaco CMeX10S, CMeX11S, CMeX12S and CMeX13S MBus masters with CMe2100 or CMe3100 gateways, and the Digi ConnectPort X4 Guru Gateway. | Elvaco Edge Wireless MBus Gateway, Elvaco CMeX50 Wireless MBus Receiver, Wireless MBus Repeater and antennas. | ZENNER B.One Gateway Indoor and Outdoor, with LoRaWAN capable ZENNER meters and sensors. |
| What is the most common fault? | A short circuit or a break on the bus. | Wrong mode, wrong key or radio disabled. | Gateway offline, join problems or weak signal. |
| Which guide do I use? | Quick Approach to Wired MBus and Data Logger fault finding | Quick Approach to Wireless MBus Fault Finding | Quick Approach to LoRaWAN Fault Finding |
Questions to ask when choosing
- Can cable reach every meter without major works? If yes, wired MBus is hard to beat for reliability.
- How many floors, walls and metal doors are between the meters and a receiver or gateway? Concrete and metal reduce radio range fast.
- How often do the readings need to arrive? Billing readings once a day suit LoRaWAN. Frequent readings for monitoring suit wired MBus or wireless MBus.
- Who will replace batteries? Wireless meters depend on batteries lasting for the life of the contract.
- What connection will the gateway or master use? A SIM based gateway needs good mobile signal where it is fitted, and an external GSM antenna can help in a plant room. An Ethernet based unit needs a safe, permanent network connection.
- Will the site grow? A radio network can add meters easily. A bus has a maximum number of loads.
Good to know: Mixed sites are common. A building may use wired MBus for the main heat meters, wireless MBus for retrofitted water meters and LoRaWAN for outlying blocks. Each part has its own fault pattern, so identify which method a meter uses before you start fault finding.
Faults that look the same but are not
| Symptom | Wired MBus cause | Wireless MBus cause | LoRaWAN cause |
|---|---|---|---|
| One meter not reading | Break in the cable to that meter, wrong address or meter in sleep mode. | Radio disabled, flat battery, wrong key or out of range. | Join failed, poor signal or flat battery. |
| A whole floor not reading | Break in the riser cable between floors, or short circuit. | Receiver out of range of that floor. | Weak signal through that floor to the gateway. |
| Every meter not reading | Master faulty, no mains, or data logger offline. | Receiver offline or wrong mode set. | Gateway or its internet connection offline. |
| Readings present but wrong | Wrong meter map or parser. | Wrong key or parser. | Decoder not matching the payload. |
Common to all three
- The gateway, MBus master or receiver needs a working connection to the platform. For SIM based units such as the CMe2100, the Elvaco Edge and the ZENNER B.One Gateway, check the SIM and the mobile signal first when a whole site goes quiet. Only Ethernet based units such as the CMe3100 depend on a local network.
- Meters should be labelled and mapped. Without a schematic, fault finding takes many times longer. The hardwired MBus case study shows how much time good records save.
- Record the addresses, IDs and keys at commissioning and keep them where support can find them.
- Check the heat meter itself when the communications look healthy. See Quick Approach to Heat Meter Fault Finding.
Frequently asked questions
Which is better, wired MBus or wireless MBus?
Wired MBus is more reliable and powers the meters, but needs cable. Wireless MBus avoids cable and suits retrofits, but depends on radio range and batteries.
Is LoRaWAN better than wireless MBus?
They suit different jobs. LoRaWAN covers more meters per gateway and uses very little battery but reports less often. Wireless MBus reports more often over shorter distances.
Can I mix different communication methods on one site?
Yes. Many sites do. Each meter should be recorded with its method so that the right fault guide is used.
What should I check first when meters stop reporting?
Check how many are affected. One meter points to the meter or its position. Many meters point to the gateway, MBus master or receiver, or to its SIM or network connection.
Need a hand on site? Contact Sycous at info@sycous.com and have the details from the checklist above ready.