M-Bus 100A Two-Module DIN-Rail Single-Phase MID Energy Meter: A Complete Guide to Precision, Connectivity, and Reliable Energy Management

Introduction

Accurate energy measurement is becoming increasingly important in residential buildings, commercial facilities, industrial sites, renewable-energy installations, electric vehicle charging systems, and utility-managed networks. As electricity prices rise and energy regulations become more demanding, users need more than a basic consumption counter. They need a compact instrument that can measure, record, communicate, and support informed decisions about energy use.

The M-Bus 100A two-module DIN-rail single-phase MID energy meter is designed for precisely this purpose. Based on the SDM230-Mbus platform, the meter combines direct measurement up to 100A, multi-function electrical monitoring, pulse outputs, M-Bus communication, a backlit LCD, bidirectional energy measurement, and MID approval in a compact 36 mm enclosure. It is suitable for applications where installation space is limited but dependable measurement and remote data collection are essential.

Unlike conventional single-function kWh meters, this device provides a broader view of an electrical installation. It can measure active energy, reactive energy, voltage, current, power, power factor, frequency, and demand-related values. This additional information helps facility operators understand not only how much energy is being consumed, but also how electrical equipment is performing.

The combination of direct 100A capacity, DIN-rail mounting, two pulse outputs, M-Bus communication, and compliance with European metering requirements gives this product a strong position among compact single-phase energy meters. It can reduce the need for external current transformers, simplify wiring, support centralized monitoring, and provide a dependable basis for energy billing or allocation.

Mbus 100A 2 Module Din Rail Single Phase MID Energy Meter

Product Overview

The SDM230-Mbus is a single-phase, two-wire energy meter intended for 1P2W electrical systems. It is rated for a nominal voltage of 230V and supports direct current measurement up to 100A. The meter is installed on a standard DIN rail and occupies two modules, with a total width of approximately 36 mm.

The two-module format is especially useful in distribution boards where every millimeter of space matters. Many installations require several meters for apartments, offices, retail units, solar circuits, auxiliary systems, or individual tenants. A narrow enclosure allows more measurement points to be installed in the same panel without requiring a larger cabinet.

The meter measures RMS values on a single-phase AC system with neutral connection. Its rated current is 10A, maximum current is 100A, minimum current is 0.5A, and starting current is 40mA. This range allows the device to register both low-load operating conditions and high-demand circuits while maintaining a practical direct-connected architecture.

In addition to its metering function, the unit operates as a multi-function electrical monitor. Depending on the measured parameter, users can view voltage, current, active power, reactive energy, power factor, frequency, and other information through the LCD interface or retrieve data through the communication system.

The SDM230-Mbus provides two pulse outputs for energy signaling and one M-Bus communication port. The pulse outputs can be assigned to imported and exported energy, making them useful for external counters, building automation equipment, data loggers, or energy management controllers. The M-Bus port allows the meter to be connected to a centralized reading system in which multiple meters share a communication network.

Key Technical Characteristics

Parameter	Specification
System type	Single-phase, two-wire AC system
Measurement method	RMS measurement
Nominal voltage	230V
Operational voltage	80% to 120% of nominal voltage
Rated current	10A
Maximum direct current	100A
Minimum current	0.5A
Starting current	40mA
Active energy accuracy	IEC 62053-21 Class 1.0 and EN 50470-1/3 Class B
Reactive energy accuracy	IEC 62053-23 Class 2 and IEC 61557-12 Class 2
Voltage accuracy	0.5% of range maximum
Current accuracy	0.5% of range maximum
Frequency accuracy	0.2% of mid-frequency
Power accuracy	1% of range maximum
Power factor accuracy	1% of unity, or 0.01
Communication	M-Bus according to EN 13757-3
M-Bus address range	1 to 250
M-Bus baud rate	300bps to 9600bps
Pulse outputs	Two outputs for imported and exported energy
Mounting	DIN rail
Width	Two modules, approximately 36mm

Direct 100A Measurement Without External Current Transformers

One of the most important advantages of this meter is its ability to measure loads up to 100A through direct connection. Many energy meters designed for higher-current circuits require external current transformers. Although current transformers are useful in large installations, they add cost, wiring complexity, panel space requirements, and additional points that must be checked during commissioning.

A direct-connected meter simplifies the measurement chain. The load conductors pass through the meter, allowing the instrument to measure current without a separate transformer assembly. For residential distribution boards, small commercial units, apartments, workshops, solar auxiliary circuits, and EV charging applications, this approach can significantly reduce installation time.

Eliminating external CTs also avoids several practical concerns. Installers do not need to select a transformer ratio, verify polarity markings, manage secondary wiring, or provide additional space for transformer terminals. The system has fewer components that can be incorrectly connected or damaged during maintenance.

Direct measurement can also make documentation easier. A project design based on one compact meter is generally simpler to describe than a design involving a meter, one or more CTs, secondary protection, and additional terminal connections. This is valuable for contractors working on repeated installations or large projects containing many individual metering points.

External CTs remain appropriate for circuits above the direct-measurement limit or for installations where conductors cannot be routed through the meter. However, within the 100A range, the direct-connected design offers an efficient alternative to transformer-based metering. It is one of the clearest ways in which this product can reduce total installation complexity compared with competing CT-dependent solutions.

Compact DIN-Rail Form Factor

Space efficiency is a major consideration in modern electrical panels. Distribution boards increasingly contain circuit protection, surge protection, contactors, timers, communication gateways, residual-current devices, and other control equipment. A wide energy meter may force the installer to use a larger enclosure or reorganize the entire panel layout.

The two-module, 36 mm form factor addresses this problem directly. The meter can be placed beside circuit breakers or other modular equipment on a standard DIN rail. Its compact design is useful for new installations and for retrofit projects where the existing panel has limited spare capacity.

A small enclosure does not mean that the meter is limited to a single reading. The product retains multi-function measurement, communication capability, pulse outputs, and a display while occupying only two modules. This balance between physical size and functionality is a major advantage over larger meters that provide similar data but consume substantially more cabinet space.

The compact design can also reduce enclosure material costs. When multiple meters are installed, the cumulative space saving may allow a smaller cabinet, shorter internal wiring routes, and more efficient use of mounting rails. For apartment sub-metering or multi-tenant commercial properties, these savings can become significant across an entire project.

Measurement Functions and Electrical Visibility

A basic kWh meter reports energy consumption, but a modern energy management system often needs additional electrical information. The SDM230-Mbus is designed as a multi-function meter, enabling users to monitor several operating variables through one instrument.

Active energy is the primary measurement for most billing and consumption-management tasks. The meter supports Class 1.0 active energy accuracy under IEC 62053-21 and Class B performance under EN 50470-1/3. These standards provide a recognized framework for evaluating energy measurement performance and support the product’s suitability for applications requiring dependable energy records.

Reactive energy measurement is valuable in installations containing motors, transformers, pumps, compressors, fluorescent lighting, and other inductive or power-electronic loads. The meter supports reactive energy measurement according to IEC 62053-23 Class 2 and IEC 61557-12 Class 2. Monitoring reactive energy can help engineers identify poor power-factor conditions and evaluate the effectiveness of correction equipment.

Voltage measurement helps users verify whether the supply is operating within the expected range. The meter is designed for a nominal 230V system and supports an operational range from 80% to 120% of nominal voltage. Observing voltage trends can help identify supply problems, overloaded circuits, loose connections, or equipment behavior associated with voltage variation.

Current measurement provides an indication of circuit loading. It can help technicians determine whether a circuit is approaching its design capacity, whether demand is balanced with expectations, or whether a particular load is drawing more current than anticipated.

Active power shows the instantaneous rate of energy use. This is useful for identifying startup behavior, peak demand, equipment cycling, and the effect of switching large loads on or off. Power-factor information adds another layer of analysis by showing how effectively electrical current is being converted into useful power.

Frequency measurement provides an additional indication of supply quality. In normal grid-connected operation, frequency is usually stable, but changes may be relevant in backup-power systems, generator installations, microgrids, and other applications where supply conditions must be monitored closely.

The inclusion of demand-related values can support load profiling and capacity planning. Facility managers can use demand information to understand when a circuit or building reaches its highest operating level, helping them evaluate tariffs, equipment schedules, and opportunities for load shifting.

Bidirectional Energy Measurement for Modern Power Systems

Electricity no longer flows in only one direction in many installations. Rooftop solar systems, battery storage, microgrids, and prosumer applications may consume energy from the grid at one moment and export energy back to it at another. A meter that records only imported energy cannot provide a complete picture of such systems.

The SDM230-Mbus supports bidirectional measurement. This means it can distinguish between energy entering the installation and energy leaving it, depending on the application and wiring arrangement. The capability is particularly useful for small solar photovoltaic systems, energy storage installations, and sites where local generation is connected to a single-phase distribution circuit.

Bidirectional measurement also supports more accurate energy allocation. A building operator may need to determine how much energy was imported from the utility, how much was generated locally, and how much surplus generation was exported. Recording both directions creates a more complete basis for analysis and settlement.

The two pulse outputs can further support this function by transmitting pulses associated with imported and exported energy. External controllers can count these pulses to create a simple real-time representation of energy flow, while the M-Bus connection can provide more comprehensive data to a central monitoring platform.

For solar and storage projects, the combination of direct 100A measurement, bidirectional recording, compact DIN-rail mounting, and communication capability can reduce the number of separate devices needed in the distribution board. This helps keep the installation organized while preserving access to key electrical data.

Reliable M-Bus Communication

M-Bus, standardized under the EN 13757 family, is widely used for meter reading and utility data collection. It is designed for networks in which multiple meters communicate with a central master device. The SDM230-Mbus uses M-Bus EN 13757-3 communication, making it suitable for integration into building energy management systems, remote reading platforms, and centralized metering applications.

The meter supports communication addresses from 1 to 250 and baud rates from 300bps to 9600bps. This gives system designers flexibility when configuring networks with different host devices and communication requirements. The maximum stated transmission distance is up to 1000 meters, although the practical distance depends on cable type, network topology, power conditions, installation environment, and the number of connected devices.

M-Bus communication reduces the need for personnel to visit each meter and manually record readings. Instead, a gateway or master controller can collect data from multiple meters and send it to software used for billing, reporting, maintenance, or energy analysis.

Centralized reading is especially valuable in multi-tenant buildings. A property manager can assign individual meters to apartments, offices, retail units, or technical areas. Data can then be organized by location or user, making it easier to calculate internal allocations and identify unusual consumption patterns.

In commercial and industrial environments, M-Bus data can be incorporated into broader building management systems. Energy information may be correlated with occupancy, operating schedules, production output, weather conditions, or equipment status. This creates a stronger foundation for energy-efficiency programs than isolated manual readings.

Compared with a meter that provides only a local display, the M-Bus version offers better scalability. A local display remains useful for inspection and commissioning, but remote communication allows the meter to become part of a coordinated measurement network. This combination of local accessibility and centralized data collection is a practical advantage over simpler competing products.

Communication Planning Considerations

Installers should plan the M-Bus network before commissioning. Each meter should receive a unique address, and the master device should be configured for a compatible baud rate, parity, and stop-bit arrangement. The specified default parity is none, while odd and even parity options are also supported. One or two stop bits can be selected according to the requirements of the host system.

Network cables should be routed away from sources of strong electromagnetic interference where practical. Long cable runs, large numbers of devices, and electrically noisy environments may require additional design attention. Correct polarity, secure terminal connections, and clear labeling help prevent communication faults during startup and future maintenance.

Pulse Outputs for Flexible Integration

Although M-Bus provides detailed digital communication, pulse outputs remain valuable because they are simple, widely supported, and easy to connect to external counters or controllers. The SDM230-Mbus provides two pulse outputs for imported and exported energy.

Pulse outputs can be connected to building automation systems, programmable logic controllers, remote counters, data acquisition equipment, or specialized energy-monitoring devices. They are useful when a project already has a pulse-counting infrastructure or when a simple energy signal is required without implementing a complete digital communication protocol.

The pulse interface can also provide redundancy. The M-Bus system may be used for detailed data collection, while pulse outputs provide a separate signal for a local controller or independent verification system. This can help project engineers compare readings or maintain basic monitoring if the communication network is temporarily unavailable.

For smaller installations, pulse outputs may be all that is needed. A controller can count pulses over time and calculate energy consumption, while the meter’s LCD remains available for direct inspection. This makes the product adaptable to both advanced and relatively simple energy-management architectures.

Clear LCD Display with Backlighting

Remote communication is valuable, but a local display remains essential during installation, testing, and maintenance. The SDM230-Mbus includes an LCD with backlighting, allowing technicians to inspect readings directly at the panel.

A backlit screen improves visibility in electrical cabinets, plant rooms, basements, corridors, and service areas where ambient lighting may be poor. During commissioning, an installer can verify voltage, current, energy direction, and other measurements without connecting a laptop or temporary monitoring instrument.

The display also supports faster fault finding. If a remote system reports unexpected data, a technician can compare the central reading with the value shown locally. This helps determine whether the issue is related to the meter, the communication network, the gateway, or the software configuration.

For users who do not need continuous remote monitoring, the LCD provides a straightforward way to check consumption and electrical conditions. The result is a product that supports both advanced automation and conventional on-site inspection.

MID Approval and Standards-Based Performance

Measurement equipment used for commercial allocation or billing-related purposes must provide an appropriate level of accuracy, traceability, and regulatory confidence. The meter is MID approved and designed to meet the requirements of European Union Directive 2014/32/EU.

MID approval is important because it demonstrates that the relevant meter design and performance have been evaluated within a recognized regulatory framework. For building owners, system integrators, installers, and energy service providers, this can simplify product selection for projects where measurement data may be used for financial allocation or formal reporting.

The stated active-energy performance conforms to IEC 62053-21 Class 1.0 and EN 50470-1/3 Class B. These classifications provide a useful basis for comparing the meter with products that have not been evaluated against the same standards. The meter also supports reactive-energy performance under relevant IEC and power-quality measurement standards.

Compliance should always be considered together with the specific legal requirements of the installation location and intended use. Certification does not eliminate the need for correct installation, suitable wiring, proper sealing where required, and compliance with local electrical regulations. Nevertheless, MID approval provides an important foundation for projects requiring dependable and recognized energy measurement.

Accuracy and Measurement Confidence

Accuracy is not simply a marketing feature; it affects billing, energy analysis, equipment evaluation, and investment decisions. Small errors can become significant when readings are accumulated across many meters or over long periods.

The product specifies power accuracy of 1% of range maximum, current accuracy of 0.5% of range maximum, voltage accuracy of 0.5% of range maximum, frequency accuracy of 0.2% of mid-frequency, and power-factor accuracy of 1% of unity or 0.01. These specifications provide users with a clear framework for understanding the expected performance of the instrument.

Real-world accuracy depends on several factors. Correct wiring, stable supply conditions, appropriate load levels, installation temperature, electromagnetic environment, and proper commissioning all influence measurement quality. The meter’s broad functionality is therefore most effective when supported by professional installation practices.

For multi-meter systems, consistent measurement performance is particularly valuable. When each tenant, department, circuit, or generation source is measured using instruments with defined accuracy, comparisons become more meaningful and internal allocation becomes easier to defend.

Applications Across Different Sectors

Residential Sub-Metering

In apartment buildings, student housing, serviced residences, and other multi-unit properties, the meter can be installed to monitor individual apartments or dedicated circuits. Its compact size allows many meters to be placed in centralized distribution boards, while M-Bus communication supports automated data collection.

The direct 100A capacity is suitable for many residential circuits without requiring current transformers. Bidirectional measurement can also support homes with rooftop solar systems. Property managers can use the data for consumption reporting, internal allocation, or energy-efficiency programs.

Commercial Buildings

Offices, shops, restaurants, clinics, and small commercial facilities often need to measure tenant spaces, lighting circuits, HVAC equipment, server rooms, or equipment with separate energy budgets. The meter’s multi-function capabilities help users identify both energy consumption and electrical operating conditions.

Its M-Bus interface makes it suitable for integration into building management systems. A central platform can collect data from multiple circuits and present it through dashboards or scheduled reports. The information can be used to compare tenant loads, identify unusual changes, and evaluate energy-saving measures.

Solar Photovoltaic Systems

Small solar installations frequently require measurement of both imported and exported energy. A bidirectional meter can monitor the flow between the local installation and the grid, helping operators understand self-consumption, surplus generation, and grid dependence.

The two pulse outputs may be used for external monitoring equipment, while M-Bus provides a more detailed connection to a data acquisition or energy management system. The meter’s compact design is helpful in solar distribution boards where space is often shared with protective and switching devices.

Electric Vehicle Charging

Electric vehicle charging points can create substantial loads and may need dedicated energy measurement. The meter can monitor a single-phase charging circuit up to 100A, subject to the electrical design and local regulations. Its active energy measurement can support usage reporting, while current and power readings help operators understand charging demand.

In shared residential or workplace charging environments, the meter can support internal cost allocation. M-Bus communication allows charging-related consumption to be sent to a central platform, where it can be combined with access control, scheduling, or billing software.

Industrial and Utility Auxiliary Circuits

Small industrial machines, pumps, control panels, compressors, lighting systems, and auxiliary services can benefit from individual measurement. The meter’s reactive-energy and power-factor data can help maintenance teams evaluate the electrical behavior of motors and other inductive loads.

Although larger industrial feeders may exceed the direct 100A rating, many branch circuits remain within its range. In these cases, the device offers a compact method of adding detailed measurement without installing a larger transformer-based instrument.

Energy Management and Efficiency Projects

Energy-efficiency projects require reliable baseline data. Before changing equipment or operating schedules, managers need to know how much energy is being used and when. After improvements are implemented, the same measurement points can show whether the expected savings have been achieved.

The meter’s combination of active energy, demand-related values, power, current, voltage, frequency, and power factor supports this process. Communication through M-Bus enables long-term data collection, while the display and pulse outputs provide convenient local and auxiliary access.

Advantages Over Basic and CT-Based Competitors

The market includes many single-phase meters, but products with similar nominal functions may differ considerably in installation requirements, communication options, certification, and physical design. The SDM230-Mbus has several practical advantages.

First, direct 100A measurement eliminates the need for external CTs in applications within the rated current range. This can reduce equipment cost and installation labor while lowering the risk of transformer-ratio or polarity errors.

Second, the two-module enclosure saves distribution-board space. A competing meter may offer similar data but occupy three or four modules, which can become a significant disadvantage in projects with many measurement points.

Third, the meter combines local display, two pulse outputs, bidirectional measurement, and M-Bus communication. Some low-cost products offer only a local kWh display, while others provide communication but no pulse outputs or no reverse-energy measurement. The broader combination makes this product more adaptable.

Fourth, MID approval and standards-based accuracy provide greater confidence for applications involving energy allocation or regulated measurement. Buyers can evaluate the product using recognized performance classes rather than relying only on general claims of accuracy.

Fifth, the meter is a multi-function instrument rather than a simple energy counter. Voltage, current, power, power factor, and frequency data can help users diagnose conditions and improve system management. This reduces the need for separate portable instruments or additional monitoring modules.

Finally, the product is supported by a manufacturer with experience in energy meters, power analyzers, current sensors, communication modules, and energy management systems. A broad product portfolio can help customers build a more consistent measurement architecture across different voltage levels, current ranges, and communication requirements.

Manufacturing and Engineering Strengths

Product performance depends not only on the published specification but also on the manufacturer’s engineering, testing, process control, and support capabilities. Eastron Electronic Co., Ltd. has developed its business around electricity measurement and energy management products, giving it experience across metering hardware, embedded software, communication technologies, and system integration.

The company operates professional laboratory capabilities for EMC, low-voltage directive, accuracy, and environmental testing. These testing areas are important for energy meters because the devices must operate reliably in real electrical environments while maintaining measurement performance.

Electromagnetic compatibility testing helps evaluate resistance to interference and the meter’s own emissions. This is particularly relevant in modern panels containing switching power supplies, variable-frequency drives, contactors, photovoltaic inverters, and communication equipment. A meter that has been assessed for EMC behavior is better positioned for dependable operation in complex installations.

Accuracy testing verifies measurement performance under controlled conditions and supports compliance with applicable IEC, EN, GB, and UL-related requirements where relevant. Environmental testing helps assess how the product responds to operating conditions such as temperature variation, humidity, and other stresses encountered in field installations.

The company’s ISO 9001 quality management system provides a structured framework for design control, purchasing, manufacturing, inspection, corrective action, and continual improvement. Quality management is particularly important for meters because a small production variation can affect large numbers of readings when products are deployed across a building or utility program.

Manufacturing approval and inspection associated with SGS and MID requirements further strengthen confidence in production consistency. For customers purchasing meters for large projects, controlled manufacturing processes help reduce variation between units and support more predictable commissioning.

Research and development is another important strength. The company maintains development teams in China and the United Kingdom and cooperates with universities and technical institutions. This combination of internal development and external cooperation supports continued work in embedded software, communications, measurement algorithms, hardware design, and energy-management applications.

Patented technologies in software, embedded software, and hardware indicate that the company invests in proprietary engineering rather than relying only on generic meter platforms. This can help improve product differentiation, long-term platform development, and adaptation to changing market requirements.

How Advanced Manufacturing Supports Product Reliability

Reliable energy measurement requires coordinated control of mechanical, electrical, firmware, and calibration processes. The enclosure must protect internal components and maintain secure connections. The current path must support the specified direct-load capacity. Measurement circuits must be calibrated consistently. Communication functions must operate correctly across the intended network range.

A professional manufacturing process typically begins with controlled component selection and supplier management. Components used in the current path, voltage sensing circuit, display, communication interface, and power supply must meet design requirements. Incoming inspection helps verify that materials and parts conform before they enter production.

Assembly control is equally important. Correct placement and soldering of components contribute to long-term stability. Terminal construction and mechanical fastening must support safe installation and repeated service operations. Automated and manual inspection stages can identify workmanship problems before products are packed.

Calibration and functional testing are central to meter production. Each unit must be evaluated against reference conditions so that the measurement system provides consistent results. Functional tests may include display operation, pulse output behavior, communication response, button or interface operation, and response to different current and voltage conditions.

Final quality control provides another opportunity to verify labeling, enclosure condition, terminal integrity, communication settings, and product configuration. Traceability records can help identify production batches and support after-sales service if a technical question arises.

The manufacturer’s laboratory capabilities support this process by providing facilities for more than routine production checks. EMC, accuracy, environmental, and electrical safety evaluations can be used during product development, design validation, and continuous improvement. This creates a feedback loop between engineering and manufacturing.

Installation and Commissioning Guidance

The meter should be installed by qualified personnel in accordance with applicable electrical regulations and the project’s wiring diagram. Before installation, the installer should verify the system type, voltage, current, phase arrangement, neutral connection, and expected load. The product is designed for a single-phase two-wire system and should not be connected to an incompatible configuration.

Because the meter supports direct current measurement up to 100A, the conductor size and protective equipment must be selected according to the installation design. The meter does not replace overcurrent protection or other required protective devices. Upstream protection, isolation, and safe access must be provided in accordance with local standards.

After mounting the meter on the DIN rail, the line and neutral conductors should be connected to the correct terminals. Terminal screws should be tightened to the manufacturer’s specified torque where provided. Incorrect polarity, loose terminals, or reversed wiring can affect measurement direction or create a safety hazard.

For systems with local generation, installers should pay particular attention to the intended import and export direction. The wiring arrangement should correspond to the project’s measurement objectives so that imported and exported energy are recorded correctly.

The M-Bus network should be configured after the power wiring has been checked. Each meter needs a suitable communication address, and the host system must use compatible communication parameters. A commissioning test should confirm that the central master can identify the meter, read energy values, and distinguish the relevant data registers.

Pulse outputs should be tested by comparing counted pulses with the meter’s energy display or communication data. This confirms that the external controller is receiving the expected signal and that the pulse assignment is understood correctly.

During commissioning, technicians should record the meter serial number, address, installation location, initial energy reading, wiring arrangement, and communication settings. This information simplifies future maintenance and supports accurate project documentation.

Maintenance and Long-Term Operation

Electronic meters generally require less routine maintenance than mechanical measuring equipment, but periodic verification remains good practice. Operators should inspect the enclosure, terminal condition, display, communication status, and reported values during scheduled electrical maintenance.

Unexpected changes in current, voltage, power factor, or energy consumption may indicate a load change, equipment fault, wiring problem, communication issue, or data configuration error. Comparing local display readings with centralized data can help identify the source of the problem.

Communication networks should be reviewed when meters are added, removed, or replaced. Duplicate addresses, damaged cables, altered baud rates, and incorrect gateway settings can prevent successful data collection even when the meter itself is operating normally.

Where meters are used for formal billing or cost allocation, the operator should maintain records of installation, configuration, inspection, and any verification activity. The applicable legal and regulatory requirements should determine whether periodic testing, sealing, or official verification is required.

Value for System Integrators and Project Designers

System integrators benefit from products that combine several functions in one standardized platform. The SDM230-Mbus can serve as a repeatable building block in projects containing multiple single-phase circuits. Its common form factor, communication approach, and measurement capabilities simplify the development of standard panel designs.

Project designers can specify the meter for residential, commercial, solar, EV, or auxiliary circuits while retaining a consistent approach to data collection. This reduces the number of different meter types that must be documented, installed, commissioned, and supported.

The device also supports phased project development. A small installation may begin with local display readings and pulse outputs. Later, an M-Bus master and software platform can be added to centralize data without replacing the meters. This ability to expand monitoring over time can be valuable when budget or project complexity changes.

For equipment manufacturers and panel builders, the compact enclosure helps optimize cabinet layouts. A two-module device can be incorporated into modular boards alongside protective, switching, and communication equipment. Standardized labeling and wiring procedures can improve production efficiency when many panels are assembled.

Selection Considerations

Before selecting this meter, users should confirm that the electrical system is single-phase, two-wire and that the expected maximum current does not exceed 100A. Applications outside these conditions may require a different meter, a transformer-operated model, or a three-phase instrument.

Users should also determine whether M-Bus is the preferred communication method. M-Bus is well suited to centralized meter reading, while other applications may require RS485 Modbus, wireless communication, LoRaWAN, or another protocol. The SDM230 product family includes alternative versions with different communication and input-output configurations, but the specific model should match the project requirements.

The intended use of the data should be considered carefully. If measurements are used only for monitoring, a standard energy meter may be sufficient. If readings support formal energy allocation or regulated billing, MID approval, installation conditions, local legal requirements, and verification procedures must all be reviewed.

Finally, the installation environment should be evaluated. Temperature, humidity, electromagnetic interference, enclosure protection, access, and available panel space can all affect product selection and system reliability.

Q&A

What type of electrical system does the meter measure?

The meter is designed for a single-phase, two-wire AC system, commonly described as 1P2W. It is intended for a nominal voltage of 230V and measures RMS values on a single-phase installation.

What is the maximum current rating?

The meter supports direct load measurement up to 100A. Its rated current is 10A, minimum current is 0.5A, and starting current is 40mA.

Are external current transformers required?

No external current transformer is required for direct measurement within the product’s 100A maximum current rating. This simplifies installation and saves panel space. Circuits above 100A may require a different transformer-operated meter.

What communication protocol does the product use?

The SDM230-Mbus uses M-Bus communication according to EN 13757-3. It supports addresses from 1 to 250 and baud rates from 300bps to 9600bps.

Does the meter support remote reading?

Yes. The M-Bus interface allows the meter to communicate with a central master, gateway, building management system, or energy data platform. This enables remote reading and centralized data collection.

Does it measure exported energy as well as imported energy?

Yes. The meter supports bidirectional measurement and provides two pulse outputs for imported and exported energy. This makes it suitable for applications involving solar generation, battery systems, and other installations with two-way energy flow.

What information can be measured?

The meter can measure active energy, reactive energy, voltage, current, power, power factor, frequency, and demand-related values. The exact data available through the display or communication system depends on the product configuration and register arrangement.

Is the meter suitable for solar photovoltaic systems?

Yes. Its bidirectional measurement, direct 100A capacity, pulse outputs, compact DIN-rail design, and M-Bus communication make it suitable for many single-phase solar applications. The electrical design must confirm that the system remains within the meter’s voltage and current specifications.

Can it be used for EV charging measurement?

It can be used to measure suitable single-phase EV charging circuits up to 100A, provided that the installation complies with applicable electrical and charging regulations. M-Bus communication can support centralized charging-energy records and internal allocation.

What does MID approval mean?

MID approval indicates that the meter has been assessed against relevant requirements of European Union Directive 2014/32/EU. It supports use in applications where recognized measurement performance is important, subject to local legal requirements and correct installation.

How wide is the meter?

The meter occupies two DIN modules and has an approximate width of 36 mm. This compact size helps conserve space in distribution boards and control cabinets.

What are the pulse outputs used for?

The two pulse outputs can provide energy pulses to external counters, controllers, data loggers, building automation systems, or monitoring equipment. They can be used for imported and exported energy signals.

Does the meter have a local display?

Yes. It includes a backlit LCD display. The display allows technicians and operators to inspect electrical values locally during operation, installation, and maintenance.

What should be checked before installation?

The installer should verify the system type, voltage, current, neutral connection, wiring diagram, protective equipment, DIN-rail space, communication requirements, and local regulatory conditions. Correct wiring and commissioning are essential for safe and accurate operation.

What manufacturing capabilities support the product?

The manufacturer maintains professional testing capabilities for EMC, low-voltage, accuracy, and environmental evaluation. It also operates under an ISO 9001 quality management system and has research and development capabilities in China and the United Kingdom.

Conclusion

The M-Bus 100A two-module DIN-rail single-phase MID energy meter provides a balanced combination of compact construction, direct high-current measurement, multi-function monitoring, bidirectional energy recording, local display, pulse outputs, and centralized communication. These features make it suitable for a broad range of modern energy applications.

Its direct 100A design can eliminate external current transformers in many installations, reducing component count and simplifying commissioning. Its 36 mm width helps preserve valuable distribution-board space. Its M-Bus interface supports centralized reading, while the two pulse outputs provide an additional and flexible connection method.

The meter is more than a basic kWh counter. By measuring voltage, current, power, frequency, power factor, reactive energy, and other values, it gives users greater visibility into electrical performance. Bidirectional measurement extends its usefulness to solar generation, battery storage, EV charging, and other systems in which energy can flow in both directions.

MID approval and standards-based accuracy support applications that require dependable and recognized measurement. Behind the product, the manufacturer’s laboratory facilities, quality management system, research and development teams, testing capabilities, and broad energy-measurement portfolio provide important support for long-term product development and customer service.

For system designers, installers, property managers, energy consultants, and facility operators, the product offers a practical way to create scalable single-phase metering systems. It can function as a standalone local meter, a pulse-based monitoring device, or a component in a larger M-Bus energy-management network. This flexibility, combined with compact installation and direct 100A measurement, makes it a strong option for efficient and reliable energy monitoring.

References

1. IEC 62053-21, Electricity Metering Equipment: Particular Requirements for Static Meters for Active Energy.

2. IEC 62053-23, Electricity Metering Equipment: Particular Requirements for Static Meters for Reactive Energy.

3. EN 50470-1, Electricity Metering Equipment: General Requirements, Tests, and Test Conditions.

4. EN 50470-3, Electricity Metering Equipment: Static Meters for Active Energy.

5. EN 13757-3, Communication Systems for Meters and Remote Reading of Meters: Application Protocols.

6. IEC 61557-12, Electrical Safety in Low-Voltage Distribution Systems: Power Metering and Monitoring Devices.

7. European Union Directive 2014/32/EU on Measuring Instruments.

8. ISO 9001, Quality Management Systems: Requirements.

9. Manufacturer technical information for the SDM230-Mbus single-phase multifunction energy meter.

Product: Mbus 100A 2 Module Din Rail Single Phase MID Energy Meter