M-Bus System Integration
Supports two-way M-Bus communication in accordance with EN 13757-3 for compatible monitoring systems.
DEM3A304 100 A Three-Phase DIN-Rail Energy Meter with M-Bus and TOU
DEM3A304 is a 3P DIN-rail, direct-connected 3P3W (Delta) / 3P4W energy meter rated up to 100 A. It supports two-way M-Bus communication in accordance with EN 13757-3 for compatible monitoring systems, four TOU tariffs with RTC scheduling plus external tariff switching, and flexible energy calculation. The meter includes an internal battery for RTC timekeeping.
Direct connection
3P3W (Delta) / 3P4W
120/208–230/400 V 3-phase rated voltage
100 A Maximum current (Imax)
54 mm DIN-rail width (3 modules)
−40°C to +70°C Operating temperature
Product Highlights
M-Bus three-phase tariff metering
Class 0.5 Active Energy Accuracy
Class 0.5 (Class C) active-energy measurement in accordance with IEC 62053-21 supports reliable energy monitoring and submetering applications.
M-Bus Configuration
Supports model-specific M-Bus addressing (1 to 250), selectable baud rates from 300 to 9600 bps and configurable communication settings for compatible monitoring systems.
TOU Tariffs and Multi-Tariff Support
Supports four internal TOU tariffs with RTC scheduling plus external tariff switching. Includes an internal battery for RTC timekeeping.
Flexible Energy Calculation
Supports forward, reverse, absolute-value, algebraic-sum and net-energy calculation modes for flexible submetering applications.
Internal Battery and RTC Timekeeping
Includes an internal battery for RTC timekeeping, enabling four TOU tariffs with time-scheduled switching.
Applications
Applications and Selection Guidance
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Explore ApplicationTechnical Specifications
Technical Specifications
| Connection type | Direct connection |
| Wire system | 3P3W (Delta) / 3P4W |
| Rated voltage (Un) | 3 × 120/208–230/400 V |
| Voltage tolerance | 0.8 to 1.15 Un |
| Frequency | 50/60 Hz |
| Current connection | Direct connection |
| Basic current (Ib) | 5 A |
| Minimum current (Imin) | 0.15 A (MID) / 0.25 A (IEC) |
| Maximum current (Imax) | 100 A |
| Power consumption | ≤2 W / 10 VA |
| Pulse constant | 1000 imp/kWh |
| Voltage accuracy | ±0.5 % |
| Current accuracy | ±0.5 % |
| Frequency accuracy | ±0.5 % |
| Active power accuracy | ±0.5 % |
| Reactive power accuracy | ±0.5 % |
| Active energy accuracy | Class 0.5 |
| Reactive energy accuracy | Class 1 |
| Communication interface | M-Bus |
| Protocol | M-Bus protocol (EN 13757-3) |
| Communication type | Bidirectional |
| Communication address | 1 to 250 |
| Baud rate | 300 / 600 / 1200 / 2400 / 4800 / 9600 bps |
| Data format | 7 data bits / 1 stop bit / even parity |
| Display and controls | Backlit LCD, 500 ms refresh, page navigation and setting buttons |
| LED indicator | Red pulse LED |
| Metering functions | Energy, power, power factor and harmonic monitoring |
| Energy calculation | Forward, reverse, absolute-value, algebraic-sum and net-energy modes |
| Tariff function | Four TOU tariffs with RTC scheduling plus external tariff switching; internal battery for timekeeping |
| Diagnostics and alarms | EEP self-diagnostics and configurable monitoring alarms |
| Other functions | Local firmware upgrade, wiring check, screen saver, page filter and runtime-hour counter |
| Operating temperature | −40°C to +70°C |
| Ingress protection | IP20; install in an IP54 outdoor or IP51 indoor enclosure |
| Overvoltage category | OVC III |
| Protection class | Class II |
| Rated impulse withstand voltage | 6 kV |
| Applicable standards | IEC 62052-11:2020 / IEC 62053-21:2020 / IEC 62053-24:2020 / EN 50470-3:2022 |
Structure & Dimensions
DEM3A304 Dimensions & Wiring
Dimensions
Wiring
FAQ
Product FAQ
What is DEM3A304?
DEM3A304 is a 3P DIN-rail, direct-connected 3P3W (Delta) / 3P4W energy meter rated up to 100 A. It supports two-way M-Bus communication for compatible monitoring systems, four-tariff metering and flexible energy calculation.
What connection and wire system does DEM3A304 use?
DEM3A304 uses direct connection with 3P3W (Delta) / 3P4W wiring.
What is the maximum current of DEM3A304?
The maximum current (Imax) is 100 A.
What interface or output does DEM3A304 provide?
It supports two-way M-Bus communication in accordance with EN 13757-3.
What is the active energy accuracy?
The active energy accuracy is Class 0.5 (Class C).
What metering modes are supported?
Forward, reverse, absolute-value, algebraic-sum and net-energy calculation modes.
Product Downloads
Product Datasheet Download
Datasheet
DEM3A M-Bus Series Product Datasheet
Official DEM3A M-Bus series datasheet covering product overview, specifications, wiring and dimensions.
Download PDF- Product overview and features
- Technical specifications
- Wiring diagrams and dimensions
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