≤75 ms Communication Refresh
Specified RS485 communication refresh time of ≤75 ms for applications requiring timely meter-side data updates.
DEM3A202 100 A Three-Phase DIN-Rail Energy Meter with RS485
DEM3A202 is a compact 3P DIN-rail, direct-connected three-phase energy meter for connected AC energy monitoring and system integration. Rated up to 100 A, it supports two-way RS485 communication compatible with Modbus RTU and DL/T 645-2007, with a specified communication refresh time of ≤75 ms. It also supports switched tariff operation and multiple energy-calculation modes.
Direct connection
3P3W (Delta) / 3P4W
MID Certified
MID
120/208–230/400 V 3-phase rated voltage
100 A Maximum current (Imax)
54 mm DIN-rail width
-40°C to +70°C Operating temperature
Product Highlights
Fast Data Refresh for three-phase direct metering
Class 0.5 Active Energy Accuracy
Class 0.5 active-energy measurement supports reliable monitoring and submetering applications.
RS485 with Dual Protocol
Supports two-way RS485 communication compatible with Modbus RTU and DL/T 645-2007 for integration with compatible monitoring systems.
Switched Tariff Input
Supports switched tariff input for dual-tariff applications. DEM3A202 has no internal battery, RTC or TOU schedule.
Flexible Energy Calculation
Supports forward, reverse, absolute-value, algebraic-sum and net-energy calculation modes for flexible submetering applications.
Display, Alarms and Diagnostics
LCD display, pulse LED, EEP diagnostics and configurable monitoring alarms support daily operation.
Applications
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Explore ApplicationTechnical Specifications
Technical Specifications
| Connection type | Direct connection |
| Wire system | 3P3W (Delta) / 3P4W |
| Rated voltage (Un) | 3 x 120/208 V to 3 x 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 | ±1 % |
| Active energy accuracy | Class 0.5 |
| Reactive energy accuracy | Class 1 |
| Communication method | RS485 |
| Communication type | Two-way |
| Supported protocols | Modbus RTU and DL/T 645-2007 |
| Communication address | 1–247 |
| Baud rate | 9.6 / 19.2 / 38.4 / 57.6 / 115.2 kbps |
| Parity | None / odd / even |
| Specified communication refresh time | ≤75 ms |
| Display and controls | Backlit LCD, 500 ms refresh, page-turning 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 | External switched tariff input; default two-tariff configuration. |
| Diagnostics and alarms | EEP self-diagnostics and configurable electrical-value alarms. |
| Other functions | Local firmware upgrade, wiring check, screen saver and runtime-hour counter. |
| Operating temperature | -40°C to +70°C |
| Ingress protection | IP20; use an IP54 outdoor or IP51 indoor enclosure. |
| Overvoltage category | OVC III |
| Protection class | Class II |
| Rated impulse withstand voltage | 6 kV |
Structure & Dimensions
DEM3A202 Dimensions & Wiring
Dimensions
Wiring
FAQ
Product FAQ
What is DEM3A202?
DEM3A202 is a 3P DIN-rail, direct-connected 3P3W (Delta) / 3P4W energy meter rated up to 100 A. It supports RS485 with Modbus RTU and DL/T 645-2007, with a specified communication refresh time of ≤75 ms. It supports switched tariff operation.
What connection and wire system does DEM3A202 use?
DEM3A202 uses direct connection with 3P3W (Delta) / 3P4W wiring.
What is the maximum current of DEM3A202?
The maximum current (Imax) is 100 A.
What is the pulse constant of DEM3A202?
The pulse constant is 1000 imp/kWh.
What interface or output does DEM3A202 provide?
It supports two-way RS485 communication compatible with Modbus RTU and DL/T 645-2007.
What is the active energy accuracy?
The active energy accuracy is Class 0.5.
What is the MID status of DEM3A202?
MID Certified. Display this status only when the certificate-verification page confirms the exact model/variant scope and current validity.
Product Downloads
Product Datasheet Download
Datasheet
DEM3A Series Product Datasheet
Official DEM3A 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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