≤75 ms Communication Refresh
Specified RS485 communication refresh time of ≤75 ms for applications requiring timely meter-side data updates.
DEM3K302 6 A Three-Phase CT-Operated DIN-Rail Energy Meter with RS485 and TOU
DEM3K302 is a 3P DIN-rail, CT/PT-operated 3P3W (Aron) / 3P4W energy meter designed for high-precision energy monitoring through external current and voltage transformers. It supports RS485 communication with Modbus RTU and DL/T 645-2007 compatibility, a specified communication refresh time of ≤75 ms, four TOU tariffs with RTC scheduling plus external tariff switching, and Class 0.5s active energy accuracy. CT ratios up to 2000:1 and PT ratios up to 350:1 are supported.
CT/PT operated
3P3W (Aron) / 3P4W
MID Certified
MID
54 mm DIN-rail width (3 modules)
5(6) A CT input rating
2000:1 / 350:1 CT / PT max ratio
−40°C to +70°C Operating temperature
Product Highlights
Fast Data Refresh for CT-operated metering
Class 0.5s Active Energy Accuracy
Class 0.5s active-energy measurement in accordance with IEC 62053-21 supports high-precision energy monitoring through external CT/PT.
RS485 with Dual Protocol
Supports RS485 communication with Modbus RTU and DL/T 645-2007 compatibility, with configurable baud rates from 9.6 to 115.2 kbps and addresses from 1 to 247.
Flexible CT/PT Ratio Configuration
CT ratio up to 2000:1 and PT ratio up to 350:1. Maximum combined CT × PT ratio of 350000:1 supports a wide range of transformer configurations.
RTC-Based TOU and Tariff Switching
Uses battery-backed RTC timekeeping to support four TOU tariffs across eight time periods by default, together with external dual-tariff switching.
Multiple Energy Calculation Modes
Supports forward, reverse, absolute-value, algebraic-sum and forward/reverse offset energy calculation modes for different metering requirements.
Applications
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Explore ApplicationTechnical Specifications
Technical Specifications
| Connection type | CT / PT (external current and voltage transformers) |
| Wire system | 3P3W (Aron) / 3P4W |
| Rated voltage (Un) | 3 × 57.7/100–230/400 V (3P4W); 3 × 100–400 V (3P3W) |
| Voltage tolerance | 0.8 to 1.15 Un |
| Frequency | 50/60 Hz |
| Current connection | CT (external current transformer) |
| Basic current (Ib) | 5 A |
| Minimum current (Imin) | 0.05 A |
| Maximum current (Imax) | 6 A |
| CT ratio | Up to 2000:1 |
| PT ratio | Up to 350:1 |
| CT × PT ratio (max) | 350000:1 |
| Power consumption | ≤2 W / 10 VA |
| Pulse constant | 10000 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 0.5s |
| Reactive energy accuracy | Class 1 |
| Communication interface | RS485 |
| Protocol | Modbus RTU and DL/T 645-2007 |
| Communication type | Bidirectional |
| Communication address | 1 to 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 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 / EN 50470-3:2022 |
Structure & Dimensions
DEM3K302 Dimensions & Wiring
Dimensions
Wiring
FAQ
Product FAQ
What is DEM3K302?
DEM3K302 is a 3P DIN-rail, CT-operated 3P3W (Aron) / 3P4W energy meter rated up to 6 A. It supports RS485 with Modbus RTU and DL/T 645-2007, with a specified communication refresh time of ≤75 ms. Battery-backed RTC and TOU tariff functions are included.
What connection and wire system does DEM3K302 use?
DEM3K302 uses ct / pt voltage connection with 3P3W (Aron) / 3P4W wiring.
What is the maximum current of DEM3K302?
The maximum current (Imax) is 6 A.
What interface or output does DEM3K302 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 0.5S.
What tariff functions does DEM3K302 provide?
Four TOU tariffs with RTC scheduling plus external tariff switching. Internal battery for timekeeping.
Product Downloads
Product Datasheet Download
Datasheet
DEM3K Series Product Datasheet
Official DEM3K 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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