≤75 ms Communication Refresh
Specified RS485 communication refresh time of ≤75 ms for applications requiring timely meter-side data updates.
DEM1E302 45 A Single-Phase DIN-Rail Energy Meter with RS485 and TOU
DEM1E302 is a compact, single-phase, direct-connected DIN-rail energy meter for 1P2W systems, rated up to 45 A. It supports RS485 communication via Modbus RTU and DL/T 645-2007, with a specified RS485 communication refresh time of ≤75 ms. Battery-backed RTC, four TOU tariffs across eight time periods, and external tariff switching support time-based energy monitoring. DEM1E302 is suitable for AC-side monitoring in solar PV and BESS systems, AC EV charging, building submetering and industrial energy management.
DIN-Rail Mounting (1P (18 mm))
1P2W Direct Connection
MID B+D Certified
MID
45A Maximum current (Imax)
120–230 V Rated voltage
Class 0.5 Active energy accuracy
-40°C to +70°C Operating temperature
Product Highlights
Compact RS485 Metering with Fast Data Refresh and TOU
Class 0.5 Active Energy Accuracy
Class 0.5 active-energy measurement in accordance with IEC 62053-21 and Class 1 reactive-energy measurement in accordance with IEC 62053-23.
RS485 Dual Protocol Communication
RS485 communication compatible with Modbus RTU and DL/T 645-2007 protocols, with configurable baud rates from 9.6 to 115.2 kbps and addresses from 1 to 247.
Flexible Energy Calculation
Supports forward, reverse, forward, reverse, absolute-value, algebraic-sum and forward/reverse offset calculation modes
Full-Parameter Measurement
Measures voltage, current, frequency, active and reactive power, power factor and energy, and calculates current and voltage harmonic content.
Self-Diagnosis and Configurable Alarms
Provides EEP self-diagnosis and configurable alarms for monitored variables, with adjustable activation thresholds and delays.
Applications
Applications and Selection Guidance
EV Charging Metering
Solutions for AC/DC charging, billing and charging platform integration.
Explore ApplicationSolar PV & ESS Metering
DC/PV monitoring for inverters, storage systems and distributed energy monitoring.
Explore ApplicationC&I Sub-Metering
Branch metering for buildings, factories, tenants and energy allocation.
Explore ApplicationData Center Energy Metering
Rack, cabinet and distribution power monitoring for data center operations.
Explore ApplicationTechnical Specifications
Technical Specifications
| Wiring system | Direct connection, 1P2W |
| Rated voltage | 120-230V |
| Voltage tolerance | 0.8 to 1.15 Un |
| Frequency | 50/60Hz |
| Current connection | Direct connected |
| Basic current (Ib) | 5A |
| Minimum current (Imin) | 0.15A (MID) / 0.25A (IEC) |
| Maximum current (Imax) | 45A |
| Pulse constant | 1000 imp/kWh |
| Power consumption | <=2W / 10VA |
| Rated impulse withstand voltage | 6 kV |
| 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 interface | RS485 |
| Communication direction | Bidirectional |
| Protocols | Modbus RTU; DL/T 645-2007 |
| Modbus address | 1-247 |
| Baud rate | 9.6 / 19.2 / 38.4 / 57.6 / 115.2 kbps |
| Parity | None / Odd / Even |
| Refresh time | ≤75 ms |
| Display | Backlit LCD with automatic display cycling |
| Default display cycle | 5 seconds |
| LCD refresh time | 500 ms |
| LED | Red pulse LED |
| Buttons | Page turning and setting |
| Ingress protection | IP20 |
| Overvoltage category | OVC III |
| Protection class | Class II |
| Installation | 1P DIN rail |
| Operating temperature | -40°C to +70°C |
| Storage / transport temperature | -40°C to +70°C |
| Reference temperature | 25 ± 2°C |
| Relative humidity | ≤95%, non-condensing |
| Altitude | ≤2,000 m |
| Housing dimensions | 18 mm × 94 mm × 62.4 mm |
| Applicable standards | IEC 62052-11:2020 / IEC 62053-21:2020 / IEC 62053-24:2020 / EN 50470-3:2022 |
Structure & Dimensions
DEM1E302 Dimensions & Wiring
Dimensions
Wiring
FAQ
DEM1E302 FAQ
What communication protocols does DEM1E302 support?
DEM1E302 supports RS485 communication with Modbus RTU and DL/T 645-2007 compatibility. Confirm the required register list, baud rate and system settings before deployment.
What does the ≤75 ms specification refer to?
The current product specification lists a communication refresh time of ≤75 ms for the RS485 communication function. Actual end-to-end system performance also depends on controller polling, network configuration and system architecture.
Does DEM1E302 support RTC and TOU tariffs?
Yes. DEM1E302 supports RTC and TOU tariff functions, with four tariffs and eight time periods as the default configuration.
What is the difference between DEM1E302 and DEM1E202?
Both models support 45A direct connection, RS485 communication, Modbus RTU, DL/T 645-2007 and ≤75 ms communication refresh. DEM1E302 adds battery-backed RTC and TOU tariff functions, while DEM1E202 is the no-battery version with tariff switching only.
Does DEM1E302 support SO pulse output?
No. DEM1E302 is an RS485 communication version. The SO pulse-output version in this series is DEM1E001.
Can DEM1E302 measure forward and reverse energy?
Yes. The meter supports multiple energy-calculation modes, including forward and reverse energy measurement, absolute-value calculation and algebraic energy calculation.
Is DEM1E302 suitable for solar PV, BESS and EV charging projects?
It can be evaluated for AC-side solar PV, BESS, AC EV charging, building submetering and industrial energy-monitoring applications. Confirm wiring, current, communication and market requirements before selection.
How can I obtain the datasheet or certification documents?
Submit your project requirements and target market. Our team will confirm the applicable document version and provide the appropriate technical materials.
Product Downloads
Product Datasheet Download
Datasheet
DEM1E Series Product Datasheet
Official DEM1E series datasheet covering product overview, specifications, wiring and dimensions
Download Datasheet- Product overview and features
- Technical specifications
- Wiring diagrams and dimensions
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