Technical Specifications
| Parameter Name | Parameter Value |
|---|---|
| Product Model | ALLEN-BRADLEY 1408-EM3A-ENT |
| Manufacturer | Allen-Bradley / Rockwell Automation |
| Product Type | Power and Energy Monitor (EM3 Full-Function Model) |
| Product Series | PowerMonitor 1000 / Bulletin 1408 |
| Communication Protocols | EtherNet/IP, Modbus TCP, Modbus RTU (Serial RS-485), DF1 |
| Ethernet Port | 10/100 Mbps, standard RJ-45 with status indicators |
| Serial Port | RS-485, three-pin connector |
| Input Voltage (3-Phase Nominal) | 600 V AC RMS |
| Input Voltage (1-Phase Nominal) | 347 V AC RMS |
| Input Current | 5 A rated secondary (via external CTs) |
| Input Frequency | 50/60 Hz |
| Accuracy Class | 1 (IEC 62053-21 for kWh), 1 (IEC 62053-23 for kVARh) |
| Control Power | 120–240 V AC, 50/60 Hz or 125–250 V DC |
| Operating Temperature | −10 °C to 60 °C (14 °F to 140 °F) |
| Storage Temperature | −40 °C to 85 °C (−40 °F to 185 °F) |
| Humidity | 5% to 95%, non-condensing |
| Vibration | 2.0 g, 10–500 Hz |
| Shock | 30 g peak each axis (operating) |
| Dielectric Withstand | 2500 V (control power, voltage inputs, current inputs) |
| Enclosure Rating | IP10 (open device, NEMA/UL 508) |
| Mounting | Panel or DIN rail |
| Weight | Approximately 0.45 kg |
Main Features and Advantages
The ALLEN-BRADLEY 1408-EM3A-ENT delivers the most comprehensive energy monitoring capability in the PowerMonitor 1000 family, combining revenue-accurate metering with advanced power quality analysis and seamless network integration.
Full-function measurement suite: The ALLEN-BRADLEY 1408-EM3A-ENT measures the complete set of power parameters including voltage, current, frequency, voltage unbalance, current unbalance, kW, kVAR, kVA, true power factor, kWh, kVARh, kVAh, kW demand, kVAR demand, kVA demand, projected demand values, and demand power factor. This comprehensive measurement set eliminates the need for multiple dedicated meters, providing a single source of truth for all electrical parameters within the monitored circuit.
Ethernet connectivity with integrated web server: The ALLEN-BRADLEY 1408-EM3A-ENT features a standard RJ-45 Ethernet port supporting EtherNet/IP, Modbus TCP, and an embedded HTML web page for configuration and data access. Technicians can view real-time data and configure parameters directly through a web browser without specialized software, while control systems can retrieve energy data via EtherNet/IP implicit messaging or Modbus TCP for integration into SCADA and energy management platforms.
Revenue meter accuracy: The ALLEN-BRADLEY 1408-EM3A-ENT meets revenue accuracy standards, with accuracy class 1 for kWh (IEC 62053-21) and kVARh (IEC 62053-23). This level of precision enables the module to serve as a billing-grade meter for sub-metering applications where accurate cost allocation between departments, processes, or tenants is required.
Advanced logging and time-of-use functionality: The ALLEN-BRADLEY 1408-EM3A-ENT includes energy logs, minimum/maximum logs, status logs, and load factor logging, along with Time of Use (On-Peak, Off-Peak) functionality for tracking energy consumption during different rate periods. These logging capabilities support load profiling, cost allocation, and energy optimization initiatives by providing historical data for analysis.
Comprehensive communication flexibility: Beyond the Ethernet port, the includes an RS-485 serial port supporting DF1 half-duplex slave, DF1 full-duplex, and Modbus RTU slave protocols, with autodetection capability to automatically switch between serial protocols based on received packet format. This dual-interface design ensures compatibility with legacy control systems while providing modern Ethernet connectivity.