Three-phase energy meter 5A class 0.5S MID Modbus PowerLogic A9MEM3255

Precise energy measurement in three-phase systems

The PowerLogic Acti9 iEM3000 series energy meter is a device designed for monitoring consumption in installations requiring high accuracy, especially where billing between different consumers or sub-assemblies is crucial. The device supports three-phase networks with a neutral conductor (3P+N) as well as 3P configurations, measuring both active and reactive energy. Thanks to the 0.5S accuracy class (according to IEC 62053-22) and MID (Measuring Instruments Directive) certification, it provides reliable data necessary for sub-billing. Current is measured indirectly – the device works with current transformers with a rated secondary current of 1 A or 5 A, allowing for safe measurement in high-current circuits.

Functionality and communication in modern installations

Modern energy management requires not only measurement but also easy access to data. This model is equipped with a Modbus RTU interface (via RS485 port), enabling integration with BMS systems, energy management software, or IoT platforms. Communication is carried out through screw terminals, which facilitates installation and reduces the risk of errors when connecting cables. The device supports four tariff schedules, providing flexibility in billing consumption across different time zones. Additionally, the meter features one programmable digital input and one digital output (which can function as a D0 pulse output). The number of pulses is adjustable in the range from 0 to 500 Imp/kWh (or kvarh), allowing the signal to be adapted to external recorders or alarm systems.

Construction, mounting, and status signaling

The device is characterized by compact dimensions: 90 mm width (corresponding to 5 DIN rail modules), 95 mm height, and 69 mm depth. Mounting is performed using a dedicated TH-35 type DIN rail adapter, guaranteeing stable fastening in modular distribution boards. On the front, there is a legible 9-digit LCD display that presents current operating parameters. Visual signaling is designed to provide key information about the device status at a glance: a green LED indicates the presence of power, while a flashing yellow LED allows for quick verification of correct operation and measurement accuracy. In the event that permissible values are exceeded, the installation is warned by an overload alarm, and a yellow communication LED signals Modbus port activity.

The device operates in a wide range of rated voltages: from 100 V to 277 V (between phase and neutral) and from 173 V to 480 V (between phases), at a mains frequency of 50 Hz or 60 Hz. The enclosure protection rating is IP20 (and the front panel IP40), which means it must be installed in protected electrical distribution boards. The meter has no anti-tamper or code lock, which simplifies its configuration for the installer while simultaneously meeting MID directive requirements for measuring instruments used in the commercial trade of electricity.