APM521 Multifunction Power Meter

In scenarios such as industrial automation, building power distribution, data centers, and renewable energy grid integration, precise measurement, stable monitoring, and efficient management of power data are the cornerstone of ensuring supply safety, improving energy efficiency, and reducing operational costs.

Acrel Electric, with decades of expertise in power instrumentation, proudly introduces the APM521 Network Power Meter. Engineered to IEC international standards, it integrates comprehensive electrical measurement, energy statistics, power quality analysis, event recording, and network communication into a single device — delivering a one-stop solution for grid power quality monitoring and serving as the intelligent nerve ending of modern power systems.

1. Comprehensive Measurement — Full-Spectrum Power Parameter Coverage

The APM521 transcends the limitations of conventional meters, enabling one-stop, high-precision acquisition of electrical parameters.

• From fundamental parameters — three-phase voltage, current, power, and frequency

• to advanced energy analytics — including four-quadrant energy, per-phase energy, multi-tariff energy, and frozen energy data,

• and further to deep power quality analysis covering voltage/current unbalance, 2nd–63rd order harmonics, total harmonic distortion, and voltage crest factor

• every reading is accurate and dependable. 

With a measurement accuracy of ±0.2% and active energy metering reaching 0.2S class precision, it satisfies the most demanding industrial metering and compliance requirements.

Additionally, the meter supports real-time and maximum demand statistics for three-phase current and power, complete with timestamp recording to precisely capture consumption peaks. The extreme-value function automatically logs monthly and previous-month parameter extremes, providing comprehensive data support for usage analysis and fault root-cause investigation — making every kilowatt-hour fully traceable.

2. Stable & Reliable — Built for Harsh Environments

The reliability of a power meter is directly tied to the safety of the entire electrical system.

The APM521 has passed a battery of rigorous tests, delivering industrial-grade robustness. Its auxiliary power supply accepts a wide input range of AC/DC 85–300V with power consumption as low as 4W, adapting to diverse supply conditions. Electromagnetic compatibility reaches Class IV for electrostatic discharge, electrical fast transients, and surge immunity. With power-frequency withstand voltage of AC 4kV and insulation resistance exceeding 500 MΩ, it operates reliably even in electrically noisy industrial environments.

• Operating temperature spans –40 °C to +70 °C; 

• Relative humidity up to 95% non-condensing;

• Functions normally at altitudes up to 5000 m.

• Protection rating: IP54 front panel, IP30 rear housing.

Whether deployed in high-temperature workshops, humid basements, or remote high-altitude stations, it delivers dependable 24/7 performance against the harshest conditions.

3. Flexible Expansion — Adaptable to Diverse Application Scenarios

Designed for the unique requirements of different industries.

The APM521 features a highly flexible modular design, supporting both panel-mount and DIN-rail installation. With standard cutout dimensions and straightforward mounting, it fits seamlessly into dense switchgear arrays as well as distributed point deployments.

Rich optional functions include:

• 4 digital inputs + 2 digital outputs for real-time switch status monitoring and interlock control;

• 2 channels of 4–20 mA analog output for easy integration with PLC and DCS systems; 

• Dual RS485 and Ethernet communication expansion, supporting Modbus-RTU, Modbus-TCP, and DL/T 645-2007 protocols, compatible with a wide range of SCADA and monitoring platforms;

• Micro SD card scheduled data storage for massive historical records, retained even after power loss, meeting long-term data traceability needs.

4. Intuitive Operation — Smart Management Made Simple

The APM521 features a human-centered interface designed for ease of use.

The high-resolution display clearly presents overview, electrical parameters, energy, harmonics, and more. Navigation keys — Menu, Esc, Enter, and adjustment buttons — follow a logical flow, enabling rapid operation without specialized training.

Parameter configuration is flexible and comprehensive, supporting customization of over 100 settings including wiring mode, CT/PT ratios, communication address, alarm thresholds, tariff schedules, and demand cycles. Default password is 0001, modifiable for enhanced security. The alarm system covers dozens of conditions — over-voltage, under-voltage, over-current, unbalance, harmonics, and more — with digital output relay action for instant anomaly notification, helping prevent electrical risks proactively.

Intelligent management features include time synchronization, auto-reset of extreme values, and factory reset. Paired with PC software, the meter enables remote monitoring, batch configuration, and data export — significantly reducing maintenance workload and enabling truly smart, efficient power management.

5. Wide-Ranging Applications — Empowering Power Upgrades Across Industries

With its all-in-one functionality, dependable performance, and flexible adaptability.

The APM521 multifunction meter is widely deployed across industrial plants, commercial buildings, data centers, rail transit, solar & wind power, municipal distribution, and beyond:

• Industrial Sector: Real-time production line power monitoring and power quality analysis, preventing harmonic interference with sensitive equipment.

• Renewable Grid Integration: Monitoring solar and wind grid-tie parameters to ensure compliance with grid code requirements.

• Data Centers: 7×24 power system surveillance with anomaly alarms, safeguarding uninterrupted equipment operation.

Choose Acrel APM521 — Elevate Your Power Monitoring Experience

From precision measurement to intelligent management, from rock-solid reliability to flexible expansion — the Acrel APM521 Network Power Meter redefines what a multifunction power meter can be, with core advantages of full functionality, high accuracy, exceptional reliability, and effortless operation.