4G Wireless Energy Meter for 3-Phase Solar PV Grid-Tied Monitoring: A Cost-Effective Bidirectional Solution Without Gateway
Introduction
Accurate bidirectional energy metering at the grid interconnection point is essential for small commercial PV systems operating without DC storage. Conventional solutions rely on wired RS485 installations or separate IoT gateways, adding cost and failure points. The ADW300-4GHW4G Wireless Power Meter directly addresses these challenges with an integrated cellular module, enabling three-phase photovoltaic grid connection monitoring and photovoltaic surplus power feedback metering without external hardware. This article outlines the technical architecture, application benefits, and comparative economics.
Key Takeaways:
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Built‑in 4G eliminates gateway hardware and reduces installation labor.
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Two-way metering energy meter registers forward (grid consumption) and reverse (PV export) active energy.
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Direct cloud upload via MQTT/Modbus‑TCP with zero local data infrastructure.
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3‑month free trial of Acrel Iot Platform for validation.
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Technical Core
The ADW300‑4GHW is a three‑phase wireless meter rated at 3×380–456V L‑L (or 3×660V L‑L) with a basic current input of 3×1(6)A, paired with external split‑core CTs. The AKH‑0.66/K K‑24 150/5 transformers (φ24mm aperture, Class 1.0) enable live retrofitting without disconnecting conductors.
Bidirectional energy registration is achieved through continuous sampling of voltage and current phase angles:
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EPI (Forward Active Energy) – grid‑to‑load flow (positive active power).
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EPE (Backward Active Energy) – load‑to‑grid flow (negative active power, surplus PV export).
The meter’s integrated 4G module (with SIM card tray) transmits data directly to the cellular network using MQTT over Modbus‑TCP—4G Electricity Meter direct uploadMQTT/Modbus-TCP—removing the need for a local gateway. An RS485 port remains available for local commissioning and fallback access.
Application Scenarios & Comparative Analysis
Typical deployments are small-scale industrial and commercial photovoltaic monitoring (10–100kWp) in retail, manufacturing, or office facilities. Two primary operating states are captured:
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PV < Load: Meter registers EPI (+kW) for grid supplementation.
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PV > Load: Meter registers EPE (–kW) for exported energy (feed‑in tariff or net‑metering).
| Parameter | Wired RS485 System | Wireless + External Gateway | ADW300‑4GHW/C Direct 4G |
|---|---|---|---|
| Hardware components | Meter + Gateway + Cabling | Meter + Gateway + Power | Meter only (SIM on board) |
| Installation hours (typical) | 6–8 | 4–5 | 2–3 |
| Single point of failure | No | Yes (gateway) | No |
| Additional hardware cost | $200–$450 | $150–$350 | $0 |
| Cloud integration | Custom build | Vendor‑dependent | Acrel ready out‑of‑box |
| Scalability (1000+ points) | Requires polling architecture | Gateway scaling limits | Direct cloud ingestion |
Selection considerations:
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For multi‑site projects, direct 4G eliminates per‑site network configuration.
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For retrofits, split‑core CTs minimize downtime.
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For pilot validation, the 3‑month free trial of Acrel IoT platform (all features active) reduces risk.
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For operators with existing cloud servers, the system supports 1000–2000 points on 8‑core 16G Windows Server.
FAQ
Q: What is the typical cellular data usage?
With 5‑minute readings, the meter consumes ~2–3 MB/day. A 500 MB monthly plan provides ample margin.
Q: Does the meter measure reactive power and power factor?
Yes, it measures all four quadrants of active/reactive power, including displacement and total power factor, aiding inverter performance analysis.
Q: What happens if 4G signal is lost?
The meter buffers data internally and retransmits upon reconnection. Accumulated energy registers are stored in non‑volatile memory regardless of communication status.
Q: Is the 3‑month trial fully functional?
Yes—all WEB and APP features (dashboard, history curves, reports, PDF/Excel export) are available during the trial without limitation.
Conclusion
The ADW300‑4GHW/C solution directly addresses bidirectional metering requirements, hardware cost reduction, and simplified cloud access for grid‑tied PV systems. For photovoltaic system integrator, EPC contractor, and power operation and maintenance service company, this approach lowers field labor, eliminates gateway maintenance, and streamlines central monitoring across multiple sites. The Acrel IoT platform’s automated daily/monthly/yearly reports (exportable to Excel/PDF) further reduce administrative overhead.
To evaluate this architecture on a single site, the 3‑month free trial offers a low‑risk validation path. For technical specifications or to request a sample unit, contact our engineering team with your site parameters (primary current rating and cellular coverage).