Key features
Inverter monitoring
Connect inverters from any brand (Huawei, SMA, Fronius, Solax, Growatt…) over private APN for real-time generation data.
Battery management
Telemetry for BESS storage: state of charge, cycle count, temperatures and degradation alerts.
Bidirectional meters
Remote reading of generation and consumption meters for surplus settlement and net billing.
Weather stations
Connect pyranometers, temperature probes and anemometers for performance ratio (PR) and soiling detection.
Site security
IP cameras, intrusion sensors and access control at remote solar plants.
O&M aggregation
Normalized data streamed into your O&M platform for portfolios of hundreds of sites.
Use cases
Typical problems
- Plants in rural areas with marginal single-operator coverage — the manufacturer's portal (Huawei FusionSolar, SMA Sunny Portal…) goes silent for days.
- Inverters with a SIM from an operator that doesn't cover the site, and nobody notices until the customer complains about unbilled exports.
- Inverter data flowing to the manufacturer's platform in China/Germany, raising GDPR concerns from the end customer.
- Unexpected roaming costs when the datalogger reboots and opens multiple sessions to the manufacturer's portal.
- Inability to push remote changes to the inverter (curtailment, reactive power, grid protection parameters) because it's behind operator CGNAT.
- Weather stations and pyranometers offline for days due to intermittent coverage, biasing the PR calculation.
Recommended architecture
- 1
Inverter datalogger with multi-operator SIM and private APN
The logger (Huawei SmartLogger, SMA Cluster Controller, Solar-Log…) carries a multi-IMSI SIM that picks the network with the best RSSI at the site. The private APN routes it to your VPC, not the manufacturer's portal.
- 2
Single backhaul per plant + Modbus TCP on the internal bus
One industrial router collects multiple inverters via Modbus TCP and reports aggregated to your O&M. Reduces SIM count (one per plant vs one per inverter) and gains centralized control capability.
- 3
Static IP + outbound rules for dynamic curtailment
The PPA operator or aggregator can issue power reduction commands (RBC, redispatch) via REST API to the datalogger. Without static IP, that flow needs an intermediate broker that adds latency.
- 4
Per-plant data plan with margin for weather events
A 50-100 kWp self-consumption plant uses 100-300 MB/month. During storms with many alarms and abnormal curves, consumption can spike 5x. Configure a generous plan + block alarm at 3x nominal.
Indicative data plan
| Device | Typical monthly traffic | Recommended plan |
|---|---|---|
| Residential inverter datalogger (5-10 kWp, 5-min reads) | 30-100 MB/month | 100 MB plan |
| Commercial datalogger (50-500 kWp, multiple traces) | 200 MB - 1 GB/month | 1 GB plan |
| BESS with intensive telemetry (every 30s) | 500 MB - 2 GB/month | 2 GB plan / Pooled data |
| Weather station + pyranometer | 10-50 MB/month | Smart-meter 50 MB plan |
Indicative figures. Plants with many alarms (partial shading, microinverters with individual events) consume significantly more.
When to use static IP
- The customer or aggregator needs to send commands to the inverter (curtailment, active/reactive power control, grid protection parameters).
- Regulatory audit (BOE-A-2020-7234, RD 244/2019 on self-consumption, ITC-BT-40) requires per-IP datalogger traceability.
- Integration with the electric operator's SCADA (REE, distribution company) for plants over 100 kW.
When to use private APN
- Generation and operational history must NOT leave the O&M operator's controlled environment (GDPR compliance, trade secret).
- Security: many Chinese inverters have documented vulnerabilities and must not be reachable from the public Internet (mandatory segmentation).
- Custom O&M platform that needs RFC1918 addressing and communicates with hundreds of inverters in a single VPC.
Compatible devices
Huawei SmartLogger 3000
Central logger for plants of up to 80 Huawei inverters. Supports Modbus TCP, MQTT to FusionSolar, and local API. MicroSIM slot and external antenna.
SMA Cluster Controller / Data Manager M
For SMA plants. Connects multiple inverters via internal bus and reports to Sunny Portal or your platform. Standard 2FF SIM.
Solar-Log 1200/2000
Universal multi-vendor logger (compatible with 1500+ inverters). Designed for O&M companies with mixed portfolios.
Fronius Smart Meter + Datamanager
Solution for Fronius residential and commercial self-consumption. WiFi + optional cellular module for sites without network.
Teltonika RUT240/RUT955 industrial routers
For large plants where multiple inverters share a single cellular backhaul. Support WAN failover, OpenVPN, modbus gateway.
Lufft / Kipp & Zonen weather stations
Pyranometers, module and ambient temperature sensors, anemometers. Report via Modbus to the datalogger or via SDI-12 to a separate controller.
Frequently asked questions
- Why not use the customer's WiFi to connect the inverter?
- Works for residential self-consumption without O&M requirements, but customer WiFi changes SSID, password or router without notice. For professional portfolios, a dedicated SIM at the inverter guarantees stable connectivity independent of the end customer.
- Will my generation data stay in Spain with private APN?
- Yes. Traffic tunnels into your VPC in the region you choose (eu-west-1 / eu-west-3 for Spain). Data does not pass through the manufacturer's portal. Important for corporate customers and public administrations with strict GDPR.
- Is NB-IoT good for solar inverters?
- For summary reports (instant power, daily energy), yes. For detailed telemetry (IV curves, individual alarms, event logs), NB-IoT falls short on throughput — use LTE-M or classic 4G. NB-IoT is ideal for bidirectional meters and weather stations, not for the central datalogger.
- Can I control inverter active power via API from my O&M platform?
- Yes, if the inverter supports it (most modern ones do: Huawei SUN2000, SMA Sunny Tripower CORE1, Fronius SYMO GEN24, etc.) and you have static IP at the datalogger. The command goes via Modbus TCP or REST API depending on the manufacturer. Without static IP you need an intermediate broker.
- How many SIMs do I need for a 200 kWp plant with 5 inverters?
- Just one: the central datalogger groups the 5 inverters via internal Modbus and reports them consolidated. If inverters are physically dispersed (more than 100m apart) you may need 2-3 dataloggers, but rarely one SIM per inverter.
Pre-deployment checklist
- 1Per-plant inventory: inverter type and model, datalogger, bidirectional meter, BESS if any.
- 2Coverage map by postal code and operator before choosing SIM — rural areas may have only one operator with acceptable signal.
- 3Manufacturer's portal vs custom O&M platform decision (GDPR, data ownership).
- 4Static IP decision (yes for plants >100kW with curtailment) vs dynamic IP.
- 5Public APN with encryption for residential, private APN for commercial and industrial.
- 6Per-plant data plan with 3x margin for weather events and cascading alarms.
- 7Decommission procedure for plant teardown.
- 8RD 244/2019 (self-consumption) and ITC-BT-40 compliance, especially traceability of exported surplus.
- 9Datalogger support for local Modbus TCP when the customer wants to integrate with their BMS or SCADA.
- 10Pilot of 2-3 plants for 2 months validating telemetry uptime and PR calculation accuracy.
Need a printable version? See the pre-deployment guide.
Have a project in mind?
Tell us your use case and we'll help you find the best connectivity solution.