ZECO Energy has introduced a new diagnostic feature within Marshall Technology designed to identify abnormal impedance between an inverter’s AC output and the site’s point of supply, an issue that has been widely discussed across the industry following well-documented AC connector failures in Sigenergy single-phase 8/10/12 kW inverters.
Essentially, a hot connection at inverter grid outlet plug can be captured and the system can send automated emails to installers, OEMs and homeowners so the issues can be flagged before AC connector problems present.
The feature builds on Marshall’s existing ability to read both the site grid voltage and the inverter-reported AC voltage.
This new solution would see each morning, when the inverter is not generating, Marshall record a baseline percentage difference between the two values. This measurement - referred to internally as %Delta Voltage - is then tracked over time. If the difference exceeds a defined threshold or begins to drift in a way that suggests a rise in impedance, Marshall can flag the change for the installer.
ZECO Energy engineers have also prepared an alternative method for use during generation periods, where grid voltage naturally fluctuates due to daytime solar export. In these cases, Marshall can analyse the behaviour of the voltage ratio relative to export current, allowing abnormal patterns to be identified even under varying grid conditions.
This approach has been reviewed and refined through internal engineering work and subsequent discussions with engineers across the industry. It has now been formally presented to the broader sector as a practical, monitoring-based pathway to highlight abnormal inverter-to-grid conditions earlier and more reliably.
ZECO Energy Director Jag Makam said:
“Marshall already measures and records the values needed to identify these issues. Our team recognised the opportunity to turn that data into an early-warning tool for installers. This diagnostic feature is a direct response to what the industry has been talking about, and it gives installers clearer visibility where it’s needed most.”
Jag MakamThe diagnostic enhancement will be included in an upcoming Marshall software update. Installers and engineering partners can contact ZECO’s technical services team for further information or early-access participation.
