Induction cooktop shows E7 intermittently, often when multiple zones are used at high power.

Safety first: Turn off the appliance at the mains before inspecting wiring.

• Check circuit rating: Confirm that the cooktop is connected to a circuit with the correct amperage as specified on the rating plate. Avoid using other heavy loads on the same circuit.
• Inspect terminal block: With power off, open the terminal cover and check for tight, secure connections. Tighten any loose screws.
• Verify configuration: Ensure the bridging links on the terminal block are set correctly for single-phase or two-phase installation as per Gram's diagram.
• Test under reduced load: Restore power and test with fewer zones or lower power. If E7 disappears under reduced load, the issue may be supply-related rather than a defect.
• Module diagnosis: If E7 appears even at low load and wiring is correct, the current sensing circuit on the power module may be faulty and the module should be replaced.

Warning: Do not upsize circuit breakers without verifying cable capacity. This is an electrician's task.