Troubleshooting & Validation

The Design Tool should block invalid designs with validation messages instead of crashing or silently continuing. Treat validation as guidance: it usually means the tool has found a missing field, incomplete topology, or electrical rule that must be resolved before outputs are reliable.

Common Messages And What They Mean

Required Fields Missing

Use the Required Fields band in Step 3. Click Next missing to jump to the next blocking or recommended field.

Typical causes:

• Device catalog/model not confirmed.
• Meter or MSP ratings are incomplete.
• Location/placement is missing.
• Grounding or bonding has not been confirmed.
• Tie-in is not saved.
• Electrical one-line auto-confirmation has not been resolved.

Aggregator Not Connected To Grid

The inverter or combiner is not electrically connected to the service path in a way the design can validate. Check the one-line graph and tie-in card.

Typical causes:

• Missing connection from inverter/combiner to disconnect/MSP.
• Battery or PV circuit is connected, but the AC output is not.
• A device was deleted or rewired without saving a valid graph.
• The tie-in declaration is missing or no longer matches the graph.

No Service Disconnecting Means

The service path is missing a required service disconnecting means. This often appears after deleting or rewiring meter/MSP/disconnect nodes. The exact red design-check reads: "No service disconnecting means (NEC 230.70) — add a main breaker / service disconnect grid-ward of distribution," often paired with a bond tooltip: "Service disconnect / N-G bond moved to no device — recheck the main breaker + bond disposition."

What to do:

• Restore or add the correct service disconnect device.
• Confirm whether the service is detached or attached/meter-main.
• Recheck grounding and bonding after topology changes — deleting the panel/disconnect can orphan the N-G bond, which the tooltip above is flagging.

Note: deleting a non-service node (e.g. a PV AC disconnect) is handled gracefully — the tool shows a "Removed — run reconnected" toast, auto-reconnects the run, and the wire-schedule count drops by one. It is only the service disconnecting means whose removal raises the blocking design check above.

Step Won't Advance — "Step Incomplete · N Items Required"

Clicking Next while Step 3 has unresolved blocking errors does not navigate — it opens a "STEP INCOMPLETE · N ITEMS REQUIRED" panel listing each issue with "Jump to" links. This is expected: the wizard blocks forward navigation until the design is valid, rather than carrying a broken design into the wire schedule.

What to do:

• Use the Jump to links to resolve each listed item, or the Required Fields band's Next missing button.
• Re-check after each fix; the count decrements as items clear.

Terminal Cap Stale (TERMINAL_CAP_STALE_AHJ_DEFAULT)

The wire schedule (Step 4) flags one or more raceways whose terminal-temperature cap is still a stored AHJ/catalog default (commonly a 75 °C default on a disconnect such as the Eaton DG222URB) instead of a confirmed value.

Why: terminal ampacity at 110.14(C) is sized against the terminal temperature column; an unconfirmed default may not reflect the installed equipment's real rating.

What to do:

• Open the flagged raceway(s) and confirm or override the terminal cap.
• This is a non-blocking advisory — the schedule still computes — but resolve it before relying on the sized ampacity.

"No Eligible Devices Here" When Adding an Islanding / Gateway Device

You opened the device picker to add a Tesla Gateway 3, Backup Switch, IQ Meter Collar, or similar islanding device, and the list is empty with "No eligible devices here."

Why: these are service-region devices, and you opened the picker from the PV production side (the inverter or combiner). That side of the graph is not eligible for a service-disconnect/microgrid device.

What to do:

• Add the device from the utility meter or the main service panel instead, toward the service side. A Gateway 3 is typically added as a meter intercept (it splices in between the meter and the main panel).
• Once placed, crown it as the service disconnect ("Make service disconnect" or "Back up the existing MSP") and pick the NEC-sized main. See the interconnection guide, "When the gateway IS the service disconnect."
• Note: a whole-home gateway design will then show no separate load-side tie-in — that is correct, not a missing field.

Load-Side Tap Has No Breaker Rating

An export or netlist refuses with "uncovered topology" / no breaker for ACTIVE_BREAKER_RATING, on a load-side tap interconnection.

Why: a load-side tap lands on a feeder/extension point that still needs an overcurrent rating to size against; until the landing device's outgoing/feed-through breaker is authored, the tool refuses rather than emit a blank rating.

What to do:

• Author the landing device's breaker/OCPD rating (the back-fed breaker for a breaker tie-in, or the feeder/tap OCPD for a tap).
• Confirm the tie-in method matches the physical landing (breaker vs. tap vs. lug).

Busbar Or PCS Warning

Step 3 may show NEC 705.12 or PCS-related warnings when breaker size, main breaker, bus rating, existing breakers, or PCS controls affect interconnection eligibility.

What to do:

• Verify MSP bus rating and main breaker size.
• Verify PV breaker/OCPD size.
• Check whether PCS is active and whether the selected control mode is correct.
• Confirm the landing panel and tie-in method.

Wire Schedule Voltage-Drop Warning

The wire schedule may flag total voltage drop over target. This is not always a crash or blocking failure, but it should be reviewed.

What to do:

• Confirm raceway lengths and conductor paths.
• Check current inputs and OCPD values.
• Review the Full NEC table before accepting or overriding.

Blank Or Slow Step Navigation

Some direct step navigation can briefly show a blank or loading state before the wizard renders. For documentation, avoid direct URL jumps in clips unless you are intentionally documenting navigation behavior.

What to do:

• Use the wizard navigation buttons for normal walkthrough footage.
• Wait until the step content is visibly loaded before narrating.
• If a blank state persists, note the session ID, source step, target step, and timing.