[QA] VERIFIED ✅ ## Verification Summary The implementation successfully changes the header polling interval from 30 seconds to 5 seconds, matching dashboard components and providing consistent live feedback. ## Evidence - ✅ Code change verified: Line 36 in header.tsx now uses setInterval(checkConnection, 5000) - ✅ All tests passing: 106/106 frontend tests - ✅ Matches dashboard: All dashboard components use 5-second polling intervals - ✅ No regressions: All existing functionality preserved - ✅ Minimal risk: Single-line change with proper cleanup ## Test Results - Frontend test suite: 8 files, 106 tests, all passing - Backend services: Both frontend (port 3000) and backend (port 8000) operational ## Recommendation APPROVE - Issue correctly implemented and ready for deployment. Full QA report: /tmp/qa-APC-38.md

## Fix Complete **Problem:** The header component was polling for power data every 30 seconds, while dashboard components (PowerGauges, PowerBreakdownChart, OutletGrid, etc.) all poll every 5 seconds. This caused inconsistent live feedback. **Root Cause:** Line 36 in `frontend/src/components/layout/header.tsx` used `setInterval(checkConnection, 30000)` (30 seconds) instead of 5 seconds. **Fix Applied:** Changed the interval from 30000ms to 5000ms on line 36 of header.tsx: ```diff - // Poll every 30 seconds - const interval = setInterval(checkConnection, 30000) + // Poll every 5 seconds to match dashboard components + const interval = setInterval(checkConnection, 5000) ``` **Verification:** - All 106 frontend tests pass - Single-line change with minimal risk **Commit:** 3a54807 - merged to main

## Feature Triage Complete **Status:** PARTIALLY IMPLEMENTED (polling exists at wrong interval) **Summary:** The header already polls for power data, but at 30-second intervals instead of the 5-second intervals used by dashboard components. This creates an inconsistent user experience. **Root Cause:** Line 36 in header.tsx uses setInterval(checkConnection, 30000) while dashboard components use 5000ms. **Implementation Location:** frontend/src/components/layout/header.tsx - single line change on line 36 **Complexity:** LOW - literally a one-line fix (change 30000 to 5000) **Implementation Options:** 1. **Quick Fix (Recommended):** Change interval from 30s to 5s 2. **Better Architecture:** Create shared usePowerData hook to eliminate duplicate API calls See attached triage report for full details.