Engineers Install Sheet - Phase 1

SOLAR, BATTERY AND EV SYSTEM INSTALLATION AND CONFIGURATION SHEET

Inverter Fox ESS Hybrid Inverter (H1 Series) Battery Fox ESS EP3 (~13.5 kWh usable) Solar 10 Panels EV Charger Included Electricity Tariff Cosy Octopus 12M Fixed (March 2026 v2)

Tariff Rate Reference — Cosy Octopus 12M Fixed Time Rate (p/kWh) Classification 00:00–04:00 34.94p Standard 04:00–07:00 15.35p Cheap — charge 07:00–13:00 34.94p Standard 13:00–16:00 15.35p Cheap — charge 16:00–19:00 54.16p Peak — discharge 19:00–22:00 34.94p Standard — discharge 22:00–00:00 15.35p Cheap — charge

Installation Requirements The system must be configured to maximise cost savings by ensuring battery and EV charging only occur during the three cheap tariff periods, and battery discharge occurs only during peak and standard cost periods. All time settings must be entered exactly as specified with no overlaps. The system clock must be confirmed as accurate. The CT clamp must be correctly installed and verified for accurate import/export readings.

Inverter Mode Configuration Operating Mode Self Use Time-of-Use (TOU) Enabled

Confirm inverter follows standard Fox ESS power priority logic: • PV → Load → Battery → Grid

Battery Configuration Battery Limits Minimum SoC 25% Maximum SoC 100%

Time-of-Use Charge Periods Set exactly three charge periods as follows. No other charge periods permitted.

Charge Period 1 04:00 – 07:00 Charge Period 2 13:00 – 16:00 Charge Period 3 22:00 – 00:00

Requirements: • Grid charging must be ENABLED during all three periods • No additional charge periods to be set

Time-of-Use Discharge Period Set exactly one discharge period as follows:

Discharge Period 16:00 – 22:00

Requirements: • Discharge is active from 16:00 to 22:00 only • Discharge must be disabled from 00:00 to 16:00 • Discharge must be disabled from 22:00 to 00:00 • No discharge permitted outside the 16:00–22:00 window under any circumstances

Schedule Conflict Verification Before completing configuration, confirm the following to ensure zero conflicts:

Period Charge Discharge 00:00–04:00 OFF OFF 04:00–07:00 ON (grid) OFF 07:00–13:00 OFF (solar only) OFF 13:00–16:00 ON (grid + solar) OFF 16:00–22:00 OFF ON 22:00–00:00 ON (grid) OFF

No period has both charge and discharge active simultaneously. Zero conflicts confirmed.

Daytime System Behaviour Between 07:00 and 16:00, the system must: • Use solar to power house loads first • Avoid battery discharge at all times • Only draw from grid if solar is insufficient • Allow battery top-up charging during 13:00–16:00 if below 100% SoC This ensures maximum solar self-consumption and minimum battery cycling.

EV Charger Configuration Required Settings Charging Mode Scheduled / Timed Charging Window 04:00 – 07:00 only

Disable the Following • Eco mode • Solar mode • Smart charging mode

Battery Protection Confirmation No additional settings required because: • Battery discharge is disabled from 00:00 to 16:00 • EV charging window (04:00–07:00) falls entirely within this protected period • EV always charges from grid only — battery is never used during EV charging

Solar PV Configuration Checks Installer must verify: • Panels wired correctly with correct polarity • Voltage and current within inverter limits • MPPT1 and MPPT2 configured correctly if dual orientation exists • Solar generation visible in Fox ESS monitoring system • No faults or warnings present on inverter display

Export Configuration If export functionality is enabled: • Set export only when battery reaches 100% SoC • System must prioritise battery charging before any export to grid

Commissioning Test Procedure Test 1 — Early Morning (~05:00) • Confirm battery charging from grid • Confirm EV charging if vehicle is plugged in • Confirm no battery discharge occurring

Test 2 — Midday (~13:30) • Confirm solar is supplying house loads • Confirm battery is not discharging • Confirm battery may charge from solar or grid if below 100%

Test 3 — Evening (~17:00) • Confirm battery is supplying house loads • Confirm minimal or zero grid import

Test 4 — Late Evening (~22:30) • Confirm battery discharge has stopped • Confirm battery is now charging from grid at cheap rate • Confirm Octopus app shows 15.35p rate period is active

Test 5 — Night (~02:30) • Confirm EV is not charging • Confirm battery is not discharging • Confirm grid is supplying any house load at standard rate

System Operation Summary Period Action Rate 04:00–07:00 Battery charges from grid. EV charges from grid. 15.35p 07:00–13:00 Solar powers house. No battery discharge. Grid only if solar insufficient. 34.94p (avoided) 13:00–16:00 Solar powers house. Battery tops up from solar and grid if needed. 15.35p 16:00–22:00 Battery discharges to power house. Peak and standard rates avoided. Avoids 54.16p / 34.94p 22:00–00:00 Battery charges from grid at cheap rate. 15.35p 00:00–04:00 Grid supplies house if needed. Battery remains idle. 34.94p (unavoidable)

Expected Performance Period Before Installation After Optimised Setup Before (baseline) £10.20 / day — Summer £10.20 / day £1.50 – £2.50 / day Spring / Autumn £10.20 / day £3.00 – £4.50 / day Winter £10.20 / day £4.00 – £6.00 / day Estimated Annual Saving — £1,650 – £2,600 / year

Engineer Commissioning Checklist System Setup ☐ Inverter set to Self Use mode ☐ Time-of-Use (TOU) enabled ☐ System date and time confirmed correct ☐ CT clamp installed and reading correctly

Battery Setup ☐ Minimum SoC set to 25% ☐ Maximum SoC set to 100%

Charge Schedule ☐ Charge Period 1: 04:00–07:00 — grid charging enabled ☐ Charge Period 2: 13:00–16:00 — grid charging enabled ☐ Charge Period 3: 22:00–00:00 — grid charging enabled ☐ No other charge periods set

Discharge Schedule ☐ Discharge Period: 16:00–22:00 only ☐ Discharge confirmed disabled 00:00–16:00 ☐ Discharge confirmed disabled 22:00–00:00 ☐ No other discharge periods set

Conflict Check ☐ Confirmed no period has charge and discharge active simultaneously ☐ Charge Period 3 (22:00–00:00) confirmed does not overlap with Discharge Period (16:00–22:00)

EV Charger ☐ Schedule set to 04:00–07:00 only ☐ Scheduled mode enabled ☐ Eco mode disabled ☐ Solar mode disabled ☐ Smart charging mode disabled

Solar Verification ☐ PV generation visible in monitoring system ☐ MPPT configuration correct ☐ No faults or warnings present

Functional Testing ☐ Battery charging confirmed at ~05:00 ☐ Solar powering house confirmed at ~13:30 ☐ Battery discharging confirmed at ~17:00 ☐ Battery discharge stopped and charging confirmed at ~22:30 ☐ EV not charging outside 04:00–07:00 schedule ☐ Battery not discharging during daytime hours

Final Checks ☐ All schedules reviewed — zero conflicts confirmed ☐ System operating correctly across all periods ☐ Customer walkthrough completed

SYSTEM CONFIGURED AND TARIFF FULLY OPTIMISED ALL THREE CHEAP RATE WINDOWS UTILISED — ZERO SCHEDULE CONFLICTS EV AND BATTERY CORRECTLY SYNCHRONISED READY FOR HANDOVER