Enphase IQ Battery 5P installation: what the job involves

Video reference. "Enphase IQ Battery 5P : Introduction" is from Enphase Energy. It introduces the IQ Battery 5P system, covering the key features, AC-coupling approach, grid-forming capability and the Enlighten monitoring platform used during commissioning.

1. Surveying the site and checking existing solar compatibility

The IQ Battery 5P is an AC-coupled system. It connects into the household AC wiring, not into the solar inverter's DC output. This means it can work alongside a Fronius, SolarEdge, SMA, GoodWe, or almost any other existing solar inverter without replacing it. The installer confirms the consumer unit has a spare way for the battery circuit, checks the proposed installation wall for strength and ventilation, and reviews the G98 or G99 export registration already in place for the solar system.

If the solar system is already close to the G98 export limit of 3.68 kW per phase, the installer discusses with you whether the battery's contribution to export needs to be limited, or whether a G99 pre-approval from the DNO is appropriate before the battery is added.

2. Planning capacity and the number of units

Each IQ Battery 5P unit provides 5.0 kWh of usable storage. Households with a 4 kWp solar array and typical daily consumption of 8 to 12 kWh often find one or two units practical. The installer reviews actual consumption data where available, the solar generation profile, and any overnight EV charging. Where the household is on an octopus-style cheap overnight tariff, the battery can also be scheduled to charge from cheap grid electricity in the early hours, which affects the sizing recommendation.

3. Mounting the battery units

Each IQ Battery 5P wall-mounts on a bracket. The installer marks fixing positions, drills into masonry or appropriate substrate, fits the brackets and checks each unit is level. Adequate clearance around each unit is maintained for ventilation. If multiple units are being installed, they mount side by side with a small gap between them as specified in the installation guide.

4. Running the AC circuit and connecting the units

A dedicated AC circuit runs from the consumer unit to the battery installation. Cable cross-section is chosen for the battery's rated output current and the cable run length, keeping volt drop within BS 7671 Regulation 525 limits. An RCBO or MCB at the consumer unit protects the circuit. Each battery unit connects to the cable in the sequence shown in the installation guide, with the correct terminal torque applied. Polarity, earth continuity and insulation resistance tests are carried out before the circuit is energised.

5. Fitting the CT clamp

An Enphase CT clamp fits around the grid import conductor in the consumer unit area, giving the system a live reading of how much power the house is drawing from or returning to the grid. The system uses this to decide when to charge from solar surplus and when to discharge to cut import. Reversing the CT inverts the reading, so the installer confirms the polarity by checking the reading matches the known load on the circuit before completing commissioning.

6. Commissioning on Enlighten and certifying

The Enphase Installer app is used to activate each battery unit and bring it onto the Enlighten monitoring platform. Tariff schedules, export limits and backup mode settings are configured to match the household's tariff and requirements. A test charge and discharge cycle confirms the CT clamp is reading correctly and the battery responds as expected.

The installation is notified through the installer's Part P competent person scheme and you receive an Electrical Installation Certificate. DNO notification follows G98 for export up to 3.68 kW per phase, with the DNO notified within 28 days. If the combined solar and battery export exceeds the G98 limit, G99 pre-approval is needed before commissioning. Keep the EIC and DNO paperwork with your property documents.

When to call us

Richard installs home battery storage systems across east Kent, including Enphase IQ Battery and other brands. He handles the mounting, AC circuit, CT clamp, Enlighten commissioning, Part P certification and DNO notification. Get in touch for a free fixed quote.