Helpful video reference. We use Gary Does Solar's installation walkthrough "SunSynk 3.6kW Ecco Solar and Battery Storage Installation" as the video reference here. Gary covers the UK-specific elements correctly throughout, including the PAS 63100 siting requirements and the G98/G99 DNO notification process. The installation shown is a DC-coupled system on a UK domestic property.
1. Site survey and PAS 63100 assessment
Every MCS-certified battery installation begins with a site survey. The installer assesses the wall structure and loadbearing capacity (battery modules are heavy), the ventilation in the proposed location, the proximity of the equipment to habitable rooms and escape routes, and the cable route from the proposed location to the consumer unit and the solar array.
PAS 63100 sets out specific clearance distances and siting restrictions. A battery cannot be installed in a bedroom, for example, and must maintain specified distances from gas boilers and meters. The site survey is where all of this is agreed before a single fixings goes in.
2. AC coupling or DC coupling: which applies to your system?
This is the most important technical decision in the project, and it depends on whether you already have solar panels.
DC coupling means the solar panel cables come directly to the Sunsynk hybrid inverter. The hybrid inverter handles both the conversion of solar DC to usable AC and the charging of the battery, all in one unit. This is the most efficient arrangement but requires replacing your existing solar inverter (if you have one) with the Sunsynk unit.
AC coupling means your existing solar inverter stays in place and the Sunsynk battery connects to the AC side of the system via a dedicated circuit from the consumer unit. Energy is converted twice rather than once, so there is a small efficiency penalty, but you keep your existing inverter and its warranty.
If you have no existing solar at all, the installer will specify a DC-coupled Sunsynk hybrid system from scratch, with panels and inverter specified together.
3. DNO notification under G98 or G99
Before installation can proceed, the correct notification must be made to your Distribution Network Operator (DNO). The DNO is the company that owns the local electricity cables: UK Power Networks in east Kent.
Most Sunsynk hybrid systems exceed 3.68 kVA per phase, which triggers G99. G99 requires written DNO pre-approval before the installation starts. The DNO has up to 65 business days to respond, though most residential applications are approved in two to four weeks. Your installer submits the application and waits for acceptance before booking the installation.
Some smaller AC-coupled battery additions fall under G98, which requires only a seven-day notification after installation. The installer determines which applies during the survey.
4. Mounting the inverter and battery modules
The Sunsynk hybrid inverter is wall-mounted in the chosen location. Battery modules are stacked beside it, either directly on the floor on a base plate or on a purpose-made rack. The installer checks the wall fixings can carry the weight and that the thermal management clearances around each module are correct.
Cable management between the inverter and battery stack is important: the DC bus cables between them carry high currents and must be correctly sized, routed, and protected.
5. DC solar connection (DC coupling)
For DC-coupled systems, the existing DC cables from the roof are connected to the Sunsynk inverter's MPPT (maximum power point tracking) inputs. The installer checks the open-circuit voltage of the string against the inverter's DC input limits before connecting. If the existing string wiring is not correctly fused or the connectors are not the right type for the Sunsynk, replacements are fitted at this stage.
6. AC consumer unit connection
A dedicated circuit connects the Sunsynk inverter's AC output to the consumer unit. The installer fits an appropriately rated RCBO or MCB for this circuit. The cable is sized for the inverter's rated output, not just the average generation figure.
A CT clamp is fitted around the grid import conductor inside the consumer unit enclosure. A thin signal cable runs from the CT clamp to the Sunsynk inverter. The CT clamp is what allows the system to see exactly how much power is being imported from or exported to the grid at any moment, which is essential for intelligent charging and the grid export limit function.
7. Commissioning via the SolarmanPV app
With all electrical work complete and tested, the installer connects the Sunsynk to the SolarmanPV monitoring platform. They configure the system operating mode to match your priorities (maximise self-consumption, prioritise battery charging from solar, enable grid export to the Smart Export Guarantee, or time-of-use arbitrage on an Agile tariff).
The charge and discharge schedule is set based on your typical usage pattern and your tariff. You receive login credentials for the SolarmanPV app, which shows live generation, battery state of charge, consumption and grid import/export in real time. The installer should walk you through the app before leaving.
8. Documentation you should receive
A correctly completed MCS installation produces a set of paperwork you should keep in a safe place: the MCS certificate (your proof of eligible installation for the Smart Export Guarantee), the Electrical Installation Certificate under BS 7671, the DNO notification acceptance letter, and the PAS 63100 site assessment record. If any of these are missing, ask for them before the installer leaves.
When to call us
Richard installs Sunsynk and other battery storage systems across east Kent, including Sandwich, Deal, Dover, Folkestone and Canterbury. Every installation is MCS-certified, PAS 63100 compliant, and fully documented. Get in touch for a free site survey and quote.
Interested in a Sunsynk battery for your east Kent home?
Richard provides MCS-certified solar battery storage installations across east Kent. Free site survey, all DNO paperwork handled, full documentation on completion.
Contact Richard