PV commissioning pack

The handover bundle after a solar install: commissioning test results, certificates, warranties, monitoring and system documentation, and how to tell a complete pack from a thin one.

A PV commissioning pack is the set of documents an installer hands over once a solar PV system has been commissioned. It records the commissioning checks, test results, certificates, warranties and system documentation that together show the installation is safe, has been built to the standard and is generating as designed.

The pack is a bundle rather than a single certificate. It is not itself the planning consent, the DNO approval, the MCS certificate, the building regulations certificate or the warranty registration. It is the folder that collects those separate documents in one place for the homeowner. MCS MIS 3002, the installation standard for domestic solar PV, requires that a system is commissioned to a documented procedure confirming the system is safe, correctly installed to the standard and the manufacturer’s requirements and generating to the system design.

The documents a complete pack contains

The MCS Customer Commitment sets the guaranteed floor. An installer who is MCS-certified must provide a handover pack once the installation is complete containing, as a minimum:

A list of the key parts
Health and safety guidance
A recommended servicing and maintenance schedule
The manufacturer’s instruction manuals
All relevant guarantees and warranties

A thorough installer goes well beyond that minimum. A fuller pack also includes:

A system design summary with layout diagrams, a schematic and component specifications
The MCS certificate
The Electrical Installation Certificate (EIC) covering the AC and DC electrical work
The building regulations compliance certificate
The DNO notification or approval
The commissioning test results
A user manual explaining how to operate and monitor the system and read the inverter display
Warranty documents for the panels, inverter, workmanship and mounting
The performance estimate, the expected annual generation in kWh
Emergency and shutdown procedures, including how to isolate the system
The invoice or receipt

MCS MIS 3002 itself sets out model templates for the core paperwork: a handover document, a PV system verification certificate and a model PV array test report. These are the standardised documents a complete pack should contain.

MCS 001-1, the contractor standard, requires the installer to keep records for each job that include the survey documents, quotations, orders, risk assessments, commissioning checks, certification, building regulations notifications and copies of the MCS certificates. Those records overlap with the pack but are held by the installer rather than always handed over, so the pack the homeowner receives can be thinner than the file the installer keeps.

The commissioning tests and what the results show

BS EN 62446-1 is the British Standard for the documentation, commissioning tests and inspection of grid-connected PV systems, and it is the reference the test results in the pack are built around. Several checks are done before the strings are connected to the inverter, while the array can still be treated as a set of DC sources.

Test	What it checks	What a poor result points to
DC polarity	Correct positive and negative at each string connector	A zero reading is an open circuit; a reversed reading is a wiring error
String open-circuit voltage (Voc)	Each string near its expected voltage: modules in series multiplied by the per-module Voc, adjusted for temperature	A low reading suggests a faulty or missing module; a very low reading a short circuit
DC insulation resistance	Insulation between each conductor and earth, and between conductors, using an insulation-resistance tester	New cabling often reads well above 200 megohms; below 1 megohm points to damaged insulation, water in a connector or a panel defect
Earth bond continuity	Resistance from the mounting rail or panel frame to the Main Earthing Terminal at the consumer unit	A reading above about 1 ohm indicates a poor or missing bond

String Voc reads a little above the standard-test-conditions figure at UK temperatures, a few per cent higher at an ambient around 15°C, because open-circuit voltage rises as the panels cool. The insulation-resistance test is usually run at 500 V DC for a domestic string, with the test voltage keyed to the array’s maximum voltage and capped by the module’s own rated limit.

Before any of this, a visual inspection confirms the connections, cable routes, fixings and labelling: panels seated on their rails, clamps torqued, the DC connectors fully clicked home, the array earth bond connected and the DC cable entry sealed. Once the inverter is energised and the grid is live, a functional test confirms the inverter powers up, synchronises and begins generating. The anti-islanding test then opens the AC supply briefly; the inverter must shut down within about two seconds, so that it cannot keep a disconnected section of the network live while someone works on it. An RCD (residual current device) test at the consumer unit checks the AC-side protection, with a 30 mA trip expected to operate within 300 milliseconds.

The Electrical Installation Certificate and DC safety

Every solar PV installation needs an Electrical Installation Certificate (EIC) to BS 7671, the IET (Institution of Engineering and Technology) Wiring Regulations. The EIC covers both sides of the inverter: the DC side, meaning the panels, string cables and DC isolator, and the AC side, meaning the inverter output, AC isolator and the connection into the consumer unit. Section 712 of BS 7671 sets the solar-specific requirements the certificate records against.

The certificate documents the wiring on both sides, the earthing and bonding arrangements and the test results: continuity, insulation resistance, polarity, earth fault loop impedance, RCD operation and the DC string voltage and current readings. It also records which DC-side protective method was used, and confirms the mandatory warning labels are fitted. BS 7671 requires a permanent warning notice at every point where DC parts can be accessed and a warning notice on every inverter. Missing labels are a frequent MCS audit non-conformance, so their presence is part of what the certificate signs off.

The DC side is treated as live whenever the panels are in daylight. Under BS 7671, DC equipment is considered energised even when the AC side is disconnected from the grid and the inverter is isolated from the array. DC connectors are made to BS EN 62852, and where they are within reach of non-skilled persons they must need a key or a tool to separate, so they cannot be pulled apart by hand under load.

MCS certificate, building regulations and DNO notification

The MCS certificate is lodged on the MCS database and is the document a SEG application relies on. The MCS consumer guidance says the certificate is issued within 10 working days of completion, which is the usual practice. The Customer Commitment sets the formal deadline differently: within 30 calendar days of completion the installer must provide the MCS certificate, any building regulations compliance certificates and proof of the DNO notification or approval. Treat the 10 working days as the typical target and the 30 calendar days as the outer limit the installer has committed to.

Solar PV is notifiable electrical work under Part P of the Building Regulations. When the work is done by an MCS-certified installer, Part P is handled by self-certification through the installer’s competent person scheme, such as NICEIC or NAPIT, and the building regulations compliance certificate follows from that. Parts of the Building Regulations beyond Part P can also bear on a PV job, covering the roof’s ability to carry the load, fire safety, moisture at cable penetrations and safe working at height. The building regulations Parts L and P entry covers how those apply.

The DNO notification confirms the network operator knows about the generation. Systems up to 16 A per phase use the G98 connect-and-notify route, with the notification submitted within 28 days of installation; larger systems use G99, which is applied for before the work is done. The DNO notification for PV entry sets out which route applies and the paperwork each involves.

The warranties in the pack

A solar installation carries several warranties from different parties, and the pack should hold the paperwork for each.

Workmanship, from the installer. MCS sets a minimum of two years; individual installers can offer longer, five years in some cases.
Product, from the manufacturer. Panels are typically warranted for 10 to 25 years and inverters for 5 to 10 years.
Performance, on the panels. The manufacturer guarantees the modules will still produce at least a stated share of their rated output over time, often around 80 to 90 per cent at 25 years.

Some manufacturers require the system to be registered before the warranty is valid, so a warranty document in the pack is not always the end of the job. Where registration is needed, it has to be completed for the cover to hold.

Monitoring set up at handover

Inverter monitoring should be set up and demonstrated at handover so the owner can see generation from the start. The inverter connects over ethernet, WiFi or a cellular link to a data logger that gathers readings from the inverter, meters and any sensors, and sends them to a web platform for real-time viewing. The platform depends on the equipment fitted, with systems such as Fronius Solar.web, SolarEdge and Enphase Enlighten among the common ones. Installed GivEnergy systems use a platform now operated by a separate software company after the hardware company ceased trading in April 2026. The monitoring portal data entry covers what these platforms show and their limits.

What is often missing from a handover

Homeowners frequently report receiving far less than a complete pack. A common pattern is getting only the MCS certificate and the DNO confirmation, with the EIC, the building control notification, the schematics and the warranty details absent. Some report waiting weeks with just the MCS certificate and a G99 letter to show for it.

If the pack is thin, the items worth chasing are the EIC, the building regulations compliance certificate, the commissioning test results, the system schematic, the performance estimate and the individual warranty documents. The EIC and the commissioning test results matter most, because they are the evidence the DC and AC electrical work was tested and signed off.