Mounting & Installation - K2 Systems
Modules and inverters only become a PV system when combined with the installation materials: the substructure is predominantly from K2 Systems, whilst solar cables, MC4-connectors and tools are predominantly from Stäubli, along with smart meters, energy meters and power optimisers.
The ‘Assembly & Installation’ section covers the materials needed to turn modules and an inverter into a complete PV system: the roof substructure, solar cables and MC4-connectors, crimping and assembly tools, as well as smart meters, energy meters and power optimisers. The majority of these are supplied by K2 Systems (mounting systems) and Stäubli (connectors, cable assemblies and tools).
Important to note: This category offers PV mounting and installation materials for sale; it does not include any services. ACTEC does not offer any mounting or installation services. You organise the installation yourself. For the electrical connection of a system, a qualified electrical contractor is the right point of contact.
Three areas: roof, cabling, metering
The substructure for PV systems connects the modules to the building. For pitched roofs, there are roof hooks for various types of roofing, including specialised hooks for slate and plain-end tiles, as well as hanger bolts and the SingleRail 36 and SolidRail Light rails in lengths from 2.40 to 5.95 m. On double-seam standing seam roofs, the CF:x seam clamp secures the rail without piercing the sheet metal. For trapezoidal sheet metal, the MiniRail and BasicRail 22 systems are available. On flat roofs, the D-Dome 6.10 east-west mounting system is used, which is also available as pre-assembled kits for 2 to 12 modules.
PV cables and connectors are used to run the cable from the module to the inverter and on into the house: H1Z2Z2-K-type solar cables with cross-sections of 4 and 6 mm², a green-and-yellow cable with a cross-section of 16 mm² for equipotential bonding, in-line fuses and Y-splitters from Stäubli, connection cables for storage units from Growatt and SAJ, and Schuko connection cables for micro inverters. The connectors are from Stäubli: plugs and sockets from the MC4 and MC4-Evo 2 systems for conductor cross-sections from 4 to 10 mm², branch plugs and sealing caps. Crimping pliers, wire strippers, installation wrenches and test probes are all kept together with the tools for MC4-connectors.
Smart meters and energy meters measure consumption and grid feed-in at the grid connection; the inverter uses these values, for example, to control the storage system or to limit the grid feed-in. The inverter’s data sheet specifies which meter is suitable. Power optimisers from BRC Solar are fitted to individual modules and compensate for any shading on part of the string. Refrigerant pipes and wall brackets for split air conditioners can be found in the air conditioner accessories section.
What should be clarified before placing an order
Three specifications determine the bill of materials for the substructure. The roof covering determines which roof hooks or fixings are suitable. The frame height of the modules determines the clamps: the centre and end clamps in the range are designed for specific ranges, such as 25 to 40, 30 to 42 or 30 to 50 mm. Finally, the number and orientation of the modules determine how many metres of rail, connectors and end caps are required.
When it comes to cabling, the cross-section and connector system are key. The cross-section is determined during the planning stage based on current and cable length; a larger cross-section minimises losses over long runs. Connectors may only be connected to counterparts from the same manufacturer, and they are crimped using the tool specific to that system. Neither of these is visible from the outside once the connection is complete, which is why the appropriate tool must be included in the order.
What the kits do not include
The complete PV kits consist of modules, an inverter and, depending on the kit, a storage unit. The mounting structure is not included in any kit, and DC solar cables are only included in certain balcony power plant kits (12 or 24 metres, depending on the kit), as both depend on the type of roof, roof pitch and cable route. Depending on the version, the balcony power plant sets come with either a Schuko connection cable or a Y-splitter, but never include a mounting bracket. A Hantech mounting bracket for the balcony railing is included with the substructure.
This is different for the flat-roof kits from K2 Systems: they include base profiles (Base Set), mounting brackets, end clamps and ballast supports in quantities suitable for 2, 4, 6, 8, 10 or 12 modules; from four modules upwards, they also include centre clamps and cable ties. The ballast blocks themselves are not included; the quantity required is determined by the planning for the specific roof.
Installation, connection and registration
A structural analysis determines whether the roof can bear the additional load, particularly in the case of a ballasted mounting system on a flat roof. To connect a photovoltaic system to the domestic electricity supply, contact a qualified electrician; your network operator will advise you on the applicable requirements. Legal requirements apply to registration with the network operator and in the market master data register; information is available from the network operator and the Federal Network Agency.
Frequently asked questions about assembly and installation
Does ACTEC offer assembly or installation services?
No. ACTEC supplies the materials for assembly, but does not provide an assembly or installation service. You must commission a specialist contractor of your choice to carry out the assembly and electrical connection.
Which substructure is suitable for my roof?
This depends on the type of roof covering. On a pitched roof, the rails are supported by roof hooks or anchor bolts; on a double-seam standing seam roof, the CF:x seam clamp is used; on trapezoidal sheet metal, the MiniRail and BasicRail 22 systems are used; and on a flat roof, the D-Dome 6.10 east-west mounting system with ballast is used.
Are the mounting structure and cables included in the complete PV kits?
Generally not. The kits contain modules, inverters and, where specified, the battery. The mounting structure is never included; solar cables are only included in certain balcony power plant kits, where they measure 12 or 24 metres depending on the kit; you should select both to suit your roof and cable route.
What cross-section do solar cables need?
Our range includes solar cables with cross-sections of 4 and 6 mm². The appropriate size depends on the current and the length of the cable run. For equipotential bonding, there is a green-and-yellow cable with a cross-section of 16 mm².
What tools do I need for ‘MC4’ connectors?
A crimping tool with the correct insert and locator, a wire stripper, a mounting spanner for tightening the screws, and a test probe. Stäubli also offers all these items together in a tool case for MC4 and MC4-Evo 2.
Can I connect the photovoltaic system myself?
For connection to the domestic mains supply, a qualified electrical contractor is the right person to contact; your network operator will tell you what you are permitted to do yourself. There are legal requirements governing registration with the network operator and in the market master data register; information on this is available from the network operator and the Federal Network Agency. It is best to clarify with this contractor which tasks you can carry out yourself beforehand.