Why is cabling important
?Efficiency: High-quality cables and correct connections minimise energy losses
Safety: Proper installation protects against short circuits, overheating and electrical hazards.
Durability: Well-laid cables and connections extend the service life of your system.
Step-by-step guide
1. preparation and choice of material
Cable types:
Use direct current cables (DC cables) specially developed for PV systems with UV resistance and high insulation
.Standard household cables are suitable for alternating current connections (AC cables)
Cable cross-section:
Select the cross-section based on the power of the solar modules and the cable length. Example: 4 mm² or 6 mm² for DC cables for standard systems.
Connections:
Use weatherproof MC4 connectors for solar modules and robust terminals for the connection to the inverter.
Tip: Choose cables with the shortest possible length to minimise energy losses.
2. cabling of the solar modules
Series connection (series connection):
Connect the positive terminal of one module to the negative terminal of the next
This circuit increases the voltage while the current remains the same.
Parallel circuit:
Connect the positive poles of all modules together and the negative poles as well.
This circuit increases the current while the voltage remains the same.
Protection against reverse polarity: Ensure that the polarity is connected correctly to prevent damage to the inverter.
Tip: For larger systems, you can use a combination of series and parallel connection.
3. connection with the inverter
DC input:
Connect the cables of the solar modules to the DC input of the inverter.
Use the MC4 connectors for this, which ensure a secure and weatherproof connection.
AC output:
Connect the AC output of the inverter to the power grid or a battery storage system.
Earthing: Install an earthing bar to safely discharge electrical surges.
Tip: Always follow the inverter manufacturer's instructions for the cabling.
4. Install protective measures
Overvoltage protection:
Install surge protection devices to protect the system from damage caused by lightning strikes or voltage peaks.
Fuse boxes:
Place fuses between the modules and the inverter and between the inverter and the power grid.
Cable protection:
Use cable ducts or protective conduits to protect the cables from the weather and mechanical damage.
5. Testing and commissioning
Cable testing:
Test all connections with a multimeter to identify short circuits or open circuits.
Monitoring system:
Activate the monitoring system to check the system's performance in real time.
Safety check:
Have the installation approved by a certified electrician before putting the system into operation.
Tip: Carry out a test run in full sunlight to check the maximum output.
Avoid common mistakes
Wrong polarity: Reverse polarity connections can damage the inverter. Ensure that the plus and minus are connected correctly.
Undersized cables: Cables that are too thin can cause energy loss or overheating.
Loose connections: Check all connections to avoid voltage fluctuations or malfunctions.
Conclusion: safety and efficiency through correct cabling
Well-planned and properly executed cabling is crucial for the success of your PV system. With high-quality materials, the right protective measures and careful installation, you can ensure that your system works efficiently and safely.
Learn more about installing and maintaining your solar system in our guides!