These systems comprise grid-connected, stand-alone and hybrid, incorporating grid and battery back-up.
Grid connect systems enable surplus power not used by the household to be fed back into the main power grid. When the panels are not producing power at night or reduced output on cloudy days, power is drawn from the grid.
Hybrid systems incorporate connection to the grid as well as battery storage. Surplus power generated charges the battery. Once the battery is fully charged, excess power is fed into the grid. When the solar panels are not generating power, the battery supplies power until its charge level is low, when the grid resumes supply.
Stand-alone systems are not connected to the grid. Any surplus power generated by solar PV is stored in a battery for later use.
Maintaining Solar PV systems
If your solar PV system has been properly installed and well maintained, it should last many years. It should be checked annually or according to the manufacturer’s recommendations by an accredited solar installer or licensed electrical contractor.
Never attempt electrical repairs yourself.
Regular maintenance checks will ensure correct operation, system performance is maintained and safety for occupants and electrical workers working on the grid.
Problems that may occur include:
- water seepage;
- deterioration of cable insulation;
- corrosion;
- damage from vermin, storms and vandals; and
- faulty components.
Maintenance should ensure:
- cooling vents are clear of debris;
- panels are clean, not discoloured and free of cracks or chips;
- panels and supporting frames are secured and free of debris;
- switches are free of defects;
- no parts have deteriorated or corroded;
- the wiring’s insulation has not deteriorated or been damaged;
- fittings and cables at both the panels and inverter are securely attached;
- the inverter’s display panel is checked for any faults;
- emergency procedures for shut down and isolation are clearly displayed;
- access to isolator switches is not impeded; and
- the battery storage system (if it is part of your system) is in good working order.
The solar system should be shut down before anyone accesses the rooftop, gutters or the solar panels.
Shutting down your Solar PV system
If you need to shut down the solar PV system, follow the procedure located at the inverter or on the main switchboard. You may damage the system by not following the correct shutdown procedure. Do not attempt to turn off a solar power system if any of its components are damaged. Contact your licensed electrical contractor or installer for advice.
Solar panels will continue to generate electrical voltage during the day, even if the main power has been disconnected or the system has been shut down.
Safety on roofs and in ceiling spaces
Serious electrical safety risks are present in ceiling spaces and on roof tops. It is best to leave all solar power system maintenance to electricians and installers. If you do any general maintenance activity near solar power systems, take particular care around the supply cables running from the panels on the roof to the inverter unit, as they will be live when the solar panels are generating electricity. If you go up into your ceiling space, remember that even if you first turn off the main power switch at the switchboard, the cables from the solar power system to the inverter, and the main power supply entering your house from the street to the switchboard will remain energised.
Whenever entering or moving around your ceiling space, treat all wiring as live (energised) at all times.
DC isolating switches
Australian Standard AS/NZS 4417.2:2018 require DC isolating switches used in solar PV installations to comply with a Level 3 certification under the national Electrical Equipment Safety System (EESS).
At the time of installation, DC isolating switches must have a valid Certificate of Conformity confirming the product complies with Australian Standard AS 60947.3:2018. The brand and all relevant models must be registered to the responsible supplier in the EESS national database and be marked with the Regulatory Compliance Mark (RCM).
Recalls
Fires caused by faulty DC isolator switches used on solar power systems have prompted the following brands to be recalled:
- AVANCO;
- SPM;
- NHP;
- Gen3;
- PVPower;
- ISO Max;
- HGN4
You can check whether your isolator switch has been recalled by checking its brand and model number under the electrical category at Product Safety Australia.
Where required, a DC isolator is installed adjacent to the PV array and adjacent to the inverter. All the DC isolators will need to be verified by a licensed electrician and in accordance with relevant Standards. If any have been recalled, follow the shutdown procedure, stop using the system immediately and call your licensed electrical contractor or installer. If you are unsure about the brand of isolator switch you have, contact your installer.
