In the previous year, the Clean Energy Council had suspended many accreditations and cancelled 51 accreditations. The majority of cases opened derived from the audits of the Clean Energy Regulator to inspect the quality and compliance of solar panel installation throughout the country. GSES has participated in the Clean Energy Regulator’s inspection scheme for many years and has come across all sorts of great, bad, and poor systems. This article will reveal some of the most frequent problems detected during our inspections and tips on enhancing solar installation so that installers can sleep soundly knowing they shall never encounter a compliance problem. Equally important, their clients are protected and satisfied.
Roofing Penetrations
When the photovoltaic array cable and the duct pass through tiles and steel roofs, there should be fit-for-purpose collar flashing, such as dektite, to prevent issues during solar power installation.
Improper Roofing Penetrations
In the example below, the cables pass through a roof without any dektite or flashing present. This improper pv panel installation could lead to water ingress into the sections, potentially causing significant damage to the entire system and surrounding components. To counter this, the installer needs to perform a reinstallation using a dektite and ultraviolet sealant. To make the penetration water-resistant, adding extra silicone to the penetration is advisable. The installer should also fit an appropriate cable gland on the end of the duct leading to the roof penetration to prevent further problems.
Correct Roofing Penetrations
The image below demonstrates the correct use of dektites and flashing on the roof penetrations in a rooftop solar panel installation. Proper protection against water ingress extends the system’s lifetime significantly.
Earthing Lugs and Weebs
The design and installation of the earthing system is crucial for the operation of the system. Issues with earthing can lead to fluctuations in electric current, fire hazards, damage to surrounding components, and a decrease in system efficiency.
Improper Earthing
In the image below we have a case where WEEB is not well installed thus the grounding of the appropriate panel is compromised. It should be fastened strongly on the panel to assume the electrical current as was observed with the WEEB.
The image below left shows that an earthing lug is sprayed, however, the lug is in direct touch with the panel surface. This in turn can lead to short circuits and hotspots showing on the panel, which leads to system damage and deterioration in performance.
Proper Earthing
An excellent earth design has each module ground or earthed. Fortunately, the present concept of using fiber optic links will not place in danger the earthing of any other module when one or more modules are removed from the system. All lugs and WEEBs should be installed to conform to the manufacturer’s requirements as well and should not be exposed to any deposits of moisture or, in other words, should be anti-corrosive.
It is therefore recommended that checks are made on all the mid-clamps and that earthing (WEEB) washers be used with all of them. It is necessary to be careful when placing the modules since the metal frame of the power supply may scratch the WEEB washer and thus reduce the efficiency of the currents when passing through the washer.
Cabling and Connectors
The faults associated with improper cabling terminations and connectors are one of the most widespread in photovoltaic systems. Cabling installation requires a proper duct where applicable as well as glands. We should not use a multi-hole gland for a single cable if it is exposing a hole.
These connectors, that are interconnecting the panels, should always be of the same type and model only. Mis-mate connectors increase the chances of the connectors coming apart which results in dust and water getting into the system, this eventually results in faults in the system as well as arcs being formed.
Improper Cabling
An improper connection between a duct and a gland can be seen in the image below with the possibility of water ingress into the duct. However, when an appropriate drain is provided at the lowest point of the duct the external cabling is at risk.
This image does not have a duct at all, which makes the cables suspended, hanging, and exposed.
Proper Cabling
In this case, good cabling will be well organized, sealed, labeled, and well-finished.
A good methodology ensures that:
- There is an inscription of the duct every two meters or so.
- Drains are made to be fitted at the duct’s lower point, and its lowest point is not at the switchboard or any conductor termination.
- The cabling on the roof of the particular modules is not loose and is not in contact with the roof surface.
- No new holes have been made in the enclosures including the base also. This is something that is frequently done, which leads to deterioration of the weather resistance of the chosen enclosure.
- The gland doesn’t have more cables passing through it than the number of holes it has; extra holes are closed by a plug supplied by the manufacturer.
Isolators
Isolators should be installed in compliance with the existing standards of the manufacturers, their relevant ratings, and AS/NZS 5033:2021 for effective solar pv system installation.
Improper Isolator Installation
If not done, the following may occur even if the isolator is mounted below the panel as shown below. If water enters the components, the components will fail; in the worst scenarios, the entire system will be on fire. Installers should also ensure that there are no gaps between the isolator and the duct – more importantly, the entry point of the isolator should not be at the bottom of the duct because these ducts can fill up with water. The isolator should also be well closed properly when one is replacing the cover upon installation of the system.
Proper Isolator Installation
The standard isolator installation is in the shade (often at the bottom of panels. But it covers as described in AS/NZS 5033 is also allowed), with measures being properly taken. So, it can help avoid intrusion of weather. Ideally, it should be well located in a suitable environment, and the different parts of the skeleton must be well labeled for easy identification. So, the following example of a correctly installed isolator As shown below the isolator is installed in a way that its rubber surface faces upwards.
Signage
Many times it is overlooked that signage is not needed especially for the residents but is important for the next traders in the site and the emergency services. A photovoltaic reflector tells you right away that there is a system to enclose if needed; a DC cabling caution put where required by guidelines could save a nasty encounter for whoever is occupying the roof space.
Improper Signage
The 70mm green PV reflectors often found and bought in the market do not conform to AS/NZS 5033:2021 5. 4. The below-left reflector is missing an indication of the isolation method (eg ‘DP’). This reflector right cannot be expected to survive the lifetime of the system; the installer even on the first move will call for a change.
Proper Signage
A lot of requirements for postings are currently in India, and they can be generally traced in the most recent editions of AS/NZ 5033, AS/NZ 4777, and AS/NZ 3000. It is also among the most frequent areas, where installers are pulled up. It does not matter at all that if the neutral wire is not labeled in the switchboard, the points which cut the connection are at the wrong site or the plan lacks necessary information, like the address, then there is much to take note of. Nevertheless, an exemplary system will have all the required and necessary signage that will mean that any further work on or in the vicinity of the system will be as safe as it can be. The below picture is also a good example of signage.
Inverter Installation Location
Depending on the IP rating of the inverter, it should be installed in an appropriate location; it should not be located in an area where it comes under direct sunlight for most parts of the day. Were installed in a place in direct sunlight, they would degrade much faster to a point where water resistance could be an issue or even where maintenance can only be done and damage the enclosure. It should be mounted in a well-vented place, and away from the sunlight as illustrated in the following picture.
Conclusion
Solar installation is a debatable topic because, when things go wrong, it is ugly to behold if shortcuts are taken. From simply needing to swap out a part to having ceilings that are ruined by an unsealed roof, there are especially preventable faults that cost money and bring inefficiency and lack of durability to systems. The same can be said for installations; consistent installation problems pose a threat to accreditation, therefore there is a need to be extra hard on their instalments.
FAQS:
What are the most common mistakes during solar panel installation?
Common mistakes include improper roofing penetrations, incorrect earthing, poor cabling, and incorrect isolator installation.
How can I ensure proper earthing during solar power system installation?
Use appropriate earthing lugs and WEEBs as per the manufacturer’s guidelines and avoid exposure to moisture.
What should be considered for proper cabling in solar PV system installation?
Ensure organized cabling with proper labeling, adequate ducting, and avoid loose connections or unnecessary holes in enclosures.
Why is isolator installation important in a solar installation?
Proper isolator installation prevents system failures and fire hazards. It should comply with AS/NZS 5033 standards.
What role does signage play in solar panel system installation?
Proper signage ensures safety for future workers and emergency services, providing critical information about the solar system layout and connections.
