Article by Bryan Whitton, product manager at Darfon America
Contractors are continuously looking for ways to save time and effort on each solar installation. One method of doing so is purchasing preassembled components. While the layout of any array is typically unique to the site, installing the rails, wire management and the modules is exactly the same for each project. Purchasing preassembled components helps minimize work, improve consistency and lessen damage to the roof and waste.
There are a couple options for purchasing preassembled components when it comes to microinverters, in particular.
Microinverters with modules
One option is to purchase panels with pre-installed microinverters, known as AC modules. The microinverter and modules are assembled in the factory, rather than on the job site, and are usually sold through the panel manufacturer under one warranty for the integrated components. A preassembled module with a microinverter makes installation much faster. However, there are some drawbacks.
“Buying an AC module limits the panels from which you can choose, which can hurt budgets because panels are the most expensive component of a solar installation,” said Bryan Whitton, product manager at Darfon America. “Also, if the inverter fails, it’s likely both the module and the inverter will need to be replaced to preserve the AC module’s UL certification.”
Microinverters with racking
Due to the drawbacks of AC modules, some manufacturers have come to offer a different kind of marriage. Instead of integrating microinverters with modules, new solutions combine microinverters with racking.
For example, Darfon’s ACRak is a preassembled solution combining its microinverters and trunk cables with IronRidge’s XR rails at the factory. Like AC modules, this helps reduce installation time so contractors can move on to other projects, but with more flexibility. “The biggest advantage is having complete flexibility in module selection among any 60 or 72-cell module,” Whitton said. “Because the inverter can accept both the voltage and the power of larger modules, you have the luxury of selecting almost any module.”
The marriage also offers advantages in case of failure. “If an inverter needs to be replaced, you simply lift the module from the rails and remove the inverter,” Whitton explained. “After you replace the inverter, simply bolt the module back down. Nothing is changed except the inverter, which is a major time and money saver.”
Whitton said other advantages often overlooked concern logistics and how much wear and tear happens to the roof when installing components separately. “Installing the rails, trunk cables and inverters at the same time means much less traffic on a roof,” he said. “Also, logistics are improved because you are dealing with fewer part numbers. The ACRak specifically reduces expense and hassle in shipping and storage because its rails are only 85 in. long, which eliminates oversized packaging required for traditional rails that are more difficult to arrange on trucks.”
Getting the parts to the roof is also much easier, Whitton noted, because in many cases you can simply pass the preassembled solution to the roof from the ground, which means less time and ladder work. Also, because the rails and trunk cables are premeasured, there is little waste after the installation.
“Using a preassembled microinverter and racking system saves time, hassle and money,” Whitton said. “It’s a great way to make your business more efficient and profitable.”