Service models and technology at the string inverter level is vastly improved from where it was a few years ago. Earlier this week we looked at the value of choosing string inverters over central inverters for projects upward of 20 MW, thanks to 1,500-volt architecture, and then the nuances of approach among virtual centralized string and distributed string.
Choosing string means taking advantage of its positives as much as you can, which means design flexibility and maximizing uptime. If a string inverter or two has to come off line for maintenance, only a fraction of the generation of the system is affected compared to the large chunks connected to a central inverter.
Doubling down on this advantage, for distributed string projects, CPS America inverters come with a separable but integrated wiring box where all of the conductors go in and out. Sold together, every inverter comes with its mated wire box. Four bolts hold the wire box to the inverter body — they slide together with guide pins and one large electrical connector — leaving no wires to play with between the inverter and the wire box.
“If there is a problem with the inverter, 99 percent of the time, it will be in the inverter not the wiring box,” says Sarah J. Ozga, product manager North America for CPS America. “And what takes so much time when swapping out inverters is disconnecting the wires to remove it. So with the integrated but separable wire box, you never have to touch a wire — just leave the wires and conduits installed in the wire box, disconnect the inverter and slide in the new one in.”
An RMA swap of the inverter body takes only 15 minutes with this approach from CPS. Suddenly, having them dispersed all over the site doesn’t seem as daunting.
There are communication advantages across the market too that improve O&M while simplifying commissioning. Flex Gateway, for example, is a communication card added to just one inverter in the communication daisy-chain of up to 70 inverters. When the inverters are connected to a third-party monitoring system or even simply a router, the CPS Service team can remotely access the inverter for troubleshooting, to change the settings and even update firmware on the connected inverters. This will reduce truck rolls and get systems up and running faster than before.
— Solar Builder magazine