Inside the SolarEdge Nexis and Nexis IslandDER

You’ve probably felt the pain of a battery job that eats more hours than it should: extra SKUs to track, a backup subpanel to build out, circuits to relocate. In a recent webinar, officially titled “The Power You Deserve,” BayWa r.e. brought together SolarEdge and ConnectDER to walk through the Nexis battery system and the Nexis IslandDER. You can watch the full session or read the key takeaways below. Cameron Stewart (SolarEdge’s principal product manager) and Kevin Cool (ConnectDER’s regional sales manager for the Southwest) covered a lot of ground, and most of it comes down to cutting exactly that kind of friction out of your install. 

Fewer parts on the wall, less time on the job

Nexis runs on four components:

• Inverter
• Nexis Link
• Battery blocks
• Nexis IslandDER, for backup

Each battery block gives you 4.9 kWh nominal capacity (4.65 kWh usable) with 3.5 kW of continuous charge and discharge. Stack up to four blocks per link for 19.6 kWh, attach up to four links per inverter, and you can scale a single inverter up to 78.4 kWh, from a small starter system to a full home setup, without switching hardware families.

The blocks connect through what SolarEdge calls Simple Click: two mechanical plungers lock in the DC wiring, communication wiring, and physical mounting in one motion. SolarEdge’s spec sheet puts stack assembly at under 10 minutes, and Stewart put a full battery install, wiring and commissioning included, at 15 to 20 minutes. Either way, the connection is forgiving enough that your newest hire and your most seasoned electrician get the same result. That’s real money back in your day.

You’re also not locked into a symmetrical stack. Six blocks can be three-and-three, four-and-two, whatever fits the wall in front of you. And when a customer wants more capacity down the line, you place a new stack next to the existing one and link them together. No touching the original conduit or AC wiring, no redoing work you already did right the first time.

One inverter that adapts to the job, not the other way around

SolarEdge moved to a single SKU for the Nexis inverter, and this is the kind of change that actually shows up on your bottom line. You set the power class (anywhere from 3.8 kW to 13 kW) at commissioning instead of ordering a pre-labeled unit for each job. That means you’re not stuck stocking a shelf of SKUs by power class, and you never show up to a site with the wrong inverter in the truck.

Backup output is separate from that programmed class: the inverter delivers 14.5 kW in backup mode no matter how you’ve set it for grid-tied operation, so you don’t have to plan around a lower number. Nexis is also backward compatible with SolarEdge’s P-series and S-series optimizers, so if you’re swapping a HomeHub for a Nexis, you’re not touching the roof.

You’ve also got AC coupling available if a customer already has a HomeHub inverter and would rather leave it in place.

Right-sizing backup without the guesswork

A useful rule of thumb to use for customer conversations is: Locked rotor amps determine whether your customer needs a partial or full home backup. Past three blocks, you’re adding runtime and capacity, so you can size confidently instead of overselling.

• One battery block: 62A of LRA, partial home backup
• Two battery blocks: 124A of LRA, partial home backup
• Three or more battery blocks: 185A of LRA, full home backup, enough to run sump pumps, well pumps, and a five-ton AC unit

Past three blocks, you’re adding runtime and capacity, not surge capability, so you can size confidently instead of overselling.

A typical whole-home backup build:

• Nexis inverter
• Nexis Link
• Three Nexis battery blocks
• Nexis IslandDER
• 80A breaker

The IslandDER: whole-home backup without building a subpanel

The Nexis IslandDER is a joint product with ConnectDER, built on ConnectDER’s 15 years making meter socket adapters. It installs behind the customer’s utility meter as a microgrid interconnection device, so you skip the critical load panel, skip relocating circuits, and skip pulling new cable runs to a backup subpanel. That’s hours off your install and one less thing that can go sideways on the job.

Two details are worth knowing before you’re on a roof or in a garage explaining it to a customer. First, the thermal management is entirely passive: a ceramic heat sink with no fans and no moving parts, rated to pass 200 amps through a housing about the size of a grapefruit. Fewer moving parts means fewer service calls down the road. Second, the IslandDER talks to the inverter over a straight Cat 5/RJ45 connection instead of routing through a separate control box, and you can run that cable out either side of the unit depending on how the job is laid out.

If the utility hasn’t approved behind-the-meter installation yet, you’re not stuck: install the IslandDER in a secondary meter can and splice it into the main service. ConnectDER keeps a running list of utility approvals and expected approval dates, so you can check before you quote. 

Built to handle whatever the site throws at it

Nexis is built to handle a wide range of job sites:

• Operating range of -4°F to 131°F, with power curtailing above 40°C to manage heat
• Airflow requirement of just 63 cubic feet
• Three variable-speed fans running at 33% capacity for redundancy: if one fails, the other two step up to 50% each, and the system flags it for you
• Elevation rated to 3,000 meters, about 9,800 ft, which covers nearly every install site in the continental US
• Resistive heating mats inside idle battery blocks for cold-climate jobs, since LFP cells shouldn’t cycle cold

That range means you can install with confidence in most US climates without a separate spec sheet for every region.

Your customer’s warranty includes:

• No cycle life limit on the battery
• 10-year system warranty
• 25-year optimizer warranty for residential jobs
• 12.5-year warranty on the IslandDER, with an expected service life of 20 to 25 years given the passive thermal design

Get it from BayWa r.e.

Nexis and the Nexis IslandDER are both in stock now. Reach out to your account manager or check the webstore for current pricing and availability to start quoting jobs with fewer parts, less wiring, and a cleaner finish for your customers.