Array Yield

What you can build

• Send a cleaning crew when the whole array dulls

  Every inverter on the roof produces less than NASA POWER's irradiance predicts, and the gap has held for the days you set. The operator drafts one cleaning work order in MaintainX naming the array asset and the gap.

  With Modbus TCP, NASA POWER, MaintainX

• Find the one input that fell behind

  Model 160 shows one MPPT input's DC power trailing the others on the same inverter under the same sky. The operator drafts an inspection work order in Fiix naming the inverter and the input.

  With Modbus TCP, Fiix

• Watch a fleet through the vendor cloud

  Sites without Modbus reach report through SolarEdge or Enphase site energy instead. The operator runs the same comparison per site and drafts work orders in UpKeep, within each vendor's rate limits.

  With SolarEdge Monitoring API, Enphase API, UpKeep

• Tell weather from dirt

  Production fell, but Open-Meteo's cloud cover and the NWS forecast say the sky did too. The operator records the day as weather and proposes nothing, so Limble never fills with work orders for clouds.

  With Open-Meteo, Weather & Severe Alerts, Limble CMMS

Requirements

• Inverters that speak SunSpec Modbus over TCP or RTU, reachable from a gateway, found by the SunS marker at base address 0, 40000, or 50000
• A CMMS connector to receive the work order: MaintainX, Fiix, UpKeep, or Limble, with each array registered as an asset
• An irradiance source: NASA POWER hourly at the site's coordinates, or Open-Meteo with the array's tilt and azimuth set
• A tolerance and a run of days set by you before a lag becomes a proposal; the operator ships no default

Authentication

Reads inverters through the Modbus reach of your gateway or the vendor API credentials you attach, and irradiance from public feeds. It writes only to the CMMS, only after approval.

Limits

• Expected yield comes from a gridded irradiance model, not a rooftop pyranometer. A local sensor read over Modbus, where you have one, replaces it
• NASA POWER hourly data runs to near real time; the day just ended may not be in it yet. The comparison waits rather than guessing
• A string shaded at a fixed hour looks like a dirty one. The operator names the lagging hours; the person who approves makes the diagnosis
• Open-Meteo's free tier is non-commercial, under CC BY 4.0, and capped below 10,000 calls a day; a commercial site needs a subscription

Questions and answers

What does the maintenance lead approve?

A work order draft: the asset, the inverter and input, measured energy against expected for the days in question, the irradiance and temperature used, the inverter's operating state, and the reason class. The lead approves, edits, or declines. One approved draft becomes one work order.

What record is left after a work order is created?

The work order in your CMMS carries the gap, the hours it lagged, and the readings behind it. The operator keeps the draft, who approved it, when it was created, and the yield before and after, so a cleaning that changed nothing is visible.

Does it ever change the inverter?

No. It reads SunSpec models and never writes a register. Curtailment, limits, and settings stay with your installer and the vendor tools. Its only write is a work order, and only after a person approves it.