iOS ยท Utility scale solar field toolkit

FieldWatt

The offline reference and toolkit for the people who keep solar farms running: commissioning and O&M technicians on 1500 volt DC plants. NEC calculators with worked steps and citations, cross vendor inverter fault codes, tracker procedures, PLC and SCADA and protection references, and site paperwork that becomes clean PDFs. Built for plants with zero cell signal: everything works offline, forever.

Now on the App Store

One app instead of a truck full of binders

The solar industry never standardized its field knowledge. FieldWatt consolidates it and puts it in your pocket, no signal required.

๐Ÿงฎ NEC calculators

Max and min string sizing, conductor ampacity with derates, fuse and OCPD limits, voltage drop, insulation resistance thresholds. Every result shows the formula, the worked steps, and the code citation for your selected NEC year.

๐Ÿ“š Cross vendor fault codes

SMA Sunny Central, Sungrow, and TMEIC central inverter fault codes with the safe response for each, plus combiner O&M, NEXTracker and Array Technologies procedures, and ANSI protection device numbers.

๐Ÿ–ง The controls layer

The hard to find stuff: Modbus and RS 485 troubleshooting, register map gotchas, DNP3, SunSpec, PLC status lights, Ignition tag quality, power plant controller behavior, and how to tell a real fault from a comms artifact.

๐ŸŒณ Guided troubleshooting

Decision trees for an inverter offline, an underperforming block, a ground fault, and a device that dropped out of SCADA. Safety critical findings render red with a stop work posture, never a blind reset.

๐Ÿ“‹ Site paperwork to PDF

LOTO permits, energized work permits, switching orders, JHAs, commissioning records, tracker PM, work orders, and safety checklists. Photos, signatures, and crew sign in, autofilled from your company and site profiles.

๐Ÿงพ Receipt tracker

Scan a receipt in the truck: on device OCR reads the vendor, amount, date, and category, tags who sent it in and the job number, and emails a clean PDF to the office and to you when signal returns.

๐Ÿ“ต Offline by design

Solar farms sit in fields with no coverage. Every reference, calculator, form, and tree ships inside the app. Outgoing email queues until you find signal.

๐Ÿงค Glove and sun friendly

A bright high visibility theme for direct sunlight, a dark theme for early switching, big tap targets, big readable numbers, minimal typing.

๐Ÿ”’ 100% private

No account, no server, no analytics, no ads, no tracking. Your site data stays on your device. The only network use is the App Store and the emails you choose to send.

FieldWatt is a field aid, not a substitute for the NEC, NFPA 70E, the site PE stamped drawings, the authority having jurisdiction, or manufacturer manuals. Safety critical faults require a qualified person.

Crew Site Log: know who is on site, without a subscription

FieldWatt logs arrivals and departures automatically. Each event goes straight to an endpoint your company owns, so the record lives in your Google account rather than on anyone else’s server. No per seat crew tracking subscription, and no vendor holding your timesheets.

📱 It works with no signal

Events queue on the phone when there is no coverage and arrive batched, oldest first, once the technician gets back in range. A basement, a substation yard or a roof with no bars does not lose the record.

📧 Four ways to receive it

Instant email alerts through a free Google Apps Script, a Google Sheet timesheet that fills itself in, Zapier if you would rather not touch code, or the live dashboard. Pick one and ignore the rest.

🔑 The data is yours

The automation runs under your own Google account, ideally a company one so it survives personnel changes. ThrasherApps never receives, stores or sees a single arrival record.

The complete guide walks through every screen and every option end to end, including all four automation recipes, the security notes for your endpoint URL, how to run the first test properly, and what to do when something looks wrong. It is written to be reread rather than skimmed once.

The dashboard reads your crew’s log straight from your own Google automation and keeps nothing except in your browser. It needs the Recipe 4 version of the script, covered in Part 6 of the guide.

More field toolkits

Same idea, built for other trades: everything bundled, fully offline, no account and no tracking.

LoopWatt

Fire alarm and life safety. NFPA 72 inspections that become authority ready PDFs, battery calculations.

App Store โ†’