Where the numbers come from
Every figure on this site is traceable. We do not publish a number we cannot name a source for. This page lists every source we use, what we take from it, and how you can verify it yourself.
Primary data sources
NASA POWER
power.larc.nasa.govMonthly solar irradiance (kWh/m²/day) and air temperature, per city, all our climate guides use the same city-level monthly figures — not an annual average.
FAO (UN Food & Agriculture Organization)
fao.orgCrop water requirements, irrigation scheduling and leaching fractions. Used for maize, rice, tomato and greenhouse watering guides.
WHO / USGS salinity ladders
usgs.govSalinity thresholds by crop. The brackish-water guide uses these to separate "usable", "slightly saline" and "needs treatment" water.
USDA-ARS (USDA Agricultural Research Service)
ars.usda.govWindmill pump field measurements. The windmill replacement guide compares against USDA-ARS published flow figures, not a marketing sheet.
IEC / manufacturer test curves
factory dataH-Q performance curves come from the factory test bench. Models with measured curves are marked ● in the Pump Finder; the rest use the standard H∝Q² approximation and say so.
Franklin Electric AIM manual
franklinwater.comFailure modes for vertical turbine and submersible pumps — backspin, upthrust, water hammer — quoted in the check valve guide.
Standards we test against
| ISO 2858 / ISO 20361 | Performance test code for liquid pumps — the method factory curves are measured to. |
|---|---|
| IEC 60335-2-41 | Safety of pump units for water supply — the standard the controllers are built against. |
| IEC 61727 / IEC 62102 | Photovoltaic system performance and safety, relevant to array sizing and panel VOC limits. |
| IEC 62105 | Protection against lightning — basis for the surge-protection guide. |
| 1.3× panel rule | Not a standard but our default: every array example sizes panels at 1.3× pump power to absorb inverter and wiring losses. |
How we handle model numbers
Catalogue model names change — series get renamed, decimals get inserted, AC/DC variants gain
an -A/D(HV) suffix. When an article still referenced an older form we replaced it
with the current catalogue name and noted it, rather than deleting the reference or leaving a
number a buyer could not search for.
Our editorial rules
- No invented model numbersEvery model on this site exists in the current factory catalogue. If a series has been renamed, the article says which model replaced it.
- No invented parametersFlow, head, voltage and power are copied from the catalogue, not estimated. Where we extrapolate, we say it is an approximation.
- Worst month, not averageSolar sizing uses the worst month of the year. An annual average hides exactly the season that breaks a pump.
- 1.3× is the defaultArray examples size panels at 1.3× pump power unless the guide gives a reason to change it.
- Corrected in publicWhen a spec error is found, the article is updated and the fix noted here — not quietly deleted.
Something look wrong?
If a number on this site looks wrong, tell us and we will check it against the catalogue and correct it in public.
Ask us for the source