Solar SlowPump Technical Data
The Dankoff Solar SlowPump was the world's first commercially available low power solar pump. Developed by Windy Dankoff in 1983, it has thousands of installed units worldwide over its nearly 40 year life.
Produced in a wide range of sizes, the Solar SlowPump is used to draw water from shallow sources and push it as high as 450 vertical feet through miles of pipeline. Designed for reliability and maintainability, wear parts typically last 5-10 years, with an overall life expectancy of 15-20 years before rebuild.
Construction & features
- Rotary vane mechanism (positive displacement) made of forged brass, carbon-graphite, and stainless steel
- NSF approved for drinking water
- Handles sea water and dissolved minerals
- Survives most freezes
- Permanent magnet, DC motor
- AC models use a low-surge PM motor that greatly reduces starting surges, inverter, and wire size requirements
- Installation and Service Manual is highly detailed and illustrated
Filtration requirement
- This pump cannot tolerate dirt, so water must be filtered clear. Failure to use an approved filtration unit will void the warranty of the pump.
- If water is very dirty, improve the source or consider a dirt-tolerant model: SolarForce, SunCentric, or SolaRam.
Solar-direct applications (PV-direct / non-battery)
- Rated power of the PV array must meet the Watts listed in the PV Watts column of the performance chart
- The Dankoff DC Controller increases system performance nearly 30% over the course of one year and is required to start and run in low light conditions
Mechanical characteristics
- 1300 models — 5 ¾ × 17 ⅜ in (14.61 × 44.14 cm), ½ in female fittings, 12 lb (5.45 kg)
- 1400 models — 6 ½ × 18 ¾ in (16.51 × 47.63 cm), ½ in female fittings, 25 lb (11.34 kg)
- 2500 models — 5 ¾ × 17 ⅜ in (14.61 × 44.14 cm), ¾ in male fittings, 13 lb (5.9 kg)
- 2600 models — 6 ½ × 18 ¾ in (16.51 × 47.63 cm), ¾ in male fittings, 29 lb (13.16 kg)
Warranty
- 1 year against defects in materials and workmanship
Performance chart — 1/5 horsepower models
Total Lift = vertical distance from water surface to outlet plus pipeline friction loss. Performance at 15 or 30 V (PV-direct); for battery subtract 20% from flow & watts; 24 V pump may be run at 12 V to yield ½ flow at ½ watts. Actual performance may vary ±10%. PV-direct voltage 12/24/48 VDC; inverted (AC) 115 VAC.
| Total Lift | Model 1322 | Model 1310 | Model 1308 | Model 1304 | Model 1303 | Model 2505 | Model 2507 | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ft | m | GPM | LPM | PV W | GPM | LPM | PV W | GPM | LPM | PV W | GPM | LPM | PV W | GPM | LPM | PV W | GPM | LPM | PV W | GPM | LPM | PV W |
| 0-20 | 0-6 | 0.51 | 1.93 | 40 | 0.92 | 3.48 | 40 | 1.25 | 4.73 | 40 | 1.75 | 6.62 | 45 | 2.5 | 9.46 | 65 | 3.25 | 12.3 | 70 | 4 | 15.14 | 80 |
| 40 | 12 | 0.51 | 1.93 | 45 | 0.92 | 3.48 | 50 | 1.25 | 4.73 | 65 | 1.75 | 6.62 | 65 | 2.5 | 9.46 | 80 | 3.23 | 12.23 | 75 | 3.95 | 14.95 | 100 |
| 60 | 18 | 0.51 | 1.93 | 45 | 0.89 | 3.37 | 60 | 1.2 | 4.54 | 70 | 1.68 | 6.36 | 80 | 2.44 | 9.24 | 90 | 3.15 | 11.92 | 110 | 3.9 | 14.76 | 130 |
| 80 | 24 | 0.49 | 1.85 | 50 | 0.88 | 3.33 | 65 | 1.2 | 4.54 | 80 | 1.64 | 6.21 | 90 | 2.36 | 8.93 | 110 | 3.1 | 11.92 | 130 | 3.9 | 14.76 | 150 |
| 100 | 30 | 0.49 | 1.85 | 65 | 0.88 | 3.33 | 70 | 1.2 | 4.54 | 85 | 1.64 | 6.21 | 100 | 2.33 | 8.82 | 130 | 3.08 | 11.66 | 155 | 3.85 | 14.57 | 180 |
| 120 | 36 | 0.48 | 1.82 | 65 | 0.88 | 3.33 | 75 | 1.2 | 4.54 | 90 | 1.62 | 6.13 | 110 | 2.33 | 8.82 | 160 | 3.02 | 11.43 | 180 | 3.8 | 14.38 | 210 |
| 140 | 42 | 0.47 | 1.78 | 70 | 0.88 | 3.33 | 80 | 1.2 | 4.54 | 90 | 1.6 | 6.06 | 125 | 2.27 | 8.59 | 160 | 2.92 | 11.05 | 210 | 3.65 | 13.82 | 245 |
| 160 | 48 | 0.47 | 1.78 | 85 | 0.87 | 3.3 | 95 | 1.2 | 4.54 | 110 | 1.6 | 6.06 | 140 | 2.21 | 8.36 | 180 | 2.85 | 10.79 | 235 | — | — | — |
| 180 | 54 | 0.47 | 1.78 | 85 | 0.86 | 3.26 | 100 | 1.18 | 4.47 | 120 | 1.57 | 5.94 | 150 | 2.11 | 7.99 | 190 | — | — | — | — | — | — |
| 200 | 60 | 0.45 | 1.7 | 100 | 0.85 | 3.22 | 110 | 1.16 | 4.39 | 130 | 1.56 | 5.91 | 165 | 2.03 | 7.68 | 220 | — | — | — | — | — | — |
| 240 | 72 | 0.44 | 1.67 | 120 | 0.84 | 3.18 | 130 | 1.14 | 4.31 | 150 | 1.54 | 5.83 | 190 | 1.96 | 7.42 | 235 | — | — | — | — | — | — |
| 280 | 84 | 0.41 | 1.55 | 130 | 0.81 | 3.07 | 150 | 1.12 | 4.24 | 170 | 1.51 | 5.72 | 220 | — | — | — | — | — | — | — | — | — |
| 320 | 96 | 0.41 | 1.55 | 150 | 0.79 | 3 | 170 | 1.1 | 4.16 | 195 | 1.48 | 5.6 | 245 | — | — | — | — | — | — | — | — | — |
| 360 | 108 | 0.41 | 1.55 | 170 | 0.76 | 2.88 | 195 | 1.05 | 3.97 | 220 | — | — | — | — | — | — | — | — | — | — | — | — |
| 400 | 120 | 0.4 | 1.51 | 190 | 0.73 | 2.76 | 220 | 1 | 3.79 | 250 | — | — | — | — | — | — | — | — | — | — | — | — |
| 440 | 132 | 0.39 | 1.48 | 210 | 0.7 | 2.65 | 250 | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| 480 | 146 | 0.25 | 0.95 | 260 | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| 520 | 158 | 0.25 | 0.95 | 310 | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| 560 | 170 | 0.2 | 0.76 | 340 | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
Performance chart — 1/2 horsepower models
Motor ½ horsepower. PV-direct voltage 24/48 VDC; inverted (AC) 115 VAC. Actual performance may vary ±10%.
| Total Lift | Model 1408 | Model 1404 | Model 1403 | Model 2605 | Model 2607 | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ft | m | GPM | LPM | PV W | GPM | LPM | PV W | GPM | LPM | PV W | GPM | LPM | PV W | GPM | LPM | PV W |
| 0-20 | 0-6 | 1.92 | 7.27 | 110 | — | — | — | 3.64 | 13.78 | 130 | — | — | — | 6.2 | 23.47 | 185 |
| 40 | 12 | 1.9 | 7.19 | 120 | — | — | — | 3.6 | 13.63 | 150 | — | — | — | 6.1 | 23.09 | 240 |
| 60 | 18 | 1.88 | 7.12 | 130 | — | — | — | 3.61 | 13.66 | 170 | — | — | — | 6.09 | 23.05 | 250 |
| 80 | 24 | 1.88 | 7.12 | 140 | — | — | — | 3.5 | 13.25 | 200 | — | — | — | 6.04 | 22.86 | 290 |
| 100 | 30 | 1.85 | 7 | 150 | — | — | — | 3.5 | 13.25 | 220 | — | — | — | 6.04 | 22.86 | 330 |
| 120 | 36 | 1.83 | 6.93 | 160 | — | — | — | 3.43 | 12.98 | 235 | — | — | — | 6 | 22.71 | 355 |
| 140 | 42 | 1.82 | 6.89 | 170 | — | — | — | 3.43 | 12.98 | 255 | — | — | — | 6 | 22.71 | 390 |
| 160 | 48 | 1.82 | 6.89 | 185 | — | — | — | 3.43 | 12.98 | 280 | — | — | — | 5.93 | 22.45 | 430 |
| 180 | 54 | 1.81 | 6.85 | 200 | — | — | — | 3.4 | 12.87 | 300 | 3.35 | 12.68 | 350 | 5.83 | 22.07 | 470 |
| 200 | 60 | 1.81 | 6.85 | 215 | — | — | — | 3.35 | 12.68 | 320 | 3.33 | 12.61 | 370 | 5.8 | 21.95 | 500 |
| 240 | 72 | 1.77 | 6.7 | 235 | — | — | — | 3.38 | 12.79 | 360 | 3.3 | 12.49 | 415 | 5.75 | 21.76 | 585 |
| 280 | 84 | 1.79 | 6.78 | 260 | — | — | — | 3.3 | 12.49 | 405 | 3.25 | 12.3 | 465 | 5.59 | 21.16 | 675 |
| 320 | 96 | 1.72 | 6.51 | 290 | 1.66 | 6.28 | 320 | 3.3 | 12.49 | 450 | 3.2 | 12.11 | 515 | — | — | — |
| 360 | 108 | 1.75 | 6.62 | 310 | 1.66 | 6.28 | 350 | 3.2 | 12.11 | 520 | 3.16 | 11.96 | 565 | — | — | — |
| 400 | 120 | 1.69 | 6.4 | 330 | 1.64 | 6.21 | 390 | 3.2 | 12.11 | 545 | — | — | — | — | — | — |
| 440 | 132 | 1.69 | 6.4 | 355 | 1.62 | 6.13 | 430 | 3.1 | 11.73 | 610 | — | — | — | — | — | — |
| 480 | 146 | 1.7 | 6.43 | 380 | — | — | — | — | — | — | — | — | — | — | — | — |
| 520 | 158 | 1.61 | 6.09 | 400 | — | — | — | — | — | — | — | — | — | — | — | — |
| 560 | 170 | 1.67 | 6.32 | 435 | — | — | — | — | — | — | — | — | — | — | — | — |
Transcribed from the official Dankoff Solar technical data sheet. Subject to technical changes — the PDF is the authoritative version. Not sure this is your pump? The calculator will match one to your system.
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