Silentwind · Wind generator

Silentwind Pro

The Silentwind is a small three-blade wind generator for yachts and off-grid sites, made in Guimarães, Portugal, by Kab Connect (older documents name Rulis Eléctrica; in Germany the first units were sold under the spreco name). The head holds only a three-phase permanent-magnet generator: its AC runs through a slip ring to an external charge controller that rectifies, charges the batteries and brakes the rotor, and every version turns hand-laminated carbon blades on a 1.15 m rotor. Four generations share this layout: the first Silentwind (2010–2012, 12 and 24 V), the Silentwind 400+ in a second (2012–2015) and third generation (2015–2019), and since 2019 the Silentwind Pro, which keeps the 400+’s rated output of 420, 450 or 500 W at 12, 24 or 48 V. Stators, generator heads and charge controllers are voltage-specific, so give voltage and serial number when ordering; the old Hybrid 600 and Hybrid 1000 controllers work only with the first two generations.

Manuals & documents

The links go to Silentwind’s own documents — some as archived copies of pages the maker has since taken down. We host no manuals or drawings.

Wear parts & part numbers

PartOEM numberAlso fitsNote
Rotor blade setSW104 · SW1031,2,3,4,5—Silent Power Blades: hand-laminated carbon, about 142–150 g each and matched within 0.6 g, so they are sold as a balanced set of three: SW104 in the 2019 catalogue, no. 1 in the 2023 list; the manual’s packing list counts three of the single blade SW103. Since March 2024 the blades carry a simpler logo; design, method and materials are unchanged.
Fastening kitSW106 · 000181,3,2—Blade screw kit: six M6 × 22 stainless screws, six plastic washers against electrolytic corrosion and six self-locking nuts (no. 00018 in the 2023 list). SW107 is the hub with this kit. Tighten to 7–8 N·m.
Rotor hubSW105 · 742,1,3,6—Powder-coated aluminium hub for the three blades (no. 74 in the 2023 list); SW107 comes with the blade screw kit. Hub and centre nut are marked, and the marks must line up.
Rotor centre nutSW102 · 2381,3,2,6—M16 stainless centre nut that holds the hub on the shaft (no. 238 in the 2023 list): 30 N·m, arrow towards the generator, mark lined up with the hub. Replace it if the rotor runs out of balance.
Nose coneSW101 · 772,1,3,7—Snaps onto the hub with three plugs; pull it straight off to remove (no. 77 in the 2023 list).
Generator bearingSW203 · 701,3,8—Rotor bearing kit: two 6203 2RZ ball bearings, snap ring and 4 mm distance gasket (no. 70 in the 2023 list; stainless 6203 2RS bearings on request). e-Marine’s version of the kit adds the front O-ring, which it says to renew whenever the generator has been opened.
O-ringSW202 · 073481,3,9—Silicone O-ring between front cover and body (no. 07348 in the 2023 list). The front cover is held by three M5 × 50 stainless screws (SW201); a missing or pinched O-ring lets water in.
Generator statorSW204 · 204 · 205 · 2061,3,10,11—Complete generator front: front cover with the stator pressed in, O-ring and rotor bearing kit. The 2019 catalogue lists it as SW204 (e-Marine: stator assembly SW204); the 2023 list by voltage as generator head 204 (12 V, v2018), 205 (24 V, v2015) and 206 (48 V, v2015). Cover and stator are pressed together at the factory.
Generator stator239 · 240 · 2413,11—Stator (windings) alone: 239 for 12 V (v2018), 240 for 24 V and 241 for 48 V (both v2015). Silentwind advises owners not to press a stator into the cover themselves.
Generator rotor (magnets)SW301 · 751,3,11—Generator rotor complete: shaft with twelve NdFeB magnets and the 7 mm washer (no. 75 in the 2023 list; washer alone no. 87). Since 2020 the standard rotor has a metal tape over the magnets. The magnets are strong enough to cause injury.
Generator brush assemblySW406 · 1912,3,1,2—Set of three brushes with springs in the slip-ring unit (no. 19 in the 2023 list; SW406 at e-Marine). Brushes that lose contact stop the charging: clean or replace them together with the springs.
Slip ring unitSW601 · 2311,3,11—Slip-ring unit with its cable (UL1015, 12 AWG) down the yaw shaft; the 2023 list sells it as no. 231 together with the yaw-shaft snap ring. It unscrews with an 8 mm hex key while the yaw shaft is turned; each ring should measure close to 0 Ω, and 2–3 Ω is already too much.
Main circuit boardSW402 · SW_COMPO451,13,14,3—Small interface board where the stator wires meet the slip ring (no. 45 in the 2023 list). Revision 1 generators (from November 2024) use a commutator bar, SW_COMPO46, and a stator temperature sensor instead; Silentwind converts older generators only at the owner’s cost.
Generator bodySW501 · 172,1,3—Powder-coated aluminium body, white RAL 9010, supplied with the yaw bearings and snap ring (no. 17 in the 2023 list).
Yaw bearingsSW502 · 331,3,9—Two 6007 2RZ C2 ball bearings and snap ring for the yaw (no. 33 in the 2023 list; stainless 6007 2RS kit no. 236 on request). Corroded yaw bearings stop the generator turning into the wind.
Yaw shaft kitSW602 · 2331,3,15—Yaw shaft kit: yaw body, yaw clamp (no. 234), four M6 × 35 stainless screws with self-locking nuts and the rubber damping pad (no. 233 in the 2023 list); slip ring and bearings are separate.
Mounting pad2323,1,16,2—Rubber damping pad between the yaw clamp and the mast top, which keeps vibration out of the mast; always fit it.
Charge controllerSW701 · 214 · 215 · 2162,1,3,17,18,19—MPPT Hybrid Boost charge controller: SW701 in the manual; in the 2023 list 214 (12 V), 215 (24 V) and 216 (48 V). It works with every Silentwind generator of the same voltage back to 2010 and comes with the external temperature-sensor cable and a Bluetooth antenna. 12 V and 24 V units are the same hardware with different firmware.
Cable258 · 25920,21—Brake and sensor cable upgrade for MPPT controllers from 2019 (controller Rev. 1 or later): 258 is the internal 4-pin connector cable, 259 the external cable, so a remote brake switch and the battery temperature sensor can both be connected.
Mounting tube22022,23—Section mast, screw-joint model: three 1 m tubes of polished marine-grade stainless, 48.5 mm outside and 43.3 mm inside diameter, 2.6 mm wall, 3 m when assembled. Shorten only the top or bottom section, never the middle one; it needs a mast mounting kit with stays, with the clamps on the top section.
Mast mounting kit—24,22—Mast mounting kit for 48 mm masts (no. 38 in the section-mast manual): swivelling stainless mast foot with rubber damping and cable entry, two mast clamps with stay ends and two lower stay ends; stay tubes (19 mm inside) and screws are not included. Fit the clamps at least 55 cm below the mast top so the blades clear the stays.

Numbers checked against the sources below on 23 October 2026. Always confirm against your serial number and exact type before ordering.

Service intervals

TaskInterval
First serviceAfter about a week: check the central rotor nut and the six blade screws for tightness2
Rotor bladesEvery 3 months (later possibly less often): look for broken edges, surface damage or cracks and stop the generator at once if you find any. The maker’s “Read me first” sheet adds a monthly clean and check and a tip-to-tip measurement every 6 months (about 990 mm, no more than 5 mm difference)2,6
Bolted connectionsEvery 12 months: hub screws, central shaft nut and mast fixings2
Generator bearingEvery 12 months: shaft and yaw bearings (sealed, lubricated for life) must turn freely and quietly; replace noisy or damaged ones. On average they last 4 to 5 years2,6
Slip rings & carbon brushesAbout every 5 years, or sooner if output drops: clean the slip-ring contacts (clean cloth, then isopropyl alcohol, as a last resort 600-grit paper) and check brushes and springs6,11,2
Corrosion protectionEvery 12 months (the “Read me first” sheet says look monthly): touch up chips in the powder coat with RAL 9010 paint before sea water creeps under it; Duralac or Tefgel on the four yaw-clamp bolts against galvanic corrosion2,6
Mast and mountingEvery 12 months: mast, stays and clamps stable, no loose screws2,24
Electrical connectionsEvery 12 months: all connections tight and free of corrosion (remove it and treat with contact spray); clean the battery terminals and grease them with Vaseline2

From the Silentwind Pro user manual (August 2024), the maker’s “Read me first” sheet and its low-power troubleshooting guide. Before any check, brake the generator, tie the blades and disconnect the battery from the controller in the order the manual gives. The charge controller has no user-serviceable parts.

Specifications

TypeThree-phase permanent-magnet AC generator with no charge electronics in the head; the AC runs through a slip ring with three brushes in the yaw to an external charge controller that rectifies, charges and brakes (electronic brake and storm brake)2,11,3,25
ModelsSilentwind Pro 12 V, 24 V and 48 V, each with the MPPT Hybrid Boost charge controller of the same voltage. Revision 1 (announced November 2024) adds a temperature sensor in the stator and a commutator bar in place of the small circuit board; the label inside the yaw shaft gives model, serial number, revision and voltage2,14,25
Years builtFirst generation 2010–2012 (12 and 24 V only, serial numbers 20101001–20111558); Silentwind 400+ second generation 2012–2015 and third generation 2015–2019; Silentwind Pro (fourth generation) since 2019, serial numbers from 20180001 (12 V), 20182001 (24 V) and 20183001 (48 V). The first four digits of the serial number are the production year17
OutputRated 420 W (12 V), 450 W (24 V) or 500 W (48 V) at 14.5 m/s; the Silentwind 400+ data sheet of 2018 gives the same figures2,26
Wind speedsStarts turning at 2 m/s, charges from 2.2 m/s (4.3 kn), rated output at 14.5 m/s; wind-tunnel tested to 122 km/h without failure2,25
Rotor1.15 m diameter, three blades, 550–1700 rpm, turning clockwise seen from the front; tip-to-tip distance about 990 mm (±5 mm)2
MaterialBlades: hand-laminated carbon fibre, UV-resistant, about 150 g each, balanced as a set (within 0.6 g of each other). Body: powder-coated aluminium, white RAL 90102,5
WeightGenerator 6.8 kg; MPPT charge controller 2.3 kg; shipping box 780 × 400 × 210 mm, 10 kg2,18
Voltage12, 24 or 48 V DC: battery bank, generator and charge controller must all have the same nominal voltage. The current Hybrid Boost controllers suit every Silentwind generation of their voltage2,18,17
Charge controllerMPPT Hybrid Boost (Rev. 2): wind input up to 600 W (40, 30 or 15 A at 12, 24 or 48 V), solar input up to 300 W (20, 10 or 5 A), total charge current 60 A, two 10 A load outputs (not on 48 V), LCD, electronic brake and storm brake, battery temperature sensor; for lead-acid, gel, AGM and lithium (LiFePO4) batteries18,25
Controller default settingsFactory defaults (gel/AGM) at 12/24/48 V: end of charge 14.4/28.8/57.6 V, overvoltage 16/32/64 V, low-wind boost 3/4/10 V, storm brake 32/16/9 A, undervoltage switch-off 10.8/21.6/43.2 V, recovery 12/24/48 V. At end of charge the rotor brakes for about 10 minutes; charging resumes 1.3/2.6/5.2 V below the end-of-charge voltage18,27,28
Data connectionsBluetooth to the free Silentwind app (iOS and Android), where all parameters can be read and set; the controller shows up as “Win-Power”. Ethernet and Modbus (RS485) on request18,29,25
MountingOn its own mast, 48–50 mm outside diameter, preferably marine-grade stainless (aluminium only from certified mast makers), wall at least 1.5 mm for up to 3 m, held by rigid stays; blades about 3 m above deck, an upper mast bracket about 20 cm below the lowest blade tip, rubber between every clamp, the mast foot and the deck. Not in line with a backstay, and not on a frame that also carries solar panels or a bimini2
Tightening torquesBlade screws 7–8 N·m (more damages the blades); central M16 rotor nut 30 N·m, arrow towards the generator, marks on nut and hub lined up; the four yaw-clamp screws evenly, in small steps2,6
Power cable sizeThree AC wires of the same size. 12 V, generator to controller: 6 mm² up to 9 m, 10 mm² up to 19 m, 16 mm² up to 29 m; controller to battery: 16 mm² up to 9 m, 25 mm² (AWG 4) up to 19 m. 24 V: 2.5 mm² up to 9 m, 4 mm² up to 19 m, 6 mm² up to 29 m; to the battery 16 mm² up to 9 m. 48 V: 2.5 mm² up to 29 m; to the battery 4 mm² up to 69 m. Tinned copper on boats2,18
Breaker / fuseFuses in the positive leads close to the battery: 12 V 50 A (wind) + 25 A (solar); 24 V 30 A + 15 A; 48 V 20 A + 10 A2,18
Operating temperatureCharge controller −20 to +40 °C: indoors, dry and ventilated, out of the sun, 30 cm clear all round, mounted upright on a wall because the case is the heat sink18,25
Waterproof ratingCharge controller IP5218
Warranty3 years on generator and charge controller (proof of purchase and serial number required); spare parts 90 days for end users2,3

Good to know

  • Order matters: connect the charge controller to the battery first, then the solar panels, then the generator, and undo it in reverse. A controller that gets wind power with no battery behind it quickly overheats, and reversed battery polarity destroys it outright. To work on the system, brake it at the controller (hold the button 5 s), tie the blades or tape the AC wires together; before a storm, brake and lash one blade to the mast.2,30,18
  • Most vibration comes from the mast (Silentwind puts it at 90 %): rubber at every joint, stays and an upper bracket just below the blades. Then check the rotor: blade tips equally spaced (about 990 mm, ±5 mm), the marks on hub and M16 nut lined up and the hub running true; a nut that throws the rotor out of balance should be replaced. Recheck the nut and blade screws after the first week.2,6
  • After opening the generator (bearings, slip ring, windings), make sure the silicone O-ring sits properly and the three front screws are fully home: water that gets in corrodes the yaw bearings until the generator no longer follows the wind. When mounting, keep the slip-ring wires out from between the yaw clamp and the mast; chafed insulation leaks current to the mast, and a short between the phases brakes the rotor, sometimes only months later.9,31
  • Low output despite wind: rule out the brake and wrong settings, then measure the resistance between the three AC wires on the lowest range (it must resolve 0.001 Ω), first at the controller, then at the generator. Generators of the Hybrid Boost MPPT era read about 0.3 Ω (12 V), 0.5 Ω (24 V) and 1.2 Ω (48 V). Right at the generator but wrong at the controller points to the extension cable or crimps; right at the windings but wrong at the generator wires means the slip ring needs cleaning. With batteries under 150 Ah the end-of-charge voltage comes early and the rotor brakes for 10 minutes; a load on the output helps.11,2
  • Buying used: the serial number (inside the yaw shaft, on the USB-stick box and the carton) starts with the production year. Generators up to 2015 may come with a Hybrid 600 or Hybrid 1000 controller, which does not work with later generators; a first- or second-generation generator on a current Hybrid Boost controller needs its low-wind boost set to 11 V (12 V), 4 V (24 V) or 10 V (48 V). Replacement blades come only as a balanced set of three.17,32,3
  • On MPPT controllers made since 2019 (controller Rev. 1 or later) the small two-pin socket carries only the battery temperature sensor; a remote brake switch needs the brake and sensor cable upgrade (258 inside, 259 outside). Use a plain on/off switch: putting power on the brake wires destroys the controller. Mount the sensor on or next to the battery (without it the controller assumes 25 °C), and pair Bluetooth only inside the Silentwind app, never from the phone’s Bluetooth list.21,20,29

Videos & how-tos

Links to YouTube, nothing embedded. The maker’s own channel comes first; the rest are channels we found clear and correct for this model.

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Sources

  1. web.archive.org/web/20190820144022/https://www.silentwindgenerator.com/wp-content/uploads…
  2. silentwind.com/storage/files/1780301808/1silentwind-pro-user-manual-en.pdf
  3. silentwind.com/storage/files/4spare-parts-list-en.pdf
  4. silentwind.com/storage/files/8silentwind-blades-new-revision.pdf
  5. web.archive.org/web/20190722094209/https://www.silentwindgenerator.com/en/how-to-correctl…
  6. silentwind.com/storage/files/1780301878/0warning-document.pdf
  7. emarineinc.com/products/silentwind-nose-cone
  8. emarineinc.com/products/axis-bearing-kit
  9. silentwind.com/storage/files/5water-infiltration-v2.pdf
  10. emarineinc.com/products/silentwind-stator-assembly
  11. silentwind.com/storage/files/9troubleshooting-low-power.pdf
  12. emarineinc.com/products/silentwind-brush-assembly
  13. emarineinc.com/products/silentwind-interface-pcb
  14. silentwind.com/storage/files/10product-change.pdf
  15. emarineinc.com/products/silentwind-yaw-assembly
  16. emarineinc.com/products/silent-wind-yaw-damping-rubber-pad
  17. silentwind.com/storage/files/6compatibility-matrix.pdf
  18. silentwind.com/storage/files/2mppt-user-manual-en.pdf
  19. silentwind.com/storage/files/11factory-default-reset.pdf
  20. silentwind.com/storage/files/7external-brake-and-sensor-cables-upgrade.pdf
  21. silentwind.com/storage/files/2external-cable-information.pdf
  22. silentwind.com/storage/files/3section-mast-user-manual-en.pdf
  23. web.archive.org/web/20190722103916/https://www.silentwindgenerator.com/en/product/segment…
  24. silentwind.com/storage/files/4mast-mounting-kit.pdf
  25. silentwind.com/produc
  26. web.archive.org/web/20190820144022/https://www.silentwindgenerator.com/wp-content/uploads…
  27. silentwind.com/storage/files/8standard-controller-settings.pdf
  28. silentwind.com/storage/files/4charging-cycle-explained-v2.pdf
  29. silentwind.com/storage/files/9connection-issues.pdf
  30. silentwind.com/storage/files/7how-to-safely-disconnect.pdf
  31. silentwind.com/storage/files/6assembly-problems-v2.pdf
  32. silentwind.com/storage/files/3label-information.pdf

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