Servicing the 6kW Proven on Scoraig

I have just done a service on our local Proven 6kW (aka Proven 11, aka Kingspan Wind KW6) at the Council’s School here on Scoraig.  First time it has been taken down since 2006.  Installed in 2003 by Sangsters.

Nothing much goes wrong with this particular turbine.  The covers blew off in 2005, and this happened again last November (2011) and I finally got the go ahead to put them back on so I took it down yesterday, and sorted out a few minor issues.  Greased the bearings, and replaced some plastic bits and bobs.  Renewed the cable-ties and added a few to the covers.  Cranked it back up on its 15 metre free standing pole today (took about 45 minutes with a 3200kg Tirfor).

Click on a photo to see it full size, with extra comments in some cases.


This entry was posted in my own projects, products/technical, Scoraig, UK small wind scene. Bookmark the permalink.

38 Responses to Servicing the 6kW Proven on Scoraig

  1. rob-wales says:

    where can proven 6 kw service/replacement bit/parts/gaurds etc. be bought from please?

  2. aidan says:

    Hi hugh
    ive a 6kw proven up just over 5 years serviced it there using teleported
    am hoping to lower it next service myself would a 3/4 inch break bar loosin the bolts
    at the bottom ,are they 45/46 mm i think has hire out the pulley for lowering it
    what thickness of wire rope did you use was it 30 metres in length .i found your article
    very good and photos are a big help hope to hear from you ta

    • admin says:

      hi Aidan I have used a 3.2 ton tirfor pulling directly to lower the turbine in the past but it’s a bit close to the limit and I would recommend using a pulley with it and a 40 metre rope. also I would not buy an actual tirfor as they are so expensive. Go to AP lifting for the hoist and the pulley and rope for a good deal. I admit I forget the size of spanner, but it is the standard size for M30 thread.

  3. Roger says:

    Hi, Hugh,
    I’ve read your the uy to talk to about wind turbine and wondering if you could help me? about 4 years back i got a proven 6kw windturbine put up and have been dissappointed with it it generates about 3500 kwh a year which was half what i expected . Heres my question the turbine was listed with proven as a under generating machine they sent out a team to look at it they took measurements took it down but did nothing they did tell me the distance between the magnets and the coil was 10mm one side and 6mm the other which seemed odd to me (what are the distances ment to be?) . im inland wind speed 5 m/s it goes to a sunnyboy sma 6000a inverter ( which has has the chip added to make it 7-8 point multitracking instead of 3 which came with it) . i even had a new tranformer put on the electric pole as the old one was putting out too high a voltage. . The retifier box is fancy records revs and volts and amps and to me i always seem on the cusp of making usable power is they anything i could do to tweek it ? im not affraid to take it down even engineer bits . But my main wondering was what are the tolerances between magnets and coils
    thanks roger

    • admin says:

      hi Roger,

      My first reaction is to wonder if there is actually enough wind at your site and whether you are measuring this? I tend to see a lot of provens under trees and in completely unsuitable locations on towers that are too short.

      10 mm seems a pretty big gap between magnets and stator it is true. It may be that the turbine is unable to reach a usable voltage even though the windspeed is enough to produce some output. Can you pass on some actual data for rpm and power? AT 3 m/s windspeed, a 5.6 metre turbine with tip speed ratio 6 should get to 60 x 3 x 6 / 5.6 / pi = about 60 rpm. Does it reach a usable voltage at 60 rpm?

      You might be able to increase the rpm at cut-in by using a finer pitch setting on the blades. Take care however as this may alter the governing by delaying stall and thence overload the turbine in stronger winds.

      some ideas for you


      • Roger says:

        Hello Hugh,
        Firstly thank you for replying , proven sadly changed hands just as the proven team were trying to sort it out but they installed a 6 kw data logger box I have just this minute taken out the sd card in it I’m not sure if I can read the data on it without proven software tho ( if not do you have or know where I can get it?) I get no usable power at 60 rpm it doesn’t generate til at least 150 rpm them reaches max output at 177 rpm . I forgot to mention the turbine is on a 15 metre mast the cu type no guide wires .
        Voltage wise it starts feeding into the grid at 257 volts and is at full output at 275 ish volts . These maybe rough as to be honest I have stopped monitoring it but will look on the sd as there should be a few years of data thanks roger

        • admin says:

          Hi roger,

          I’d say the simplest way to tap into power at lower windspeeds would be to use a second inverter that works at a wider range of voltages. For example have you looked at the aurora? I am not a grid tie expert but I believe it offers a wider operating range and could maybe replace or supplement the windy boy? then you could start at a lower voltage.


  4. Roger says:

    Hi Hugh,
    Just had a look at that sd card and it has data on from the last two year each month is about 4meg of data I could send you a months worth if I had your email but will provide a little here . The turbine itself is I think in not a bad place there is a wood about 120 yards to the west of it but a clear way from the south west for 300 yards . On the 15 metre mast too average wind speed from wind charts were about 5 m/ s . , anyhow cast your eye over this data please and tell me what you think I shall give info for each kw and start up there are a few numbers I don’t get but will include as they may mean something. V 245. Amps 0.2. Kw0.1. D 1.7 ( don’t know what d means that’s how it is written in notepad) R 129.7 m 137.7 don’t know what m means r is rpm
    At 1 kw. V265.5 A 3.8 D1.7 R 151. M180
    At 2kw. V279 A 7.2 D 1.7 R 166 M194
    At 3kw V 291 A. 10.5 D 1.8 R 180 M 207
    At 4 kw V 303 A13.1 D 1.8 R 193 M 247
    At 5 kw V 340 A14.8 D1.5. R222. M293
    At 5.9kw V 347. A17.2. D1.0. R233. M278
    These are the figures Taken from the datalogging machine installed along with the wind turbine installation later installed was a heap dump in the form of two 3kw heaters for fear that the wind turbine my overproduce which seemed weird as it was under producing ( well I thought it was)

  5. Roger says:

    Hi Hugh,

    I forgot to add that this turbine is a grid connect whether this makes a difference I don’t know . It’s just frustrating to see it spinning and producing very little the fact is looking through the data it spins at 100- 125 rpm a lot of the time and the voltage is around the 240 mark but its just before producing
    Any help or input is greatly appreciated thanks roger

    • admin says:


      Like I wrote above it could be as simple as getting another inverter that can load it at lower voltages. Just because it underproduces in low winds does not mean it will not also overproduce in high winds. Again a second inverter might help (or not if it just pushes the grid voltage out of limits and crashed the inverters).

      Low winds do not produce a great deal of energy but it’s obviously frustrating you not to get it. Maybe the turbine does not start to produce a high enough voltage until 6 m/sin which case you are losing out on a fair bit of energy.

      Hugh Piggott

      • Andy Reynolds says:

        HI. I have a had a long battle with Proven about the poor output of their generators, and when my machine was returned for warranty repairs, they lost it for quite some time and when it was finally returned it was worse than before with 5mm air gap between the magnets and rotor. In early conversations with Richard, Ken and others it was established that the gap between rotor and stator should be less about 2mm. This was for the (laughingly called) 2.5Kw machine, that is in fact a 1.5 if lucky. What ever R Caldow says through my experience should be tempered with a BS filter.

  6. Roger says:

    Hi Hugh,
    Due to the very high winds today my turbine has stopped working , reading the sd card it stopped after it was producing 500 v and doing 370 rpm looking at the data it’s stopped producing then came back on and off . So I’m forced to take it down could I ask you what winch to get and how much wire rope I would need . Seen a t35 tirfor winch with 10 metres of wire rope this lifts 3 t and pulls 5 t. Would this do ? Or do you know anyone that hires them in the yorkshire area ? Many thanks roger

  7. Roger says:

    Hi Hugh,
    Looked up ap lifting they have 3200 rope hoist at a good price , you talk about using a pulley I take it the pulley is d linked to canter lever and the wire rope is connected to the anchor point then runs round the pulley back to the winch which is connected to the same anchor point as the wire rope is this how it’s done ? And is 40 metres of rope enough ? Also would I be able to undo the base bolts without a torque multiplier , what
    Are the torque setting for the bolts I heard 1600 newtons that right thanks agin roger

    • admin says:

      Foundation Bolt Torques Nm for different sizes and grades of steel. (8.8 10.9)
      Size 8.8 10.9
      M20 320 460
      M24 550 800
      M30 1100 1600
      M36 1900 2750

      I think they are M30. 1100 Newton metres
      Use a piece of pipe over the socket wrench bar. Yes you got the idea for the lift. Make sure the shackles are strong enough.

      LSBS616 SNATCHBLOCK WITH SWIVEL SHACKLE £ 78.00 is good for the 40 metre tirfor rope.
      A 20 metre rope might work depending on the foundation layout. I have used a tirfor without pulley several times (as advised by proven) but it’s rather dodgy, and the pulley is a better plan for sure.

      • Hola Hugh, Myname is Toro Martinez, and Im in Argentina, where we do have the Patagonia, which you might heard about its winds, I was very realted to Proven in the past, and I do have a question that it might not be easy to answer……….
        Do you think that Kingspan, maintain the quality and reliablity that Proven used to have ????
        thank you, my best regards

        • admin says:

          hi toro,

          to be honest I don’t have much experience with kingspan. The Proven is a sturdy machine and this is a good thing for high wind sites. The company did not have a reputation for good customer care and I doubt if that has changed. But the design has a long history and so the little problems should all have been solved by now.

  8. Aidan says:

    Hi Hugh how’s things I’m wondering if it would be possible to make up a hydraulic ram system to lower my turbine for serviceing I see some clips on YouTube of turbines with rams fitted to them.So far my turbine has clocked up near 80000 units in approximately 5 and half year luckily with just yaw rollers and greasing every service .Hopefully next year I’ll try and change the plastic spacers and washers on the blade springs do you know if king span can supply them without having to buy springs .

  9. admin says:


    I am not sure about the hydraulic ram. A tirfor-type winch is less costly if you only have one turbine. You would need a gin pole or A-frame.

    Washers you can get from RS at search for product code 280-543.

    I got the plastic pipe off ebay. I can sell you some as I got loads just let me know your needs.

    I imagine you could make the spacers out of any thing if you don’t want to buy them. I’d check first of all with kingspan to see if they do an affordable refurb kit. I don’t deal with them as I am not MCS reg. Even the above turbine has been taken over by MCS certificated guys.


    • Aidan says:

      Thanks Hugh I’ll get on to kinspan and see if they do a refurb kit if not I’ll be in contact OK Ta

    • Aidan says:

      Hi Hugh got some nylon washers do you know of hand the size of the bolt that the washers and the pipe bushes go on to on the springs as for that pipe I would take some

      • admin says:

        Hi Aidan,

        The pipe is 10mm internal, 12mm Overall diameter. I can sell it for £2 per metre. Let me know how much you want. Best to specify multiple short lengths if possible, so I can post it cheaply to you.

        • Aidan says:

          Hi Hugh
          I’ll take 1 metre of that pipe in roughly the size that you put on the turbine you serviced does it replace the worn blue pipe in your photo then just put new washers and spacers if needed on the spring ends
          I measured the bolts at the base the ones that taken out when lowering does 45 mm sound right to you

  10. Jon Leckey says:

    Hi Hugh
    I have a Proven 6kW on 15m mast. The yawl bearing has gone so that theres a scary amount of vibration and unfortunately the brake rope has just gone a few days before the service was planned. The advice from the service people so far is to wait for no wind, but that could be weeks by the look of the forecast. Have you any advice on emergency stopping methods such as trying to steer the turbine out of wind? Thanks,
    Jon L

    • admin says:

      Hi Jon,

      I never had much luck with that disk brake. The best way to stop a Proven is like other windmills – short circuit it. Not a good idea to keep a short circuit on in a high wind, as the alternator may catch fire after a few hours if it doesn’t stop. But if the wind is just normal it will stop at once.

      Simplest way to short it is to isolate the turbine first so you can work on the wiring. Be aware there may still be dangerous voltages present from the capacitors in the inverter (I am assuming this is grid tied). Then short all of the 3 AC wires together with a robust pair of links. Then re-connect the windmill and it should pretty much stop. It may turn very slowly but nothing to worry about.

      I hope this allows you to take it down safely. If it is vibrating a lot then this is likely due to something coming off it – for example maybe some springs have flown away? A loose yaw bearing will not make the machine shake.

      Best of luck!

  11. Jon Leckey says:

    Hi Hugh,
    Thanks for that. The service people also mentioned the shorting method, but good to hear the details from your experience. (The other interesting suggestion was to lassoo one of the blades but Id suspect John Wayne would find that tough at 15m)! Ill keep you posted, will wait for the wind to pipe down a bit.

  12. I have had one of these machines grid connected since 2008 at a coastal site in Cornwall. The power collected initially was in excess of the top end of the manufacturer’s specification, with several periods of hours of 6kW being generated. But it has fallen off over the past couple of years, and I have never seen it delivering its peak power over these two years. Last year when there were incessant winter gales, it never rose much beyond 4kWp. It is serviced annually by the original installers. They say that they have several customers with this problem but seem to be at a loss as to what is causing it. They have several theories, such as weakening magnets or weakening coils. (I am not sure what the latter even means. Shorted turns, higher resistance wire?)

    I have fitted a power frequency meter from eBay to the turbine output. I have tried setting the voltage higher (and the current lower) so that the turbine spins faster, and the AC frequency rises to 23Hz. I have tried setting the voltage lower, but despite fierce winds the frequency never rose above 19.5Hz and the total peak power never exceeded 4kW.

    I am guessing that the springs could have weakened due to excessive use during the first four years, causing the turbine to have modified itself from 6kWp to 4kWp. But ordering the installers to change them could prove expensive if this is not the correct answer.

    I assume that the springs comprise a linear control system, ie the faster it goes the more feathering is applied. A non linear system would be more effective, ie the blades extract the maximum amount of energy from the wind until a set speed is reached, at which time governing sets in.

    I would be interested if anyone else who comes across this page has had a similar experience with this machine.

    • admin says:

      hi John,

      A few people have commented on this drop in output so I thought it worthwhile to ask the manufacturer, and sent an email to Richard Caldow, Kingspan Wind General Manager, who has been with Proven from the outset. Here is his reply which he agreed to me copying here:

      “Looking through the blog I think the tail off in power might well be due to the spring inserts wearing over a period of time. The plastic insert sets the pre load of the spring and if worn there would be less preload to overcome before the blades start to cone and reduce the swept area. We offer a spring repair kit which replaces all the wearing parts. I would recommend this be done every second service (four years) or every service in high/extreme wind sites.

      “There has been some speculation on the magnets loosing flux but we have recently had some machines in for overhaul and took the opportunity to test them and found little reduction. Happy for you to post my comments and if you ever require any clarification or support please do not hesitate to contact me.”

      The springs are not linear in the sense of “the faster it goes the more feathering is applied”. There is a preload built in which must be overcome before the blade hinges begin to unwind, twisting the pitch toward stall. If the cause of the degraded performance is the springs reducing their “preload” then they will start to extend sooner, and the machine will begin to stall at lower rpm, and this will give you less peak power. A simple fix that comes to mind is to alter the inverter settings so as to harvest power at lower voltage/rpm but this would not work in practice, because the increased torque at low rpm would push the blades into stall even harder. Stalling by passive pitch regulation is an inherently unstable process and it has always been tricky to get the desired output and maintain it.

      I would recommend a direct approach to Kingspan, starting with their spring repair kit, and if this does not produce results then follow up with a request for more effective remedies. I hope this helps 🙂


      • Over a year later, the installer have now installed replacement second hand (but newer) blades, and the machine is again giving 6kW. They had tried the solution suggested above, but it did not work. However they found that one of the bars holding it down into the concrete foundations had rusted through, and at great expense (£1,611.53) I had the plate and foundations drilled to insert 5 more bars fixed with Hilti RE500 to hold it down (now a total of 11). However there are still some vibrations, as seen on
        They can’t be felt, but the water is obviously a very sensitive indicator.

  13. GERALD RIGBY says:


    URGENT main bearing gone how do I get the main shaft out is the disc brake welded in place or locktited on I cannot seem to move the disc or stator all 8 bearing bolts are undone and they move but not the disc or stator


  14. GERALD RIGBY says:

    Forgot to say

    PROVEN 6KW turbine


  15. bob stratford says:

    I have read up about a lot of wind turbines. It appears there is not many that you can say are good. Most verticals are very over rated. Some don’t even generate any power. A proven 6 is for sale not far from me. It appears the pole broke at the bottom and it as been very badly damaged. I was surprised how heath robinson the design is. I have been off grid for many years with various wind turbines which were not that good. In the end I decided to build my own 24 volt. Every part I designed and built. I dont believe there is another turbine to compete with its performance. At 3.3m diameter it starts to produce power at 5 mph and peaked at over 5 kw in a 44 mph wind when it did not furl quick enough. I have just checked it and it is still in the condition as the day I first started it up 12 months ago.

  16. Ken Keane says:

    URGENT…. I have a 2.5 Proven wind turbine that has just broken a spring. The new brake pads that were put in by an engineer won’t hold it. My turbine has only two springs on each blade and I notice on the newer models they seem to have three springs. Will it be ok to replace my two spring units with three new three spring units I imagine it should be stronger job for the ever increasing storms we are experiencing in the west of Ireland. Next questions, is Kingspan the quickest to deliver or are there other suppliers. I have to hire out a Tirfor to take the turbine down so I would like to have the springs in stock and hope for a calm day. I would appreciate any help. K.

  17. John says:

    I looking for the possibility of buying a second hand King span or Proven 6KW
    Wind Turbine with a 15metre Hydraulic tower in very good condition

  18. Dave in Alaska says:

    I’ve had the Proven 6k for a number of years with reliable success. Nice low speed start up with 7.1 kW output repeatedly. I installed grease whips down to a platform height where I can reach it. The unit is mounted about 120′ high which is about 30′ above surrounding trees and such. This was unit has provided steady power source since installed. Generator run time has been virtually eliminated.

    • Jerry Brucaya says:

      I too have a 6kw on a 120′ lattice tower in Wisconsin. I designed and had fabricated a circular platform attached to the top or the tower just large enough to not interfere with any slapjack from the blades. I also put grease whips on and a small cutout for the mast bearing so less dismantling of the covers. I got over 7kw when new, but it barely does 6kw now. Last time I was up I saw springs needed replacement bushings and rod inserts. Have e-mailed and called proven, but no response to either. Know where or how we can get parts when needed?

  19. The barrel covers blew off in a gale a month ago. I made some new ones using the old ones as templates within a few days, but the local company can’t fit them for another month, ie the machine will have been working without the barrel covers for two months. It is the summer, and a dry one at that. When the wind blows, the slip rings will be sheltered by the alternator.

    I have recently added a Sofar ME3000SP 9.6kWhr battery storage system, which works really well with the Proven turbine. As the wind gusts it stores the excess energy, and when it slackens, it uses it at the house as opposed to buying it from the grid. A very rough estimate from results so far suggests that the addition earns about 10% return on its cost … per quarter! (Probably less in the two winter quarters with less PV input, but there will be more wind. I put it in in April.)

    Does anyone here have any view as to whether I should be concerned about the delay in replacing the covers? Although the company is based locally, it has customers over the entire UK.

    Also, is the use of cable ties to keep the covers on the best that can be done? Has anyone applied a better form of fixing to their turbine?

    • hugh says:

      I have turn Proven turbines without covers for long periods and the sliprings did not seem to suffer. They are very heavy duty sliprings. I guess you might get arcing in wet weather at higher voltages. I have only used them up to 140VDC (around 100Vac rms).

Leave a Reply

Your email address will not be published. Required fields are marked *