JohnD Posted February 10, 2020 Author Share Posted February 10, 2020 Thank you, Peter - clearly I failed the tutorial! Bu The big windmills near me feather their blades. I believe that the objective is to maintain a constant speed in the face of varying wind speed. In a high wind, they adjust feather to produce zero lift. ??? JOhn Link to comment Share on other sites More sharing options...
RogerH Posted February 10, 2020 Share Posted February 10, 2020 Hi RR, you certainly can stop or slow an electric motor by removing the power and shorting the input V to earth. When a motor is coasting after removing the power they turn into Generators. Ground the Input V wire (which is not the Output V wire) and the electric load stops it dead. As per the TR6 14W wiper mtor. However if you have a bl**dy big fan turning a generator the above would not work. Turning the variable pitch blades to fine would help to slow it. But a mechanocal brake may work completely. Roger Link to comment Share on other sites More sharing options...
JohnD Posted February 10, 2020 Author Share Posted February 10, 2020 I knew that! My electric fan has an illuminated switch, which is lit up at night (and presumably in the day) when at speed, even if the fan is off! J. Link to comment Share on other sites More sharing options...
PeterC Posted February 10, 2020 Share Posted February 10, 2020 4 hours ago, richy_rich said: I thought you braked them by shorting out the generator so it's working against itself, or did I just make that up in my head? The generator load is adjusted continuosly to keep rotation speed constant. Bllade tip velocity is around 140 mph for most w'ts, and in most blades are not featherable. However above 60 mph no more load can be applied and the brake comes into action. Its a disc brake on w/ts wiih a gearbox, whose output shaft turns ca 80-fold faster than the hub. On direct drive w/ts the main shaft turns at hub and generator speed, and I dont know what sort of brake is used. The torque that has to be braked is enormous, a 3MW w/t in 40-60 mph wind puts out ca 4000 hp. similar to an railway loco, Link to comment Share on other sites More sharing options...
PeterC Posted February 10, 2020 Share Posted February 10, 2020 3 hours ago, JohnD said: Thank you, Peter - clearly I failed the tutorial! Bu The big windmills near me feather their blades. I believe that the objective is to maintain a constant speed in the face of varying wind speed. In a high wind, they adjust feather to produce zero lift. ??? JOhn Only modern direct drive, two speed w/ts can do that. Thier nacelles are short rounded and stubby. They park with one blade aligned with the tower but I think thay still need braking. Siemens make d/d w'ts. Peter Link to comment Share on other sites More sharing options...
PeterC Posted February 10, 2020 Share Posted February 10, 2020 Re w/t blade feathering: https://www.energy.gov/eere/articles/wind-turbines-extreme-weather-solutions-hurricane-resiliency The technology has moved on since I was fighting them Peter Link to comment Share on other sites More sharing options...
Chris W Posted February 11, 2020 Share Posted February 11, 2020 I don't know if my fence panels were damaged by the storm. I'll let you know when I find them! Link to comment Share on other sites More sharing options...
rogerguzzi Posted February 11, 2020 Share Posted February 11, 2020 Hello All What with all this wind and a bit of sun no generator power needed for the last 4 days and new batteries fully charged and I have just turned the immersion heater on to use some of the excess power! This is the size we have now and rated at 930 amp/hrs a C5 1081 amp/hours at C10 1114 amp/hrs at C20 usual car battery standard 1423 amp/hrs at C100 C stands for how much power can be removed at these number of hours (I case anyone does not know) Roger DIN Standard 2 Volt Cells All our traction battery cells come in 3 formats, DIN Standard being one of them. These cells are all the same width with multiple height, length & weight specifications to enable a perfect fit for a range of applications. 6 EPzS 930 Download PDF Add to quote Additional information Brand Pegasus Range DIN Standard – Wet Vented 2 Volt Cell Volts 2 Cap [C5 Ah] 930 Weight 50.1 kg Length 119 mm Width 198 mm Height 710 mm Terminal Type FM10 Technology WET – tubular plate Guarantee/Warranty BSH Vented British Standard (BS) and DIN Batteries (1500 cycles, 4 years, 3+1) Link to comment Share on other sites More sharing options...
JohnD Posted February 11, 2020 Author Share Posted February 11, 2020 You're way ahead of us, Roger, in self sufficiency for power! You're using lead-acid batteries? Have you considered second hand electric vehicle battery packs? John Link to comment Share on other sites More sharing options...
thebrookster Posted February 11, 2020 Share Posted February 11, 2020 2 hours ago, rogerguzzi said: Hello All What with all this wind and a bit of sun no generator power needed for the last 4 days and new batteries fully charged and I have just turned the immersion heater on to use some of the excess power! This is the size we have now and rated at 930 amp/hrs a C5 1081 amp/hours at C10 1114 amp/hrs at C20 usual car battery standard 1423 amp/hrs at C100 C stands for how much power can be removed at these number of hours (I case anyone does not know) Roger DIN Standard 2 Volt Cells All our traction battery cells come in 3 formats, DIN Standard being one of them. These cells are all the same width with multiple height, length & weight specifications to enable a perfect fit for a range of applications. 6 EPzS 930 Download PDF Add to quote Additional information Brand Pegasus Range DIN Standard – Wet Vented 2 Volt Cell Volts 2 Cap [C5 Ah] 930 Weight 50.1 kg Length 119 mm Width 198 mm Height 710 mm Terminal Type FM10 Technology WET – tubular plate Guarantee/Warranty BSH Vented British Standard (BS) and DIN Batteries (1500 cycles, 4 years, 3+1) Roger, Would you consider creating a thread detailing what equipment (turbines etc) you have, how it is all connected, battery storage etc etc? I ask because you have made mention of your renewable energy in various threads, it would be nice to see what it is you have actually done, and possibly a source of inspiration to the rest of us considering this kind of thing. You seem to have succeeded, maybe you have some lessons for us? Not just limited to yourself of course, if anyone else also has similar systems/setups they could join in? I suspect this may become something more and more of us will have to consider in coming years (see 2035 thread for example), and I think it fits the concept of a sideways technology Cheers, Phil Link to comment Share on other sites More sharing options...
rogerguzzi Posted February 11, 2020 Share Posted February 11, 2020 Hello Phil Ok but will be is dribs and drabs as the old memory is not what it was! Plus I have bought and blown up plenty of stuff over the years! Roger ps I will call it Living Off Grid Link to comment Share on other sites More sharing options...
PeterC Posted February 11, 2020 Share Posted February 11, 2020 38 minutes ago, thebrookster said: Roger, Would you consider creating a thread detailing what equipment (turbines etc) you have, how it is all connected, battery storage etc etc? I ask because you have made mention of your renewable energy in various threads, it would be nice to see what it is you have actually done, and possibly a source of inspiration to the rest of us considering this kind of thing. You seem to have succeeded, maybe you have some lessons for us? Not just limited to yourself of course, if anyone else also has similar systems/setups they could join in? I suspect this may become something more and more of us will have to consider in coming years (see 2035 thread for example), and I think it fits the concept of a sideways technology Cheers, Phil +1 Peter Link to comment Share on other sites More sharing options...
thebrookster Posted February 11, 2020 Share Posted February 11, 2020 2 hours ago, rogerguzzi said: Hello Phil Ok but will be is dribs and drabs as the old memory is not what it was! Plus I have bought and blown up plenty of stuff over the years! Roger ps I will call it Living Off Grid Top Man!! Phil Link to comment Share on other sites More sharing options...
mattius Posted February 12, 2020 Share Posted February 12, 2020 The one time i would have been happy to be snowed in and we barely got a dusting! Proved an interesting few drives home from work though, my BMW is useless in anything other than bone dry, but turns out my car share's Tesla on standard tyres is nearly just as bad despite being 4wd (too much torque). Is it just me or does the Met office seem very keen these days to issue weather warnings, we have been in an amber warning for the last 3 days, its just been normal Scottish winter weather, or can they not predict exactly where it will be? Link to comment Share on other sites More sharing options...
thebrookster Posted February 12, 2020 Share Posted February 12, 2020 Aye, full agreement with you there Matt, weather warnings these days seem to be given at the drop of a hat. Out of interest, what tyres do you have on the BMW? I was amazed in January when I went to Niederau (Austria) for skiing to see nearly 2 dozen BMW's happily negotiating all the ice and snow with no issues, which I can only put down to proper winter tyres. This is the improved weather for today: Fingers crossed the wind is good tomorrow, as I plan to pop up to Glencoe for some skiing all going well! Cheers, Phil Link to comment Share on other sites More sharing options...
mattius Posted February 12, 2020 Share Posted February 12, 2020 Normal tyres, don't see the point of changing for the one week a year it's bad. Although I did have snow tyres on my mx5 when I commuted from Aberdeen and the difference was incredible even in the wet. Cairngorms seem to have got a good dump last night, we were there last month and there was nothing. Link to comment Share on other sites More sharing options...
Nick Jones Posted February 12, 2020 Share Posted February 12, 2020 2 hours ago, mattius said: Normal tyres, don't see the point of changing for the one week a year it's bad Given the Scottish climate (and most of the UK FWIW), I think you may have it the wrong way up. Probably do better to run winter tyres for most of the year and swap to normal tyres for a few weeks in the summer Link to comment Share on other sites More sharing options...
PeterC Posted February 12, 2020 Share Posted February 12, 2020 2 hours ago, Nick Jones said: Given the Scottish climate (and most of the UK FWIW), I think you may have it the wrong way up. Probably do better to run winter tyres for most of the year and swap to normal tyres for a few weeks in the summer The 4x4 runs on winter tyres year round, on the basis that summer storms can flood welsh roads deeper and faster than in winter. When a passenger yells out "stop stop I cant see" as the nearside tyres plough into a puddle, it is reassuring to be able to steer straight. Link to comment Share on other sites More sharing options...
thebrookster Posted February 12, 2020 Share Posted February 12, 2020 Yeah, the 2000 was permanently on winters when she was on the road. The two Skoda's in the household both alternate between summer and winter tyres, mostly down to temperature (when we drop consistently below 10 Deg C I go to winter, above I go to summer). Makes the world of difference for all driving, the increase in grip is massive, particularly on the Octavia (herself's Fabia is another matter, it has no bloody grip anywhere!) The only car that doesn't get changed is the Ranger, but I have All-Terrains with M+S rating fitted to that, and a set of chains for really had stuff. If that gets stuck then things have gotten serious lol. But yeah, I strongly recommend winter tyres. Official guidelines say anything below 7 deg C, and we are pretty much the only country in the EU who does not have this enshrined in law! Cheers, Phil Link to comment Share on other sites More sharing options...
mattius Posted February 12, 2020 Share Posted February 12, 2020 (edited) The Scottish climate is usually exaggerated for Edinburgh, its got really bad once in the last 10 years and i drive down to the borders every day. Been driving RWD BMWs all that time and got stuck twice, both times because i was stupid (driving into a car park with 2ft of snow was never going to end well). Mainly im tight and low profile 18" run flat winter tyres are ridiculously expensive, i grin and bear it. Drive to the conditions of the road. That being said with the way the weather is changing over the last decade, i will be buying a 4wd next time. In the beast from the east 2 years ago we were struggling to get back home and i came across this nutter! Spitfire 1500, in the snow Edited February 12, 2020 by mattius Link to comment Share on other sites More sharing options...
John I Posted February 15, 2020 Share Posted February 15, 2020 A new weekend and Dennis (the Menace) comes to visit. Hold on to your hats, get your waders out and stay safe everyone. Link to comment Share on other sites More sharing options...
Nick Jones Posted February 15, 2020 Share Posted February 15, 2020 Certainly quite wild in Somerset today, and somewhat damp but the worst rain we’ve had so far was actually Wednesday night Thursday morning. Never seen our stream flood before...... admittedly this was partly due to a maintenance failing by our downstream neighbour and his sheep field was a lake (I spent a couple of hours in the afternoon dealing with that) And this substantial hail drift in a village Two miles away - this taken a good three hours after the squall that dropped it. Link to comment Share on other sites More sharing options...
GT6MK3 Posted February 15, 2020 Share Posted February 15, 2020 I got a giggle from this one here in Aus last week (Disclaimer, this is as close to my place as London is to Berlin). C. Link to comment Share on other sites More sharing options...
Nick Jones Posted February 15, 2020 Share Posted February 15, 2020 Yeah.... bush fire risk looks fairly low just now. But where did I put my boat.....? Proper windy here now. Dennis has just had most of the felt off the shed roof...... That's the (formerly) better shed that wan't previously leaking! Neighbour over the lane has a couple of gumtrees that are suffering mightily. Hope they are feeling strong as they both overhang our power lines...... Link to comment Share on other sites More sharing options...
RedRooster Posted February 15, 2020 Share Posted February 15, 2020 1 hour ago, Nick Jones said: Dennis has just had most of the felt off the shed roof...... Mine too. Link to comment Share on other sites More sharing options...
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