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openspaceman

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Everything posted by openspaceman

  1. Meccalte S20FS-160 10 KVA Single Phase Alternator | Honda Engines and Generators | Gear GB WWW.GEARGB.CO.UK Meccalte S20FS-160 10 KVA Single Phase Alternator |Honda Engines and Generators | Gear GB
  2. Looks like a replacement is available for £450 inc VAT
  3. Growing Hawthorn From Seed (Video) WWW.GARDENERSWORLD.COM Find out how to grow your own hawthorn from seeds collected from berries.
  4. from what @Squaredy says I suspect it was not the main engine Many generators were just standby and didn't run a lot so the Mawdsley may be a sensible buy, it depends on how much you need to run the saw. Also consider there will be a lot of heat given off which could be used to dry logs. One thing I do know from having installed a Petter genset for a remote school classroom was the conversion efficiency goes down a lot at low power levels. My guess is it needs to spend most of its time at 70% load.
  5. How many wires run to the transformer? I think you mean 11kV. The nearest mill to me had a 54" Stenner and a 48" resaw and that ran off the engine from a Uboat.
  6. This makes good sense although you will need a good run of 3/4" pressure hose though the return hosewill be cheaper
  7. I have never measured the temperature but the handles get warm within a bout 30 seconds. I'd guess about 40C They're a godsend when you have wet gloves and you are cutting for the chipper but I too don't keep them on very long when working hard.
  8. Yes 5kW is the maximum a 5kVA genset will output but this is into a purely resistive load, when you run a motor aside from the inrush current ( well it's not really inrush but a higher current until the motor is spinning fast enough that the back EMF (Electro Motive Force) reduces the current) the load is inductive because of the motor coils, this means the current lags the voltage so that while instantaneously the current and voltage are out of phase the voltage must stay at ~230V but the current must not exceed the current rating of 22 amps. This means if the power factor of the motor is 0.8 you are only able to supply it with 4kW. These capacitor excited alternators are a weird black art to design but they are simple. This one seems to run at 3000RPM so it probably has a coil and diode in the rotor wound to give a north and south pole when it is energised. This then creates a magnetic flux which passes the main output coil. In this instance the output is only 100V open circuit so for some reason the magnetic flux hasn't saturated and I suspect the diode in the rotor or more likely there is a temperature limiting device, like a thermistor has failed in the rotor circuit. The rotor is energised by the exciter coil and capacitor, @the village idiot says he changed the capacitor and unless the rotor residual magnetism is sufficient to excite the output to 100V by itself this circuit is okay.
  9. The chart shows the current chance of dying is a bit over 1% at 70 but statistics from China show that the chances of dying at 70 if you get covid is 8% however the chances increase 1.5 times if you are male. UK predictions based on those dying in hospital are much better but hospitals are becoming inundated.
  10. Me too plus I'm not so sanguine about the BBC chart showing my personal chances of dying this year have increased from 1% to 10%
  11. It may be cheaper to get a new one but the engine will still be good. The difficulty in reusing these things is the alternator is built onto the motor and only has a bearing at the outer end making alternatives difficult to fit.
  12. When he fixes it let us know what went wrong. It sounds like one of the field coils isn't getting excited.
  13. Difference is one is lawful the other is not, not that it will make any difference.
  14. It's a reasonable compromise, after all the intent is to slow the spread so that it becomes manageable. Currently there are 18 thousand confirmed cases and estimated about 200 thousand people with it, many being unaware. So the chances of being downnwind of one in a population of 60 million is small. Also no one seems to know what load of virus gives the infection or how many viruses are produced by an ill person. My guess is they hope there to be no more than half a million infected at one time but currently they say only 155 people are recovered from the disease, that will take a very long time to work through the population.
  15. I think @tree-fancier123 has covered it. As I read it most infected people out in the open air will cough out relatively large droplets, the chance of breathing one in will be small beyond 2 metres. In other, indoor, situations where droplets may be smaller ( I don't know why but they mention hospital procedures) the virus stays in the air and half of them disappear after 3 hours, it would take a further 3 hours to half the remainder and so on. Now this may have limited consequence to most of us while only a small proportion of the public are infected and in the environment, where droplets and contact with surfaces will remain the main means of infection but with doctors and nurses up close and personal it looks like it becomes significant. IMO they should only be examining people with a full hood, just like those Porton Down technicians did in Salisbury and not worry what the patient thinks.
  16. You misquoted me, I reported a half life in air. A quote from this lady: Dr. Angela Rasmussen (interview recorded March 15, 2020) "Yeah, so a great pre-print just came out. I like to pitch my collaborators at Rocky Mountain Labs, this is Neeltje van Doremalen who is with Vincent Munster at NIAI Rocky Mountain Labs have just released a preprint with some of their colleagues, I believe at Princeton, showing that SARS-coronavirus-2 and SARS classic have some different properties as well as some similar properties for remaining infectious on various surfaces. So they looked at experimentally generated aerosols, which for SARS-coronaviruses is only an issue for the most part in hospital settings where there are aerosol generating procedures, but they showed that for both of these, the aerosol half-life is only about three hours. So that's good news in that you know, if somebody that you love or care about is working in a hospital or an ICU or is getting treated there, these aerosols are not going to persist for days at a time in the environment. They also looked at survival of the virus on copper, stainless steel, plastic and cardboard, and the virus lasts the longest on stainless steel and plastic. So it lasts 48 to 72 hours, and it can potentially be there for longer than that, but what's important to note is that there was a three-log reduction, so a thousand times less virus that was infectious after 72 hours. So, even though you can detect infectious virus on surfaces, plastic or stainless steel surfaces after three days, it's a greatly reduced amount of virus. Compared to SARS classic, SARS-coronavirus-2 lasted longer on cardboard, however it didn't last longer than 24 hours. So before everybody gets worried about getting packages in the mail or opening letters or calling, ordering stuff from Amazon it, it also was essentially undetectable after 24 hours. So cardboard is probably not a surface that's going to retain the virus for, for days and days at a time. What we don't know is the effect that temperature and humidity and other environmental conditions would have on this "
  17. Which I worry is how so many medics are succumbing to it, true a droplet can contain many viruses and falls to the floor quickly but the virology suggests a virus has a half life in air of 3 hours. What is unknown is what viral load entering the lungs will overcome normal defences.
  18. I worked briefly alongside an old lag who was mustard with furniture restoration, a very quiet bloke but he did tell me how his boss would buy a select piece and then he would disassemble it and make new parts, when he reassembled them there were two antiques for sale. He did the time, his boss didn't.
  19. No it's 3ph and draws 12 amps when switched as delta and 7 when switched as star. I think that means you start it star and then once it's running switch to delta although both those voltages time Amps give the same ~2.7kW it makes 2.7 kW with a power factor of .8 so you need to supply 1.25 as many amps at the voltage to get that power. A 3ph Tesla powerwall perhaps might run it.
  20. I've a pond which was excavated in chalk on the woodland I volunteer on, it was lined with clay but plainly leaks as it empties in the summer. how deep does the clay have to be to seal a pond?
  21. Does no one else think this 2m distancing mantra gives a false sense of security? The virus has a half life of 3 hours in air and this 2m advice is based on the rate at which a droplet containing the virus will settle out of the air. I think statistically it may be a decent predictor but, to my mind, because of the rate of infection and morbidity in less than elderly medical staff severe exposure is much worse. ATM no one knows how many viruses infected people shed nor how many virus actually survive the body's defences and mucus membrane to enter a cell and replicate RNA
  22. There was 3 years between my using a 261 and a 550 mk2 but I was impressed by the 550 moreso than the 261 and I felt the shape was better.
  23. My brother's widow gave it away before I could get my hands on it. I got the two bikes though ?
  24. I can't see much plastic being released from a plastic net twixt producer and consumer's black waste bin, washing polyester shirts or strimming grass however...

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