tag:blogger.com,1999:blog-3993498847203183398.post4943199824732141094..comments2024-03-28T09:19:27.451+00:00Comments on RevK<sup>®</sup>'s ramblings: Limits and tolerancesRevKhttp://www.blogger.com/profile/12369263214193333422noreply@blogger.comBlogger34125tag:blogger.com,1999:blog-3993498847203183398.post-46773635783145199362018-03-15T14:35:10.894+00:002018-03-15T14:35:10.894+00:00For the mains in the UK its 230Vac +10%/-6% (might...For the mains in the UK its 230Vac +10%/-6% (might be -10% now) so upper limit is 253Vac. <br /><br />You get paid compensation for every day its above 253V - I know that from personal experience. Was hard to readjust to having to pay them once the substation got sorted :DAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-3993498847203183398.post-14474801405023637732018-03-14T16:25:32.454+00:002018-03-14T16:25:32.454+00:00The Swissgrid explanation - https://www.swissgrid....The Swissgrid explanation - https://www.swissgrid.ch/swissgrid/en/home/experts/topics/frequency.html - is pretty good.<br /><br />Basically, though, the frequency of the grid is set by the relationship between power supplied and power consumed.<br /><br />A big power plant is "just" some source of mechanical energy connected to a spinning generator. If electrical energy consumed is lower than mechanical energy supplied, the spinning generator speeds up, and the frequency climbs; conversely, if consumption is higher than production, the spinning generator slows down, and the frequency falls.<br /><br />The grid operator tries to hold a flat 50 Hz, but can't - they can't adjust either supply or consumption fast enough, so they end up with frequency shifts across the course of the day.<br /><br />Voltage is easier to hold steady - variacs and similar can be designed to adjust the voltage automatically to match the grid's chosen operating point.Simon Farnsworthhttps://www.blogger.com/profile/15190608047563530091noreply@blogger.comtag:blogger.com,1999:blog-3993498847203183398.post-76567153632452424762018-03-13T13:52:22.805+00:002018-03-13T13:52:22.805+00:00In short, yes.
Same is true of most electric cars...In short, yes.<br /><br />Same is true of most electric cars - the AC chargers (and the AC charging specs) are all based around defined current rather than defined power so if the supply voltage is high then the car charges faster.mgboyeshttps://www.blogger.com/profile/11087136219633309258noreply@blogger.comtag:blogger.com,1999:blog-3993498847203183398.post-48439141659473270512018-03-12T21:39:56.683+00:002018-03-12T21:39:56.683+00:00Does the Tesla charge faster at higher voltages?Does the Tesla charge faster at higher voltages?Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-3993498847203183398.post-86732942983305285352018-03-12T21:38:47.620+00:002018-03-12T21:38:47.620+00:00Fascinating... could you tell more about this plea...Fascinating... could you tell more about this please? Do they somehow mix frequencies? Wouldn’t that create a beat pattern? Also does this mean there is a natural tendency for the supply to be above 50Hz for some reason?Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-3993498847203183398.post-55495009600278902432018-03-12T19:52:32.261+00:002018-03-12T19:52:32.261+00:00Is it a risk having manufactured squillions of the...Is it a risk having manufactured squillions of these things, having them sat on a shelf and potentially now finding that they will never receive approval and every single one will have to be scrapped? Is it safer to wait for approval and then commence manufacture?Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-3993498847203183398.post-65100864833840342012018-03-12T16:48:31.232+00:002018-03-12T16:48:31.232+00:00Lived in Japan for many years. 100V on the nose d...Lived in Japan for many years. 100V on the nose day in day out. Even after 3/11 caused significant generation outages (Fukushima etc.). The Japanese don't do tolerances, that requires someone to make a judgement call. All domestic kit is labelled simply 100V.<br /><br />Here in the UK, our mains regularly gets into the high 250's causing the UPS' trim function to kick in. <br />Alannoreply@blogger.comtag:blogger.com,1999:blog-3993498847203183398.post-2636891178614476992018-03-12T09:36:42.335+00:002018-03-12T09:36:42.335+00:00Apologies for bringing everything back to a popula...Apologies for bringing everything back to a popular/pet topic but...<br /><br />Tesla used to quote 85-265V as the input voltage range of their cars' onboard chargers. But they've recently removed that claim (and are now silent on the subject).<br /><br />For them I doubt the change in declaration was a regulatory thing - there's an odd loophole that electric cars aren't subject to CE testing because they're not considered to be 'appliances'. <br /><br />Instead it's the charging points that have to be tested and approved, which is a bit silly since really they're just mains extension leads with safety interlocks.mgboyeshttps://www.blogger.com/profile/11087136219633309258noreply@blogger.comtag:blogger.com,1999:blog-3993498847203183398.post-23240424058576769072018-03-11T21:26:45.680+00:002018-03-11T21:26:45.680+00:00Not just allowed. The UK mains is *required* to be...Not just allowed. The UK mains is *required* to be below 50Hz as much as necessary to bring the average frequency down to exactly 50Hz. :)Nick Alcockhttps://www.blogger.com/profile/06590610308528769844noreply@blogger.comtag:blogger.com,1999:blog-3993498847203183398.post-89570290039574355992018-03-11T14:48:16.520+00:002018-03-11T14:48:16.520+00:00I have no mains feed to my garage. I use a UPS ins...I have no mains feed to my garage. I use a UPS instead to run the lights, I have a pair of the UPS and alternate which is in the house on charge and which in use. The UPS has switchable output voltage, the higest it will do is 196V. I have to be careful what lights I use, I currently have a 32W electronic ballast fluerescent in there.<br /><br />So anyway, there is a use for things other than 110V or 240V. For a start there is 100V and 220V nominal in some places, and then there are UPSs.Owen Smithnoreply@blogger.comtag:blogger.com,1999:blog-3993498847203183398.post-65366716926967055922018-03-11T09:36:51.687+00:002018-03-11T09:36:51.687+00:00Quite. We are working in the DC labelling next.Quite. We are working in the DC labelling next.RevKhttps://www.blogger.com/profile/12369263214193333422noreply@blogger.comtag:blogger.com,1999:blog-3993498847203183398.post-77283971992193432642018-03-11T09:14:12.822+00:002018-03-11T09:14:12.822+00:00Hi Everyone, apologies for the slightly off topic ...Hi Everyone, apologies for the slightly off topic post. However I wanted to say congratulations to RevK on getting the nickname trademarked (I’ve only just noticed the little R in the circle in the blog title; don’t think it was there yesterday and the patent office website is down for maintenance at the moment so I can’t check when it was registered).<br /><br />Also why not look at this photo of an underwater sea cable. Isn’t it interesting, all that protection for those tiny little strands! https://i.redd.it/bbw2h6qf70l01.jpg<br /><br />Have a nice day everyoneAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-3993498847203183398.post-30266254426467773622018-03-11T08:58:12.445+00:002018-03-11T08:58:12.445+00:00This raises an interesting question: I wonder what...This raises an interesting question: I wonder what they do in Germany. I bet over there they state the figures just like an engineer would. Does anybody on here know?Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-3993498847203183398.post-48977853365917037182018-03-11T08:56:40.262+00:002018-03-11T08:56:40.262+00:00Interesting point. I wonder if it’s just voltage, ...Interesting point. I wonder if it’s just voltage, frequency and current figures that are regulated - but not power consumption. It’s a crazy old world, not least because people are only ever going to run AC things at 240v or 110v anyway. I wonder if these crazy regulations also apply to DC devices.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-3993498847203183398.post-82143170266268855732018-03-10T22:15:03.939+00:002018-03-10T22:15:03.939+00:00What's the tolerance on the 15W?What's the tolerance on the 15W?BWhttps://www.blogger.com/profile/07930082365271521270noreply@blogger.comtag:blogger.com,1999:blog-3993498847203183398.post-33455188821353422422018-03-10T17:19:54.378+00:002018-03-10T17:19:54.378+00:00Well, these safety standards are new, we did not h...Well, these safety standards are new, we did not have to do them last time, so maybe that, or maybe just people not quite complying correctly. After all, there is not really a lot of enforcement of this shit.RevKhttps://www.blogger.com/profile/12369263214193333422noreply@blogger.comtag:blogger.com,1999:blog-3993498847203183398.post-70627748403423526142018-03-10T17:17:54.840+00:002018-03-10T17:17:54.840+00:00I see a suprising amount of equipment that does sa...I see a suprising amount of equipment that does say 85-264 so clearly this is a common standard a lot of stuff is built to. But why did the 10% idiocy not apply to this equipment? 47 - 63Hz seems quite common too, which is much clearer than 50 - 60.Owen Smithnoreply@blogger.comtag:blogger.com,1999:blog-3993498847203183398.post-50848320071348534502018-03-10T17:11:57.280+00:002018-03-10T17:11:57.280+00:00Testers are only doing their job. The people that ...Testers are only doing their job. The people that wrote the rules on the other hand are clearly dickheads. What if the tolerance is changed to 5% and my 250V mains exceeds that? How would I know?Owen Smithnoreply@blogger.comtag:blogger.com,1999:blog-3993498847203183398.post-7215228374057115382018-03-10T13:04:46.716+00:002018-03-10T13:04:46.716+00:00Thanks, but how does anyone Dutch ever real any te...Thanks, but how does anyone Dutch ever real any technical drawing if that is the case? Wow.RevKhttps://www.blogger.com/profile/12369263214193333422noreply@blogger.comtag:blogger.com,1999:blog-3993498847203183398.post-39679759681993211842018-03-10T13:03:18.697+00:002018-03-10T13:03:18.697+00:00I can confirm that in Dutch, the symbol ± does, in...I can confirm that in Dutch, the symbol ± does, in fact, mean 'about'. Tonyvhttps://www.blogger.com/profile/17922308113817830218noreply@blogger.comtag:blogger.com,1999:blog-3993498847203183398.post-65666453190210318972018-03-10T12:29:33.093+00:002018-03-10T12:29:33.093+00:00We would, if not for the requirement for a CE mark...We would, if not for the requirement for a CE mark on the product before we sell it, and that the testing and compliance to be able to do that mean we have to state the range of nominal supply voltages, i.e. in our case 100V to 240V.RevKhttps://www.blogger.com/profile/12369263214193333422noreply@blogger.comtag:blogger.com,1999:blog-3993498847203183398.post-72739445572399776792018-03-10T12:10:56.659+00:002018-03-10T12:10:56.659+00:00Just state that the supply voltage should be betwe...Just state that the supply voltage should be between 85-264V including tolerances.0rynhttps://www.blogger.com/profile/15253596186708672382noreply@blogger.comtag:blogger.com,1999:blog-3993498847203183398.post-41404529949382588022018-03-10T11:14:46.984+00:002018-03-10T11:14:46.984+00:00Or original intent was simply to report the actual...Or original intent was simply to report the actual limits based on the specifications of the power supply module, i.e. 85-264RevKhttps://www.blogger.com/profile/12369263214193333422noreply@blogger.comtag:blogger.com,1999:blog-3993498847203183398.post-1247051987745173372018-03-10T11:05:07.777+00:002018-03-10T11:05:07.777+00:00Can't see why anyone should want to refer to 2...Can't see why anyone should want to refer to 264V these days (i.e. 240V + 10%). The EU ruled that the European systems should be be standardised at a nominal 230V but in reality nothing much happened, the existing 220V and 240 systems just carried on regardless. To reflect this reality, the UK limits were bodged to become +6% and -10% so that the upper limits (253V and 254.4V) are now virtually the same for both systems.<br /><br />So if you really wanted to set absolute limits for a product that would work anywhere, surely they should be 90V (Japan's 100V less 10%) and 254.4V (UK's 230V plus 6%)?Gerry1http://idonthaveaurl.org.uknoreply@blogger.comtag:blogger.com,1999:blog-3993498847203183398.post-13026928897568666302018-03-10T09:04:40.100+00:002018-03-10T09:04:40.100+00:00Well, yes, I sort of see what you are saying, but ...Well, yes, I sort of see what you are saying, but two issues:<br /><br />1. That only works if the tolerance (10%) is the same for both things. It is in this case, but if you were in a country with 100V supply and 15% tolerance, the 100V-240V device may not work. To actually check you have to know the tolerances, and if different you then have to work out the actual range to tell!<br /><br />2. If the device said 90V to 264V, you would also assume your 100V supply would be fine, and similarly equipment 45V to 110V would be fine. So forcing the labels to be basically lies does not actually help matters does it?RevKhttps://www.blogger.com/profile/12369263214193333422noreply@blogger.com